DETERMINATION OF SUSTAINABLE BUSINESS FACTORS OF ISLAMIC BANKS IN INDONESIA

The objective of the study is to examine the effect of corporate intellectual capital and company size on sustainable business through financial performance as a mediating variable. The data used is secondary data of financial and annual reports for 2010-2018 period. The population of this study is 9 (nine) Islamic Banks, and the samples used are saturated sampling, thus the sample used is all the 9 (nine) Islamic Banks. The data processing method used is Partial Least Square (PLS). The results of the study finds that intellectual capital has a significant effect on financial performance, company size has a significant effect on financial performance, where as intellectual capital has no effect on sustainable business. The study also finds that financial performance has a significant effect on sustainable business. Financial performance has a full mediating influence of intellectual capital on sustainable business, and financial performance has a partial mediating influence of company size on sustainable business.


INTRODUCTION
The development of Islamic banks in Indonesia according to the Financial Services Authority (Indonesian, OJK) 2018 has been documented as for 13 Islamic Banks, 22 Islamic Business Units, 165 Islamic rural banks. The development of Islamic banks in Profitability is one measure for investors to invest, because profitability is a measure used to determine the company's ability to generate profits. Profitability can be used as a means to convey information to investors. Dilling (2009) states that companies with high characteristics of profitability and strong long-term growth will affect on sustainability business. This is in accordance with the research conducted by Maskun (2013), which shows that leverage levels, company size and profitability have a significant and positive impact on disclosure of CSR, which in turn increases the welfare of the community.
Sustainability is a balance between people-planet-profit, known as the triple bottom line (TBL) concept. Sustainability lies in the meeting between three aspects, peoplesocial; planet-environment; and profit-economy (Elkington, 1998). Often companies focus only on increasing profits and using technology as efficiently as possible so that sometimes disregards environmental and social aspects. Along with these conditions, the awareness of the Indonesian people about the importance of the company's environmental and social performance began to grow. This awareness encourages people to want disclosure of information by companies that are not only focused on one aspect of performance, but overall indicators of sustainability performance, economic, social and environmental performance. Companies that ignore social norms will lose goodwill from consumers, workers and regulators (Bary and Bouma, 2009).
Based on the results of the previous discussions, the study aims to firstly examine the effect of intellectual capital on financial performance, secondly to examine the effect of company size on financial performance, thirdly to examine the effect of intellectual capital on business sustainability, fourthly to examine the effect of company size on business sustainability, fifthly to examine effect of financial performance on business sustainability, sixthly to examine intellectual capital on business sustainability mediated financial performance and seventhly to examine company size on business sustainability mediated financial performance.
The study is expected to contribute to the development of financial management sciences, especially the financial management of the Islamic banks, and the application of intellectual capital related to the financial and sustainable business performance of the Islamic banks. In addition, the study is expected to be able to build intellectual capital as part of financial statements. This provides benefits for the Islamic banks to manage their 140 Determination Of Sustainable Business Factors. . . . .

Vol. 27, No. 2 August 2019 © Centre for Indonesian Accounting and Management Research Postgraduate Program, Brawijaya University
intellectual capital and assets for better. This is also in preparation to enter in the global market competition and in competitive advantage for the Islamic banks.

Intellectual Capital
Intellectual capital is an intangible asset owned by an Islamic banks and is used by Islamic banks to generate benefits and improve welfare through value added. In this research the intellectual capital variable is measured by three indicators: human capital

Company size
The company size is the measure of a standard company. The indicator used in this study to measure the level of company size is the total assets of the company (Siswanti, et al, 2017). Company size can be formulated as follows: Size= ln (total assets)

Financial Performance
According to Asmirantho (2013) the notion of financial performance is the determination of certain measures that can measure the success of an organization or company in generating profits. Whereas according to IAI (2007) Financial Performance is the company's ability to manage and control the resources it has. In this study financial ROA = net profit before tax x 100%

Sustainable Business
Sustainable business in this research was measured by 3 aspects namely economic aspects, consits of 6 items, social aspects consits of 10 items and environmental aspects consits of 8 items of questions with reference to the Global Reporting Initiative (GRI) 2013 G4. To get an objective value in measuring sustainable business, an index analysis of scores that is calculated by self-assessment using question items is used, so each Islamic banks can assess the condition of the sustainability of its business.
Furthermore, each item question that is disclosed will be given a value: 3; 2 or 1. Value 3 will be given if the question item is fully disclosed and disclosed in detail in the annual report, value 2 will be given if the item question is only disclosed in the annual report without any detailed explanation and value 1 is given if the question item not disclosed in the annual report. Then the values are summed according to each indicator.

Theoretical Framework and Hypothesis
From the research framework, it can be seen that there is an effect between independent variables on the dependent variable, and financial performance as an intervening variable.

Vol. 27, No. 2 August 2019 © Centre for Indonesian Accounting and Management Research Postgraduate Program, Brawijaya University
Jurgelevicius (2014) states that intangible assets consisting of intellectual capital, human capital and social capital were able to change the economic structure of a country and affected the sustainability of a country's development. Akhtar et al. (2015) stated that intellectual capital has a significant effect on SME's sustainable business. This is different from the results of the research by Juwita and Anggraini (2007) stated that intellectual capital has no effect sustainable business performance.
Furthermore, from the background, there is a research gap from the results of research previously about the influence of company size on sustainable business. The results of Hackston and Milne (1996); Wahyuningsih and Mahdar (2018) state that company size has a significant effect on sustainable business. While the results of Swandari and Sadikin (2016) state that company size has no effect on sustainable business. According to research gap above, the researcher suggested the following hypothesis:

Intellectual Capital On Financial Performance
From the results of previous research, Bontis et al. (2000) stated that structural capital (SC) has a significant effect on business performance. Firer and Williams (2003) state that there is a significant effect, intellectual capital on company performance as measured by profitability, productivity and market valuation. Chen et al. (2005) stated that intellectual capital has a significant effect on financial performance. Ulum et al. (2008) states that intellectual capital has a significant effect on financial performance. Carrington (2012); Fathi et al. (2013); Nawaz et al. (2014); also stated that intellectual capital has a significant effect on financial performance. Based on he above previous research findings it can be explained that intellectual capital has a very major influence for the company because basically, intellectual capital is a resource that has the potential to determine the company's competitive advantage.
This also means that intellectual capital is a factor of resources and knowledge that supports the running of the company. Companies that have high intellectual capital values indicate that the company can combine the existence of resources owned, ranging from human capital (HC), structural capital (SC) to capital employed (CE). With proper intellectual capital management, financial performance will also increase. Based on the

The Company size On Financial Performance
The Company size is a scale which can be classified as the company standard according to various methods, including the total assets. The company size will effect the ability to bear the risks that may arise from various situations faced by the company. Company size also determines the level of investor confidence. The bigger company, the better it is known by the community, which means it is easier to get information that will increase the value of the company. In fact, big company that have total assets with a large enough asset value can attract investors to invest in the company (Prasetyorini, 2013).
Thus companies with a big size have access to sources of funding from various sources, so that getting a loan from a creditor will be easier. In most cases it is because the companies with the big measure have high profit. (2017) states that company size as measured by total assets has a significant effect on financial performance of manufacturing companies listed on the Indonesia Stock Exchange. Likewise, the result of Mwangi (2018) states that company size has a significant effect on financial performance of Commercial Banks in Kenya. Based on the description, the hypothesis can be proposed as follows:

Firmansyah and Suwitho
H2: company size has a significant effect on financial performance

Intellectual Capital On Sustainable Business
As the results of research previously, Dzemyda and Jurgelevicius (2014) stated that intangible assets consist of intellectual capital, human capital and social capital were able to change the economic structure of a country and influence the sustainability of a country's development. Akhtar et al. (2015) stated that intellectual capital has a significant effect on SME's sustainable business.
From the results of research previously it can be explained, companies that have intellectual capital if managed properly can encourage companies to work more effectively and efficiently so as to create a competitive advantage in the business world, encourage improvement in financial performance so that it can form a sustainable business. Based on the description, the following hypotheses can be proposed: H3: Intellectual capital has significant effects on sustainable business 144 Determination Of Sustainable Business Factors. . . . .

Company size On Sustainable Business
Consideration of investment decision making, investors often see the company size and evaluate financial performance. The company size is an estimate variable that is widely used to explain variations in social disclosures in annual reports made by companies. This is related to agency theory that predicts large companies that have higher agency costs will reveal more information in order to reduce the high agency costs (Sembiring, 2006). Larger companies tend to have higher information public demand than smaller companies (Sembiring, 2006). Research of Hackston and Milne (1996) shows that the company size has a significant effect on sustainable business. Based on the description, the following hypotheses can be proposed: H4: Companya size has significant effects on sustainable business

Financial Performance On Sustainable Business
Research Nawaiseh (2015) state that financial performance reflected in return on asset (ROA) has a significant effect on sustainable business. Maskun (2013) stated that leverage, company size and profitability have a significant effect on CSR disclosure, which in turn can improve people's welfare. Sari and Marsono (2013) stated that profitability has a significant effect on disclosure of sustainability report.
From the results of research previously it can be explained that companies that have a good level of financial performance tend to increase investment by opening up lines and branches of business. Thus if a company has good financial performance value, the company will be sustainable. Therefore it can be said that the financial performance of a good company will be able to improve the ability of the company in increasing social responsibility, which in turn will be able to improve people's welfare. Based on the description, the following hypotheses can be proposed:  (2015) that intellectual capital has a significant effect on SME's sustainable business. Akhtar et al. (2015) stated that intellectual capital has a significant effect on SME's sustainable business. This is different from the results of research by Juwita and Anggraini (2007) stated that intellectual capital does not affect sustainable business performance.
Based on the research gap, the researcher wants to examine the effect of intellectual capital on sustainable business through financial performance as a mediating variable.
From this description, the following hypotheses can be proposed: H6: Financial performance mediates the effect of intellectual capital on sustainable business

Financial Performance Mediates Effect of Company size on Sustainable Business
As the results of research previously, Hackston and Milne (1996), Wahyuningsih and Mahdar (2018)   Based on the relationship of variables used in research and problem formulation, this research uses partial least square (PLS) to data analysis techniques. The reason for using partial least square (PLS) because PLS is more predictive model and is a powerful analytical method because it is not based on many assumptions (Ghozali, 2014). For example, data must be normally distributed, samples do not have to be large. Besides being used to confirm the theory, PLS can also be used to explain whether there is a relationship between latent variables. PLS can simultaneously analyze the constructs formed with reflective and formative indicators.
The limitations in this research are not to distinguish the status of the Islamic banks used in this study whether the Islamic banks have status as foreign exchange banks or non-foreign exchange banks.

Test Validity and Reliability
Validity and reliability tests for all variables in this research can be seen from the results of convergent validity, discriminant validity and composite reliability, as shown in table 1 below.

Partial Least Square Analysis
The study uses Smart PLS 3.0 partial least square analysis (PLS). Below is the PLS model as shown in Figure 2 below.

Figure 2
Hypothesis Testing Results

(Data processed 2019)
Based on data processed with PLS, R-Square values can be obtained as shown in the table 3 below.

CONCLUSIONS AND SUGGESTIONS
From the results of the study, it can be concluded that the sustainable business of Islamic banks is influenced by financial factors and non-financial factors. As empirically found, intellectual capital has a significant effect on financial performance.
Company size has a significant effect on financial performance, where as intellectual capital has no effect on sustainable business. The study also finds that financial performance has a significant effect on sustainable business. Financial performance has a full mediating influence of intellectual capital on sustainable business, and financial performance has a partial mediating influence of company size on sustainable business.

LIMITATIONS AND SUGGESTIONS FOR FUTURE RESEARCH
The limitations of this study are not differentiating status of group banks in foreign exchange banks or non-foreign exchange banks. It is recommended for future research to replicate the results of this study by using different research objects, such as other Islamic financial institutions, Islamic insurance companies, and Baitul Maal wa Tamwil (BMT) institutions.