FAIR VALUE, Carrying Amounts and Estimated Fair Value of Financial Instruments Not Carried at Fair Value (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Sep. 30, 2015
Total estimated fair value
Financial assets:
Bank loans, net	$ 14,243,481	$ 12,904,264
Financial liabilities:
Bank deposits	12,733,874	11,923,944
Other borrowings	36,549	38,455
Senior notes payable	1,242,368	1,261,723
Carrying amount
Financial assets:
Bank loans, net	14,208,236	12,907,776
Financial liabilities:
Bank deposits	12,729,457	11,919,881
Other borrowings	35,584	37,716
Senior notes payable	1,149,316	1,149,222
Quoted prices in active markets for identical assets (Level 1)
Financial assets:
Bank loans, net	0	0
Financial liabilities:
Bank deposits	0	0
Other borrowings	0	0
Senior notes payable	367,080	368,760
Significant other observable inputs (Level 2)
Financial assets:
Bank loans, net	93,926	105,199
Financial liabilities:
Bank deposits	12,380,262	11,564,963
Other borrowings	36,549	38,455
Senior notes payable	875,288	892,963
Significant unobservable inputs (level 3)
Financial assets:
Bank loans, net	14,149,555	12,799,065
Financial liabilities:
Bank deposits	353,612	358,981
Other borrowings	0	0
Senior notes payable	$ 0	$ 0