FAIR VALUE MEASUREMENTS - Input Hierarchy of Items Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Mar. 31, 2018	Sep. 30, 2017
Total Assets / Liabilities at Fair Value
Assets
Derivative financial instruments	$ 0	$ 0	$ 64
Securitized beneficial interests	17,512	48,715	23,668
Total assets	17,512	48,715	23,732
Liabilities
Long-term debt	897,970	912,159	852,082
Guarantees	1,861	5,864	2,770
Total liabilities	899,831	918,023	854,852
Level 2
Assets
Derivative financial instruments	0	0	64
Securitized beneficial interests	0	0	0
Total assets	0	0	64
Liabilities
Long-term debt	897,264	911,264	852,082
Guarantees	0	0	0
Total liabilities	897,264	911,264	852,082
Level 3
Assets
Derivative financial instruments	0	0	0
Securitized beneficial interests	17,512	48,715	23,668
Total assets	17,512	48,715	23,668
Liabilities
Long-term debt	706	895	0
Guarantees	1,861	5,864	2,770
Total liabilities	$ 2,567	$ 6,759	$ 2,770