Fair Value Measurements Reconciliation of Change in Recurring Level 3 Balances (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Securitized Beneficial Interests [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Ending Balance	$ 21,792		$ 21,792
Fair Value, Measurements, Recurring [Member] | Securitized Beneficial Interests [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning Balance	23,256	$ 24,883	40,712	$ 35,559
Issuances of guarantees/sales of receivables	35,986	43,806	69,767	65,319
Settlements	(36,794)	(32,255)	(87,960)	(63,980)
Losses recognized in earnings	(656)	(1,182)	(727)	(1,646)
Ending Balance	21,792	35,252	21,792	35,252
Fair Value, Measurements, Recurring [Member] | Guarantees [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning Balance	7,723	7,262	8,650	7,344
Issuances of guarantees/sales of receivables	1,812	4,238	6,369	8,519
Settlements	(3,762)	(1,917)	(9,246)	(6,280)
Losses recognized in earnings	(908)	(2,311)	(908)	(2,311)
Ending Balance	$ 4,865	$ 7,272	$ 4,865	$ 7,272