Fair Value Measurements - Additional Information (Detail) (USD $)	12 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets measured	$ 1,167,413,000	$ 1,668,260,000
Liquidating distributions payable	42,111,000	16,555,000
Transfers between fair value amount	0	0
Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets measured
Liquidating distributions payable