Fair Value Measurements - Changes in Fair Value of Level 3 Assets and Liabilities on a Recurring Basis (Details) (Corporate-owned life insurance [Member], USD $) In Thousands, unless otherwise specified	12 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Corporate-owned life insurance [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance at beginning of period	$ 3,458	$ 3,323
Realized gains	0	46
Unrealized gain relating to instruments held at reporting date	107	371
Purchases, sales, issuances and settlements, net	108	(282)
Balance at end of period	$ 3,673	$ 3,458