Line of Credit - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	6 Months Ended
	Sep. 30, 2013 Loans
Debt Disclosure [Abstract]
Credit facility with borrowing capacity	$ 10
Debt instrument, basis spread on variable rate	1.50%
Fluctuating rate determined by financial institution	Fluctuating rate determined by the financial institution to be 1.50% above the daily one-month LIBOR rate
Debt to tangible net worth not greater than	Debt to tangible net worth not greater than 1.25:1
Current assets to liabilities ratio	1.25
Debt to tangible net worth	1.25
Number of Outstanding revolving loans at any time during fiscal period	0
Letters of credit in aggregate amount	$ 8.0
Renewed credit agreement expiration period	September 2014