Income Taxes - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	9 Months Ended
Dec. 31, 2012 Shareholder	Mar. 31, 2012
Income Tax Disclosure [Line Items]
Federal net operating loss carry forwards	$ 2,583
Effective income tax rate expiration in fiscal year	2030
Valuation allowance	265
Current deferred tax assets	6,339	8,861
Non-current deferred tax assets	5,238	4,567
Minimum number of shareholders	1
Type of shareholders	5.00%
Minimum percentage owned by shareholders	5.00%
Increase in the percentage of stock ownership by value	50.00%
Period for change in stock ownership	3 years
Unrecognized tax benefits	$ 0

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Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards expected to be realized or consumed within one year or operating cycle, if longer.

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