CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (USD $) In Thousands, unless otherwise specified	12 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 14,907us-gaap_NetIncomeLoss	$ 5,641us-gaap_NetIncomeLoss	$ 4,076us-gaap_NetIncomeLoss
Other comprehensive income (loss):
Change in funded status of the defined benefit post retirement plan, net of taxes	34	187	(110)
Comprehensive income	$ 14,941us-gaap_ComprehensiveIncomeNetOfTax	$ 5,828us-gaap_ComprehensiveIncomeNetOfTax	$ 3,966us-gaap_ComprehensiveIncomeNetOfTax

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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