Annual report pursuant to Section 13 and 15(d)

Income Taxes - Components of Income Before Income Taxes (Detail)

v2.4.1.9
Income Taxes - Components of Income Before Income Taxes (Detail) (USD $)
In Thousands, unless otherwise specified
 12 Months Ended
Mar. 31, 2015
Mar. 31, 2014
Mar. 31, 2013
Income Taxes [Line Items]      
Income before income taxes, total $ 21,752us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest $ 14,710us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest $ 15,577us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest
U.S. [Member]      
Income Taxes [Line Items]      
Income before income taxes, total 20,799us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest
/ us-gaap_StatementGeographicalAxis
= country_US 		14,127us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest
/ us-gaap_StatementGeographicalAxis
= country_US 		14,597us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest
/ us-gaap_StatementGeographicalAxis
= country_US
China [Member]      
Income Taxes [Line Items]      
Income before income taxes, total $ 953us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest
/ us-gaap_StatementGeographicalAxis
= country_CN 		$ 583us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest
/ us-gaap_StatementGeographicalAxis
= country_CN 		$ 980us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest
/ us-gaap_StatementGeographicalAxis
= country_CN