Debt - Revolving Line of Credit (Details) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
Debt Instrument [Line Items]
Revolving line of credit	$ 0	$ 33,881
Proceeds from revolving line of credit	0	12,000	$ 10,000
Repayments of line of credit	33,881	12,000	$ 9,600
US Facility
Debt Instrument [Line Items]
Revolving line of credit	0	31,881
Proceeds from revolving line of credit	0
Repayments of line of credit	$ 31,881
Domestic Line of Credit | Base Rate
Debt Instrument [Line Items]
Stated interest rate (as a percent)	5.00%
Spread on variable rate basis (as a percent)	1.50%
Letter of Credit Two | Singapore Facility
Debt Instrument [Line Items]
Revolving line of credit		$ 2,000
90 Day Borrowing Term | Singapore Facility
Debt Instrument [Line Items]
Proceeds from revolving line of credit	$ 0
Repayments of line of credit	2,000
30 Day Borrowing Term | Singapore Facility
Debt Instrument [Line Items]
Revolving line of credit	$ 0
30 Day Borrowing Term | Singapore Facility | LIBOR
Debt Instrument [Line Items]
Stated interest rate (as a percent)	3.375%
Spread on variable rate basis (as a percent)	2.50%