Fair Value Measurements - Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - Fair Value, Measurements, Recurring [Member] - USD ($)	Sep. 30, 2017	Mar. 31, 2017
Assets:
Cash equivalents	$ 1,006,000	$ 2,003,000
Foreign currency forward contracts	80,000
Total assets measured at fair value on a recurring basis	1,086,000	2,003,000
Liabilities:
Foreign currency forward contracts		96,000
Total liabilities measured at fair value on a recurring basis	0	96,000
Level 1 [Member]
Assets:
Cash equivalents	1,006,000	2,003,000
Total assets measured at fair value on a recurring basis	1,006,000	2,003,000
Level 2 [Member]
Assets:
Foreign currency forward contracts	80,000
Total assets measured at fair value on a recurring basis	$ 80,000
Liabilities:
Foreign currency forward contracts		96,000
Total liabilities measured at fair value on a recurring basis		$ 96,000