Estimated Fair Values of the Assets Acquired and Liabilities Assumed (Detail) - USD ($) $ in Thousands	Mar. 31, 2016	Mar. 31, 2015	Jul. 31, 2014	Jul. 01, 2014	Mar. 31, 2014
Acquired assets:
Goodwill	$ 33,003	$ 31,534			$ 37,990
Long-term deferred tax assets, net	$ 58,534	$ 80,306
ECP Entwicklungsgesellschaft mbH
Acquired assets:
Cash and cash equivalents				$ 53
Accounts receivable				25
Property and equipment				619
In-process research and development			$ 18,500	18,500
Goodwill				1,964
Long-term deferred tax assets, net				1,874
Other assets acquired				141
Total assets acquired				23,176
Liabilities assumed:
Accounts payable				295
Accrued liabilities				131
Long-term deferred tax liabilities				1,000
Total liabilities assumed				1,426
Net assets acquired				$ 21,750