Components of Net Deferred Taxes (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Mar. 31, 2017
Deferred tax assets
Non-operating loss and tax credit carryforwards	$ 48,724	$ 8,814
Stock-based compensation	13,271	16,560
Nondeductible reserves and accruals	8,290	10,303
Foreign non-operating loss carryforwards	9,598	13,634
Deferred revenue	3,770	4,308
Depreciation and amortization	826	2,135
Other, net	822	1,308
Deferred Tax Assets, Gross, Total	85,301	57,062
Deferred tax liabilities
Goodwill	(6,787)	(9,444)
In-process research and development	(5,045)	(4,374)
Depreciation	(1,011)
Domestic deferred tax liability on foreign non-operating loss carryforwards	(963)	(6,836)
Deferred Tax Liabilities, Net	(13,806)	(20,654)
Net deferred tax assets	71,495	36,408
Valuation allowance	(1,652)	(2,468)
Net deferred tax assets	69,843	33,940
Long-term deferred tax assets, net	70,746	34,723
Long-term deferred tax liabilities	(903)	(783)
Net deferred tax assets	$ 69,843	$ 33,940