Business Combination - Summary of Estimated Fair Values of Net Assets Acquired (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Mar. 31, 2015	Jan. 09, 2015
Business Acquisition [Line Items]
Goodwill	$ 9,600	$ 12,500
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Business Acquisition [Line Items]
Inventory			$ 52,676
Purchased intangibles	242,200		242,200
In-process research and development assets	$ 20,900		20,900
Other assets			4,624
Goodwill			9,600
Total assets acquired			330,000
Other liabilities assumed			(5,000)
Total net assets acquired			$ 325,000