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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Amount of cumulative effect of the change in accounting principle or new accounting pronouncement on retained earnings or other components of equity or net assets in the statement of financial position as of the beginning of the earliest period presented.

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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Organization and Summary of Significant Accounting Policies - Additional Information (Detail) $ in Thousands	3 Months Ended				6 Months Ended		12 Months Ended
	Jun. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Jun. 30, 2017 USD ($)	Jun. 30, 2018 USD ($) Segment	Jun. 30, 2017 USD ($)	Dec. 31, 2017 USD ($)	Jan. 01, 2018 USD ($)
Organization And Summary Of Significant Accounting Policies [Line Items]
Cash and investments in marketable securities	$ 2,106,085		$ 353,220		$ 2,106,085		$ 353,220
Senior secured notes	250,000				$ 250,000
Senior secured notes, maturity date					Oct. 05, 2020
Number of operating business segment \| Segment					1
Revenue recognized from contracts with customers	$ 1,087,717			$ 34,589	$ 1,125,735	$ 59,317
Effective income tax rate	0.50%				0.50%
Benefit of stock-based compensation windfalls					$ 1,900
Statutory income tax rate					21.00%		35.00%
India
Organization And Summary Of Significant Accounting Policies [Line Items]
Effective income tax rate				35.00%		35.00%
Royalty [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Revenue recognized from contracts with customers	$ 8,563			$ 7,434	$ 19,639	$ 14,651
ASC 606 [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Adjustment to retained earnings								$ 12,700
ASC 606 [Member] \| Royalty [Member] \| MOVANTIK and ADYNOVATE [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Revenue recognized from contracts with customers		$ 11,100	$ 9,600
ASC 606 [Member] \| Recognition of Royalties [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Adjustment to retained earnings								10,700
ASC 606 [Member] \| Recognition of Royalties [Member] \| MOVANTIK and ADYNOVATE [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Adjustment to retained earnings								10,700
ASC 606 [Member] \| Reduction of Deferred Revenue [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Adjustment to retained earnings								$ (2,000)