Income taxes.

No definition available.

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- Definition

Expiration date of the operating loss carryforwards.

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No definition available.

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- Definition

Change in deferred tax assets due to release of valuation allowance for deferred income taxes.

+ References

No definition available.

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- Definition

Amount of increase (decrease) in additional paid in capital (APIC) resulting from a tax benefit (deficiency) associated with an share-based compensation plan other than an employee stock ownership plan (ESOP).

+ References

No definition available.

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- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 12
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- Definition

Amount of cash outflow for realized tax benefit related to deductible compensation cost reported on the entity's tax return for equity instruments in excess of the compensation cost for those instruments recognized for financial reporting purposes.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 20
-Section 55
-Paragraph 24
-URI http://asc.fasb.org/extlink&oid=32706628&loc=d3e11374-113907

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- Definition

Current period income tax expense or benefit pertaining to a gain (loss) on an extinguishment of debt.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 50
-Section 40
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=49170532&loc=d3e12317-112629

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- Definition

This element represents the income or loss from continuing operations attributable to the economic entity which may also be defined as revenue less expenses from ongoing operations, after income or loss from equity method investments, but before income taxes, extraordinary items, and noncontrolling interest.

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-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 10
-Article 5

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- Definition

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

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- Definition

Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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- Definition

The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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-Name Accounting Standards Codification
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- Definition

The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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- Definition

Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset.

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Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Taxes [Line Items]
Income (loss) before income tax (expense)		$ 381,318	$ 260,194	$ (42,498)
Excess tax benefits from stock-based compensation		100,243	$ 16,965
Tax impact of extinguishment of Convertible Notes		11,847
Unrecorded excess stock-based compensation tax benefits		$ 3,400
Federal tax provision at statutory rate		35.00%	35.00%	35.00%
Income tax (expense) benefit		$ (136,593)	$ 16,258	$ (115)
Valuation allowance increased (decreased)		800	(104,800)	$ 22,100
Release of valuation allowance for deferred income taxes	$ 33,400		$ 33,403
Gross unrecognized tax that would decrease effective tax rate, if recognized		7,700
California credit carryforwards [Member]
Income Taxes [Line Items]
Research and development credit and orphan drug credit		16,600
Federal [Member]
Income Taxes [Line Items]
Operating loss carryforwards		0
State [Member]
Income Taxes [Line Items]
Operating loss carryforwards		$ 216,300
Operating loss carryforwards, expiration dates		at various dates between the years 2017 and 2033