Income Taxes (Tables)

12 Months Ended

Dec. 31, 2016

Income Tax Disclosure [Abstract]

Schedule of Income before Income Taxes

Income before provision for income taxes was as follows:

	Year Ended December 31,
	2016		2015		2014
	(in thousands)
United States	$	188,078	$	95,644	$	325,081
Foreign	72,429		46,241		24,288
Income before income taxes	$	260,507	$	141,885	$	349,369

Components of Provision for Income Taxes

The components of provision for income taxes for all periods presented were as follows:

	Year Ended December 31,
	2016			2015			2014
	(in thousands)
Current tax provision:
Federal	$	54,315		$	52,557		$	86,623
State	5,790			(1,576		)	9,866
Foreign	60,571			26,918			16,144
Total current	120,676			77,899			112,633
Deferred tax provision:
Federal	(24,383		)	(37,669		)	(10,994		)
State	(14,080		)	(17,635		)	(17,794		)
Foreign	(8,384		)	(3,351		)	(1,275		)
Total deferred	(46,847		)	(58,655		)	(30,063		)
Provision for income taxes	$	73,829		$	19,244		$	82,570

Reconciliation of Provision for Income Taxes

A reconciliation of the provision for income taxes, with the amount computed by applying the statutory Federal income tax rate to income before income taxes is as follows:

	Year Ended December 31,
	2016			2015			2014
	(in thousands)
Expected tax expense at U.S. Federal statutory rate of 35%	$	91,179		$	49,658		$	122,279
State income taxes, net of Federal income tax effect	7,261			4,783			13,274
R&D tax credit	(41,144		)	(29,363		)	(18,655		)
Release of tax reserves on previously unrecognized tax benefits	—			(13,438		)	(38,612		)
Foreign earnings at other than US rates	14,639			5,310			2,959
Other	1,894			2,294			1,325
Provision for income taxes	$	73,829		$	19,244		$	82,570

Deferred Tax Assets and Liabilities

The components of deferred tax assets and liabilities were as follows:

	As of December 31,
	2016			2015
	(in thousands)
Deferred tax assets (liabilities):
Stock-based compensation	$	188,458		$	131,339
Accruals and reserves	29,231			14,367
Depreciation and amortization	(93,760		)	(43,204		)
R&D credits	107,283			74,091
Other	(2,363		)	3,980
Gross deferred tax assets	228,849			180,573
Valuation allowance	(1,601		)	—
Net deferred tax assets	$	227,248		$	180,573

Summary of Changes in Unrecognized Tax Benefits

The aggregate changes in the Company’s total gross amount of unrecognized tax benefits are summarized as follows (in thousands):

Balances as of December 31, 2014	$	34,812
Increases related to tax positions taken during prior periods	1,960
Decreases related to tax positions taken during prior periods	(12,334		)
Increases related to tax positions taken during the current period	7,077
Decreases related to settlements with taxing authorities	(14,398		)
Balances as of December 31, 2015	17,117
Increases related to tax positions taken during prior periods	1,047
Decreases related to tax positions taken during prior periods	(7,105		)
Increases related to tax positions taken during the current period	8,713
Decreases related to expiration of statute of limitations	(33		)
Balances as of December 31, 2016	$	19,739