Income Taxes (Tables)

12 Months Ended

Dec. 31, 2018

Income Tax Disclosure [Abstract]

Summary of Loss from Operations Before Income Taxes Categorized Geographically

Loss from operations before income taxes is categorized geographically as follows:

	Year Ended December 31,
(in thousands)	2018			2017			2016
United States	$	(152,045	)	$	(40,775	)	$	(64,220	)
Foreign		(2,547	)		718			(7,426	)
Total loss from operations before income taxes	$	(154,592	)	$	(40,057	)	$	(71,646	)

Schedule of Provision for (Benefit from) Income Taxes

The provision for (benefit from) income taxes consisted of the following:

	Year Ended December 31,
(in thousands)	2018			2017			2016
Current income tax expense:
Federal	$	(70	)	$	(12	)	$	(6	)
State		48			23			45
Foreign		677			790			327
Total current income tax expense		655			801			366
Deferred income tax expense:
Federal		(483	)		(16,141	)		4,109
State		562			(248	)		311
Foreign		(586	)		(459	)		(82	)
Total deferred income tax expense		(507	)		(16,848	)		4,338
Total provision for (benefit from) income taxes	$	148		$	(16,047	)	$	4,704

Summary of Reconciliation of Company's Effective Tax Rate to Federal Statutory Rate

A reconciliation of the Company’s effective tax rate to the federal statutory rate is as follows:

	Year Ended December 31,
(in thousands)	2018			2017			2016
Tax at federal statutory rate	$	(32,464	)	$	(14,020	)	$	(25,076	)
State income tax, net of federal tax benefit		(6,764	)		(3,898	)		(2,255	)
Foreign tax rate differential		626			(493	)		2,805
Stock-based compensation		2,378			2,645			1,981
Transition tax		—			2,261			—
Revaluation of deferred tax assets and liabilities		—			(10,259	)		—
Research and development credits		(5,247	)		(4,028	)		(992	)
Intangible asset write-off		—			—			2,434
Other		(106	)		659			2,092
Change in valuation allowance		41,725			11,086			23,715
Total provision for (benefit from) income taxes	$	148		$	(16,047	)	$	4,704

Summary of Tax Effects of Temporary Differences Portions of Company's Deferred Tax Assets and Liabilities

As of December 31, 2018 and 2017, the tax effects of temporary differences that give rise to significant portions of the Company’s deferred tax assets and liabilities are as follows:

(in thousands)	December 31, 2018			December 31, 2017
Deferred tax assets:
Net operating losses	$	41,419		$	27,046
Tax credits		23,359			12,110
Stock-based compensation		25,208			11,372
Accrued compensation and related expenses		4,061			1,843
Financing obligation- leased facility		29,842			24,122
Other		463			1,462
Total deferred tax assets:		124,352			77,955
Valuation allowance		(81,127	)		(34,664	)
Total deferred tax assets, net of valuation allowance:		43,225			43,291
Deferred tax liabilities:
Depreciation and amortization		(26,844	)		(30,708	)
Goodwill		(19,307	)		(16,017	)
Total deferred tax liabilities:		(46,151	)		(46,725	)
Total net deferred tax liabilities:	$	(2,926	)	$	(3,434	)

Summary of Changes in Balances of Gross Unrecognized Tax Benefits

Changes in balances during 2018 and 2017 and ending balances as of December 31, 2018 and 2017 in gross unrecognized tax benefits were as follows:

(in thousands)	December 31, 2018			December 31, 2017
Beginning balances	$	1,486		$	4,273
Increases related to tax positions taken during a prior year		584			2
Increases related to tax positions taken during the current year		1,351			288
Decreases related to tax positions taken during a prior year		(70	)		(2,785	)
Decreases related to tax settlements with taxing authorities		—			(292	)
Ending balances	$	3,351		$	1,486