Income Taxes (Tables)

12 Months Ended

Dec. 31, 2018

Income Tax Disclosure [Abstract]

Components of Income Before Income Taxes

For financial reporting purposes, income before income taxes includes the following components (in thousands):

	Years Ended December 31,
	2018		2017			2016
United States	$	16,312	$	(42,863	)	$	134,740
Foreign		75,487		86,435			50,841
Total	$	91,799	$	43,572		$	185,581

Income Tax Expense (Benefit)

The expense (benefit) for income taxes consists of the following (in thousands):

	Years Ended December 31,
	2018			2017			2016
Federal
Current	$	6,545		$	2,586		$	14,108
Deferred		(6,587	)		19,212			19,034
Total		(42	)		21,798			33,142
State
Current		4,441			(1,857	)		12,565
Deferred		(2,649	)		(1,324	)		(2,502	)
Total		1,792			(3,181	)		10,063
Foreign
Current		17,626			16,048			11,671
Deferred		3,502			3,772			1,170
Total		21,128			19,820			12,841
Total	$	22,878		$	38,437		$	56,046

Summary of Differences Between Income Tax Expense Computed at Statutory Federal Income Tax Rate and Per Consolidated Statements of Operations

Differences between the income tax expense computed at the statutory federal income tax rate and per the consolidated statements of operations are summarized as follows (in thousands):

	Years Ended December 31,
	2018			2017			2016
Tax expense at federal rate of 21% (35% pre-2018)	$	19,278		$	15,250		$	64,953
State income taxes, net of federal benefit		5,246			(2,238	)		7,060
Change in valuation allowance		12,657			(1,884	)		(8,524	)
Foreign tax rate differential		(4,796	)		(15,622	)		(11,830	)
Unrecognized tax benefit increase		1,262			3,007			1,045
Tax effect of foreign operations		8,546			5,532			5,988
Tax benefit of research & development		(2,557	)		(1,904	)		(1,088	)
Transition tax		(8,112	)		20,867			—
Revaluation of deferred tax balances		(4,937	)		14,953			—
Performance-based compensation		(4,541	)		2,081			—
Domestic production activities		—			(3,793	)		(700	)
Other		832			2,188			(858	)
Income tax provision	$	22,878		$	38,437		$	56,046

Summary of Deferred Tax Assets and Liabilities

The deferred tax assets and liabilities result from differences in the timing of the recognition of certain income and expense items for tax and financial accounting purposes. The sources of these differences at each balance sheet date are as follows (in thousands):

	December 31,
	2018			2017
Deferred income tax assets:
Net operating loss carryforwards	$	25,745		$	38,419
Tax credits		43,838			37,305
Compensation		15,934			18,124
Deferred revenue		27,587			22,248
Research and development expense deferral		12,631			—
Other		5,393			9,055
Gross deferred income tax assets		131,128			125,151
Less: valuation allowance		(20,415	)		(7,808	)
Net deferred income tax assets	$	110,713		$	117,343
Deferred income tax liabilities:
Depreciation and amortization	$	(60,872	)	$	(67,504	)
Deferred revenue		(54,508	)		—
Total deferred income tax liabilities		(115,380	)		(67,504	)
Net deferred income taxes	$	(4,667	)	$	49,839
Deferred income taxes / liabilities included in the balance sheet are:
Deferred income tax asset – noncurrent	$	27,048		$	66,749
Deferred income tax liability – noncurrent		(31,715	)		(16,910	)
Net deferred income taxes	$	(4,667	)	$	49,839

Reconciliation of Beginning and Ending Amount of Unrecognized Tax Benefits

A reconciliation of the beginning and ending amount of unrecognized tax benefits for the years ended December 31 is as follows (in thousands):

	2018			2017			2016
Balance of unrecognized tax benefits at beginning of year	$	27,237		$	24,278		$	21,079
Increases for tax positions of prior years		315			2,478			58
Decreases for tax positions of prior years		(61	)		(114	)		(361	)
Increases for tax positions established for the current period		1,185			1,677			5,185
Decreases for settlements with taxing authorities		—			(154	)		(167	)
Reductions resulting from lapse of applicable statute of limitation		(115	)		(1,155	)		(1,310	)
Adjustment resulting from foreign currency translation		(155	)		227			(206	)
Balance of unrecognized tax benefits at end of year	$	28,406		$	27,237		$	24,278