Income Taxes (Tables)

12 Months Ended

Dec. 31, 2019

Components of income before the provision for income taxes and noncontrolling interest

The components of pretax income are summarized as follows (in millions):



	Years Ended December 31,
	2019		2018		2017
Domestic	$	296.2	$	160.6	$	474.2
Foreign	118.2		372.1		337.6
Total pretax income	$	414.4	$	532.7	$	811.8

Schedule of Components of Provision for Income Taxes

The provision (benefit) for income taxes is summarized as follows (in millions):



	Years Ended December 31,
	2019			2018			2017
Current provision (benefit):
Federal	$	6.2		$	(126.1	)	$	594.3
States	14.4			9.0			13.9
Foreign	48.5			38.9			45.4
Total current provision (benefit)	69.1			(78.2		)	653.6
Deferred provision (benefit):
Federal	0.8			36.6			(128.7		)
States	2.8			2.2			(17.7		)
Foreign	(3.3		)	5.2			(1.6		)
Total deferred provision (benefit)	0.3			44.0			(148.0		)
Total provision (benefit) for income taxes	$	69.4		$	(34.2	)	$	505.6

Schedule of Effective Income Tax Rate Reconciliation

The provision (benefit) for income taxes differs from the amount computed by applying the federal statutory rate of 21% for 2019, 21% for 2018, and 35% for 2017, respectively, to pretax income as follows (in millions):



	Years Ended December 31,
	2019			2018			2017
Expected provision at statutory rate	$	87.0		$	111.9		$	284.1
State taxes, net of federal benefit	9.4			7.4			12.0
Foreign income at different tax rates	1.8			(12.8		)	(46.4		)
R&D tax credits	(18.8		)	(22.1		)	(15.1		)
Share-based compensation	3.8			4.7			—
Non-deductible compensation	3.3			1.9			1.6
Temporary differences not currently benefited	12.9			—			—
Recognition of previously unrecognized tax benefits	(25.4		)	—			—
Lapses in federal statutes of limitations	(7.5		)	(67.6		)	—
Tax accounting method changes	—			(65.4		)	—
Release of valuation allowance	—			—			(1.7		)
Domestic production activities	—			—			(12.4		)
Impact of the U.S. Tax Cuts and Jobs Act	—			2.8			289.5
Other	2.9			5.0			(6.0		)
Total (benefit) provision for income taxes	$	69.4		$	(34.2	)	$	505.6

Schedule of Deferred Tax Assets and Liabilities

Significant components of the Company's long-term deferred tax assets and deferred tax liabilities are as follows (in millions):



	As of December 31,
	2019			2018
Deferred tax assets:
Net operating loss carry-forwards	$	27.7		$	12.9
Research and other credit carry-forwards	236.7			220.0
Deferred revenue	40.0			37.7
Share-based compensation	24.3			26.1
Cost sharing adjustment	—			12.2
Reserves and accruals not currently deductible	55.8			62.7
Operating lease liabilities	48.3			—
Other	12.0			13.2
Total deferred tax assets	444.8			384.8
Valuation allowance	(249.4		)	(233.7		)
Deferred tax assets, net of valuation allowance	195.4			151.1
Deferred tax liabilities:
Property and equipment basis differences	(39.2		)	(40.6		)
Purchased intangibles	(27.8		)	(13.7		)
Unremitted foreign earnings	(23.7		)	(26.4		)
Deferred compensation and other	(8.7		)	(8.9		)
Operating lease assets	(41.1		)	—
Total deferred tax liabilities	(140.5		)	(89.6		)
Net deferred tax assets	$	54.9		$	61.5

Reconciliation of Unrecognized Tax Benefits

A reconciliation of the beginning and ending amount of the Company's total gross unrecognized tax benefits was as follows (in millions):



	Years Ended December 31,
	2019			2018			2017
Balance at beginning of year	$	178.1		$	264.5		$	223.1
Tax positions related to current year:
Additions	5.9			4.3			64.6
Tax positions related to prior years:
Additions	0.8			12.7			1.8
Reductions	(3.3		)	(33.8		)	(16.6		)
Settlements	(22.5		)	(2.6		)	(4.0		)
Lapses in statutes of limitations	(7.7		)	(67.0		)	(4.4		)
Balance at end of year	$	151.3		$	178.1		$	264.5