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Operating Loss Carryforwards, Not Subject To Expiration

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Operating Loss Carryforwards, Subject To Expiration

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Tax Cuts And Jobs Act Of 2017, Alternative Minimum Tax, Income Tax Benefit

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Tax Cuts And Jobs Act Of 2017, Incomplete Accounting, Change In Tax Rate, Deferred Tax Asset, Provisional Income Tax Expense

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Tax Cuts And Jobs Act Of 2017, Transition Tax For Accumulated Foreign Earnings, Provisional Income Tax Expense

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Unrecognized Tax Benefits That Would Impact Effective Tax Rate, Adjustment To Deferred Tax Assets And Valuation Allowance

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

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The amount of estimated penalties and interest accrued as of the balance sheet date arising from income tax examinations.

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The sum of the amounts of estimated penalties and interest recognized in the period arising from income tax examinations.

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

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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

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Amount of valuation allowance pertaining to the deferred tax asset representing potential future taxable deductions from tax credit carryforwards for which it is more likely than not that a tax benefit will not be realized.

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Amount of undistributed earnings of foreign subsidiaries intended to be permanently reinvested outside the country of domicile.

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Amount of unrecognized tax benefits.

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Income Taxes - Narrative (Details) - USD ($)	12 Months Ended
Income Taxes - Narrative (Details) - USD ($)	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Operating Loss Carryforwards [Line Items]
Federal income tax rates	21.00%	34.00%	34.00%
Operating loss carryforwards, expiring in future	$ 307,400,000
Operating loss carryforwards, carryforward indefinitely	616,200,000
Unrecognized tax benefits	59,800,000	$ 25,600,000	$ 15,700,000	$ 7,900,000
Unrecognized tax benefits that would impact effective tax rate	4,500,000
Unrecognized tax benefits that would impact effective tax rate, adjustment to deferred tax assets and valuation allowance	55,300,000
Penalties and interest accrued	1,300,000
Penalties and interest expense	700,000	200,000	$ 400,000
Undistributed earnings of foreign subsidiaries	0
Estimated reduction in deferred tax assets due to remeasurement		63,100,000
Estimated tax benefit from repealed corporate AMT		1,400,000
Estimated transition tax inclusion		$ 0
Domestic
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	923,600,000
Domestic \| Research Tax Credit Carryforward
Operating Loss Carryforwards [Line Items]
Tax credit carryforward, amount	145,000,000
Tax credit carryforward, valuation allowance	36,100,000
State
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	403,500,000
State \| Research Tax Credit Carryforward
Operating Loss Carryforwards [Line Items]
Tax credit carryforward, amount	76,800,000
Tax credit carryforward, valuation allowance	19,100,000
State \| State Enterprise Tax Credit Carryforward
Operating Loss Carryforwards [Line Items]
Tax credit carryforward, amount	3,700,000
Foreign
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	288,000,000
Operating loss carryforwards, carryforward indefinitely	265,100,000
Operating loss carryforwards, acquired	$ 22,900,000