Effective Income Tax Rate Reconciliation, Expiration of Net Operating Losses

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Effective Income Tax Rate Reconciliation, Foreign Derived Intangible Income

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Effective Income Tax Rate Reconciliation, Tax Cuts and Jobs Act of 2017, Incomplete Accounting, Provisional Income Tax Expense (Benefit)

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The portion of the difference between total income tax expense or benefit as reported in the Income Statement and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations that is attributable to gains or losses on foreign exchange.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to increase (decrease) in the valuation allowance for deferred tax assets.

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to revisions of previously reported income tax expense (benefit).

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to tax credits. Including, but not limited to, research credit, foreign tax credit, investment tax credit, and other tax credits.

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Income Taxes (Reconciliation of effective tax rate) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Reconciliation between statutory rate and income tax provision
U.S. federal statutory income tax rate									$ 81,203	$ 33,560	$ 39,021
State taxes, net of federal benefit									346	293	1,677
Foreign income taxed at different rates									(27,988)	(10,600)	6,340
Foreign exchange (loss) gain									6,710	84	(3,797)
Change in valuation allowance	$ (20,200)				$ (3,800)			$ 14,900	(15,624)	18,374	(12,662)
Adjustments related to prior years									(2,575)	(3,190)	1,898
U.S. tax reform (the Tax Act)									0	0	22,284
Income tax credits generated									(21,525)	(9,006)	(18,106)
Foreign earnings and profits									23,853	3,360	387
Foreign derived intangible income									(6,339)	(3,195)	0
Expiration of net operating losses and credits									144	3,084	19,462
Settlements and changes in uncertain tax positions									6,801	3,256	(1,230)
Other									1,177	1,162	976
Income tax expense	$ 12,679	$ 15,753	$ 12,905	$ 4,846	$ 764	$ 9,141	$ 5,897	$ 21,380	$ 46,183	$ 37,182	$ 56,250