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, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Reconciliation between statutory rate and income tax provision
U.S. federal statutory income tax rate									$ 33,560	$ 39,021	$ 107,623
State taxes, net of federal benefit									293	1,677	2,624
Foreign income taxed at different rates									(10,600)	6,340	(51,661)
Foreign exchange (loss) gain									84	(3,797)	29,756
Change in valuation allowance	$ (3,800)			$ 14,900					18,374	(12,662)	(6,763)
Adjustments related to prior years									(3,190)	1,898	(558)
U.S. tax reform (the Tax Act)					$ (41,600)				0	22,284	(41,554)
Income tax credits generated									(9,006)	(18,106)	(7,296)
Foreign earnings and profits									3,360	387	719
Foreign derived intangible income									(3,195)	0	0
Expiration of net operating losses and credits									3,084	19,462	166
Settlements and changes in uncertain tax positions									3,256	(1,230)	5,305
Other									1,162	976	1,430
Income tax expense	$ 764	$ 9,141	$ 5,897	$ 21,380	$ 28,812	$ 14,326	$ 10,631	$ 2,481	$ 37,182	$ 56,250	$ 39,791