Effective Income Tax Rate Reconciliation, Expiration of Net Operating Losses

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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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Effective income tax rate reconciliation, loss from business combination

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

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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, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Federal statutory income tax rate (in dollars per share)									35.00%	35.00%	35.00%
Reconciliation between statutory rate and income tax provision
U.S. federal tax at 35%									$ 106,354	$ 75,305	$ 23,769
State taxes, net of federal benefit									2,193	836	2,622
Foreign income taxed at different rates									(51,412)	(17,907)	(11,756)
Foreign exchange (loss) gain									29,756	(1,127)	(5,680)
Change in valuation allowance									(4,703)	(7,362)	18,259
Adjustments related to prior years									3,329	(2,648)	(912)
U.S. tax reform (the Tax Act)									(41,554)	0	0
Income tax credits generated									(7,296)	(40,301)	(1,919)
Repatriation of foreign earnings and profits									719	25,604	91
Expiration of net operating losses and credits									166	15,092	74
Non-deductible loss on acquisition of J-Devices (Note 3)									0	0	4,725
Other									1,430	361	(1,238)
Income tax expense	$ (12,782)	$ 18,752	$ 32,573	$ 439	$ 18,534	$ 24,086	$ 3,360	$ 1,873	$ 38,982	$ 47,853	$ 28,035