Income Taxes (Reconciliation Of Income Taxes To Effective Tax Rate) (Details)	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Taxes [Abstract]
U.S. federal statutory tax rate	35.00%	35.00%	35.00%
Foreign taxes greater (less) than federal statutory rate	(7.00%)	(1.00%)	(2.00%)
Research and development tax credits	(3.00%)	(3.00%)	(2.00%)
Enhanced deduction for certain research and development expenses	(2.00%)	(7.00%)	(8.00%)
State income taxes, net of federal tax benefit	1.00%	1.00%	1.00%
Employee share-based compensation	1.00%	1.00%	1.00%
Change in intercompany prepaid tax asset	1.00%	1.00%	(1.00%)
Change in valuation allowance		(1.00%)
Domestic production activities deduction			(1.00%)
Decrease in unrecognized tax benefits			(10.00%)
Amortization of intangible assets	1.00%
Other	1.00%	1.00%	(1.00%)
Effective tax rate	28.00%	27.00%	12.00%

Effective Income Tax Rate Reconciliation, Change in Intercompany Prepaid Tax Asset

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The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate attributable to deductible research and development expenses.

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EffectiveIncome Tax Rate Reconciliation, Unrecognized Tax Benefits

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

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

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Percentage 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 changes in the valuation allowance for deferred tax assets.

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Percentage 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 applicable to statutory income tax expense (benefit) outside of the country of domicile.

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Percentage 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 applicable to state and local income tax expense (benefit), net of federal tax expense (benefit).

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