Income Taxes (Reconciliation Of Effective Income Tax Rate) (Details)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Examination [Line Items]
Expected federal income tax rate	21.00%	21.00%	35.00%
State income taxes, net of federal tax benefit	(15.50%)	(3.80%)	5.70%
Foreign tax rate differential and credits	26.00%	7.60%	66.40%
Unbenefited foreign losses	(0.50%)	(5.50%)	0.00%
Tax reserve	0.30%	(1.30%)	(27.00%)
GILTI	(3.90%)	20.70%
Rate Change	5.90%	0.00%	(13.90%)
Intercompany financing	30.40%	(12.70%)	(17.80%)
Effective Income Tax Rate Reconciliation, Tax Settlement, Foreign, Percent		(45.60%)
Foreign-derived intangible income (FDII)	10.70%	0.10%	0.00%
Prior period adjustment	44.10%	4.30%	(0.60%)
Equity Compensation	0.00%	0.00%	(113.90%)
Other, net	(16.00%)	(0.80%)	3.90%
Effective Income Tax Rate Reconciliation, Tax Expense (Benefit), Share-based Payment Arrangement, Percent	(10.80%)	(4.20%)	(2.70%)
Effective tax rate	(145.40%)	(39.50%)	(195.70%)
State and Local Jurisdiction [Member]
Income Tax Examination [Line Items]
US permanent differences	(1.60%)	(1.00%)	22.70%
Domestic Tax Authority [Member]
Income Tax Examination [Line Items]
Dispositions	(227.00%)	0.00%	4.70%

Effective Income Tax Rate Reconciliation, Income from Earnout, Percent

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Effective Income Tax Rate Reconciliation, Tax Cut and Jobs Act 2017, Global Intangible Low-Taxed Income, Percent

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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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