Income Taxes (Schedule of Income Tax Expense and Effective Tax Rate) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Income Tax Disclosure [Abstract]
Income before income taxes	$ 223,177	$ 196,992	$ 418,268	$ 408,776
Income before incomes taxes, % change	13.00%		2.00%
Income tax expense	$ 72,797	$ 24,643	$ 103,864	$ 49,395
Income tax expense, % change	195.00%		110.00%
Effective tax rate (as a percent)	32.60%	12.50%	24.80%	12.10%
Effective tax rate, % change	20.00%		13.00%

Effective Income Tax Rate Reconciliation, Change Between Current and Prior Period, Percent

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Income (Loss) from Continuing Operations before Income Taxes, Change Between Current and Prior Period, Percent

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Income Tax Expense (Benefit), Change Between Current and Prior Period, Percent

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

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