Income Taxes (Narrative) (Details) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Income Tax Disclosure [Abstract]
U.S. statutory tax rate	21.00%		35.00%
Federal income tax expense	$ 25.7	$ 44.3
Foreign income tax expense (benefit)	$ (7.8)	$ 2.1

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

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Amount of current and deferred federal income tax expense (benefit) attributable to income (loss) from continuing operations.

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-Publisher FASB
-Name Accounting Standards Codification
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Amount of current and deferred foreign income tax expense (benefit) attributable to income (loss) from continuing operations.

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