Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Income Tax Disclosure [Abstract]
Effective income tax rate, percent	30.80%	32.50%	26.50%	32.20%
Decrease in valuation allowance		$ 8.1		$ 8.1
Increase (decrease) in unrecognized tax benefits	$ 4.4	$ 7.7	$ (5.6)	$ 9.7
Settlement agreement (as defined therein) with taxing authority	1,490.0		1,490.0
Decrease in liability from prior year	525.0		$ 525.0
Tax expense	$ 0.4

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319

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The amount the liability recorded for the income tax examination increased or decreased in the current year/accounting period.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
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The amount of the additional liability or refund received or expected based on a final settlement with a taxing authority.

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Amount of other income tax expense (benefit).

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 9
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32639-109319

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(h)(1)(Note 1))
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Amount of increase (decrease) in unrecognized tax benefits attributable to uncertain tax positions taken in tax returns.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset.

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