A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- Definition

Amount after tax, before reclassification adjustments of other comprehensive income (loss).

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Amount of tax expense (benefit) allocated to other comprehensive income (loss) before reclassification adjustment from accumulated other comprehensive income (loss).

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Amount after tax of reclassification adjustments of other comprehensive income (loss).

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Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income (loss).

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Amount of stockholders' equity (deficit), net of receivables from officers, directors, owners, and affiliates of the entity, attributable to both the parent and noncontrolling interests. Amount excludes temporary equity. Alternate caption for the concept is permanent equity.

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Comprehensive Income (Loss) - Changes in Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2018
Total Equity
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	$ 1,110.8	$ 1,128.7	$ 1,205.5	$ 1,208.3
Other comprehensive income (loss) before reclassifications, net of taxes of $0	(6.9)
Amounts reclassified from accumulated other comprehensive income (loss), net of taxes of $0	0.6
Other Comprehensive Income (Loss) before Reclassifications, Tax	0.0
Amounts reclassified from accumulated other comprehensive loss, tax	0.0
Accumulated Other Compre- hensive Income (Loss)
Total Equity
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	(55.1)	(48.8)	$ (52.6)	$ (51.9)
Employee Benefit Plans
Total Equity
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	(47.4)	(48.0)
Other comprehensive income (loss) before reclassifications, net of taxes of $0	0.0
Amounts reclassified from accumulated other comprehensive income (loss), net of taxes of $0	0.6
Employee Benefit Plans \| Pension plans \| Qualified plans
Total Equity
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	(46.8)	(47.4)
Employee Benefit Plans \| Post-retirement plans \| Qualified plans
Total Equity
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	0.2	0.2
Employee Benefit Plans \| Non-qualified benefit plans \| Non-qualified plans
Total Equity
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	(0.8)	(0.8)
Interest Rate Swap
Total Equity
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	(7.7)	$ (0.8)
Other comprehensive income (loss) before reclassifications, net of taxes of $0	(6.9)
Amounts reclassified from accumulated other comprehensive income (loss), net of taxes of $0	$ 0.0