Consolidated Statements of Comprehensive Income (Loss) (Parenthetical) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Statement of Comprehensive Income [Abstract]
Change in unrealized gain/losses on cash flow hedges, tax	$ 0.0	$ 0.0	$ 0.0	$ 0.0
Adjustments of and amortization of net actuarial loss and prior service cost, tax	$ (0.2)	$ (0.2)	$ 0.4	$ 0.3

Amount, after reclassification, of tax expense (benefit) for gain (loss) from derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=121641772&loc=d3e640-108580

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration