Background and Basis of Presentation - Impacts of COVID-19 (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Restructuring Cost and Reserve [Line Items]
Impairment losses	$ 52.3		$ 0.0	$ 52.3	$ 0.0
Restructuring charges from idled assets	2.6		2.0	2.6	2.0
Employee termination benefit costs	0.4		0.0	0.4	0.0
COVID-19 costs	0.4	$ 1.1	$ 0.0	$ 1.5	$ 0.0
Fine Paper Machine
Restructuring Cost and Reserve [Line Items]
Restructuring charges from idled assets	$ 2.6

The aggregate amount of write-downs for impairments recognized during the period for long lived assets held for use (including those held for disposal by means other than sale).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 45
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-URI http://asc.fasb.org/extlink&oid=109226348&loc=d3e2420-110228

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