Other Charges, Net - Restructuring Plans (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Restructuring charges
Restructuring expenses	$ 15.8	$ 1.4	$ 9.4
Gain on the sale of a building		7.7
Other programs
Restructuring charges
Restructuring expenses	15.8	1.4	9.4
Cost of revenues \| Other programs
Restructuring charges
Restructuring expenses	3.8	5.3	2.6
Other charges, net \| Other programs
Restructuring charges
Restructuring expenses	$ 12.0	$ (3.9)	$ 6.8

Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration