Other Assets and Liabilities - Other Non-Current Assets (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Dec. 31, 2020
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Right of use assets	$ 86.2	$ 64.8
Prepaid pension assets	4.4	4.3
Investments	26.4	27.3
Other non-current assets	20.7	16.2
Total	137.7	$ 112.6	[1]
China
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Right-of-use assets related to a new lease and a lease modified during period	3.8
Bisnode
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Right-of-use assets related to a new lease and a lease modified during period	26.7
Lease expense	$ 1.9

[1] See discussion in Note 1 - Basis of Presentation for further detail regarding the elimination of the International lag reporting.