Other Assets and Liabilities - Other Non-Current Liabilities (Details) - USD ($) $ in Millions	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Deferred revenue - long term	$ 13.8		$ 14.6
U.S. tax liability associated with the 2017 Act	44.6		49.8
Long-term lease liability	67.5		62.5
Other	10.8		8.6
Total	136.7		$ 135.5	[1]
China
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term lease liability related to a new lease and a lease modified during period		$ 3.2
Bisnode
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term lease liability related to a new lease and a lease modified during period	$ 18.2

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