Earnings (Loss) Per Share - Summary (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	1 Months Ended		3 Months Ended								12 Months Ended
	Feb. 07, 2019		Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2021	Dec. 31, 2020	[1]	Dec. 31, 2019
Earnings Per Share [Abstract]
Net income (loss) attributable to Dun & Bradstreet Holdings, Inc. (Successor) / The Dun & Bradstreet Corporation (Predecessor), basic	$ (75.6)		$ (11.6)	$ 16.6	$ (51.7)	$ (25.0)	$ 1.8	$ (16.3)	$ (208.0)	$ 41.9	$ (71.7)	$ (180.6)		$ (674.1)
Weighted average number of shares outstanding - basic (shares)	37.2	[1]									428.7	367.1		314.5	[1]
Weighted average number of shares outstanding - diluted (shares)	37.2	[1]									428.7	367.1		314.5	[1]
Earnings (loss) per share of common stock:
Basic earnings (loss) per share of common stock attributable to Dun & Bradstreet Holdings, Inc.	$ (2.04)	[1]									$ (0.17)	$ (0.49)		$ (2.14)	[1]
Diluted earnings (loss) per share of common stock attributable to Dun & Bradstreet Holdings, Inc.	$ (2.04)	[1]									$ (0.17)	$ (0.49)		$ (2.14)	[1]

[1] See Note 1 Basis of Presentation and Description of Business for further detail regarding the elimination of the International lag reporting.