Segment Information - Schedule of Revenue and Operating Income (Loss) by Segment (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Segment Reporting Information [Line Items]
Revenue		$ 537.3	$ 520.9	$ 1,073.3	$ 1,025.4
Adjusted EBITDA:		200.0	198.3	390.1	384.0
Depreciation and amortization		147.0	152.3	296.4	302.0
Interest expense - net		(41.6)	(47.8)	(88.5)	(96.6)
Benefit (provision) for income taxes		0.1	(43.0)	9.4	(33.2)
Other income (expense) - net		11.2	12.4	1.9	19.2
Equity in net income of affiliates		0.6	0.7	1.3	1.3
Net income (loss) attributable to non-controlling interest		(1.8)	(0.9)	(3.3)	(2.6)
Other incremental or reduced expenses and revenue from the application of purchase accounting		3.9	4.2	7.8	4.9
Equity-based compensation		(15.3)	(7.1)	(26.0)	(14.7)
Restructuring charges		(2.4)	(10.1)	(7.7)	(15.9)
Merger, acquisition and divestiture-related operating costs		(6.9)	(2.0)	(12.0)	(5.1)
Transition costs		(2.0)	(2.9)	(8.9)	(3.9)
Legal expense associated with significant legal and regulatory matters		(0.4)	(0.7)	(0.6)	(10.6)
Asset impairment		(0.2)	(0.5)	(0.2)	(1.5)
Net income (loss) attributable to Dun & Bradstreet Holdings, Inc., Basic		(1.8)	(51.7)	(33.1)	(76.7)
Capital expenditures:		3.4	79.4	7.5	80.7
Additions to computer software and other intangibles:		48.1	34.1	91.7	76.5
Office Building In Jacksonville, FL
Segment Reporting Information [Line Items]
Asset acquisition, purchase price	$ 76.6
In-place lease intangibles	$ 7.1		7.1		7.1
Operating segments
Segment Reporting Information [Line Items]
Depreciation and amortization		23.2	17.4	43.7	32.8
Capital expenditures:		3.4	79.3	7.5	80.6
Additions to computer software and other intangibles:		45.3	33.8	87.4	76.1
Corporate and other
Segment Reporting Information [Line Items]
Revenue		0.0	0.0	0.0	(4.8)
Adjusted EBITDA:		(7.9)	(11.7)	(26.2)	(28.6)
Depreciation and amortization		123.8	134.9	252.7	269.2
Capital expenditures:		0.0	0.1	0.0	0.1
Additions to computer software and other intangibles:		2.8	0.3	4.3	0.4
North America | Operating segments
Segment Reporting Information [Line Items]
Revenue		381.3	357.2	748.6	696.6
Adjusted EBITDA:		161.4	167.4	314.7	318.5
Depreciation and amortization		19.5	14.6	36.7	27.2
Capital expenditures:		2.5	77.7	5.8	78.3
Additions to computer software and other intangibles:		37.5	27.5	73.1	62.4
International | Operating segments
Segment Reporting Information [Line Items]
Revenue		156.0	163.7	324.7	333.6
Adjusted EBITDA:		46.5	42.6	101.6	94.1
Depreciation and amortization		3.7	2.8	7.0	5.6
Capital expenditures:		0.9	1.6	1.7	2.3
Additions to computer software and other intangibles:		$ 7.8	$ 6.3	$ 14.3	$ 13.7