Consolidated Statements of Cash Flows - USD ($) $ in Millions		1 Months Ended		3 Months Ended							12 Months Ended
		Feb. 07, 2019		Dec. 31, 2021	Mar. 31, 2021		Dec. 31, 2020		Mar. 31, 2020		Dec. 31, 2021		Dec. 31, 2020	[2]	Dec. 31, 2019		Dec. 31, 2018
Cash flows provided by (used in) operating activities:
Net income (loss)		$ (74.8)	[1]	$ (10.0)	$ (23.3)		$ 3.1		$ 74.3		$ (65.9)		$ (111.6)	[1]	$ (553.7)	[1],[2]
Reconciliation of net income (loss) to net cash provided by (used in) operating activities:
Depreciation and amortization		11.1									615.9		537.8		487.1	[2]
Amortization of unrecognized pension loss (gain)		3.8									1.9		(0.5)		0.0	[2]
Payments for debt early redemption premiums reclassified to financing cash flows		0.0									29.5		50.1		0.0	[2]
Amortization and write off of deferred debt issuance costs		3.3									31.2		45.0		23.2	[2]
Pension settlement charge		85.8									0.0		0.6		0.0	[2]
Pension settlement payments		(190.5)									0.0		0.0		(105.9)	[2]
Income tax benefit from stock-based awards		10.3									0.0		0.0		0.0	[2]
Equity-based compensation expense		11.7									33.3		45.1		68.0	[2]
Restructuring charge		0.1	[1]								25.1		37.3	[1]	52.3	[1],[2]
Restructuring payments		(2.1)									(20.6)		(16.5)		(39.8)	[2]
Change in fair value of make-whole derivative liability		0.0							(69.8)		0.0		32.8		172.4	[2]
Changes in deferred income taxes		(33.2)									(77.4)		(99.6)		(137.7)	[2]
Changes in prepaid and accrued income taxes		(8.1)									5.1		(129.7)		(15.1)	[2]
Changes in operating assets and liabilities:
(Increase) decrease in accounts receivable		16.3									(13.7)		(45.1)		(16.5)	[2]
(Increase) decrease in prepaid taxes, other prepaids and other current assets	[3]	(1.2)									63.2		(28.9)		6.0	[2]
Increase (decrease) in deferred revenue	[3]	20.8									16.5		8.1		68.7	[2]
Increase (decrease) in accounts payable	[3]	37.8									(0.1)		9.1		(25.1)	[2]
Increase (decrease) in accrued liabilities	[3]	(39.7)									(2.3)		(20.3)		(22.8)	[2]
Increase (decrease) in other accrued and current liabilities	[3]	25.1									(24.3)		(18.1)		42.5	[2]
(Increase) decrease in other long-term assets	[3]	(96.0)									(34.2)		(49.7)		(40.4)	[2]
Increase (decrease) in long-term liabilities	[3]	154.6									(84.4)		(39.2)		(47.5)	[2]
Net, other non-cash adjustments		(0.5)									4.9		(1.2)		13.8	[2],[4]
Net cash provided by (used in) operating activities		(65.4)									503.7		205.5		(70.5)	[2]
Cash flows provided by (used in) investing activities:
Acquisitions of businesses, net of cash acquired		0.0									(844.8)		(20.6)		(6,078.0)	[2]
Cash settlements of foreign currency contracts		0.0									22.3		7.7		(9.4)	[2]
Payments for real estate purchase		0.0									(76.6)		0.0		0.0	[2]
Capital expenditures		(0.2)									(9.7)		(7.8)		(12.4)	[2]
Additions to computer software and other intangibles		(5.1)									(170.7)		(115.2)		(57.4)	[2]
Other investing activities, net		0.0									0.8		2.1		0.5	[2]
Net cash provided by (used in) investing activities		(5.3)									(1,078.7)		(133.8)		(6,156.7)	[2]
Cash flows provided by (used in) financing activities:
Proceeds from issuance of common stock in the IPO transaction and Private Placement, net		0.0									0.0	[5]	2,248.2	[3],[5]	0.0	[2],[3],[5]
Proceeds from investors		0.0									0.0		0.0				$ 3,176.8	[2]
Payment for the redemption of Cumulative Series A Preferred Stock		0.0									0.0		(1,067.9)		0.0	[2]
Payment for make-whole liability		0.0									0.0		(205.2)		0.0	[2]
Payment for debt early redemption premiums		0.0									(29.5)		(50.1)		0.0	[2]
Payments of dividends		0.0									0.0		(64.1)		(96.1)	[2]
Proceeds from issuance of Successor's Senior Notes		0.0									460.0		0.0		1,450.0	[2]
Retirement of Predecessor's Senior Notes		0.0									0.0		0.0		(625.1)	[2]
Payments of borrowings on Successor’s Senior Notes		0.0									(450.0)		(580.0)		0.0	[2]
Payment of debt issuance costs		0.0									(9.5)		(2.5)		(122.6)	[2]
Other financing activities, net		(0.1)									(2.8)		(7.8)		(3.7)	[2]
Net cash provided by (used in) financing activities		96.9									400.1		188.6		6,321.7	[2]
Effect of exchange rate changes on cash and cash equivalents		1.2									(0.3)		7.6		(10.1)	[2]
Increase (decrease) in cash and cash equivalents		27.4									(175.2)		267.9		84.4	[2]
Cash and Cash Equivalents, Beginning of Period		90.2			$ 352.3	[2]			$ 84.4	[2]	352.3	[2]	84.4		90.2
Cash and Cash Equivalents, End of Period		117.6		177.1			352.3	[2]			177.1		352.3		84.4	[2]	$ 90.2
Cash Paid for:
Income taxes payment (refund), net		3.4									12.7		116.9		34.3	[2]
Interest		2.4									191.8		249.0		237.8	[2]
Noncash Investing and Financing activities:
Fair value of acquired assets		0.0									1,447.4		21.6		9,524.1	[2]
Cash paid for acquired businesses		0.0									(882.1)		(21.2)		(5,558.2)	[2]
Unpaid purchase price accrued in "Other accrued and current liabilities"		0.0									(6.9)		0.0		0.0	[2]
Assumed liabilities from acquired businesses including non-controlling interest		0.0									399.5		0.4		3,965.9	[2]
Noncash additions to computer software		0.0									7.9		0.0		0.0	[2]
Noncash additions to property, plant and equipment		0.0									1.7		2.0		0.0	[2]
Eyeota/NetWise And Bisnode
Noncash Investing and Financing activities:
Cash paid for acquired businesses		0.0		$ (158.9)			$ 0.0	[2]			(158.9)		0.0		0.0	[2]
Predecessor Credit Facility
Cash flows provided by (used in) financing activities:
Proceeds from borrowings on lines of credit		167.0									314.1		407.2		228.3	[2]
Payments of borrowings on lines of credit		(70.0)									(154.1)		(407.2)		(228.3)	[2]
Successor Term Loan Facility
Cash flows provided by (used in) financing activities:
Proceeds from borrowings on lines of credit		0.0									300.0		0.0		2,479.4	[2]
Bridge Loan
Cash flows provided by (used in) financing activities:
Proceeds from borrowings on lines of credit		0.0									0.0		(63.0)		63.0	[2]
Payments of borrowings on lines of credit		$ 0.0									$ (28.1)		$ (19.0)		$ 0.0	[2]

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

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

[3] Net of IPO offering costs of $132.8 million of which $131.9 million was paid by proceeds raised from the offering (see Note 1) and $0.9 million was paid prior to the IPO and Private Placement.

[4] Other noncash adjustments for the period from January 1, 2019 to December 31, 2019 (Successor) are primarily related to non-cash foreign exchange adjustments.

[5] ) Net of IPO offering costs of $132.8 million of which $131.9 million was paid by proceeds raised from the offering (see Note 1) and $0.9 million was paid prior to the IPO and Private Placement.