Business Acquisitions and Dispositions (Details) $ in Millions					3 Months Ended	4 Months Ended	9 Months Ended	12 Months Ended
	Oct. 04, 2022 USD ($)	Dec. 30, 2021 USD ($) acquisition	Mar. 17, 2021 USD ($)	Sep. 03, 2020 USD ($)	Sep. 30, 2022 USD ($)	Dec. 31, 2020 USD ($)	Sep. 30, 2021 acquisition	Dec. 31, 2022 USD ($) acquisition	Dec. 31, 2021 USD ($) acquisition	Dec. 31, 2020 USD ($) acquisition
Business Acquisition [Line Items]
Number of businesses acquired | acquisition		7					4	7	7
Goodwill		$ 138.8				$ 13,338.4		$ 15,946.1	$ 13,476.3	$ 13,338.4
Other identifiable intangibles		104.9
Sedaru, Inc
Business Acquisition [Line Items]
Proceeds from sale of equity method investments			$ 27.1
Equity method investment, realized gain (loss) on disposal			27.1
Sedaru, Inc | Disposal group, disposed of by sale, not discontinued operations | Gatan
Business Acquisition [Line Items]
Income tax expense in connection with sale			$ 5.5
Customer related intangibles
Business Acquisition [Line Items]
Other identifiable intangibles		$ 94.6
Weighted average useful life of finite-lived intangible assets (in years)		12 years 10 months 24 days
Technology
Business Acquisition [Line Items]
Other identifiable intangibles		$ 10.3
Weighted average useful life of finite-lived intangible assets (in years)		5 years 3 months 18 days
Frontline Technologies Parent LLC
Business Acquisition [Line Items]
Aggregate purchase price	$ 3,738.0
Enterprise value, adjusted for cash and the settlement of liabilities, net of tax benefit								3,725.0
Business combination, consideration tax benefit	$ 350.0
Business combination, consideration tax benefit utilized over period	15 years
Goodwill								2,197.6
Other identifiable intangibles								1,918.6
Amortizable intangible assets								1,835.6
Deferred tax assets (liabilities), net								258.0
Deferred tax liabilities								181.0
Goodwill, expected tax deductible amount								1,100.0
Frontline Technologies Parent LLC | Trade names
Business Acquisition [Line Items]
Other identifiable intangibles								83.0
Frontline Technologies Parent LLC | Customer related intangibles
Business Acquisition [Line Items]
Other identifiable intangibles								$ 1,757.0
Weighted average useful life of finite-lived intangible assets (in years)								20 years
Frontline Technologies Parent LLC | Technology
Business Acquisition [Line Items]
Other identifiable intangibles								$ 78.6
Weighted average useful life of finite-lived intangible assets (in years)								5 years
Other acquisitions
Business Acquisition [Line Items]
Number of businesses acquired | acquisition								6		5
Aggregate purchase price									225.9
Goodwill						303.9				$ 303.9
Deferred tax liabilities						612.8		$ 578.8		612.8
Other acquisitions | Trade names
Business Acquisition [Line Items]
Other identifiable intangibles						313.0				313.0
Other acquisitions | Customer related intangibles
Business Acquisition [Line Items]
Other identifiable intangibles						283.7				$ 283.7
Weighted average useful life of finite-lived intangible assets (in years)										16 years
Other acquisitions | Technology
Business Acquisition [Line Items]
Other identifiable intangibles						29.3				$ 29.3
Weighted average useful life of finite-lived intangible assets (in years)										5 years
T I P Technologies Inc And Common Sense Solutions Inc
Business Acquisition [Line Items]
Goodwill					$ 361.5
Other identifiable intangibles					239.3
T I P Technologies Inc And Common Sense Solutions Inc | Trade names
Business Acquisition [Line Items]
Other identifiable intangibles					9.5
T I P Technologies Inc And Common Sense Solutions Inc | Customer related intangibles
Business Acquisition [Line Items]
Other identifiable intangibles					$ 223.4
Weighted average useful life of finite-lived intangible assets (in years)					18 years 2 months 12 days
T I P Technologies Inc And Common Sense Solutions Inc | Technology
Business Acquisition [Line Items]
Other identifiable intangibles					$ 15.9
Weighted average useful life of finite-lived intangible assets (in years)					4 years 10 months 24 days
American LegalNet Inc
Business Acquisition [Line Items]
Percentage of voting interests acquired (as a percent)		100.00%
Vertafore
Business Acquisition [Line Items]
Aggregate purchase price				$ 5,398.6
Goodwill				3,229.1
Other identifiable intangibles				2,660.0		2,540.0				$ 2,540.0
Deferred tax assets (liabilities), net				489.0					$ 120.0
Deferred tax liabilities				$ 638.0
Percentage of voting interests acquired (as a percent)				100.00%
Business acquisition, enterprise value				$ 5,335.0
Purchase price				120.0
Vertafore | Trade names
Business Acquisition [Line Items]
Other identifiable intangibles				$ 120.0
Vertafore | Customer related intangibles
Business Acquisition [Line Items]
Other identifiable intangibles						$ 2,230.0				2,230.0
Weighted average useful life of finite-lived intangible assets (in years)						17 years
Vertafore | Technology
Business Acquisition [Line Items]
Other identifiable intangibles						$ 310.0				$ 310.0
Weighted average useful life of finite-lived intangible assets (in years)						8 years