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Amount of deferred tax liability attributable to taxable temporary differences assumed at the acquisition date.

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Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition.

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Acquisitions, Goodwill, and Other Intangible Assets (Allocation of Acquired Intangible Assets) (Details) - DBRS [Member] - USD ($) $ in Millions		12 Months Ended
	Jul. 02, 2019	Dec. 31, 2019
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities	$ 66.6
Finite-lived Intangible Assets Acquired	284.1
Customer-related intangible assets [Member]
Business Acquisition [Line Items]
Weighted Average Useful Life (years)		10 years
Customer-related assets [Member]
Business Acquisition [Line Items]
Finite-lived Intangible Assets Acquired	219.1
Technology-based assets [Member]
Business Acquisition [Line Items]
Finite-lived Intangible Assets Acquired	29.4
Weighted Average Useful Life (years)		5 years
Trademarks [Member]
Business Acquisition [Line Items]
Finite-lived Intangible Assets Acquired	$ 35.6
Intellectual property (trademarks and trade names) [Member]
Business Acquisition [Line Items]
Weighted Average Useful Life (years)		7 years