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Income tax expense benefit recorded due to provisions of CARES Act and U.S and Foreign tax legislation changes.

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Represents the number of entities newly classified as held for sale.

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Represents the number of franchises disposed of by the entity during the period.

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Face (par) amount of debt instrument at time of issuance.

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Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

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Contractual interest rate for funds borrowed, under the debt agreement.

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The cash outflow from the repayment of long-term borrowing where a lender is placed in a lien position behind debt having a higher priority of repayment (senior) in case of liquidation of the entity's assets before its maturity.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Interim Financial Statements - Fair Value, Assets Held For Sale, Discontinued Operations (Details) $ in Millions		3 Months Ended	9 Months Ended
	Oct. 01, 2020 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2020 USD ($) item entity	Sep. 30, 2019 entity	Aug. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Fair Value of Financial Instruments
Debt instrument, Carrying Value		$ 2,301.7	$ 2,301.7			$ 2,360.3
Repayments of senior subordinated notes		300.0	$ 300.0
Assets Held for Sale and Discontinued Operations
Number of entities newly classified as held for sale \| entity			0	0
Income Taxes
Income tax expense benefit recorded due to provisions of CARES Act		$ (15.4)
5.75% senior subordinated notes due 2022
Fair Value of Financial Instruments
Interest rate (as a percent)	5.75%	5.75%	5.75%			5.75%
Debt instrument, Carrying Value		$ 550.0	$ 550.0			$ 547.6
Debt instrument, Fair Value		550.3	550.3			$ 556.7
Redemption of debt	$ 550.0
Principal amount		$ 550.0	$ 550.0
5.375% senior subordinated notes due 2024
Fair Value of Financial Instruments
Interest rate (as a percent)		5.375%	5.375%			5.375%
Debt instrument, Carrying Value		$ 298.4	$ 298.4			$ 298.0
Debt instrument, Fair Value		304.5	304.5			$ 306.7
Principal amount		$ 300.0	$ 300.0
3.50% senior subordinated notes due 2025
Fair Value of Financial Instruments
Interest rate (as a percent)		3.50%	3.50%		3.50%
Debt instrument, Carrying Value		$ 542.9	$ 542.9
Debt instrument, Fair Value		541.9	541.9
Principal amount		$ 550.0	$ 550.0		$ 550.0
5.50% senior subordinated notes due 2026
Fair Value of Financial Instruments
Interest rate (as a percent)		5.50%	5.50%			5.50%
Debt instrument, Carrying Value		$ 496.2	$ 496.2			$ 495.7
Debt instrument, Fair Value		511.9	511.9			$ 521.7
Principal amount		$ 500.0	$ 500.0
3.75% senior subordinated notes redeemed August 15, 2020
Fair Value of Financial Instruments
Interest rate (as a percent)		3.75%	3.75%			3.75%
Debt instrument, Carrying Value						$ 299.2
Mortgage facilities
Fair Value of Financial Instruments
Debt instrument, Carrying Value		$ 333.8	$ 333.8			423.2
Debt instrument, Fair Value		$ 354.8	$ 354.8			$ 430.9
Retail Automotive Franchise
Disposals
Number of franchises disposed \| item			10