Unaudited Condensed Consolidated Statements Of Cash Flows - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019
CASH PROVIDED BY (USED IN) OPERATING ACTIVITIES:
Net income	$ 47.5	$ 192.8
Adjustments to reconcile net income to net cash provided by operating activities:
Loss from discontinued operations	0.2	0.3
Depreciation and amortization	97.2	88.5
Amortization of debt issuance costs and accretion of debt discounts	2.3	2.6
Stock-based compensation expense	15.7	18.6
Deferred income tax provision	(17.1)	2.0
Net gain related to business/property dispositions	(1.5)	(12.7)
Goodwill impairment	318.3	0.0
Franchise rights impairment	57.5	9.6
Non-cash impairment charges	8.6	1.3
Unrealized gain on equity instrument	(214.7)	0.0
Other	3.8	(1.7)
(Increase) decrease, net of effects from business acquisitions and divestitures:
Receivables	244.6	192.3
Inventory	873.3	81.3
Other assets	75.1	22.1
Increase (decrease), net of effects from business acquisitions and divestitures:
Vehicle floorplan payable - trade, net	(621.5)	(102.4)
Accounts payable	(25.5)	(40.3)
Other liabilities	30.5	(28.8)
Net cash provided by continuing operations	894.3	425.5
Net cash provided by discontinued operations	0.0	0.0
Net cash provided by operating activities	894.3	425.5
CASH PROVIDED BY (USED IN) INVESTING ACTIVITIES:
Purchases of property and equipment	(75.3)	(122.7)
Proceeds from assets held for sale	0.0	4.2
Insurance recoveries on property and equipment	1.5	3.3
Cash received from business divestitures, net of cash relinquished	0.0	22.3
Cash used in business acquisitions, net of cash acquired	(0.4)	(4.3)
Investment in equity security	(50.0)	0.0
Other	(0.5)	0.4
Net cash used in continuing operations	(124.7)	(96.8)
Net cash used in discontinued operations	0.0	0.0
Net cash used in investing activities	(124.7)	(96.8)
CASH PROVIDED BY (USED IN) FINANCING ACTIVITIES:
Repurchases of common stock	(80.0)	(44.7)
Proceeds from 4.75% Senior Notes due 2030	497.4	0.0
Payment of 5.5% Senior Notes due 2020	(350.0)	0.0
Proceeds from revolving credit facility	1,100.0	0.0
Payments of revolving credit facility	(1,100.0)	0.0
Net payments of commercial paper	(170.0)	(160.0)
Payment of debt issuance costs	(10.5)	0.0
Net payments of vehicle floorplan payable - non-trade	(431.4)	(117.3)
Payments of other debt obligations	(3.1)	(4.4)
Proceeds from the exercise of stock options	1.0	3.2
Payments of tax withholdings for stock-based awards	(8.1)	(3.0)
Net cash used in continuing operations	(554.7)	(326.2)
Net cash used in discontinued operations	0.0	0.0
Net cash used in financing activities	(554.7)	(326.2)
INCREASE IN CASH, CASH EQUIVALENTS, AND RESTRICTED CASH	214.9	2.5
CASH, CASH EQUIVALENTS, AND RESTRICTED CASH at beginning of period	42.5	49.4
CASH, CASH EQUIVALENTS, AND RESTRICTED CASH at end of period	$ 257.4	$ 51.9