Acquisitions and Dispositions of Businesses (Assets Acquired and Liabilities Assumed) (Details 1) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Business Acquisition [Line Items]
Goodwill	$ 1,345,393	$ 1,297,712
Floor plan payables	(25,800)
Series of Individually Immaterial Business Acquisitions [Member]
Business Acquisition [Line Items]
Accounts receivable	4,697	2,344
Inventory	31,750	1,268
Property, plant and equipment	52,577	1,518
Lease Right-of-Use Assets	100,933	0
Goodwill	63,387	41,840
Indefinite-lived intangible assets	46,900	0
Amortized intangible assets	21,291	78,427
Other assets	8,352	5,198
Floor plan payables	(25,755)	0
Other liabilities	(38,828)	(7,678)
Deferred income tax liability	(2,191)	(4,900)
Current and noncurrent lease liabilities	(97,996)	0
Noncontrolling interest	(530)	0
Aggregate purchase price, net of cash acquired	$ 164,587	$ 118,017