Goodwill and Other Intangible Assets Components of Other Intangible Assets (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Dec. 31, 2019
Amortizable:
Gross amortized other intangible assets	$ 514,100	$ 514,800
Accumulated Amortization	(136,000)	(126,500)
Net amortized other intangible assets	378,100	388,300
Total other intangible assets, net	$ 820,000	830,300
Non-compete agreements
Amortizable:
Total estimated life	4 years
Gross amortized other intangible assets	$ 2,600	2,600
Dealer/customer related
Amortizable:
Gross amortized other intangible assets	$ 498,900	499,500
Dealer/customer related | Minimum
Amortizable:
Total estimated life	5 years
Dealer/customer related | Maximum
Amortizable:
Total estimated life	20 years
Developed technology
Amortizable:
Gross amortized other intangible assets	$ 12,600	12,700
Developed technology | Minimum
Amortizable:
Total estimated life	5 years
Developed technology | Maximum
Amortizable:
Total estimated life	7 years
Brand/trade names
Non-amortizable—indefinite lived:
Non-amortizable, Net	$ 441,900	$ 442,000