Segments Information - Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Segments Information
Revenue	$ 2,061,807	$ 1,606,745	$ 3,619,588	$ 2,634,018
Intersegment Eliminations
Segments Information
Revenue	(8,530)	(6,248)	(14,828)	(11,760)
Good Sam Services and Plans
Segments Information
Revenue	46,902	44,519	87,773	91,727
Good Sam Services and Plans | Intersegment Eliminations
Segments Information
Revenue	(53)	(173)	(94)	(1,657)
New vehicles
Segments Information
Revenue	1,058,778	898,175	1,880,754	1,395,492
New vehicles | Intersegment Eliminations
Segments Information
Revenue	(2,204)	(2,070)	(4,003)	(3,149)
Used vehicles
Segments Information
Revenue	460,137	274,910	754,394	481,575
Used vehicles | Intersegment Eliminations
Segments Information
Revenue	(1,080)	(789)	(1,852)	(1,357)
Products, service and other
Segments Information
Revenue	305,554	231,172	556,824	403,795
Products, service and other | Intersegment Eliminations
Segments Information
Revenue	(573)	(340)	(893)	(729)
Finance and insurance, net
Segments Information
Revenue	177,685	147,318	315,939	239,774
Finance and insurance, net | Intersegment Eliminations
Segments Information
Revenue	(4,620)	(2,876)	(7,986)	(4,868)
Good Sam Club
Segments Information
Revenue	12,751	10,651	23,904	21,655
Good Sam Services and Plans | Operating Segments
Segments Information
Revenue	46,955	44,692	87,867	93,384
Good Sam Services and Plans | Good Sam Services and Plans | Operating Segments
Segments Information
Revenue	46,955	44,692	87,867	93,384
RV and Outdoor Retail
Segments Information
Revenue	2,014,905	1,562,226	3,531,815	2,542,291
RV and Outdoor Retail | Operating Segments
Segments Information
Revenue	2,023,382	1,568,301	3,546,549	2,552,394
RV and Outdoor Retail | New vehicles
Segments Information
Revenue	1,058,778	898,175	1,880,754	1,395,492
RV and Outdoor Retail | New vehicles | Operating Segments
Segments Information
Revenue	1,060,982	900,245	1,884,757	1,398,641
RV and Outdoor Retail | Used vehicles
Segments Information
Revenue	460,137	274,910	754,394	481,575
RV and Outdoor Retail | Used vehicles | Operating Segments
Segments Information
Revenue	461,217	275,699	756,246	482,932
RV and Outdoor Retail | Products, service and other
Segments Information
Revenue	305,554	231,172	556,824	403,795
RV and Outdoor Retail | Products, service and other | Operating Segments
Segments Information
Revenue	306,127	231,512	557,717	404,524
RV and Outdoor Retail | Finance and insurance, net
Segments Information
Revenue	177,685	147,318	315,939	239,774
RV and Outdoor Retail | Finance and insurance, net | Operating Segments
Segments Information
Revenue	182,305	150,194	323,925	244,642
RV and Outdoor Retail | Good Sam Club
Segments Information
Revenue	12,751	10,651	23,904	21,655
RV and Outdoor Retail | Good Sam Club | Operating Segments
Segments Information
Revenue	$ 12,751	$ 10,651	$ 23,904	$ 21,655