Segment Reporting (Disaggregation of Revenue) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Disaggregation of Revenue [Line Items]
Net sales	$ 1,644,568	$ 1,000,258
OEM Segment
Disaggregation of Revenue [Line Items]
Net sales	1,396,582	816,250
Travel trailers and fifth-wheels
Disaggregation of Revenue [Line Items]
Net sales	953,226	503,016
Motorhomes
Disaggregation of Revenue [Line Items]
Net sales	87,254	62,593
Adjacent industries OEMs
Disaggregation of Revenue [Line Items]
Net sales	356,102	250,641
Aftermarket Segment
Disaggregation of Revenue [Line Items]
Net sales	247,986	184,008
Chassis, chassis parts and slide-out mechanisms | OEM Segment
Disaggregation of Revenue [Line Items]
Net sales	559,720	287,061
Windows and doors | OEM Segment
Disaggregation of Revenue [Line Items]
Net sales	330,358	249,920
Furniture and mattresses | OEM Segment
Disaggregation of Revenue [Line Items]
Net sales	242,226	155,244
Axles and suspension solutions | OEM Segment
Disaggregation of Revenue [Line Items]
Net sales	97,045	55,122
Other | OEM Segment
Disaggregation of Revenue [Line Items]
Net sales	167,233	68,903
U.S.
Disaggregation of Revenue [Line Items]
Net sales	1,539,596	909,051
U.S. | OEM Segment
Disaggregation of Revenue [Line Items]
Net sales	1,309,429	737,641
U.S. | Travel trailers and fifth-wheels
Disaggregation of Revenue [Line Items]
Net sales	937,635	486,542
U.S. | Motorhomes
Disaggregation of Revenue [Line Items]
Net sales	60,146	39,417
U.S. | Adjacent industries OEMs
Disaggregation of Revenue [Line Items]
Net sales	311,648	211,682
U.S. | Aftermarket Segment
Disaggregation of Revenue [Line Items]
Net sales	230,167	171,410
International
Disaggregation of Revenue [Line Items]
Net sales	104,972	91,207
International | OEM Segment
Disaggregation of Revenue [Line Items]
Net sales	87,153	78,609
International | Travel trailers and fifth-wheels
Disaggregation of Revenue [Line Items]
Net sales	15,591	16,474
International | Motorhomes
Disaggregation of Revenue [Line Items]
Net sales	27,108	23,176
International | Adjacent industries OEMs
Disaggregation of Revenue [Line Items]
Net sales	44,454	38,959
International | Aftermarket Segment
Disaggregation of Revenue [Line Items]
Net sales	$ 17,819	$ 12,598