Quarterly Results Of Operations (Unaudited) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Quarterly Financial Information Disclosure [Abstract]
Net sales	$ 289,351	$ 294,271	$ 321,783	$ 285,377	$ 224,947	$ 250,851	$ 287,192	$ 252,586	$ 1,190,782	$ 1,015,576	$ 901,123	[1]
Gross profit	57,228	62,483	72,012	63,200	47,959	56,126	61,433	47,591	254,923	213,109	168,659
Income before income taxes	17,115	22,941	29,075	25,926	16,100	22,754	25,623	13,470	95,057	77,947	57,802
Net income	$ 11,996	$ 15,488	$ 18,618	$ 16,164	$ 11,077	$ 14,805	$ 15,865	$ 8,372	$ 62,266	$ 50,119	$ 37,340
Net income per common share, Basic	$ 0.50	$ 0.65	$ 0.78	$ 0.68	$ 0.47	$ 0.63	$ 0.68	$ 0.36	$ 2.60	$ 2.15	$ 1.66
Net income per common share, Diluted	$ 0.49	$ 0.64	$ 0.77	$ 0.67	$ 0.46	$ 0.62	$ 0.67	$ 0.36	$ 2.56	$ 2.11	$ 1.64
Stock market price, High	$ 51.69	$ 50.83	$ 54.15	$ 54.20	$ 54.21	$ 45.54	$ 41.25	$ 38.67	$ 54.20	$ 54.21
Stock market price, Low	$ 41.95	$ 41.00	$ 45.80	$ 45.53	$ 45.86	$ 39.60	$ 34.13	$ 33.34	$ 41.00	$ 33.34
Close (at end of quarter)	$ 51.07	$ 42.19	$ 50.01	$ 54.20	$ 51.20	$ 45.54	$ 39.32	$ 36.31	$ 51.07	$ 51.20

[1] (a) Thor Industries, Inc., a customer of the RV Segment, accounted for 33 percent, 34 percent and 37 percent of the Company’s consolidated net sales for the years ended December 31, 2014, 2013 and 2012, respectively. Berkshire Hathaway Inc. (through its subsidiaries Forest River, Inc. and Clayton Homes, Inc.), a customer of both segments, accounted for 28 percent, 28 percent and 27 percent of the Company’s consolidated net sales for the years ended December 31, 2014, 2013 and 2012, respectively. No other customer accounted for more than 10 percent of consolidated net sales in the years ended December 31, 2014, 2013 and 2012.