Quarterly Financial Information (Unaudited) (Details) (USD $) In Thousands, except 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	$ 1,578,929	$ 1,569,757	$ 1,517,375	$ 1,312,800	$ 1,421,641	$ 1,486,459	$ 1,468,119	$ 1,282,922	$ 5,978,861	$ 5,659,141	$ 5,413,281
Gross margin	292,613	294,535	281,942	249,457	266,696	277,663	263,965	235,832	1,118,547	1,044,156	1,018,362
Net income attributable to the Company	$ 16,599	$ 30,464	$ 29,044	$ 11,321	$ 22,593	$ 28,633	$ 21,891	$ 7,946	$ 87,428	$ 81,063	$ 86,291
Net income attributable to the Company per share of common stock (usd per share)	$ 1.05	$ 1.93	$ 1.83	$ 0.71	$ 1.42	$ 1.80	$ 1.37	$ 0.50	$ 5.52	$ 5.09	$ 5.40
Common stock dividend declared, percent										2.50%	20.00%
Average common shares outstanding by quarter					15,493,506	15,507,191	15,577,599	15,634,284	15,847,690	15,935,751	15,969,060