Selected Quarterly Financial Data (Unaudited) (Tables)

12 Months Ended

Dec. 31, 2014

Selected Quarterly Financial Information [Abstract]

Schedule of Quarterly Financial Data

	Quarter Ended
	Mar. 31			Jun. 30		Sept. 30		Dec. 31
Fiscal 2014
Net sales	$	209,986		$	223,217	$	233,777	$	223,671
Gross profit		61,581			70,304		74,732		70,662
Net income attributable to common    shareholders		10,202			17,385		19,427		16,665
Earnings per share attributable to common    shareholders
Basic	$	0.22		$	0.37	$	0.41	$	0.35
Diluted		0.21			0.36		0.40		0.34
	Quarter Ended
	Mar. 31			Jun. 30		Sept. 30		Dec. 31
Fiscal 2013
Net sales	$	176,964		$	214,379	$	224,510	$	210,993
Gross profit		46,183			61,293		69,559		60,801
Net income (loss) attributable to common    shareholders		(1,926	)		8,635		13,619		6,204
Earnings (loss) per share attributable to    common shareholders
Basic	$	(0.04	)	$	0.19	$	0.29	$	0.13
Diluted		(0.04	)		0.18		0.28		0.13