Selected Quarterly Financial Data (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Selected Quarterly Financial Information [Abstract]
Net sales	$ 214,381	$ 208,888	$ 219,453	$ 206,182	$ 223,671	$ 233,777	$ 223,217	$ 209,986	$ 848,904	$ 890,651	$ 826,846
Gross profit	53,597	61,636	69,437	63,913	70,662	74,732	70,304	61,581	248,583	277,279	237,836
Net income attributable to common shareholders	$ (4,773)	$ 2,837	$ 15,078	$ 11,132	$ 16,665	$ 19,427	$ 17,385	$ 10,202	$ 24,274	$ 63,678	$ 26,532
Earnings per share attributable to common shareholders
Basic	$ (0.10)	$ 0.06	$ 0.31	$ 0.23	$ 0.35	$ 0.41	$ 0.37	$ 0.22	$ 0.50	$ 1.35	$ 0.57
Diluted	$ (0.10)	$ 0.06	$ 0.31	$ 0.23	$ 0.34	$ 0.40	$ 0.36	$ 0.21	$ 0.49	$ 1.31	$ 0.56