Unaudited Quarterly Financial Data Unaudited Quarterly Financial Data (Tables)

12 Months Ended

Dec. 31, 2015

Quarterly Financial Data [Abstract]

Schedule of Quarterly Financial Information [Table Text Block]

The following tables summarize the consolidated quarterly results of operations for 2015 and 2014:

	2015
(in thousands, except per share amounts)	First Quarter			Second Quarter		Third Quarter		Fourth Quarter
Net sales	$	292,826		$	357,287	$	416,471	$	510,162
Gross profit	66,697			83,818		97,101		113,794
Net (loss) income	(3,561		)	2,125		4,047		(7,442		)
Basic (loss) income per share	$	(0.09	)	$	0.05	$	0.10	$	(0.16	)
Diluted (loss) income per share	$	(0.09	)	$	0.05	$	0.10	$	(0.16	)

	2014
(in thousands, except per share amounts)	First Quarter			Second Quarter		Third Quarter		Fourth Quarter
Net sales	$	289,716		$	351,620	$	358,314	$	311,848
Gross profit	61,819			79,491		81,642		72,122
Net (loss) income	(1,674		)	84,224		7,532		3,950
Basic (loss) income per share	$	(0.04	)	$	2.17	$	0.19	$	0.10
Diluted (loss) income per share	$	(0.04	)	$	2.14	$	0.19	$	0.10