Quarterly Financial Data (Unaudited) (Tables)

12 Months Ended

Dec. 31, 2012

Quarterly Financial Information Disclosure [Abstract]

Unaudited quarterly results of operations

The table below summarizes the unaudited quarterly results of operations for the past two years (in thousands, except per share data):

	Quarter
	2012									2011
	First		Second		Third		Fourth			First			Second		Third		Fourth
Net sales	$	361,954	$	757,175	$	528,027	$	306,818		$	312,889		$	706,423	$	503,584	$	270,422
Gross profit	104,563		222,405		151,501		88,938			91,410			211,439		147,906		80,835
Net income (loss)	3,651		64,943		21,375		(7,997		)	(638		)	58,577		24,169		(10,115		)
Earnings (loss) per share:
Basic	$	0.08	$	1.38	$	0.46	$	(0.17	)	$	(0.01	)	$	1.21	$	0.50	$	(0.21	)
Diluted	$	0.08	$	1.34	$	0.45	$	(0.17	)	$	(0.01	)	$	1.19	$	0.50	$	(0.21	)