CONSOLIDATED STATEMENTS OF INCOME AND COMPREHENSIVE INCOME (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
CONSOLIDATED STATEMENTS OF INCOME AND COMPREHENSIVE INCOME
Net sales	$ 275,854	$ 267,798	$ 511,459	$ 497,148
Material costs	81,822	79,446	149,167	147,184
Personnel costs	102,755	93,176	199,186	183,129
Other operating expenses	52,741	49,022	98,341	88,680
Depreciation and amortization	12,133	9,510	22,332	18,795
Income from operations	26,403	36,644	42,433	59,360
Interest expense	6,201	7,708	12,299	15,485
Extinguishment of debt		6,645		6,645
Income before taxes	20,202	22,291	30,134	37,230
Provision for income taxes	7,583	8,212	11,518	13,661
Net income	12,619	14,079	18,616	23,569
Comprehensive income	$ 12,619	$ 14,079	$ 18,616	$ 23,569
Basic Per Common Share Data
Net income (in dollars per share)	$ 0.36	$ 0.40	$ 0.53	$ 0.68
Shares used to compute basic per common share amounts (in shares)	35,469,769	34,849,659	35,319,944	34,724,077
Diluted Per Common Share Data
Net income (in dollars per share)	$ 0.35	$ 0.40	$ 0.52	$ 0.67
Shares used to compute diluted per common share amounts (in shares)	35,591,764	35,307,697	35,470,170	35,225,871