CONSOLIDATED STATEMENTS OF INCOME AND COMPREHENSIVE INCOME (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Net sales	$ 243,503	$ 235,261	$ 713,349	$ 670,451
Cost of goods sold - materials	73,109	69,362	210,107	195,984
Personnel costs	84,135	82,127	251,189	242,030
Other operating expenses	42,177	44,394	135,566	126,387
Relocation expenses		272		689
Depreciation and amortization	8,709	7,864	25,432	22,852
Income from operations	35,373	31,242	91,055	82,509
Interest expense, net	7,751	7,796	23,212	23,966
Income before taxes	27,622	23,446	67,843	58,543
Provision for income taxes	10,278	8,034	25,558	21,487
Net income	17,344	15,412	42,285	37,056
Comprehensive income	$ 17,344	$ 15,412	$ 42,285	$ 37,056
Basic Per Common Share Data
Net income (in dollars per share)	$ 0.50	$ 0.46	$ 1.24	$ 1.11
Shares used to compute basic per common share amounts (in shares)	34,362,757	33,571,967	34,224,756	33,477,951
Diluted Per Common Share Data
Net income (in dollars per share)	$ 0.50	$ 0.45	$ 1.21	$ 1.08
Shares used to compute diluted per common share amounts (in shares)	35,002,351	34,347,215	34,817,680	34,215,105