CONSOLIDATED STATEMENTS OF INCOME AND COMPREHENSIVE INCOME (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Net sales	$ 218,091	$ 200,439
Material costs	66,697	59,111
Personnel costs	81,153	78,267
Other operating expenses	40,219	36,100
Relocation expenses		376
Depreciation and amortization	8,285	7,292
Income from operations	21,737	19,293
Interest expense	7,777	8,379
Income before taxes	13,960	10,914
Provision for income taxes	5,324	4,162
Net income	8,636	6,752
Other comprehensive income	0
Comprehensive income	$ 8,636	$ 6,752
Basic Per Common Share Data
Net income (in dollars per share)	$ 0.25	$ 0.20
Shares used to compute basic per common share amounts (in shares)	34,036,539	33,360,840
Diluted Per Common Share Data
Net income (in dollars per share)	$ 0.25	$ 0.20
Shares used to compute diluted per common share amounts (in shares)	34,639,660	34,134,067