Condensed Consolidated Statements of Operations (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Condensed Consolidated Statements of Operations
Net sales	$ 195,596	$ 181,703	$ 350,130	$ 340,437
Cost of sales	106,176	98,557	195,736	187,886
Gross profit	89,420	83,146	154,394	152,551
Operating expenses:
Research and development and other engineering	9,484	9,043	17,792	18,240
Selling	21,652	19,881	43,024	40,314
General and administrative	28,595	27,087	54,884	53,331
Loss (gain) on sale of assets	11	(13)	3	10
Total operating expenses	59,742	55,998	115,703	111,895
Income from operations	29,678	27,148	38,691	40,656
Interest income, net	1	58	40	123
Income before taxes	29,679	27,206	38,731	40,779
Provision for income taxes	11,177	11,347	15,434	17,719
Net income	$ 18,502	$ 15,859	$ 23,297	$ 23,060
Earnings per common share:
Basic (in dollars per share)	$ 0.38	$ 0.33	$ 0.48	$ 0.48
Diluted (in dollars per share)	$ 0.38	$ 0.33	$ 0.48	$ 0.48
Number of shares outstanding
Basic (in shares)	48,529	48,340	48,532	48,307
Diluted (in shares)	48,628	48,419	48,627	48,378
Cash dividends declared per common share (in dollars per share)	$ 0.125	$ 0.125	$ 0.125	$ 0.25

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