Condensed Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2012
Current assets
Cash and cash equivalents	$ 215,764	$ 175,553	$ 187,471
Trade accounts receivable, net	118,895	82,812	108,425
Inventories	187,255	204,124	172,021
Deferred income taxes	12,330	11,473	12,302
Assets held for sale		593
Other current assets	12,519	23,499	11,890
Total current assets	546,763	498,054	492,109
Property, plant and equipment, net	209,641	213,452	211,132
Goodwill	130,270	121,981	128,812
Intangible assets, net	36,955	50,598	40,075
Other noncurrent assets	10,547	6,237	6,868
Total assets	934,176	890,322	878,996
Current liabilities
Line of credit and notes payable	956	178	193
Trade accounts payable	33,450	37,117	24,225
Accrued liabilities	47,268	44,923	44,807
Income taxes payable			1,007
Accrued profit sharing trust contributions	4,573	5,191	4,003
Accrued cash profit sharing and commissions	12,471	3,414	8,911
Accrued workers' compensation	5,195	4,692	4,880
Total current liabilities	103,913	95,515	88,026
Long-term liabilities	7,803	5,239	4,810
Total liabilities	111,716	100,754	92,836
Commitments and contingencies (Note 7)
Stockholders' equity
Common stock, at par value	487	483	482
Additional paid-in capital	194,721	184,677	178,962
Retained earnings	623,529	592,309	598,533
Treasury stock	(9,825)
Accumulated other comprehensive income	13,548	12,099	8,183
Total stockholders' equity	822,460	789,568	786,160
Total liabilities and stockholders' equity	$ 934,176	$ 890,322	$ 878,996