Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Cash flows from operating activities
Net income	$ 50,900	$ 28,586	$ 12,217
Adjustments to reconcile net income to net cash provided by operating activities:
Loss (gain) on sale of assets	191	(4,763)	797
Loss on sale of discontinued operations		657
Depreciation and amortization	20,751	22,861	29,387
Impairment loss on discontinued operations		16,916
Impairment of long-lived assets	1,094	419
Impairment of goodwill	1,282	6,292
Deferred income taxes	(2,163)	6,956	(2,198)
Noncash compensation related to stock plans	6,837	3,712	2,200
Loss (gain) in equity method investment	(4,389)	535	194
Excess tax benefit of options exercised		(10)	(359)
Write down of excess and obsolete inventory	750	5,046	900
Provision for (recovery of) doubtful accounts	67	(81)	666
Accrued interest earned from related party	(58)		(78)
Changes in operating assets and liabilities, net of effects of acquisitions and dispositions:
Trade accounts receivable	(6,982)	(3,715)	2,574
Inventories	(26,946)	(12,143)	92,589
Other current assets	(190)	1,026	(4,123)
Other noncurrent assets	1,376	41	(1,146)
Trade accounts payable	(10,126)	4,678	4,770
Accrued liabilities	2,899	2,223	(6,754)
Accrued profit sharing trust contributions	(1,102)	(1,442)	(2,614)
Accrued cash profit sharing and commissions	673	432	92
Other long-term liabilities	(1,112)	(1,257)	1,520
Accrued workers' compensation	790	332	66
Income taxes payable	545	(104)	(4,540)
Net cash provided by operating activities	35,087	77,197	126,160
Cash flows from investing activities
Capital expenditures	(26,063)	(28,341)	(15,226)
Asset acquisitions, net of cash acquired	(51,853)	(5,214)	(24,261)
Loans made to related parties		(1,798)	(1,204)
Loan repayments by related parties	552	50
Proceeds from sale of discontinued operations		28,346
Proceeds from sale of capital assets	3,081	14,841	1,218
Net cash provided by (used in) investing activities	(74,283)	7,884	(39,473)
Cash flows from financing activities
Line of credit borrowings			1,514
Repayment of line of credit borrowings			(1,540)
Repurchase of common stock	(53,208)
Issuance of Company's common stock	214	17,948	7,627
Excess tax benefit of options exercised		10	359
Dividends paid	(23,329)	(19,764)	(19,633)
Net cash used in financing activities	(76,323)	(1,806)	(11,673)
Effect of exchange rate changes on cash	(5,713)	1,393	4,617
Net increase (decrease) in cash and cash equivalents	(121,232)	84,668	79,631
Cash and cash equivalents at beginning of year	335,049	250,381	170,750
Cash and cash equivalents at end of year	213,817	335,049	250,381
Cash paid during the year for
Interest	279	232	287
Income taxes	30,789	20,508	23,322
Noncash activity during the year for
Capital expenditures	402	3,276	278
Asset acquisition	363
Common stock issued for compensation	204	301	300
Dividends declared but not paid	6,020	5,013	4,939
Equity method investment acquisition (Note 6)	$ 708		$ 728