Condensed Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013
Cash flows from operating activities
Net income	$ 32,538	$ 23,297
Adjustments to reconcile net income to net cash used in operating activities:
(Gain) loss on sale of assets	(319)	3
Depreciation and amortization	14,785	14,777
Impairment loss on assets	0	1,025
Deferred income taxes	43	1,281
Noncash compensation related to stock plans	6,201	6,001
Excess tax benefit of options exercised and restricted stock units vested	(14)	(11)
Provision for doubtful accounts	141	9
Changes in operating assets and liabilities, net of acquisitions:
Trade accounts receivable	(47,732)	(45,345)
Inventories	(21,597)	7,168
Trade accounts payable	(7,138)	(7,021)
Income taxes payable	8,170	11,859
Accrued profit sharing trust contributions	(2,367)	(1,944)
Accrued cash profit sharing and commissions	6,157	8,624
Other current assets	(2,294)	185
Accrued liabilities	1,800	(1,502)
Long-term liabilities	2,608	(477)
Accrued workers’ compensation	(162)	403
Other noncurrent assets	(318)	578
Net cash (used in) provided by operating activities	(9,498)	18,910
Cash flows from investing activities
Capital expenditures	(9,298)	(8,095)
Asset acquisitions, net of cash acquired	0	(5,300)
Proceeds from sale of property and equipment	565	110
Loan made to customer	281	0
Loan repayment by customer	4	0
Loan repayment by related party	0	625
Net cash used in investing activities	(9,010)	(12,660)
Cash flows from financing activities
Deferred and contingent consideration paid for asset acquisition	1,293	0
Repurchase of common stock	0	(9,825)
Debt and line of credit borrowings	0	1,129
Repayment of debt and line of credit borrowings	(41)	(86)
Issuance of common stock	2,626	776
Excess tax benefit of options exercised and restricted stock units vested	14	11
Dividends paid	(12,207)	(6,053)
Net cash used in financing activities	(10,901)	(14,048)
Effect of exchange rate changes on cash and cash equivalents	(603)	(2,480)
Net decrease in cash and cash equivalents	(30,012)	(10,278)
Cash and cash equivalents at beginning of period	251,208	175,553
Cash and cash equivalents at end of period	221,196	165,275
Noncash activity during the period
Noncash capital expenditures	672	63
Dividends declared but not paid	6,853	6,068
Issuance of Company’s common stock for compensation	$ 402	$ 318