Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Cash flows from operating activities
Net income	$ 266,447	$ 187,000	$ 133,982
Adjustments to reconcile net income to net cash provided by operating activities:
Loss (gain) on sale of assets and other	2,116	(318)	(6,023)
Depreciation and amortization	42,477	38,767	38,402
Noncash lease expense	9,562	6,984	7,136
Deferred income taxes	(915)	3,179	2,557
Noncash compensation related to stock plans	17,715	13,507	10,434
Provision for (benefit from ) doubtful accounts	393	(98)	977
Changes in operating assets and liabilities, net of effects of acquisitions and dispositions:
Trade accounts receivable	(67,993)	(22,107)	6,096
Inventories	(164,202)	(27,219)	23,655
Other current assets	(1,951)	(845)	(3,808)
Trade accounts payable	10,235	11,360	(845)
Accrued liabilities and other current liabilities	50,548	7,754	(145)
Other noncurrent assets and liabilities	(13,137)	(10,392)	(6,756)
Net cash provided by operating activities	151,295	207,572	205,662
Cash flows from investing activities
Capital expenditures	(43,738)	(32,579)	(32,699)
Acquisitions, net of cash acquired	(218)	(2,797)	(2,650)
Purchases of intangible assets	(5,856)	(5,330)	(4,827)
Purchases of Equity investments	(9,829)	0	0
Proceeds from sale of property and equipment	836	853	12,155
Net cash used in investing activities	(58,805)	(39,853)	(28,021)
Cash flows from financing activities
Proceeds from lines of credit	16,752	169,164	16,647
Repayments of line of credit and capital leases	(16,408)	(170,680)	(17,883)
Debt issuance costs	(819)	(712)	0
Repurchase of common stock	(24,125)	(76,189)	(60,816)
Dividends paid	(41,619)	(40,400)	(40,197)
Cash paid on behalf of employees for shares withheld	(5,397)	(7,960)	(5,905)
Net Cash Provided by (Used in) Financing Activities, Total	(71,616)	(126,777)	(108,154)
Effect of exchange rate changes on cash	5,642	3,487	543
Net increase in cash and cash equivalents	26,516	44,429	70,030
Cash and cash equivalents at beginning of year	274,639	230,210	160,180
Cash and cash equivalents at end of year	301,155	274,639	230,210
Cash paid during the year for
Interest	1,597	1,598	143
Income taxes	83,662	63,035	37,730
Noncash activity during the year for
Noncash capital expenditures	99	3,719	557
Contingent consideration for acquisition	0	547	0
Issuance of Company’s common stock for compensation	691	341	292
Dividends declared but not paid	$ 10,806	$ 9,999	$ 10,170