Condensed Consolidated Statements of Cash Flows (Unaudited) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2012 USD ($)	Sep. 30, 2011 USD ($)
Cash flows from operating activities:
Net income	$ 48,839	$ 58,131
Adjustments to reconcile net income to net cash provided by operations:
Depreciation and amortization	24,406	21,162
Stock-based compensation expense	5,027	3,396
Provision for deferred income taxes	(4,654)	16,363
Net provision for doubtful accounts	1,282	1,165
Loss on sale of assets	512	22
Change in assets and liabilities:
Decrease (increase) in receivables	11,964	(57,603)
Increase in inventories	(6,446)	(27,921)
Increase in other assets	(98)	(5,226)
Increase in accounts payable	2,905	28,893
Decrease in accrued liabilities and other	(3,085)	(3,655)
Net cash provided by operating activities	80,652	34,727
Cash flows from investing activities:
Capital expenditures	(34,858)	(28,136)
Business acquisition, net of cash acquired		(26,775)
Proceeds from sale of property, plant and equipment	823	434
Net cash used in investing activities	(34,035)	(54,477)
Cash flows from financing activities:
Borrowings on lines of credit	222,868	5,891
Payments on lines of credit	(213,221)	(5,754)
Proceeds from employee stock plans	1,007	1,768
Purchase of treasury stock	(35,698)	(599)
Post-closing payment for business acquisition	(11,892)	(2,055)
Other financing activities	(48)	(147)
Net cash used in financing activities	(36,984)	(896)
Effect of exchange rate changes on cash	577	538
Net increase (decrease) in cash and cash equivalents	10,210	(20,108)
Cash and cash equivalents at beginning of year	25,247	83,010
Cash and cash equivalents at end of period	35,457	62,902
Cash paid for:
Income taxes (net of refunds)	17,370	20,752
Interest	$ 4,665	$ 3,775