CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Operating activities
Net income	$ 30,291	$ 30,164
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	10,604	8,180
Deferred income taxes	2,501	1,272
Excess tax benefits from stock based compensation	(1,257)	(1,228)
Loss on disposal or impairment of assets	5	1,679
Foreign currency transaction loss, net	435	188
Stock compensation expense	1,682	1,359
Changes in operating assets and liabilities:
Trade accounts and other receivables	311	(17,907)
Inventories	(3,781)	118
Prepaid expenses and other current assets	150	(722)
Long-term prepaid expenses	766	433
Accounts payable	(10,255)	(377)
Accrued expenses	(14,881)	(4,108)
Accrued income taxes, net	12,698	13,880
Net cash provided by operating activities	29,269	32,931
Investing activities
Capital expenditures	(26,978)	(21,568)
Net cash used in investing activities	(26,978)	(21,568)
Financing activities
Proceeds from bank borrowings	10,000
Repayments on bank borrowings	(10,000)
Net proceeds from stock based compensation		76
Dividends paid	(5,555)	(4,632)
Purchase of common stock	(7,655)	(776)
Excess tax benefits from stock based compensation	1,257	1,228
Net cash used in financing activities	(11,953)	(4,104)
Effect of exchange rate changes on cash	425	444
Net (decrease) increase in cash and cash equivalents	(9,237)	7,703
Cash and cash equivalents at beginning of period	41,270	46,656
Cash and cash equivalents at end of period	32,033	54,359
Supplemental cash flow information
Interest paid	7
Income taxes paid	$ 517	$ 553