Condensed Consolidated Statements Of Cash Flows (USD $) In Thousands	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010
Operating activities
Net income	$ 43,880	$ 53,695
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Depreciation and amortization	10,606	10,080
Stock-based compensation expense	2,394	2,395
Gain on sale of equipment	(364)	(122)
Deferred income taxes	270	(4,728)
Changes in operating assets and liabilities:
Trade receivables, net	(31,522)	(10,653)
Inventories, net	(17,250)	4,317
Prepaids and other assets	1,059	5,367
Excess tax benefits of stock option exercises	(249)	(1,110)
Trade accounts payable and accrued expenses	26,618	(15,501)
Net cash provided by operating activities	35,442	43,740
Investing activities
Purchase of property, plant and equipment	(32,839)	(21,980)
Proceeds from sale of equipment	2,023	1,078
Net cash used in investing activities	(30,816)	(20,902)
Financing activities
Principal payments on debt	(247)	(337)
Proceeds from exercise of stock options	386	4,226
Excess tax benefits of stock option exercises	249	1,110
Net cash provided by financing activities	388	4,999
Effect of exchange rate changes on cash activities	(746)	274
Increase in cash and cash equivalents	4,268	28,111
Cash and cash equivalents at beginning of period	245,850	197,792
Cash and cash equivalents at end of period	$ 250,118	$ 225,903

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Includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Entity may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Compensating balance arrangements that do not legally restrict the withdrawal or usage of cash amounts may be reported as Cash and Cash Equivalents, while legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or company statements of intention with regard to particular deposits should not be reported as cash and cash equivalents.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 7, 26

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 8, 9

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 7
-Footnote 1

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 1
-Article 5