Condensed Consolidated Statements Of Income (USD $) In Thousands, except Per Share data	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Condensed Consolidated Statements Of Income
Net sales	$ 665,481	$ 615,459	$ 1,294,981	$ 1,166,191
Cost of sales	(528,580)	(483,794)	(1,024,939)	(947,727)
Gross profit	136,901	131,665	270,042	218,464
Selling and administrative expenses	(48,192)	(44,653)	(96,144)	(88,930)
Corporate overhead	(16,352)	(15,386)	(31,905)	(28,016)
Alternative fuel mixture tax credits				9,235
Other expense, net	(4,498)	(3,880)	(8,231)	(9,391)
Income from operations	67,859	67,746	133,762	101,362
Interest expense, net	(6,321)	(8,093)	(13,224)	(16,816)
Income before taxes	61,538	59,653	120,538	84,546
Provision for income taxes	(22,170)	(21,623)	(43,753)	(27,322)
Net income	$ 39,368	$ 38,030	$ 76,785	$ 57,224
Weighted average common shares outstanding:
Basic	100,094	102,035	100,416	101,982
Diluted	101,128	102,886	101,518	102,885
Net income per common share:
Basic	$ 0.39	$ 0.37	$ 0.76	$ 0.56
Diluted	$ 0.39	$ 0.37	$ 0.76	$ 0.56
Dividends declared per common share	$ 0.20	$ 0.15	$ 0.40	$ 0.30

The total amount of tax credits earned for the production and use of alternative fuels in an entity's trade or business.

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The aggregate total of general and administrative expenses for corporate departments that are not associated with the manufacture, sale or creation of a product or product line.

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Revenue less expenses and interest from the entity's ongoing operations and before (1) income tax expense (benefit), (2) income (loss) from discontinued operations, (3) extraordinary items, (4) impact of changes in accounting principles, (5) minority interest, and (6) various other reconciling adjustments.

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The cost of borrowed funds accounted for as interest that was charged against earnings during the period, net of interest earned on invested cash.

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The total amount of other operating income and expense items, not previously categorized, that are associated with the entity's normal revenue producing operation.

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Aggregate dividends declared during the period for each share of common stock outstanding.

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Total costs related to goods produced and sold during the reporting period.

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The amount of net income or loss for the period per each share of common stock outstanding during the reporting period.

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The amount of net income or loss for the period per each share of common stock and dilutive common stock equivalents outstanding during the reporting period.

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Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity.

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The sum of the current income tax expense (benefit) and the deferred income tax expense (benefit) pertaining to continuing operations.

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The portion of consolidated profit or loss for the period, net of income taxes, which is attributable to the parent. If the entity does not present consolidated financial statements, the amount of profit or loss for the period, net of income taxes.

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The net result for the period of deducting operating expenses from operating revenues.

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Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

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The aggregate total costs related to selling a firm's product and services, as well as all other general and administrative expenses. Direct selling expenses (for example, credit, warranty, and advertising) are expenses that can be directly linked to the sale of specific products. Indirect selling expenses are expenses that cannot be directly linked to the sale of specific products, for example telephone expenses, Internet, and postal charges. General and administrative expenses include salaries of non-sales personnel, rent, utilities, communication, etc.

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The average number of shares issued and outstanding that are used in calculating diluted EPS, determined based on the timing of issuance of shares in the period.

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Number of [basic] shares, after adjustment for contingently issuable shares and other shares not deemed outstanding, determined by relating the portion of time within a reporting period that common shares have been outstanding to the total time in that period.

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