Consolidated Statements Of Stockholders' Equity (USD $) In Thousands, except Share data	Total	Common Stock	Additional Paid-In Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]
Balance at Dec. 31, 2011	$ 1,458,976us-gaap_StockholdersEquity	$ 2,953	$ 16,856	$ 1,424,371	$ 14,796
Balance (in shares) at Dec. 31, 2011		295,258,000
Dividends paid in cash	(367,306)us-gaap_DividendsCash			(367,306)
Stock options exercised	29,644	13	29,631
Stock options exercised (in shares)		1,306,000
Stock-based compensation	4,800		4,800
Excess tax benefits from stock-based compensation	10,149		10,149
Net earnings	420,536us-gaap_NetIncomeLoss			420,536
Other comprehensive income (loss)	3,561				3,561
Balance at Dec. 31, 2012	1,560,360us-gaap_StockholdersEquity	2,966	61,436	1,477,601	18,357
Balance (in shares) at Dec. 31, 2012		296,564,000
Dividends paid in cash	(237,456)us-gaap_DividendsCash			(237,456)
Purchases of common stock	(9,080)	(2)	(9,078)
Purchases of common stock (in shares)		(200,000)
Stock options exercised	9,306	4	9,302
Stock options exercised (in shares)		389,000
Stock-based compensation	5,400		5,400
Excess tax benefits from stock-based compensation	2,787		2,787
Net earnings	448,636us-gaap_NetIncomeLoss			448,636
Other comprehensive income (loss)	(7,256)				(7,256)
Balance at Dec. 31, 2013	1,772,697us-gaap_StockholdersEquity	2,968	69,847	1,688,781	11,101
Balance (in shares) at Dec. 31, 2013	296,753,544us-gaap_CommonStockSharesOutstanding	296,753,000
Dividends paid in cash	(296,581)us-gaap_DividendsCash			(296,581)
Purchases of common stock	(52,942)	(12)	(52,930)
Purchases of common stock (in shares)		(1,200,000)
Stock options exercised	7,697	3	7,694
Stock options exercised (in shares)		315,000
Stock-based compensation	7,039		7,039
Excess tax benefits from stock-based compensation	2,094		2,094
Net earnings	494,150us-gaap_NetIncomeLoss			494,150
Other comprehensive income (loss)	(18,937)				(18,937)
Balance at Dec. 31, 2014	$ 1,915,217us-gaap_StockholdersEquity	$ 2,959	$ 33,744	$ 1,886,350	$ (7,836)
Balance (in shares) at Dec. 31, 2014	295,867,844us-gaap_CommonStockSharesOutstanding	295,868,000

This element represents the amount of recognized equity-based compensation during the period, that is, the amount recognized as expense in the income statement (or as asset if compensation is capitalized). Alternate captions include the words "stock-based compensation".

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Amount of increase in additional paid in capital (APIC) resulting from a tax benefit associated with share-based compensation plan other than an employee stock ownership plan (ESOP). Includes, but is not limited to, excess tax benefit.

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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Amount of paid and unpaid cash dividends declared for classes of stock, for example, but not limited to, common and preferred.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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Number of share options (or share units) exercised during the current period.

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Value of stock issued as a result of the exercise of stock options.

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Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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Equity impact of the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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