Pretax compensation expense recognized related to the Long Term Incentive Program in the period.

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The associated total compensation for each of the three year performance periods related to the 2008 LTIP.

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The estimated total compensation for each of the three year performance periods related to the 2009 LTIP.

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The estimated total compensation for each of the three year performance periods related to the 2010 LTIP.

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The estimated total compensation for each of the three year performance periods related to the 2011 LTIP.

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- Definition

The aggregate amount of noncash, equity-based employee remuneration capitalized in fixed costs.

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Related tax expense associated with the aggregate amount of noncash, equity-based employee remuneration recognized as expense in the Consoldiated Statements of Operations. This may include the value of stock options, amortization of restricted stock, and adjustment for officers compensation.

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Lower exercise price range for options exercised during the period.

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Lower exercise price range of forfeited stock options.

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Shares of stock options exercised during the period.

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Forfeited Stock Option Shares

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Upper exercise price range for options exercised during the period.

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Upper exercise price range of forfeited stock options.

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The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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Equity-based compensation cost during the period with respect to the award, which will be recognized in income (as well as the total recognized tax benefit) or capitalized as part of the cost of an asset.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

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The number of shares reserved for issuance pertaining to the outstanding stock options as of the balance sheet date for all option plans in the customized range of exercise prices.

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-Publisher FASB

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The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

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Share Based Compensation (Details) (USD $) Share data in Thousands, except Per Share data	3 Months Ended		9 Months Ended			12 Months Ended	9 Months Ended	12 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011 Number Of Options [Member]	Dec. 31, 2010 Number Of Options [Member]	Sep. 30, 2011 Weighted Average Exercise Price [Member]	Dec. 31, 2010 Weighted Average Exercise Price [Member]	Dec. 31, 2009 Weighted Average Exercise Price [Member]
Valuation And Expense Information [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost	$ 5,344,000	$ 4,778,000	$ 15,475,000	$ 15,273,000
Amounts capitalized in fixed costs	1,898,000	1,793,000	5,583,000	6,151,000
Share-based Compensation	3,446,000	2,985,000	9,892,000	9,122,000
Amount of related income tax benefit recognized in income	1,237,000	1,060,000	3,551,000	3,238,000
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Number of Outstanding Options					2,230	3,504
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Lower Range Limit							$ 16.97	$ 3.91	$ 1.49
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Upper Range Limit							$ 98.87	$ 98.87	$ 98.87
Forfeited					(20)	(68)
Exercise Price, Lower Range Limit Forfeited							$ 51.60	$ 51.60
Exercise Price, Upper Range Limit Forfeited							$ 75.18	$ 76.01
Exercised					(661)	(1,206)
Exercise Price, Lower Range Limit Exercised							$ 3.91	$ 1.49
Exercise Price, Upper Range Limit Exercised							$ 33.57	$ 45.95
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Number of Outstanding Options					1,549	2,230
Long Term Incentive Program Period			7,500,000	5,900,000
Long Term Incentive Program Total 2009 Program			23,800,000
Long Term Incentive Program Total 2010 Program			11,500,000
Long Term Incentive Program Total 2008 Program			4,300,000
Long Term Incentive Program Total 2011 Program			$ 11,200,000