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Earnings from discontinued operations allocated (not distributed) to participating securities under the two-class method to the extent that participating securities may share in earnings as if all of the earnings for the period had been distributed.

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Earnings allocated (not distributed) to participating securities under the two-class method to the extent that participating securities may share in earnings as if all of the earnings for the period had been distributed.

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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) in the future that were not included in the computation of diluted EPS because to do so would increase EPS amounts or decrease loss per share amounts for the period presented.

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After tax income (loss) from operations of a business component (exclusive of any gain or loss on disposal, or provision therefore) during the reporting period, until its disposal.

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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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This element represents the income or loss from continuing operations attributable to the economic entity which may also be defined as revenue less expenses and taxes from ongoing operations before extraordinary items, cumulative effects of changes in accounting principles, and noncontrolling interest.

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The amount of income (loss) from continuing operations per each share of common stock outstanding during the reporting period.

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The amount of income (loss) from continuing operations available to each share of common stock outstanding during the reporting period and each share that would have been outstanding assuming the issuance of common shares for all dilutive potential common shares outstanding during the reporting period.

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The amount of income (loss) from disposition of discontinued operations, net of related tax effect, per each share of common stock outstanding during the reporting period.

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The amount of income (loss) from discontinued operations, net of related tax effect, per each diluted share of common stock outstanding during the reporting period.

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This element represents nonvested share-based payment awards that contain non-forfeitable rights to dividends or dividend equivalents (whether paid or unpaid). Basic and dilutive earnings per share are generally disclosed for such shares using the two-class method.

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Net income after adjustments for dividends on preferred stock (declared in the period) and/or cumulative preferred stock (accumulated for the period).

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Net Income (Loss) Available to Common Stockholders plus adjustments resulting from the assumption that dilutive convertible securities were converted, options or warrants were exercised, or that other shares were issued upon the satisfaction of certain conditions.

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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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Earnings Per Share (Details) (USD $) In Thousands, except Share data	3 Months Ended								12 Months Ended
	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010	Sep. 30, 2010	Jun. 30, 2010	Mar. 31, 2010	Dec. 31, 2009	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2009
Basic Earnings per Share from Continuing Operations
Income (loss) from continuing operations	$ 1,098	$ (1,474)	$ 128,160	$ 71,100	$ 244	$ (4,229)	$ 111,283	$ 90,975	$ 198,884	$ 198,273	$ 183,299
Less: Income (loss) from continuing operations allocated to participating securities									2,077	2,029	1,712
Income (loss) from continuing operations available to common shareholders									196,807	196,244	181,587
Income Loss From Continuing Operations Per Basic Share	$ 0.01	$ (0.02)	$ 1.41	$ 0.78	$ 0	$ (0.04)	$ 1.19	$ 0.97	$ 2.18	$ 2.14	$ 1.99
Basic Earnings per Share from Discontinued Operations
Income (loss) from discontinued operations	863	908	4,049	2,897	1,293	1,075	2,843	2,355	8,717	7,566	7,679
Less: Income (loss) from discontinued operations allocated to participating securities									91	77	72
Income (loss) from discontinued operations available to common shareholders									8,626	7,489	7,607
Income (loss) from discontinued operations per share - Basic	$ 0.01	$ 0.01	$ 0.04	$ 0.03	$ 0.02	$ 0.01	$ 0.03	$ 0.03	$ 0.10	$ 0.08	$ 0.09
Basic net income (loss) per share	$ 0.02	$ (0.01)	$ 1.45	$ 0.81	$ 0.02	$ (0.03)	$ 1.22	$ 1.00	$ 2.28	$ 2.22	$ 2.08
Basic									90,201,000	91,852,000	91,117,000
Diluted Earnings per Share from Continuing Operations
Effect of dilutive stock options and other shares									4	5	4
Income (loss) from continuing operations available to common shareholders									196,811	196,249	181,591
Additional dilutive stock options and other shares									451,000	570,000	503,000
Diluted									90,652,000	92,422,000	91,620,000
Income Loss From Continuing Operations Per Diluted Share	$ 0.01	$ (0.02)	$ 1.41	$ 0.78	$ 0	$ (0.04)	$ 1.19	$ 0.97	$ 2.17	$ 2.12	$ 1.98
Diluted Earnings per Share from Discontinued Operations
Effect of dilutive stock options and other shares									0	0	0
Income (loss) from discontinued operations available to common shareholders									$ 8,626	$ 7,489	$ 7,607
Additional dilutive stock options and other shares									451,000	570,000	503,000
Diluted weighted average shares outstanding									90,652,000	92,422,000	91,620,000
Income (loss) from discontinued operations per share - Diluted	$ 0.01	$ 0.01	$ 0.04	$ 0.03	$ 0.02	$ 0.01	$ 0.03	$ 0.03	$ 0.10	$ 0.08	$ 0.09
Diluted net income (loss) per share	$ 0.02	$ (0.01)	$ 1.45	$ 0.81	$ 0.02	$ (0.03)	$ 1.22	$ 1.00	$ 2.27	$ 2.20	$ 2.07
Earnings Per Share Diluted Other Disclosures Abstract
Anti-dilutive stock options excluded from computation of diluted earnings per share											70,000