Investments (Policy)	9 Months Ended
Jun. 30, 2011
Investments
Investments In ClearTrip	Our investment in ClearTrip's common stock and certain classes of preferred stock are accounted for under the equity method because our total ownership interest exceeds 20% and we have the ability to exert significant influence. Under the equity method, we record our investment at cost and adjust the carrying amount of the investment to recognize our proportionate share of ClearTrip's net income or loss in our income statement after the date of acquisition.
Investments In RideCharge	Because our preferred stock in RideCharge does not meet all the characteristics of in-substance common stock, we have accounted for our investment under the cost method with net accumulated earnings recorded only to the extent of distributed dividends. We have reported our investment in RideCharge in "Investments" on our balance sheet.

Investments (Policy)

9 Months Ended

Jun. 30, 2011

Our investment in ClearTrip's common stock and certain classes of preferred stock are accounted for under the equity method because our total ownership interest exceeds 20% and we have the ability to exert significant influence. Under the equity method, we record our investment at cost and adjust the carrying amount of the investment to recognize our proportionate share of ClearTrip's net income or loss in our income statement after the date of acquisition.

Investments In RideCharge

Because our preferred stock in RideCharge does not meet all the characteristics of in-substance common stock, we have accounted for our investment under the cost method with net accumulated earnings recorded only to the extent of distributed dividends. We have reported our investment in RideCharge in "Investments" on our balance sheet.

- Definition

Disclosure of accounting policy for the cost method of accounting for investments in common stock or other interests including unconsolidated subsidiaries, corporate joint ventures, noncontrolling interests in real estate ventures, limited partnerships, and limited liability companies. An entity also may describe how such investments are assessed for impairment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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Reference 7: http://www.xbrl.org/2003/role/presentationRef
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+ Details

- Definition

Disclosure of accounting policy for the equity method of accounting for investments in common stock or other interests including unconsolidated subsidiaries, corporate joint ventures, noncontrolling interests in real estate ventures, limited partnerships, and limited liability companies. The accounting policy may include information such as: (1) initially recording an investment in the stock of an investee at cost; (2) adjusting the carrying amount of the investment to recognize the investor's share of the earnings or losses of the investee after the date of acquisition; and (3) adjustments to reflect the investor's share of changes in the investee's capital (dividends). This disclosure may also include a detailed description of the policy for determining the amount of equity method losses recognized after an investment has been reduced to zero as a result of previous losses, reasons for not using the equity method when the investor company owns 20 percent or more of the voting stock of the investee's company (including identification of the significant investee), reasons for using the equity method when the ownership percentage is less than 20 percent, and discussion of recognition of equity method losses when an investor's total investment in an investee includes, in addition to an investment in common stock, other investments such as preferred stock and loans to the investee. An entity also may describe how such investments are assessed for impairment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Emerging Issues Task Force (EITF)
-Number 99-10
-Paragraph 6, 7
-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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-Name Accounting Principles Board Opinion (APB)
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-Name Accounting Standards Codification
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-Name Regulation S-X (SX)
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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.

+ Details