15. Derivative Financial Instruments (Details) (USD $) In Millions, unless otherwise specified	Sep. 30, 2013
Cash Flow Hedge Derivative Notional Amount	$ 40,000
Cash Flow Hedge Derivative Assets Fair Value	0
Cash Flow Hedge Derivative Liability Fair Value	117
Cash Flow Hedge Derivative Net ineffective hedge gain losses	0
Long-term Debt [Member]
Cash Flow Hedge Derivative Notional Amount	40,000
Cash Flow Hedge Derivative Assets Fair Value	0
Cash Flow Hedge Derivative Liability Fair Value	117
Cash Flow Hedge Derivative Net ineffective hedge gain losses	$ 0

Cash Flow Hedge Derivative Liability Notional Amount.

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- Definition

Cash Flow Hedge Derivative Net Ineffective Hedge Gain Losses Accumulated.

+ References

No definition available.

+ Details

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- Definition

Fair value of all asset derivatives designated as cash flow hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4B

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624163-113959

+ Details

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- Definition

Fair value of all liability derivatives designated as cash flow hedging instruments.

+ References

+ Details

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