Face (par) amount of debt instrument at time of issuance.

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Contractual interest rate for funds borrowed, under the debt agreement.

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The cash outflow for the extinguishment of long-term borrowing, with the highest claim on the assets of the entity in case of bankruptcy or liquidation, before its maturity.

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Amount of gain (loss) recognized in settlement of litigation and insurance claims. Excludes claims within an insurance entity's normal claims settlement process.

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Amount of judgment or settlement awarded to (against) the entity in respect of litigation.

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The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer.

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Cash received for the settlement of litigation during the current period.

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The cash outflow for a long-term debt where the holder has highest claim on the entity's asset in case of bankruptcy or liquidation during the period.

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Asset Acquisitions, Dispositions and Other - Settlement, Tax Refund and Debt Issuance (Details) - USD ($) $ in Millions	1 Months Ended					3 Months Ended		9 Months Ended
	Jun. 30, 2016	May 31, 2016	Apr. 30, 2016	Feb. 29, 2016	Jan. 31, 2016	Jun. 30, 2016	Mar. 31, 2016	Sep. 30, 2016	Sep. 30, 2015
Debt Instruments [Abstract]
Net proceeds from issuance of long-term debt								$ 2,718	$ 1,478
Republic of Ecuador
Litigation Settlement
Proceeds from settlement						$ 330
Pre-tax gain on settlement							$ 681
Award amount					$ 1,000
Senior unsecured notes
Debt Instruments [Abstract]
Debt instrument issued			$ 2,750
Net proceeds from issuance of long-term debt			$ 2,720
2.60% senior unsecured notes due 2022
Debt Instruments [Abstract]
Debt instrument interest rate stated percentage			2.60%
Debt instrument issued			$ 400
3.40% senior unsecured notes due 2026
Debt Instruments [Abstract]
Debt instrument interest rate stated percentage			3.40%
Debt instrument issued			$ 1,150
4.40% senior unsecured notes due 2046
Debt Instruments [Abstract]
Debt instrument interest rate stated percentage			4.40%
Debt instrument issued			$ 1,200
2.50% senior unsecured notes
Debt Instruments [Abstract]
Debt instrument interest rate stated percentage				2.50%
Retired debt				$ 700
4.125% senior unsecured notes due 2016
Debt Instruments [Abstract]
Debt instrument interest rate stated percentage	4.125%					4.125%
Retired debt	$ 750
1.75% senior unsecured notes due 2017
Debt Instruments [Abstract]
Early repayment of debt through exercise of redemption option		$ 1,250
Debt instrument interest rate stated percentage		1.75%