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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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			2 Months Ended	3 Months Ended		6 Months Ended
	Apr. 30, 2016	Feb. 29, 2016	Jan. 31, 2016	Jun. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Jun. 30, 2016	Jun. 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%		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%	1.75%		1.75%