Fair Value Measurements (Fair Value Measurements At Reporting Date) (Details) - USD ($) $ in Millions	Sep. 30, 2015	Dec. 31, 2014
Assets:
Available-for-sale Securities, Fair Value Disclosure	$ 853	$ 1,000
Deferred receivables consideration	1,067	511
Fair Value, Measurements, Recurring [Member]
Assets:
Inventories carried at market	3,882	4,699
Cash Equivalents, at Carrying Value	28	491
Available-for-sale Securities, Fair Value Disclosure	849	940
Restricted Investments, at Fair Value	1,834	2,158
Deferred receivables consideration	1,067	511
Total Assets	8,575	9,696
Liabilities:
Inventory-related payables	543	652
Total Liabilities	1,402	1,578
Fair Value, Measurements, Recurring [Member] | Commodity Contracts [Member]
Assets:
Derivative Asset	782	690
Derivative Liability	545	776
Fair Value, Measurements, Recurring [Member] | Foreign Exchange Contracts [Member]
Assets:
Derivative Asset	103	186
Derivative Liability	314	150
Fair Value, Measurements, Recurring [Member] | Interest Rate Contracts [Member]
Assets:
Derivative Asset	30	21
Fair Value, Measurements, Recurring [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member]
Assets:
Inventories carried at market	0	0
Cash Equivalents, at Carrying Value	28	491
Available-for-sale Securities, Fair Value Disclosure	810	860
Restricted Investments, at Fair Value	1,834	2,158
Deferred receivables consideration	0	0
Total Assets	2,673	3,509
Liabilities:
Inventory-related payables	0	0
Total Liabilities	0	0
Fair Value, Measurements, Recurring [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Commodity Contracts [Member]
Assets:
Derivative Asset	0	0
Derivative Liability	0	0
Fair Value, Measurements, Recurring [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Foreign Exchange Contracts [Member]
Assets:
Derivative Asset	1	0
Derivative Liability	0	0
Fair Value, Measurements, Recurring [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Interest Rate Contracts [Member]
Assets:
Derivative Asset	0	0
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member]
Assets:
Inventories carried at market	2,952	3,208
Available-for-sale Securities, Fair Value Disclosure	39	80
Deferred receivables consideration	1,067	511
Total Assets	4,770	4,493
Liabilities:
Inventory-related payables	509	612
Total Liabilities	1,214	1,326
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Commodity Contracts [Member]
Assets:
Derivative Asset	580	487
Derivative Liability	391	564
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Foreign Exchange Contracts [Member]
Assets:
Derivative Asset	102	186
Derivative Liability	314	150
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Interest Rate Contracts [Member]
Assets:
Derivative Asset	30	21
Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member]
Assets:
Inventories carried at market	930	1,491
Available-for-sale Securities, Fair Value Disclosure	0	0
Deferred receivables consideration	0	0
Total Assets	1,132	1,694
Liabilities:
Inventory-related payables	34	40
Total Liabilities	188	252
Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Commodity Contracts [Member]
Assets:
Derivative Asset	202	203
Derivative Liability	154	212
Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Foreign Exchange Contracts [Member]
Assets:
Derivative Asset	0	0
Derivative Liability	0	0
Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Interest Rate Contracts [Member]
Assets:
Derivative Asset	$ 0	$ 0