Fair Value (Recurring Measurements) (Details) (USD $) In Millions, unless otherwise specified	Sep. 30, 2014		Dec. 31, 2013
Debt securities:
Unsecured debentures	$ 484	[1]	$ 435	[1]
Certificates of deposit	119	[1]	151	[1]
Government debt securities	56	[1]	25	[1]
Subtotal	659	[1]	611	[1]
Equity securities:
Mutual funds	38	[1]	44	[1]
Subtotal	38	[1]	44	[1]
Total available-for-sale	697	[1]	655	[1]
Equity securities:
Mutual funds	15		13
Total trading	15		13
DERIVATIVES:
Total derivatives	192		240
TOTAL ASSETS	904		908
DERIVATIVES:
Total derivatives	491		371
TOTAL LIABILITIES	491		371
Interest rate derivatives [Member]
DERIVATIVES:
Total derivatives	20		98
DERIVATIVES:
Total derivatives	379		322
Cross currency derivatives [Member]
DERIVATIVES:
Total derivatives	0		5
DERIVATIVES:
Total derivatives	25		11
Foreign currency derivatives [Member]
DERIVATIVES:
Total derivatives	131		113
DERIVATIVES:
Total derivatives	53		21
Commodity derivatives [Member]
DERIVATIVES:
Total derivatives	41		24
DERIVATIVES:
Total derivatives	34		17
Level 1 [Member]
Debt securities:
Unsecured debentures	0	[1]	0	[1]
Certificates of deposit	0	[1]	0	[1]
Government debt securities	0	[1]	0	[1]
Subtotal	0	[1]	0	[1]
Equity securities:
Mutual funds	0	[1]	0	[1]
Subtotal	0	[1]	0	[1]
Total available-for-sale	0	[1]	0	[1]
Equity securities:
Mutual funds	15		13
Total trading	15		13
DERIVATIVES:
Total derivatives	0		0
TOTAL ASSETS	15		13
DERIVATIVES:
Total derivatives	0		0
TOTAL LIABILITIES	0		0
Level 1 [Member] | Interest rate derivatives [Member]
DERIVATIVES:
Total derivatives	0		0
DERIVATIVES:
Total derivatives	0		0
Level 1 [Member] | Cross currency derivatives [Member]
DERIVATIVES:
Total derivatives	0		0
DERIVATIVES:
Total derivatives	0		0
Level 1 [Member] | Foreign currency derivatives [Member]
DERIVATIVES:
Total derivatives	0		0
DERIVATIVES:
Total derivatives	0		0
Level 1 [Member] | Commodity derivatives [Member]
DERIVATIVES:
Total derivatives	0		0
DERIVATIVES:
Total derivatives	0		0
Level 2 [Member]
Debt securities:
Unsecured debentures	484	[1]	435	[1]
Certificates of deposit	119	[1]	151	[1]
Government debt securities	56	[1]	25	[1]
Subtotal	659	[1]	611	[1]
Equity securities:
Mutual funds	38	[1]	44	[1]
Subtotal	38	[1]	44	[1]
Total available-for-sale	697	[1]	655	[1]
Equity securities:
Mutual funds	0		0
Total trading	0		0
DERIVATIVES:
Total derivatives	77		136
TOTAL ASSETS	774		791
DERIVATIVES:
Total derivatives	303		263
TOTAL LIABILITIES	303		263
Level 2 [Member] | Interest rate derivatives [Member]
DERIVATIVES:
Total derivatives	20		98
DERIVATIVES:
Total derivatives	199		221
Level 2 [Member] | Cross currency derivatives [Member]
DERIVATIVES:
Total derivatives	0		5
DERIVATIVES:
Total derivatives	25		11
Level 2 [Member] | Foreign currency derivatives [Member]
DERIVATIVES:
Total derivatives	29		15
DERIVATIVES:
Total derivatives	46		16
Level 2 [Member] | Commodity derivatives [Member]
DERIVATIVES:
Total derivatives	28		18
DERIVATIVES:
Total derivatives	33		15
Level 3 [Member]
Debt securities:
Unsecured debentures	0	[1]	0	[1]
Certificates of deposit	0	[1]	0	[1]
Government debt securities	0	[1]	0	[1]
Subtotal	0	[1]	0	[1]
Equity securities:
Mutual funds	0	[1]	0	[1]
Subtotal	0	[1]	0	[1]
Total available-for-sale	0	[1]	0	[1]
Equity securities:
Mutual funds	0		0
Total trading	0		0
DERIVATIVES:
Total derivatives	115		104
TOTAL ASSETS	115		104
DERIVATIVES:
Total derivatives	188		108
TOTAL LIABILITIES	188		108
Level 3 [Member] | Interest rate derivatives [Member]
DERIVATIVES:
Total derivatives	0		0
DERIVATIVES:
Total derivatives	180		101
Level 3 [Member] | Cross currency derivatives [Member]
DERIVATIVES:
Total derivatives	0		0
DERIVATIVES:
Total derivatives	0		0
Level 3 [Member] | Foreign currency derivatives [Member]
DERIVATIVES:
Total derivatives	102		98
DERIVATIVES:
Total derivatives	7		5
Level 3 [Member] | Commodity derivatives [Member]
DERIVATIVES:
Total derivatives	13		6
DERIVATIVES:
Total derivatives	$ 1		$ 2

[1] Amortized cost approximated fair value at September 30, 2014 and December 31, 2013.