Employee Benefits Schedule of Fair Value of U.S Plan Assets (Details) (U.S. Pension Plan [Member], USD $) In Millions, unless otherwise specified	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011
Defined Benefit Plan Disclosure [Line Items]
Total	$ 1,855		$ 1,631		$ 1,325
Fair Value [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	1,855		1,631
Fair Value [Member] | Cash and cash equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	53	[1]	22	[1]
Fair Value [Member] | Large cap domestic
Defined Benefit Plan Disclosure [Line Items]
Total	303	[2]	233	[2]
Fair Value [Member] | Small cap domestic [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	66	[2]	44	[2]
Fair Value [Member] | Large cap international [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	212	[2]	188	[2]
Fair Value [Member] | Equity derivatives [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	361	[2]	226	[2]
Fair Value [Member] | Corporate bonds [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	395	[3]	421	[3]
Fair Value [Member] | Government and agency bonds [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	96	[3]	97	[3]
Fair Value [Member] | Asset-backed securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	25	[3]	18	[3]
Fair Value [Member] | Fixed income derivatives [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	13	[3]	52	[3]
Fair Value [Member] | Alternative investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	266	[4]	262	[4]
Fair Value [Member] | Commodity derivatives [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	14	[5]	17	[5]
Fair Value [Member] | Real estate and REITS [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	51	[6]	51	[6]
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	624		434
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Cash and cash equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	53	[1]	22	[1]
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Large cap domestic
Defined Benefit Plan Disclosure [Line Items]
Total	303	[2]	233	[2]
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Small cap domestic [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	5	[2]	0	[2]
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Large cap international [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	66	[2]	59	[2]
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Equity derivatives [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	146	[2]	69	[2]
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Corporate bonds [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	0	[3]	0	[3]
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Government and agency bonds [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	0	[3]	0	[3]
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Asset-backed securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	0	[3]	0	[3]
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Fixed income derivatives [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	0	[3]	0	[3]
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Alternative investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	0	[4]	0	[4]
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Commodity derivatives [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	0	[5]	0	[5]
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Real estate and REITS [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	51	[6]	51	[6]
Significant Other Observable Inputs (Level 2) [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	965		935
Significant Other Observable Inputs (Level 2) [Member] | Cash and cash equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	0	[1]	0	[1]
Significant Other Observable Inputs (Level 2) [Member] | Large cap domestic
Defined Benefit Plan Disclosure [Line Items]
Total	0	[2]	0	[2]
Significant Other Observable Inputs (Level 2) [Member] | Small cap domestic [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	61	[2]	44	[2]
Significant Other Observable Inputs (Level 2) [Member] | Large cap international [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	146	[2]	129	[2]
Significant Other Observable Inputs (Level 2) [Member] | Equity derivatives [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	215	[2]	157	[2]
Significant Other Observable Inputs (Level 2) [Member] | Corporate bonds [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	395	[3]	421	[3]
Significant Other Observable Inputs (Level 2) [Member] | Government and agency bonds [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	96	[3]	97	[3]
Significant Other Observable Inputs (Level 2) [Member] | Asset-backed securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	25	[3]	18	[3]
Significant Other Observable Inputs (Level 2) [Member] | Fixed income derivatives [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	13	[3]	52	[3]
Significant Other Observable Inputs (Level 2) [Member] | Alternative investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	0	[4]	0	[4]
Significant Other Observable Inputs (Level 2) [Member] | Commodity derivatives [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	14	[5]	17	[5]
Significant Other Observable Inputs (Level 2) [Member] | Real estate and REITS [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	0	[6]	0	[6]
Significant Unobservable Inputs (Level 3) [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	266		262		191
Significant Unobservable Inputs (Level 3) [Member] | Cash and cash equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	0	[1]	0	[1]
Significant Unobservable Inputs (Level 3) [Member] | Large cap domestic
Defined Benefit Plan Disclosure [Line Items]
Total	0	[2]	0	[2]
Significant Unobservable Inputs (Level 3) [Member] | Small cap domestic [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	0	[2]	0	[2]
Significant Unobservable Inputs (Level 3) [Member] | Large cap international [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	0	[2]	0	[2]
Significant Unobservable Inputs (Level 3) [Member] | Equity derivatives [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	0	[2]	0	[2]
Significant Unobservable Inputs (Level 3) [Member] | Corporate bonds [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	0	[3]	0	[3]
Significant Unobservable Inputs (Level 3) [Member] | Government and agency bonds [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	0	[3]	0	[3]
Significant Unobservable Inputs (Level 3) [Member] | Asset-backed securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	0	[3]	0	[3]
Significant Unobservable Inputs (Level 3) [Member] | Fixed income derivatives [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	0	[3]	0	[3]
Significant Unobservable Inputs (Level 3) [Member] | Alternative investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	266	[4]	262	[4]
Significant Unobservable Inputs (Level 3) [Member] | Commodity derivatives [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	0	[5]	0	[5]
Significant Unobservable Inputs (Level 3) [Member] | Real estate and REITS [Member]
Defined Benefit Plan Disclosure [Line Items]
Total	$ 0	[6]	$ 0	[6]

[1] Consists of cash and institutional short-term investment funds.

[2] Consists of equity securities, equity derivatives, and pooled equity funds.

[3] Consists of corporate and government bonds, asset-backed securities, and fixed income derivatives.

[4] Consists of limited partnerships, private equity and hedge funds.

[5] Consists of long-dated options on a commodity index.

[6] Consists of exchange traded REITS.