Pension and Other Postretirement Employee Benefit Plans - Weighted Average Asset Allocation (Details 8) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
US Pension Plans and Other US Postretirement Employee Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan Amount Of Plan Investments Held In Funds That Are Sponsored Or Managed By Affiliates Of Entity	1,800	1,600
Defined Benefit Pension Plans, U.S. [Member]
Asset category
Actual plan asset allocations	100.00%	100.00%
Target plan asset allocations	100.00%
Real estate - % of plan assets	100.00%	100.00%
Defined Benefit Pension Plans, U.S. [Member] | Debt Securities [Member]
Asset category
Actual plan asset allocations	20.00%	20.00%
Real estate - % of plan assets	20.00%	20.00%
Defined Benefit Pension Plans, U.S. [Member] | Equity Securities [Member]
Asset category
Actual plan asset allocations	41.00%	39.00%
Real estate - % of plan assets	41.00%	39.00%
Defined Benefit Pension Plans, U.S. [Member] | Real Estate [Member]
Asset category
Actual plan asset allocations	5.00%	5.00%
Real estate - % of plan assets	5.00%	5.00%
Defined Benefit Pension Plans, U.S. [Member] | Alternative Investments [Member]
Asset category
Actual plan asset allocations	34.00%	36.00%
Real estate - % of plan assets	34.00%	36.00%
Defined Benefit Pension Plans, Non-U.S. [Member]
Asset category
Actual plan asset allocations	100.00%	100.00%
Target plan asset allocations	100.00%
Real estate - % of plan assets	100.00%	100.00%
Defined Benefit Pension Plans, Non-U.S. [Member] | Debt Securities [Member]
Asset category
Actual plan asset allocations	72.00%	74.00%
Target plan asset allocations	70.00%
Real estate - % of plan assets	72.00%	74.00%
Defined Benefit Pension Plans, Non-U.S. [Member] | Equity Securities [Member]
Asset category
Actual plan asset allocations	27.00%	25.00%
Target plan asset allocations	29.00%
Real estate - % of plan assets	27.00%	25.00%
Defined Benefit Pension Plans, Non-U.S. [Member] | Real Estate [Member]
Asset category
Actual plan asset allocations	0.00%	0.00%
Target plan asset allocations	0.00%
Real estate - % of plan assets	0.00%	0.00%
Defined Benefit Pension Plans, Non-U.S. [Member] | Alternative Investments [Member]
Asset category
Actual plan asset allocations	1.00%	1.00%
Target plan asset allocations	1.00%
Real estate - % of plan assets	1.00%	1.00%
OPEB Plans [Member]
Asset category
Actual plan asset allocations	100.00%	100.00%
Target plan asset allocations	100.00%
Real estate - % of plan assets	100.00%	100.00%
OPEB Plans [Member] | Debt Securities [Member]
Asset category
Actual plan asset allocations	50.00%	50.00%
Target plan asset allocations	50.00%
Real estate - % of plan assets	50.00%	50.00%
OPEB Plans [Member] | Equity Securities [Member]
Asset category
Actual plan asset allocations	50.00%	50.00%
Target plan asset allocations	50.00%
Real estate - % of plan assets	50.00%	50.00%
OPEB Plans [Member] | Real Estate [Member]
Asset category
Actual plan asset allocations	0.00%	0.00%
Target plan asset allocations	0.00%
Real estate - % of plan assets	0.00%	0.00%
OPEB Plans [Member] | Alternative Investments [Member]
Asset category
Actual plan asset allocations	0.00%	0.00%
Target plan asset allocations	0.00%
Real estate - % of plan assets	0.00%	0.00%
Foreign Pension Plans and Other Foreign Postretirement Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan Amount Of Plan Investments Held In Funds That Are Sponsored Or Managed By Affiliates Of Entity	220	194
Minimum [Member] | Defined Benefit Pension Plans, U.S. [Member] | United States Equity Securities Member [Member]
Asset category
Target Allocation, Minimum	15.00%
Minimum [Member] | Defined Benefit Pension Plans, U.S. [Member] | International Equity Securities [Member]
Asset category
Target Allocation, Minimum	15.00%
Minimum [Member] | Defined Benefit Pension Plans, U.S. [Member] | Hedge Funds [Member]
Asset category
Target Allocation, Minimum	10.00%
Minimum [Member] | Defined Benefit Pension Plans, U.S. [Member] | Real Estate, Real Assets and Private Equity [Member]
Asset category
Target Allocation, Minimum	5.00%
Minimum [Member] | Defined Benefit Pension Plans, U.S. [Member] | Equity Securities [Member]
Asset category
Target Allocation, Minimum	25.00%
Minimum [Member] | Defined Benefit Pension Plans, U.S. [Member] | Real Estate [Member]
Asset category
Target Allocation, Minimum	5.00%
Minimum [Member] | Defined Benefit Pension Plans, U.S. [Member] | Alternative Investments [Member]
Asset category
Target Allocation, Minimum	15.00%
Maximum [Member] | Defined Benefit Pension Plans, U.S. [Member] | United States Equity Securities Member [Member]
Asset category
Target Allocation, Maximum	35.00%
Maximum [Member] | Defined Benefit Pension Plans, U.S. [Member] | International Equity Securities [Member]
Asset category
Target Allocation, Maximum	25.00%
Maximum [Member] | Defined Benefit Pension Plans, U.S. [Member] | Hedge Funds [Member]
Asset category
Target Allocation, Maximum	30.00%
Maximum [Member] | Defined Benefit Pension Plans, U.S. [Member] | Real Estate, Real Assets and Private Equity [Member]
Asset category
Target Allocation, Maximum	20.00%
Maximum [Member] | Defined Benefit Pension Plans, U.S. [Member] | Equity Securities [Member]
Asset category
Target Allocation, Maximum	60.00%
Maximum [Member] | Defined Benefit Pension Plans, U.S. [Member] | Real Estate [Member]
Asset category
Target Allocation, Maximum	20.00%
Maximum [Member] | Defined Benefit Pension Plans, U.S. [Member] | Alternative Investments [Member]
Asset category
Target Allocation, Maximum	50.00%
Debt Securities [Member] | Minimum [Member] | Defined Benefit Pension Plans, U.S. [Member]
Asset category
Target Allocation, Minimum	10.00%
Debt Securities [Member] | Maximum [Member] | Defined Benefit Pension Plans, U.S. [Member]
Asset category
Target Allocation, Maximum	30.00%