Pension and Other Postretirement Employee Benefit Plans - Weighted-Average Assumptions Benefit Obligations (Details 5) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Defined Benefit Plan Disclosure [Line Items]
Projected Increase In US Defined Benefit Pension And OPEB Plan Expense Resulting From Decreased Discount Rates For Benefit Obligations	48
Minimum [Member]
Weighted-average assumptions used to determine benefit obligations
Investment Advisor Definition of Long Term	10 years
Defined Benefit Plan, Assumed Health Care Cost Trend Rates [Abstract]
Term of iBoxx corporate AA bond index used determining discount rate for the UK defined benefit pension and OPEB plans	15 years
Foreign Pension Plans, Defined Benefit [Member] \| Minimum [Member]
Discount rate:
Defined benefit pension plans and OPEB plans	1.40%	1.50%
Rate of compensation increase	2.75%	2.75%
Foreign Pension Plans, Defined Benefit [Member] \| Maximum [Member]
Discount rate:
Defined benefit pension plans and OPEB plans	4.40%	4.80%
Rate of compensation increase	4.10%	4.20%
Defined Benefit Pension Plans, U.S. [Member]
Discount rate:
Defined benefit pension plans and OPEB plans	3.90%	4.60%
OPEB plans, U.S. [Member]
Discount rate:
Defined benefit pension plans and OPEB plans	3.90%	4.70%
OPEB plans, Non-U.S. [Member]
Discount rate:
Defined benefit pension plans and OPEB plans	0.00%	0.00%
Pension and other postretirement employee benefit plans, U.S. [Member]
Discount rate:
Rate of compensation increase	4.00%	4.00%
Defined Benefit Plan, Assumed Health Care Cost Trend Rates [Abstract]
Assumed for next year	7.00%	7.00%	7.75%
Ultimate	5.00%	5.00%	5.00%
Year when rate will reach ultimate	2017	2017	2014
Foreign Pension Plans and Other Foreign Postretirement Benefit Plans [Member]
Defined Benefit Plan, Assumed Health Care Cost Trend Rates [Abstract]
Assumed for next year	0.00%	0.00%	0.00%
Ultimate	0.00%	0.00%	0.00%

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Period of Time Used to Project Long-Term Returns for Defined Benefit Pension and OPEB Plans

+ References

No definition available.

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- Definition

Projected Increase In US Defined Benefit Pension And OPEB Plan Expense Resulting From Decreased Discount Rates For Benefit Obligations

+ References

No definition available.

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- Definition

Term of iBoxx corporate "AA" bond index used determining discount rate for the U.K. defined benefit pension and OPEB plans.

+ References

No definition available.

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- Definition

The interest rate used to adjust for the time value of money for the plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

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-Section 50

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- Definition

Expected rate of compensation increases (for pay-related plans).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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- Definition

The assumed health care cost trend rate for the next year used to measure the expected cost of benefits covered by the plan (gross eligible charges). This is based upon the annual rate of change in the cost of health care benefits currently provided by the postretirement benefit plan, due to factors other than changes in the composition of the plan population by age and dependency status.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

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-Paragraph 1

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Health Care Cost Trend Rate

-URI http://asc.fasb.org/extlink&oid=6514820

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- Definition

The ultimate trend rate for health care costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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- Definition

Year the ultimate health care cost trend rate is expected to be reached, in CCYY format.

+ References

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-Publisher FASB

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