Employee Benefit Plans - Assumptions, Market-Related Value, and Unrecognized Loss (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Total Pension Benefits [Member]
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Discount rate	3.70%	4.00%
Rate of compensation increase	2.50%	3.00%
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Discount rate	4.00%	5.00%	5.40%
Expected return on plan assets	4.80%	6.30%	6.90%
Rate of compensation increase	3.00%	3.50%	3.70%
U.S. Pension Benefits [Member]
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Discount rate	3.80%	4.00%
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Discount rate	4.00%	5.30%	5.80%
Expected return on plan assets	4.80%	6.80%	7.50%
International Pension Benefits [Member]
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Discount rate	3.70%	4.10%
Rate of compensation increase	2.50%	3.00%
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Discount rate	4.10%	4.60%	4.90%
Expected return on plan assets	4.80%	5.50%	6.00%
Rate of compensation increase	3.00%	3.50%	3.70%
Postemployment Benefits [Member]
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Discount rate	2.90%	3.50%
Rate of compensation increase	2.60%	3.20%
Involuntary turnover rate	5.50%	5.50%
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Discount rate	3.50%	3.90%	4.30%
Rate of compensation increase	3.20%	3.40%	3.60%
Involuntary turnover rate	5.50%	5.50%	5.00%
Postretirement Benefits [Member]
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Discount rate	2.60%	3.30%
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Discount rate	3.30%	4.30%	5.00%
Defined Benefit Plan, Effect of One-Percentage Point Change in Assumed Health Care Cost Trend Rates [Abstract]
Effect of one percentage point increase on service and interest cost	$ 0
Effect of one percentage point decrease on service and interest cost	0
Effect of one percentage point increase on accumulated postretirement benefit obligation	1
Effect of one percentage point decrease on accumulated postretirement benefit obligation	$ (1)
Postretirement Benefits [Member] \| Pre-65 Coverage [Member]
Defined Benefit Plan, Assumed Health Care Cost Trend Rates [Abstract]
Healthcare cost trend rate assumed for next year	8.00%	9.00%
Rate to which the cost trend rate is assumed to decline (the ultimate trend rate)	5.00%	5.00%
Year that the rate reaches the ultimate rate	2018	2018
Postretirement Benefits [Member] \| Post-65 Coverage[Member]
Defined Benefit Plan, Assumed Health Care Cost Trend Rates [Abstract]
Healthcare cost trend rate assumed for next year	6.50%	7.00%
Rate to which the cost trend rate is assumed to decline (the ultimate trend rate)	5.00%	5.00%
Year that the rate reaches the ultimate rate	2018	2018

Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Involuntary Turnover Rate

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- Definition

Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Involuntary Turnover Rate

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- Definition

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

+ References

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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

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

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- Definition

An assumption as to the rate of return on plan assets reflecting the average rate of earnings expected on the funds invested or to be invested to provide for the benefits included in the benefit obligation.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 87

-Paragraph 264

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher FASB

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 30

-Glossary Expected Long-Term Rate of Return on Plan Assets

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- Definition

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

+ References

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- Definition

Amount of effect of a one-percentage-point decrease in the assumed health care cost trend rates on the accumulated postretirement benefit obligation for health care benefits.

+ References

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Amount of effect of a one-percentage-point decrease in the assumed health care cost trend rates on the aggregate of the service and interest cost components of net periodic postretirement health care benefit costs.

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The effect of a one-percentage-point increase in the assumed health care cost trend rates on the accumulated postretirement benefit obligation for health care benefits.

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The effect of a one-percentage-point increase in the assumed health care cost trend rates on the aggregate of the service and interest cost components of net periodic postretirement health care benefit costs.

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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.

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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

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The ultimate trend rate for health care costs.

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

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-Name Accounting Standards Codification

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