Pension and Post-Retirement Benefits - Rate Assumptions Associated with the Pension and Post-Retirement Medical Benefit Plans to Determine Periodic Pension Costs (Details)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
United States
Defined Benefit Plan Disclosure [Line Items]
Discount rate	4.35%	5.05%	5.65%
Expected rate of return on plan assets	8.25%	8.25%	8.25%
Compensation rate increase	3.55%	3.55%	3.60%
International
Defined Benefit Plan Disclosure [Line Items]
Discount rate	3.52%	3.69%	4.40%
Expected rate of return on plan assets	4.98%	4.85%	5.01%
Compensation rate increase	2.95%	3.05%	3.13%
Post-Retirement Medical Benefit Plans
Defined Benefit Plan Disclosure [Line Items]
Discount rate	4.50%	5.25%	5.85%