Commitments, Contingencies and Other Items - Lawsuits (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Jun. 30, 2014
Loss Contingencies
Estimated Litigation Liability		$ 220
Peruvian Tax Litigation | Pending Litigation
Loss Contingencies
Loss Contingency, Asserted Claim		59
Loss Contingency Accrual, Period Increase (Decrease)	28
Peruvian Tax Litigation, Before Interest | Pending Litigation
Loss Contingencies
Loss Contingency, Asserted Claim		26
Peruvian Tax Litigation, Income Tax witholding 2001 and 2002 | Pending Litigation
Loss Contingencies
Loss Contingency, Asserted Claim		3
Peruvian Tax Litigation, VAT for 2001 and 2002 | Pending Litigation
Loss Contingencies
Loss Contingency, Asserted Claim		7
Peruvian Tax Litigation, Disallowance of VAT in 2005 | Pending Litigation
Loss Contingencies
Loss Contingency, Asserted Claim		16
Employee Severance and Contractor Termination Disputes | Pending Litigation
Loss Contingencies
Loss Contingency, Asserted Claim		43
up to | Brazilian Tax Claims | Pending Litigation
Loss Contingencies
Loss Contingency, Range of Possible Loss, Portion Not Accrued		$ 69