Commitments and Contingencies Guarantees (Details) - USD ($)	6 Months Ended
	Jun. 30, 2015	Dec. 31, 2014
Customer Lines Of Credit For Brazilian Subsidiary
Guarantor Obligations [Line Items]
Guarantor obligations, maximum exposure, undiscounted	$ 352,000,000	$ 492,000,000
Guarantee of Indebtedness of Others
Guarantor Obligations [Line Items]
Guarantor obligations, maximum exposure, undiscounted	2,100,000,000.0	$ 2,600,000,000
Line of Credit
Guarantor Obligations [Line Items]
Guarantor obligations, maximum exposure, undiscounted	$ 45,000,000
Guarantor obligations, term	5 years