Finance Receivables - Narrative (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014	Dec. 31, 2013
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	$ 581	$ 682
Consumer Finance Receivables [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	25,591	25,623
Consumer Finance Receivables [Member] | North America Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	14,294	13,361
Consumer Finance Receivables [Member] | Deteriorated Credit Quality [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	344
Commercial Finance Receivables [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	7,607	8,072	7,108	6,700
Commercial Finance Receivables [Member] | North America Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	$ 3,260	$ 3,180	$ 2,190	$ 1,975