Debt and Borrowing Arrangements (Details 2) (USD $) In Millions, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Debt and Borrowing Arrangements
Restricted cash and cash equivalents	$ 349	$ 304
Accounts receivable	972	797
Mortgage loans held for sale (unpaid principal balance)	1,751	2,174
Net investment in fleet leases	3,736	3,636
Vehicle Asset-Backed Debt \| Assets held as collateral
Debt and Borrowing Arrangements
Restricted cash and cash equivalents	294
Accounts receivable	64
Net investment in fleet leases	3,678
Total	4,036
Mortgage Asset-Backed Debt \| Assets held as collateral
Debt and Borrowing Arrangements
Restricted cash and cash equivalents	9
Accounts receivable	81
Mortgage loans held for sale (unpaid principal balance)	1,630
Total	$ 1,720

Carrying amount of mortgage loans to individuals not classified as held for investment but are held-for-sale.

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The carrying amount, as of the date of the latest financial statement presented, of all assets that are pledged as collateral for the payment of the related debt obligation primarily arising from secured borrowings, repurchase agreements or other current or potential obligations, where the secured party does not have the right by contract or custom to sell or re-pledge the collateral and therefore are not reclassified and separately reported in the statement of financial position.

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- Definition

The carrying amounts of cash and cash equivalent items which are restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits; however, time deposits and short-term certificates of deposit are not generally included in legally restricted deposits. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet. This element is for unclassified presentations; for classified presentations there is a separate and distinct element.

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