Accounts Payable and Accrued Expenses (Details) (USD $) In Millions, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Accounts payable and accrued expenses
Accounts payable	$ 286	$ 331
Subservicing advance liabilities	273	24
Repurchase eligible loans	90	99
Accrued payroll and benefits	67	80
Accrued interest	16	32
Other	18	20
Total	750	586
Mortgage loan unpaid principal balance of assumed subservicing portfolio	227,973	183,730
New subservicing portfolio
Accounts payable and accrued expenses
Subservicing advance liabilities	240
Mortgage loan unpaid principal balance of assumed subservicing portfolio	47,000
Servicing advance receivables	$ 254