Consolidated Statement Of Cash Flows (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Net Cash Provided by (Used in) Operating Activities [Abstract]
Net income (loss)	$ 576	$ 227
Depreciation, Amortization and Accretion, Net	759	738
Provision for Loan Losses Expensed Including Discontinued Operations	116	137
Gain Loss on Sales of Loans Net Including Discontinued Operations	(46)	0
Available-for-sale Securities Gross Realized Gain Loss Excluding Otti Including Disc Ops	(55)	(43)
Gains (Losses) on Extinguishment of Debt	198	39
Payments for Origination and Purchases of Loans Held-for-sale	(1,241)	0
Proceeds from Sale of Loans Held-for-sale	125	13
Total Charge Recorded Related to ResCap Bankruptcy	0	(26)
Discontinued Operation, Gain (Loss) from Disposal of Discontinued Operation, before Income Tax	(452)	0
Deferred income taxes	165	68
Interest payable	(37)	5
Other assets	396	191
Other liabilities	(92)	(368)
Other, net	(165)	(49)
Net cash provided by (used in) operating activities	247	932
Net Cash Provided by (Used in) Investing Activities [Abstract]
Proceeds from (Payments for) Federal Funds Sold and Securities Purchased under Agreements to Resell, Net	(50)	0
Purchases of available-for-sale securities	(4,023)	(907)
Proceeds from sales of available-for-sale securities	1,523	1,354
Proceeds from maturities of available-for-sale securities	914	592
Net (increase) decrease in finance receivables and loans	(45)	492
Proceeds from Sale of Loans Held-for-investment	1,577	0
Purchases of operating lease assets	(1,447)	(2,360)
Disposals of operating lease assets	1,337	1,285
Proceeds from sale of business units, net	1,049	0
Increase (Decrease) in Restricted Cash	(121)	1,580
Other, net	91	111
Net cash (used in) provided by investing activities	805	2,147
Net Cash Provided by (Used in) Financing Activities [Abstract]
Net change in short-term borrowings	(618)	(3,384)
Net increase in bank deposits	2,652	2,017
Proceeds from issuance of long-term debt	8,820	9,402
Repayments of long-term debt	(9,778)	(10,683)
Dividends paid	(67)	(68)
Net cash provided by (used in) financing activities	1,009	(2,716)
Effect of exchange-rate changes on cash and cash equivalents	(1)	(1)
Cash and Cash Equivalents, Period Increase (Decrease)	2,060	362
Cash and cash equivalents at beginning of period	5,576	5,531
Cash and cash equivalents at end of period	7,636	5,893
Supplemental Cash Flow Information [Abstract]
Interest	641	664
Income taxes	95	(6)
Transfer of Portfolio Loans and Leases to Held-for-sale	69	40
Proceeds from sales and repayments of mortgage loans held-for-investment originally designated as held-for-sale	$ 43	$ 7