Parent And Guarantor Consolidating Financial Statements (Schedule Of Condensed Consolidating Statement of Cash Flow) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	$ 1,188	$ 247
Net change in federal funds sold and securities purchased under resale agreements	0	(50)
Purchases of available-for-sale securities	(4,870)	(4,023)
Proceeds from sales of available-for-sale securities	4,175	1,523
Proceeds from maturities and repayment of available-for-sale securities	409	914
Purchases of held-to-maturity securities	(118)	0
Net (increase) decrease in finance receivables and loans	(2,086)	(45)
Proceeds from Sale of Loans Held-for-sale	2,594	1,577
Purchases of operating lease assets	(701)	(1,447)
Disposals of operating lease assets	1,535	1,337
Capital contributions to subsidiaries	0	0
Returns of contributed capital	0	0
Proceeds from sale of business units, net	0	1,049
Increase (Decrease) in Restricted Cash	48	(121)
Net change in nonmarketable equity investments	(315)	58
Other, net	(20)	33
Net cash provided by investing activities	651	805
Net change in short-term borrowings	(2,739)	(618)
Net increase in bank deposits	3,780	2,647
Proceeds from issuance of long-term debt	4,244	8,825
Repayments of long-term debt	(8,490)	(9,778)
Net Change in Debt, Intercompany	0	0
Dividends paid on preferred stock	(15)	(67)
Dividends paid and returns of contributed capital, Intercompany	0	0
Capital contributions from parent	0	0
Net cash (used in) provided by financing activities	(3,220)	1,009
Effect of exchange-rate changes on cash and cash equivalents	2	(1)
Net (decrease) increase in cash and cash equivalents	(1,379)	2,060
Cash and cash equivalents at beginning of period	6,380	5,576
Cash and cash equivalents at end of period	5,001	7,636
Parent [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	(38)	(189)
Net change in federal funds sold and securities purchased under resale agreements		0
Purchases of available-for-sale securities	0	0
Proceeds from sales of available-for-sale securities	0	0
Proceeds from maturities and repayment of available-for-sale securities	0	0
Purchases of held-to-maturity securities	0
Net (increase) decrease in finance receivables and loans	(292)	(242)
Proceeds from Sale of Loans Held-for-sale	0	0
Purchases of operating lease assets	0	0
Disposals of operating lease assets	2	0
Capital contributions to subsidiaries	(128)	(24)
Returns of contributed capital	223	222
Proceeds from sale of business units, net		1,049
Increase (Decrease) in Restricted Cash	0	0
Net change in nonmarketable equity investments	0	0
Other, net	(32)	(1)
Net cash provided by investing activities	456	1,378
Net change in short-term borrowings	187	142
Net increase in bank deposits	(10)	(9)
Proceeds from issuance of long-term debt	178	2,467
Repayments of long-term debt	(580)	(3,161)
Net Change in Debt, Intercompany	(68)	(202)
Dividends paid on preferred stock	(15)	(67)
Dividends paid and returns of contributed capital, Intercompany	0	0
Capital contributions from parent	0	0
Net cash (used in) provided by financing activities	(308)	(830)
Effect of exchange-rate changes on cash and cash equivalents	0	0
Net (decrease) increase in cash and cash equivalents	110	359
Cash and cash equivalents at beginning of period	1,635	2,286
Cash and cash equivalents at end of period	1,745	2,645
Guarantor Subsidiaries [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	0	125
Net change in federal funds sold and securities purchased under resale agreements		0
Purchases of available-for-sale securities	0	0
Proceeds from sales of available-for-sale securities	0	0
Proceeds from maturities and repayment of available-for-sale securities	0	0
Purchases of held-to-maturity securities	0
Net (increase) decrease in finance receivables and loans	0	0
Proceeds from Sale of Loans Held-for-sale	0	0
Purchases of operating lease assets	0	0
Disposals of operating lease assets	0	0
Capital contributions to subsidiaries	0	0
Returns of contributed capital	0	0
Proceeds from sale of business units, net		0
Increase (Decrease) in Restricted Cash	0	0
Net change in nonmarketable equity investments	0	0
Other, net	0	0
Net cash provided by investing activities	0	0
Net change in short-term borrowings	0	0
Net increase in bank deposits	0	0
Proceeds from issuance of long-term debt	0	0
Repayments of long-term debt	0	0
Net Change in Debt, Intercompany	0	0
Dividends paid on preferred stock	0	0
Dividends paid and returns of contributed capital, Intercompany	0	(125)
Capital contributions from parent	0	0
Net cash (used in) provided by financing activities	0	(125)
Effect of exchange-rate changes on cash and cash equivalents	0	0
Net (decrease) increase in cash and cash equivalents	0	0
Cash and cash equivalents at beginning of period	0	0
Cash and cash equivalents at end of period	0	0
Non-Guarantor Subsidiaries [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	1,708	799
Net change in federal funds sold and securities purchased under resale agreements		(50)
Purchases of available-for-sale securities	(4,870)	(4,023)
Proceeds from sales of available-for-sale securities	4,175	1,523
Proceeds from maturities and repayment of available-for-sale securities	409	914
Purchases of held-to-maturity securities	(118)
Net (increase) decrease in finance receivables and loans	(1,794)	197
Proceeds from Sale of Loans Held-for-sale	2,594	1,577
Purchases of operating lease assets	(701)	(1,447)
Disposals of operating lease assets	1,533	(1,337)
Capital contributions to subsidiaries	0	0
Returns of contributed capital	0	0
Proceeds from sale of business units, net		0
Increase (Decrease) in Restricted Cash	48	(121)
Net change in nonmarketable equity investments	(315)	58
Other, net	12	34
Net cash provided by investing activities	929	204
Net change in short-term borrowings	(2,926)	(760)
Net increase in bank deposits	3,790	2,656
Proceeds from issuance of long-term debt	4,066	6,358
Repayments of long-term debt	(7,910)	(6,617)
Net Change in Debt, Intercompany	(684)	(374)
Dividends paid on preferred stock	0	0
Dividends paid and returns of contributed capital, Intercompany	(705)	(586)
Capital contributions from parent	128	24
Net cash (used in) provided by financing activities	(4,241)	701
Effect of exchange-rate changes on cash and cash equivalents	2	(1)
Net (decrease) increase in cash and cash equivalents	(1,602)	1,703
Cash and cash equivalents at beginning of period	5,595	3,905
Cash and cash equivalents at end of period	3,993	5,608
Consolidation, Eliminations [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	(482)	(488)
Net change in federal funds sold and securities purchased under resale agreements		0
Purchases of available-for-sale securities	0	0
Proceeds from sales of available-for-sale securities	0	0
Proceeds from maturities and repayment of available-for-sale securities	0	0
Purchases of held-to-maturity securities	0
Net (increase) decrease in finance receivables and loans	0	0
Proceeds from Sale of Loans Held-for-sale	0	0
Purchases of operating lease assets	0	0
Disposals of operating lease assets	0	0
Capital contributions to subsidiaries	128	24
Returns of contributed capital	(223)	(222)
Proceeds from sale of business units, net		0
Increase (Decrease) in Restricted Cash	0	0
Net change in nonmarketable equity investments	0	0
Other, net	0	0
Net cash provided by investing activities	(734)	(777)
Net change in short-term borrowings	0	0
Net increase in bank deposits	0	0
Proceeds from issuance of long-term debt	0	0
Repayments of long-term debt	0	0
Net Change in Debt, Intercompany	752	576
Dividends paid on preferred stock	0	0
Dividends paid and returns of contributed capital, Intercompany	705	711
Capital contributions from parent	(128)	(24)
Net cash (used in) provided by financing activities	1,329	1,263
Effect of exchange-rate changes on cash and cash equivalents	0	0
Net (decrease) increase in cash and cash equivalents	113	(2)
Cash and cash equivalents at beginning of period	(850)	(615)
Cash and cash equivalents at end of period	(737)	(617)
Affiliated Entity [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Net (increase) decrease in finance receivables and loans	0	0
Affiliated Entity [Member] | Parent [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Net (increase) decrease in finance receivables and loans	683	374
Affiliated Entity [Member] | Guarantor Subsidiaries [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Net (increase) decrease in finance receivables and loans	0	0
Affiliated Entity [Member] | Non-Guarantor Subsidiaries [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Net (increase) decrease in finance receivables and loans	(44)	205
Affiliated Entity [Member] | Consolidation, Eliminations [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Net (increase) decrease in finance receivables and loans	$ (639)	$ (579)