Credit Quality And Allowance For Credit Losses (Changes In The Allowance For Loan Losses And Related Loan Amounts) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Dec. 31, 2014	Jun. 30, 2014
Financing Receivable, Allowance for Credit Losses [Line Items]
Provision for loan losses	$ 47	$ 11	$ 61	$ 20
Purchased credit impaired (PCI) loans					$ 2	$ 2
Total loans					49,741	48,593
Business loans
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans					45,398	44,380
Retail loans
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans					$ 4,343	4,213
Financing Receivable [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance at beginning of period	601	594	594	598
Loan charge-offs	(35)	(28)	(58)	(58)
Recoveries on loans previously charged-off	17	19	32	37
Net loan charge-offs	(18)	(9)	(26)	(21)
Provision for loan losses	35	6	51	14
Foreign currency translation adjustment			(1)	0
Balance at end of period	618	591	618	591
As a percentage of total loans					1.24%		1.23%
Allowance for loan losses individually evaluated for impairment					$ 39		$ 39
Allowance for loan losses collectively evaluated for impairment					579		552
Total allowance for loan losses	601	594	594	598	618	594	591
Loans individually evaluated for impairment					292		260
Loans collectively evaluated for impairment					49,447		47,619
Purchased credit impaired (PCI) loans					2		3
Total loans					$ 49,741		$ 47,882
Financing Receivable [Member] | Business loans
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance at beginning of period	541	530	534	531
Loan charge-offs	(31)	(24)	(52)	(51)
Recoveries on loans previously charged-off	16	15	28	31
Net loan charge-offs	(15)	(9)	(24)	(20)
Provision for loan losses	37	7	54	17
Foreign currency translation adjustment			(1)	0
Balance at end of period	563	528	563	528
As a percentage of total loans					1.24%		1.21%
Allowance for loan losses individually evaluated for impairment					$ 39		$ 39
Allowance for loan losses collectively evaluated for impairment					524		489
Total allowance for loan losses	541	530	534	531	563	534	528
Loans individually evaluated for impairment					258		215
Loans collectively evaluated for impairment					45,140		43,631
Purchased credit impaired (PCI) loans					0		0
Total loans					$ 45,398		$ 43,846
Financing Receivable [Member] | Retail loans
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance at beginning of period	60	64	60	67
Loan charge-offs	(4)	(4)	(6)	(7)
Recoveries on loans previously charged-off	1	4	4	6
Net loan charge-offs	(3)	0	(2)	(1)
Provision for loan losses	(2)	(1)	(3)	(3)
Foreign currency translation adjustment			0	0
Balance at end of period	55	63	55	63
As a percentage of total loans					1.27%		1.55%
Allowance for loan losses individually evaluated for impairment					$ 0		$ 0
Allowance for loan losses collectively evaluated for impairment					55		63
Total allowance for loan losses	$ 60	$ 64	$ 60	$ 67	55	$ 60	63
Loans individually evaluated for impairment					34		45
Loans collectively evaluated for impairment					4,307		3,988
Purchased credit impaired (PCI) loans					2		3
Total loans					$ 4,343		$ 4,036