Consolidated Statements of Cash Flows - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
Cash Flows from Operating Activities:
Net income including noncontrolling interests	$ 472	$ 649
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Provision for credit losses	36	7
Depreciation, amortization and accretion, net	299	224
Stock-based compensation—restricted stock units	33	24
Deferred income taxes	109	86
Net gains on sales of securities	(14)	(16)
Net decrease (increase) in trading account assets	(86)	(31)
Net decrease (increase) in other assets	117	265
Net increase (decrease) in trading account liabilities	(3)	56
Net increase (decrease) in other liabilities	(61)	(150)
Loans originated for sale	(914)	(599)
Net proceeds from sale of loans originated for sale	910	573
Pension and other postretirement benefits adjustment	(122)	(80)
Other, net	3	(19)
Total adjustments	307	340
Net cash provided by (used in) operating activities	779	989
Cash Flows from Investing Activities:
Proceeds from sales of securities available for sale	(1,528)	(1,200)
Proceeds from paydowns and maturities of securities available for sale	1,494	1,789
Purchases of securities available for sale	(3,498)	(894)
Proceeds from paydowns and maturities of securities held to maturity	1,432	773
Purchases of securities held to maturity	(3,492)	(2,733)
Proceeds from sales of loans	860	84
Net decrease (increase) in loans	(748)	(6,387)
Purchases of other investments	(273)	(415)
Other, net	(105)	(80)
Net cash provided by (used in) investing activities	(2,802)	(6,663)
Cash Flows from Financing Activities:
Net increase (decrease) in deposits	(3,311)	2,255
Net increase (decrease) in commercial paper and other short-term borrowings	(366)	1,313
Proceeds from issuance of long-term debt	5,197	749
Repayment of long-term debt	(817)	(305)
Other, net	(56)	(22)
Change in noncontrolling interests	(1)	0
Net cash provided by (used in) financing activities	646	3,990
Net change in cash and cash equivalents	(1,377)	(1,684)
Cash and cash equivalents at beginning of period	5,751	6,203
Cash and cash equivalents at end of period	4,374	4,519
Cash Paid During the Period For:
Interest	312	294
Income taxes, net	64	19
Supplemental Schedule of Noncash Investing and Financing Activities:
Net transfer of loans held for investment to loans held for sale	867	96
Transfer of loans held for investment to other real estate owned assets	12	11
Transfer of assets and liabilities from BTMU:
Carrying amount of assets acquired	0	70
Carrying amount of liabilities assumed	$ 0	$ 30