Goodwill and Mortgage Servicing Rights - Mortgage Fees and Related Income (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Risk management:
All other	$ 2	$ 3	$ 1
Mortgage fees and related income	1,254	1,616	2,491
Consumer & Community Banking
CCB mortgage fees and related income
Net production revenue	268	636	853
Operating revenue:
Loan servicing revenue	1,835	2,014	2,336
Changes in MSR asset fair value due to collection/realization of expected cash flows	(740)	(795)	(916)
Total operating revenue	1,095	1,219	1,420
Risk management:
Changes in MSR asset fair value due to market interest rates and other	300	(202)	(72)
Other changes in MSR asset fair value due to other inputs and assumptions in model	(70)	(30)	(91)
Change in derivative fair value and other	(341)	(10)	380
Total risk management	(111)	(242)	217
Total net mortgage servicing revenue	984	977	1,637
Mortgage fees and related income	$ 1,252	$ 1,613	$ 2,490