Intangible Assets, Amortization Expense (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Finite-Lived Intangible Assets, Future Amortization Expense, Current and Five Succeeding Fiscal Years [Abstract]
Six months ended June 30, 2017 (actual)	$ 287	$ 299	$ 576	$ 592
Estimate for the remainder of 2017	700		700
Estimate for year ended December 31,
2018	1,289		1,289
2019	309		309
2020	273		273
2021	235		235
2022	203		203
Finite lived intangible assets [Member]
Finite-Lived Intangible Assets, Future Amortization Expense, Current and Five Succeeding Fiscal Years [Abstract]
Six months ended June 30, 2017 (actual)			716
Amortized MSRs [Member]
Finite-Lived Intangible Assets, Future Amortization Expense, Current and Five Succeeding Fiscal Years [Abstract]
Six months ended June 30, 2017 (actual)			133
Estimate for the remainder of 2017	127		127
Estimate for year ended December 31,
2018	227		227
2019	201		201
2020	184		184
2021	159		159
2022	140		140
Core deposit intangibles [Member]
Finite-Lived Intangible Assets, Future Amortization Expense, Current and Five Succeeding Fiscal Years [Abstract]
Six months ended June 30, 2017 (actual)			427
Estimate for the remainder of 2017	424		424
Estimate for year ended December 31,
2018	769		769
2019
2020
2021
2022
Customer relationship and other amortized intangibles [Member]
Finite-Lived Intangible Assets, Future Amortization Expense, Current and Five Succeeding Fiscal Years [Abstract]
Six months ended June 30, 2017 (actual)			156
Estimate for the remainder of 2017	149		149
Estimate for year ended December 31,
2018	293		293
2019	108		108
2020	89		89
2021	76		76
2022	$ 63		63
Lease agreement intangibles [Member]
Finite-Lived Intangible Assets, Future Amortization Expense, Current and Five Succeeding Fiscal Years [Abstract]
Six months ended June 30, 2017 (actual)			$ 7