Income Taxes And Tax-Related Items Principal Components of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Deferred Tax Assets, Operating Lease Liability	$ 77	$ 0
Document Period End Date	Dec. 31, 2019
Deferred tax assets:
Allowance for loan losses	$ 134	141
Deferred compensation	61	68
Deferred loan origination fees and costs	8	9
Net unrealized losses on investment securities available-for-sale	0	42
Other temporary differences, net	49	42
Total deferred tax asset before valuation allowance	329	302
Valuation allowance	(3)	(3)
Total deferred tax assets	326	299
Deferred tax liabilities:
Lease financing transactions	(73)	(74)
Deferred Tax Liability, net unrealized gains on investment securities available-for-sale	(20)	0
Defined benefit plans	(91)	(41)
Allowance for depreciation	(21)	(18)
Deferred Tax Liability, Hedging gains and losses	(10)	0
Leasing right of use asset	(69)	0
Total deferred tax liabilities	(284)	(133)
Net deferred tax asset	$ 42	$ 166