Variable Interest Entities - Unconsolidated VIEs (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Unconsolidated Assets
Interest Bearing Deposits in Banks		$ 9,830		$ 7,184
Securities Available for Sale		15,140		17,789
Loans held for investment	[1]	89,786		88,213
Other Assets		11,791		10,200
Total assets		165,696	$ 170,707	170,810
Unconsolidated Liabilities
Other Liabilities		3,317		2,837
Total liabilities		149,164		154,443
Unconsolidated VIEs
Unconsolidated Assets
Securities Available for Sale		27		27
Loans held for investment		238		232
Other Assets		2,292		2,197
Total assets		2,557		2,456
Unconsolidated Liabilities
Other Liabilities		193		152
Total liabilities		193		152
Maximum Exposure to Loss		2,654		2,557
Unconsolidated VIEs | LIHC investments
Variable Interest Entities
Liabilities Assumed		52	$ 55
Unconsolidated Assets
Securities Available for Sale		27		27
Loans held for investment		231		219
Other Assets		898		872
Total assets		1,156		1,118
Unconsolidated Liabilities
Other Liabilities		189		148
Total liabilities		189		148
Maximum Exposure to Loss		1,156		1,118
Unconsolidated VIEs | Leasing investments
Unconsolidated Assets
Securities Available for Sale		0		0
Loans held for investment		0		0
Other Assets		1,321		1,256
Total assets		1,321		1,256
Unconsolidated Liabilities
Other Liabilities		0		0
Total liabilities		0		0
Maximum Exposure to Loss		1,341		1,276
Unconsolidated VIEs | Other investments
Unconsolidated Assets
Securities Available for Sale		0		0
Loans held for investment		7		13
Other Assets		73		69
Total assets		80		82
Unconsolidated Liabilities
Other Liabilities		4		4
Total liabilities		4		4
Maximum Exposure to Loss		$ 157		$ 163

[1] Includes $279 million and $320 million at March 31, 2020 and December 31, 2019, respectively, for net unamortized (discounts) and premiums and deferred (fees) and costs.Accrued interest receivable on loans held for investment and securities totaled $469 million at March 31, 2020 and is included in the other assets on the consolidated balance sheet.