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Equity Securities Classified as Other Assets, Fair Value Disclosure

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Other Assets, Fair Value Disclosure [Abstract]

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Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount of unrealized gain (loss) on investment in debt and equity securities.

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Amount excluding accrued interest, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Carrying amount as of the balance sheet date of assets held under deferred compensation agreements.

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Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and elected not to be offset.

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Fair value of liability associated with financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, and obligation to return cash collateral under master netting arrangements.

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Fair value of asset associated with financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, and right to receive cash collateral under master netting arrangements.

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Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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Fair value portion of other assets.

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Fair value portion of interest continued to be held by a transferor after transferring financial assets to a third party.

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Fair Value Measurement - Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2022	Dec. 31, 2021	Mar. 31, 2021
Assets:
Securities available for sale	$ 89,076	$ 95,261
Loans Held-for-sale, Fair Value Disclosure	928	1,000
Derivative assets, gross amount	4,519	2,690
Derivative asset, netting adjustments	(761)	(542)
Derivative asset	3,758	2,148
Liabilities:
Derivative liabilities, gross amount	4,853	1,868
Derivative liability, netting adjustments	(1,282)	(544)
Derivative liability	3,571	1,324
Net valuation allowance	10	11
Level 1
Assets:
Loans Held-for-sale, Fair Value Disclosure	0	0
Level 2
Assets:
Loans Held-for-sale, Fair Value Disclosure	227	5,091
Level 3
Assets:
Loans Held-for-sale, Fair Value Disclosure	0	0
Recurring
Assets:
Securities available for sale	89,076	95,261
Loans Held-for-sale, Fair Value Disclosure	928	1,026
Derivative asset	3,758	2,148
Other assets	568	573
Total assets	94,330	99,008
Liabilities:
Derivative liability	3,571	1,324
Recurring \| Level 1
Assets:
Securities available for sale	9,700	9,648
Loans Held-for-sale, Fair Value Disclosure	0	0
Derivative assets, gross amount	1,106	406
Other assets	525	526
Total assets	11,331	10,580
Other assets:
Deferred compensation plan assets	494	490
Liabilities:
Derivative liabilities, gross amount	2,225	838
Recurring \| Level 2
Assets:
Securities available for sale	79,144	85,346
Loans Held-for-sale, Fair Value Disclosure	928	1,026
Derivative assets, gross amount	3,211	2,200
Other assets	4	6
Total assets	83,287	88,578
Liabilities:
Derivative liabilities, gross amount	2,448	965
Recurring \| Level 3
Assets:
Securities available for sale	232	267
Loans Held-for-sale, Fair Value Disclosure	0	0
Derivative assets, gross amount	202	84	$ 157
Other assets	39	41
Total assets	473	392
Other assets:
Retained interests in securitizations	39	41
Liabilities:
Derivative liabilities, gross amount	180	65	$ 123
Recurring \| Fair Value Inputs Level 1 And Level 2 [Member]
Other assets:
Equity securities	35	42
Liabilities:
Debt and Equity Securities, Unrealized Gain (Loss)	(5)	(36)
U.S. Treasury securities
Assets:
Securities available for sale	9,497	9,442
U.S. Treasury securities \| Recurring
Assets:
Securities available for sale	9,497	9,442
U.S. Treasury securities \| Recurring \| Level 1
Assets:
Securities available for sale	9,497	9,442
U.S. Treasury securities \| Recurring \| Level 2
Assets:
Securities available for sale	0	0
U.S. Treasury securities \| Recurring \| Level 3
Assets:
Securities available for sale	0	0
RMBS
Assets:
Securities available for sale	68,425	73,616
RMBS \| Recurring
Assets:
Securities available for sale	68,425	73,616
RMBS \| Recurring \| Level 1
Assets:
Securities available for sale	0	0
RMBS \| Recurring \| Level 2
Assets:
Securities available for sale	68,214	73,358
RMBS \| Recurring \| Level 3
Assets:
Securities available for sale	211	258
CMBS \| Recurring
Assets:
Securities available for sale	8,365	9,369
CMBS \| Recurring \| Level 1
Assets:
Securities available for sale	0	0
CMBS \| Recurring \| Level 2
Assets:
Securities available for sale	8,344	9,360
CMBS \| Recurring \| Level 3
Assets:
Securities available for sale	21	9
Other securities
Assets:
Securities available for sale	2,789	2,834
Other securities \| Recurring
Assets:
Securities available for sale	2,789	2,834
Other securities \| Recurring \| Level 1
Assets:
Securities available for sale	203	206
Other securities \| Recurring \| Level 2
Assets:
Securities available for sale	2,586	2,628
Other securities \| Recurring \| Level 3
Assets:
Securities available for sale	$ 0	$ 0