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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	9 Months Ended	12 Months Ended
	Sep. 30, 2021	Dec. 31, 2020	Sep. 30, 2020
Assets:
Securities available for sale (amortized cost of $97.0 billion and $97.6 billion and allowance for credit losses of $1 million as of both September 30, 2021 and December 31, 2020)	$ 98,149	$ 100,445
Loans held for sale	1,700	596
Derivative assets, gross amount	4,904	3,415
Derivative asset, netting adjustments	(975)	(1,148)
Derivative asset	3,929	2,267
Liabilities:
Derivative liabilities, gross amount	3,463	1,518
Derivative liability, netting adjustments	(904)	(739)
Derivative liability	2,559	779
Net valuation allowance	17	31
Level 1
Assets:
Loans held for sale	0	0
Level 2
Assets:
Loans held for sale	4,880	2,214
Level 3
Assets:
Loans held for sale	0	0
Recurring
Assets:
Securities available for sale (amortized cost of $97.0 billion and $97.6 billion and allowance for credit losses of $1 million as of both September 30, 2021 and December 31, 2020)	98,149	100,445
Loans held for sale	1,707	596
Derivative asset	3,929	2,267
Other assets	573	1,037
Total assets	104,358	104,345
Liabilities:
Derivative liability	2,559	779
Recurring \| Level 1
Assets:
Securities available for sale (amortized cost of $97.0 billion and $97.6 billion and allowance for credit losses of $1 million as of both September 30, 2021 and December 31, 2020)	9,261	9,460
Loans held for sale	0	0
Derivative assets, gross amount	955	268
Other assets	514	430
Total assets	10,730	10,158
Other assets:
Deferred compensation plan assets	463	414
Liabilities:
Derivative liabilities, gross amount	1,904	271
Recurring \| Level 2
Assets:
Securities available for sale (amortized cost of $97.0 billion and $97.6 billion and allowance for credit losses of $1 million as of both September 30, 2021 and December 31, 2020)	88,626	90,546
Loans held for sale	1,707	596
Derivative assets, gross amount	3,758	3,006
Other assets	16	552
Total assets	94,107	94,700
Liabilities:
Derivative liabilities, gross amount	1,407	1,137
Recurring \| Level 3
Assets:
Securities available for sale (amortized cost of $97.0 billion and $97.6 billion and allowance for credit losses of $1 million as of both September 30, 2021 and December 31, 2020)	262	439
Loans held for sale	0	0
Derivative assets, gross amount	191	141	$ 153
Other assets	43	55
Total assets	496	635
Other assets:
Retained interests in securitizations	43	55
Liabilities:
Derivative liabilities, gross amount	152	110	$ 109
Recurring \| Fair Value Inputs Level 1 And Level 2 [Member]
Other assets:
Equity securities	67	568
Liabilities:
Debt and Equity Securities, Unrealized Gain (Loss)	43	535
U.S. Treasury securities
Assets:
Securities available for sale (amortized cost of $97.0 billion and $97.6 billion and allowance for credit losses of $1 million as of both September 30, 2021 and December 31, 2020)	9,109	9,318
U.S. Treasury securities \| Recurring
Assets:
Securities available for sale (amortized cost of $97.0 billion and $97.6 billion and allowance for credit losses of $1 million as of both September 30, 2021 and December 31, 2020)	9,109	9,318
U.S. Treasury securities \| Recurring \| Level 1
Assets:
Securities available for sale (amortized cost of $97.0 billion and $97.6 billion and allowance for credit losses of $1 million as of both September 30, 2021 and December 31, 2020)	9,109	9,318
U.S. Treasury securities \| Recurring \| Level 2
Assets:
Securities available for sale (amortized cost of $97.0 billion and $97.6 billion and allowance for credit losses of $1 million as of both September 30, 2021 and December 31, 2020)	0	0
U.S. Treasury securities \| Recurring \| Level 3
Assets:
Securities available for sale (amortized cost of $97.0 billion and $97.6 billion and allowance for credit losses of $1 million as of both September 30, 2021 and December 31, 2020)	0	0
RMBS
Assets:
Securities available for sale (amortized cost of $97.0 billion and $97.6 billion and allowance for credit losses of $1 million as of both September 30, 2021 and December 31, 2020)	75,681	76,703
RMBS \| Recurring
Assets:
Securities available for sale (amortized cost of $97.0 billion and $97.6 billion and allowance for credit losses of $1 million as of both September 30, 2021 and December 31, 2020)	75,681	76,703
RMBS \| Recurring \| Level 1
Assets:
Securities available for sale (amortized cost of $97.0 billion and $97.6 billion and allowance for credit losses of $1 million as of both September 30, 2021 and December 31, 2020)	0	0
RMBS \| Recurring \| Level 2
Assets:
Securities available for sale (amortized cost of $97.0 billion and $97.6 billion and allowance for credit losses of $1 million as of both September 30, 2021 and December 31, 2020)	75,428	76,375
RMBS \| Recurring \| Level 3
Assets:
Securities available for sale (amortized cost of $97.0 billion and $97.6 billion and allowance for credit losses of $1 million as of both September 30, 2021 and December 31, 2020)	253	328
CMBS \| Recurring
Assets:
Securities available for sale (amortized cost of $97.0 billion and $97.6 billion and allowance for credit losses of $1 million as of both September 30, 2021 and December 31, 2020)	10,197	11,735
CMBS \| Recurring \| Level 1
Assets:
Securities available for sale (amortized cost of $97.0 billion and $97.6 billion and allowance for credit losses of $1 million as of both September 30, 2021 and December 31, 2020)	0	0
CMBS \| Recurring \| Level 2
Assets:
Securities available for sale (amortized cost of $97.0 billion and $97.6 billion and allowance for credit losses of $1 million as of both September 30, 2021 and December 31, 2020)	10,188	11,624
CMBS \| Recurring \| Level 3
Assets:
Securities available for sale (amortized cost of $97.0 billion and $97.6 billion and allowance for credit losses of $1 million as of both September 30, 2021 and December 31, 2020)	9	111
Other securities
Assets:
Securities available for sale (amortized cost of $97.0 billion and $97.6 billion and allowance for credit losses of $1 million as of both September 30, 2021 and December 31, 2020)	3,162	2,689
Other securities \| Recurring
Assets:
Securities available for sale (amortized cost of $97.0 billion and $97.6 billion and allowance for credit losses of $1 million as of both September 30, 2021 and December 31, 2020)	3,162	2,689
Other securities \| Recurring \| Level 1
Assets:
Securities available for sale (amortized cost of $97.0 billion and $97.6 billion and allowance for credit losses of $1 million as of both September 30, 2021 and December 31, 2020)	152	142
Other securities \| Recurring \| Level 2
Assets:
Securities available for sale (amortized cost of $97.0 billion and $97.6 billion and allowance for credit losses of $1 million as of both September 30, 2021 and December 31, 2020)	3,010	2,547
Other securities \| Recurring \| Level 3
Assets:
Securities available for sale (amortized cost of $97.0 billion and $97.6 billion and allowance for credit losses of $1 million as of both September 30, 2021 and December 31, 2020)	$ 0	$ 0