Loans and Allowance for Credit Losses - Narrative (Details) $ in Millions	12 Months Ended
Dec. 31, 2021 USD ($) loan loanSegment	Dec. 31, 2020 USD ($) loan	Dec. 31, 2019 USD ($)
Financing Receivable, Credit Quality Indicator [Line Items]
Number of loans and leases segments \| loanSegment	2
Loans and leases pledged as collateral	$ 10,800	$ 8,070
Number of loans on non-accrual status \| loan	0	0
Sale of loans	$ 172	$ 324	$ 131
Loans remained unsettled	8
Provision (reversal) for credit loss	$ 33
Loans modified in troubled debt restructurings \| loan	0	0
Loans no longer meeting similar risk of collective pool \| loan	9
Loans no longer meeting similar risk of collective pool, amount	$ 232
Allowance for credit loss	$ 87	$ 122
Investment grade loans	84.00%
Speculative grade loans	15.00%
Speculative senior secured loans with BB or B rating	94.00%
Leveraged Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Sale of loans	$ 181
Provision (reversal) for credit loss	(2)
Commercial and Financial
Financing Receivable, Credit Quality Indicator [Line Items]
Allowance for credit loss	11
Collateralized Loan Obligations
Financing Receivable, Credit Quality Indicator [Line Items]
Payments to acquire loans receivable	$ 2,913

Financing Receivable, Recorded Investment, Nonaccrual Status, Number of Loans

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- Definition

Investment Grade Loans

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Loans And Leases Receivable, Number Of Loans And Leases Segments

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Loans No Longer Meeting Similar Risk of Collective Pool

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Number of Loans, No Longer Met Similar Risk

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Speculative Grade Loans

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No definition available.

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- Definition

Speculative Senior Secured Loans, with BB or B Rating

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No definition available.

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- Definition

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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- Definition

Number of financing receivables that have been modified by troubled debt restructurings.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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Amount of gain (loss) on sale of financing receivable.

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- Definition

Carrying amount as of the balance sheet date of loans that have been pledged as collateral for borrowings. If the secured party has the right by contract or custom to sell or re-pledge the collateral, then the debtor reclassifies that asset and report that asset in its statement of financial position separately from other assets not so encumbered.

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The cash outflow for the purchase of loan receivable arising from the financing of goods and services.

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The cash inflow associated with the sale of loans receivables arising from the financing of goods and services.

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Amount of credit loss expense (reversal of expense) for financing receivable.

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