Borrowings - Summary of Long-Term Debt, Net of Debt Issuance Costs (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
Trust preferred securities	$ 247	$ 247
Other tong-term debt	390	396
Subordinated notes maturing in 2030
Debt Instrument [Line Items]
Subordinated notes	$ 143	$ 149
Interest rate (in percent)	4.125%	4.125%
3.25%, matures 2032
Debt Instrument [Line Items]
Trust preferred securities	$ 26	$ 26
Interest rate (in percent)	6.89%	3.47%
3.25%, matures 2032 \| Floating Three Month LIBOR
Debt Instrument [Line Items]
Variable rate on interest rate	3.25%
3.25%, matures 2033
Debt Instrument [Line Items]
Trust preferred securities	$ 26	$ 26
Interest rate (in percent)	5.76%	3.37%
3.25%, matures 2033 \| Floating Three Month LIBOR
Debt Instrument [Line Items]
Variable rate on interest rate	3.25%
3.25%, matures 2033
Debt Instrument [Line Items]
Trust preferred securities	$ 26	$ 26
Interest rate (in percent)	6.92%	3.47%
3.25%, matures 2033 \| Floating Three Month LIBOR
Debt Instrument [Line Items]
Variable rate on interest rate	3.25%
2.00%, matures 2035
Debt Instrument [Line Items]
Trust preferred securities	$ 26	$ 26
Interest rate (in percent)	4.51%	2.12%
2.00%, matures 2035 \| Floating Three Month LIBOR
Debt Instrument [Line Items]
Variable rate on interest rate	2.00%
2.00%, matures 2035
Debt Instrument [Line Items]
Trust preferred securities	$ 26	$ 26
Interest rate (in percent)	4.51%	2.12%
2.00%, matures 2035 \| Floating Three Month LIBOR
Debt Instrument [Line Items]
Variable rate on interest rate	2.00%
1.75%, matures 2035
Debt Instrument [Line Items]
Trust preferred securities	$ 51	$ 51
Interest rate (in percent)	5.04%	1.95%
1.75%, matures 2035 \| Floating Three Month LIBOR
Debt Instrument [Line Items]
Variable rate on interest rate	1.75%
1.50%, matures 2035
Debt Instrument [Line Items]
Trust preferred securities	$ 25	$ 25
Interest rate (in percent)	4.01%	1.62%
1.50%, matures 2035 \| Floating Three Month LIBOR
Debt Instrument [Line Items]
Variable rate on interest rate	1.50%
1.45%, matures 2037
Debt Instrument [Line Items]
Trust preferred securities	$ 25	$ 25
Interest rate (in percent)	4.74%	1.65%
1.45%, matures 2037 \| Floating Three Month LIBOR
Debt Instrument [Line Items]
Variable rate on interest rate	1.45%
2.50%, matures 2037
Debt Instrument [Line Items]
Trust preferred securities	$ 16	$ 16
Interest rate (in percent)	5.79%	2.70%
2.50%, matures 2037 \| Floating Three Month LIBOR
Debt Instrument [Line Items]
Variable rate on interest rate	2.50%

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Contractual interest rate for funds borrowed, under the debt agreement.

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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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- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of long-term debt (with maturities initially due after one year or beyond the operating cycle if longer) identified as Junior Subordinated Notes, which have a lower priority than senior instruments.

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Amount of long-term debt classified as other.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of subordinated debt (with initial maturities beyond one year or beyond the operating cycle if longer). Subordinated debt places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets.

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