Borrowings and Subordinated Debentures (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
Borrowings	$ 1,764,030	$ 0
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate	5.36%	0.00%
Other Borrowings, Fair Value Disclosure	$ 132,030	$ 0
Credit-Link Notes
Debt Instrument [Line Items]
Long-term Debt, Percentage Bearing Variable Interest, Percentage Rate	14.56%	0.00%
Long-term Debt, Percentage Bearing Variable Interest, Amount	$ 132,800	$ 0
Other Borrowings, Fair Value Disclosure	$ 132,030	$ 0
American Financial Exchange
Debt Instrument [Line Items]
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate	4.68%	0.00%
Line of Credit Facility, Amount Outstanding	$ 250,000	$ 0
Federal Home Loan Bank of San Francisco
Debt Instrument [Line Items]
Line of Credit, Current	$ 1,270,000	$ 0
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate	4.62%	0.00%
Federal Home Loan Bank of San Francisco \| Secured Debt
Debt Instrument [Line Items]
Line of Credit, Current	$ 1,270,000	$ 0
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate	4.62%	0.00%
Federal Home Loan Bank of San Francisco \| Unsecured Debt
Debt Instrument [Line Items]
Line of Credit, Current	$ 112,000	$ 0
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate	4.37%	0.00%
Federal Home Loan Bank of San Francisco \| Term Advance
Debt Instrument [Line Items]
Line of Credit, Current	$ 250,000	$ 0
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate	4.64%	0.00%

Other Borrowings, Fair Value Disclosure

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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

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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The carrying value as of the balance sheet date of the current portion of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a set, unchanging rate.

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The portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a rate subject to change from time to time.

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