Borrowings (Long-Term Debt) (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
Notes and subordinated debt	$ 1,059,778	$ 566,131
Debt issuance cost on senior fixed-rate notes	(1,824)	(2,226)
Long-term debt	$ 1,073,128	$ 562,931
Long term debt, variable interest rate, percentage	7.69%	3.17%
Hedged Liability, Fair Value Hedge, Cumulative Increase (Decrease)		$ 38,811
Subordinated Debt
Debt Instrument [Line Items]
Debt Instrument, Unamortized Premium	$ 15,930	0
London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Interest rate spread of LIBOR plus (as a percent)	2.95%
Junior Subordinated Debt [Member]
Debt Instrument [Line Items]
Notes and subordinated debt	$ 77,320	77,320
Long-term Debt [Member]
Debt Instrument [Line Items]
Discount on senior fixed-rate notes	(756)	(974)
Hedged Liability, Fair Value Hedge, Cumulative Increase (Decrease)	33,500	38,800
Subordinated Notes Due 2029 \| Subordinated Debt
Debt Instrument [Line Items]
Long-Term Debt, Gross	274,000	0
Subordinated Notes Due 2030 \| Subordinated Debt
Debt Instrument [Line Items]
Long-Term Debt, Gross	225,000	0
Debt Instrument, Redemption, Period One [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Notes and subordinated debt	$ 150,000	150,000
Debt instrument, stated interest rate, percentage	4.375%
Debt Instrument, Redemption, Period Two \| Senior Notes [Member]
Debt Instrument [Line Items]
Notes and subordinated debt	$ 333,458	$ 338,811
Debt instrument, stated interest rate, percentage	4.10%

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Face (par) amount of debt instrument at time of issuance.

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

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Amount, after accumulated amortization, of debt discount.

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Amount, after accumulated amortization, of debt premium.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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The percentage points added to the reference rate to compute the variable rate on the interest rate derivative.

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Amount of cumulative increase (decrease) in fair value of hedged liability in fair value hedge, attributable to hedged risk.

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Amount, excluding unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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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 rate subject to change from time to time.

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