Borrowings (Long Term Debt) (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
Notes and subordinated debt	$ 1,063,793	$ 566,131
Debt issuance cost on senior fixed-rates	(2,125)	(2,226)
Long-term debt	1,078,274	562,931
Hedge basis adjustment	$ 337,473	$ 338,811
Variable interest rate	3.87%	3.17%
London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Basis spread on variable rate	2.95%
Senior Notes
Debt Instrument [Line Items]
Discount on senior fixed-rate notes	$ (920)	$ (974)
Senior Notes \| Senior Notes Due 2024
Debt Instrument [Line Items]
Senior notes, interest rate (as a percent)	4.375%
Notes and subordinated debt	$ 150,000	150,000
Senior Notes \| Senior Notes Due 2029
Debt Instrument [Line Items]
Senior notes, interest rate (as a percent)	4.10%
Notes and subordinated debt	$ 337,473	338,811
Hedge basis adjustment	37,500	38,800
Subordinated Debt
Debt Instrument [Line Items]
Premium on subordinated fixed-to-floating rate notes	$ 17,526	0
Subordinated Debt \| Subordinated Notes Due 2029
Debt Instrument [Line Items]
Senior notes, interest rate (as a percent)	4.00%
Notes and subordinated debt	$ 274,000	0
Subordinated Debt \| Subordinated Notes Due 2030
Debt Instrument [Line Items]
Senior notes, interest rate (as a percent)	3.875%
Notes and subordinated debt	$ 225,000	0
Junior subordinated debt
Debt Instrument [Line Items]
Notes and subordinated debt	77,320	77,320
Long-term Debt
Debt Instrument [Line Items]
Hedge basis adjustment	$ 37,473	$ 38,811

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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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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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, 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 rate subject to change from time to time.

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