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Borrowings (Long-Term Obligations) (Details) - USD ($) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2021 | Dec. 31, 2020
Debt Instrument [Line Items] |  |
Debt Issuance Costs, Net | $ (2,629) | $ (3,459)
Long-term Debt, Fiscal Year Maturity [Abstract] |  |
2022 | 82,735 |
2023 | 125,500 |
2024 | 5,771 |
2025 | 0 |
2026 | 2,649 |
Thereafter | 977,723 |
Total long-term obligations | 1,194,378 | 1,248,163
Trust Preferred Securities | 128,100 | 128,500
Obligation guaranteed for trust subsidiaries | 14,400 |
Subordinated Debt | Fixed-to-Floating subordinated notes at 3.375% maturing March 15, 2030 |  |
Long-term Debt, Fiscal Year Maturity [Abstract] |  |
Total long-term obligations | $ 350,000 | 350,000
Debt interest rate | 3.375% |
Junior Subordinated Debt [Member] |  |
Long-term Debt, Fiscal Year Maturity [Abstract] |  |
Total long-term obligations | $ 132,500 |
Junior Subordinated Debt [Member] | Junior subordinated debenture at 3-month LIBOR plus 1.75% maturing June 30, 2036(1) |  |
Long-term Debt, Fiscal Year Maturity [Abstract] |  |
Total long-term obligations | $ 88,145 | 88,145
Junior Subordinated Debt [Member] | Junior subordinated debenture at 3-month LIBOR plus 1.75% maturing June 30, 2036(1) | Libor 3 Month Rate [Member] |  |
Debt Instrument [Line Items] |  |
Basis spread on variable rate | 1.75% |
Long-term Debt, Fiscal Year Maturity [Abstract] |  |
Description of variable rate basis | 3-month LIBOR |
Junior Subordinated Debt [Member] | Junior subordinated debenture at 3-month LIBOR plus 2.25% maturing June 15, 2034(1) |  |
Long-term Debt, Fiscal Year Maturity [Abstract] |  |
Total long-term obligations | $ 19,588 | 19,588
Junior Subordinated Debt [Member] | Junior subordinated debenture at 3-month LIBOR plus 2.25% maturing June 15, 2034(1) | Libor 3 Month Rate [Member] |  |
Debt Instrument [Line Items] |  |
Basis spread on variable rate | 2.25% |
Long-term Debt, Fiscal Year Maturity [Abstract] |  |
Description of variable rate basis | 3-month LIBOR |
Junior Subordinated Debt [Member] | Junior subordinated debenture at 3-month LIBOR plus 2.85% maturing April 7, 2034(1) |  |
Long-term Debt, Fiscal Year Maturity [Abstract] |  |
Total long-term obligations | $ 10,310 | 10,310
Junior Subordinated Debt [Member] | Junior subordinated debenture at 3-month LIBOR plus 2.85% maturing April 7, 2034(1) | Libor 3 Month Rate [Member] |  |
Debt Instrument [Line Items] |  |
Basis spread on variable rate | 2.85% |
Long-term Debt, Fiscal Year Maturity [Abstract] |  |
Description of variable rate basis | 3-month LIBOR |
Junior Subordinated Debt [Member] | Junior subordinated debentures at 3-month LIBOR plus 2.80% maturing March 30, 2034(1) |  |
Long-term Debt, Fiscal Year Maturity [Abstract] |  |
Total long-term obligations | $ 14,433 | 14,433
Junior Subordinated Debt [Member] | Junior subordinated debentures at 3-month LIBOR plus 2.80% maturing March 30, 2034(1) | Libor 3 Month Rate [Member] |  |
Debt Instrument [Line Items] |  |
Basis spread on variable rate | 2.80% |
Long-term Debt, Fiscal Year Maturity [Abstract] |  |
Description of variable rate basis | 3-month LIBOR |
Junior Subordinated Debt [Member] | Junior subordinated debentures at 7.00% maturing December 31, 2026(2) |  |
Long-term Debt, Fiscal Year Maturity [Abstract] |  |
Total long-term obligations | $ 0 | 20,000
Junior Subordinated Debt [Member] | Junior subordinated debentures at 7.00% maturing December 31, 2026(2) | Libor 3 Month Rate [Member] |  |
Long-term Debt, Fiscal Year Maturity [Abstract] |  |
Debt interest rate | 7.00% |
Junior Subordinated Debt [Member] | Junior subordinated debentures at 6.50% maturing October 1, 2025(3) |  |
Long-term Debt, Fiscal Year Maturity [Abstract] |  |
Total long-term obligations | $ 0 | 7,500
Junior Subordinated Debt [Member] | Junior subordinated debentures at 6.50% maturing October 1, 2025(3) | Libor 3 Month Rate [Member] |  |
Long-term Debt, Fiscal Year Maturity [Abstract] |  |
Debt interest rate | 6.50% |
Notes payable to FHLB of Atlanta | Notes payable to FHLBs of Atlanta and Chicago with rates ranging from 0.75% to 2.99% and maturing through March 2032 |  |
Long-term Debt, Fiscal Year Maturity [Abstract] |  |
Total long-term obligations | $ 644,659 | 655,175
Notes payable to FHLB of Atlanta | Notes payable to FHLBs of Atlanta and Chicago with rates ranging from 0.75% to 2.99% and maturing through March 2032 | Minimum |  |
Long-term Debt, Fiscal Year Maturity [Abstract] |  |
Debt interest rate | 0.75% |
Notes payable to FHLB of Atlanta | Notes payable to FHLBs of Atlanta and Chicago with rates ranging from 0.75% to 2.99% and maturing through March 2032 | Maximum |  |
Long-term Debt, Fiscal Year Maturity [Abstract] |  |
Debt interest rate | 2.99% |
Unsecured Term Loan [Member] | Unsecured term loan at 1-month LIBOR plus 1.10% maturing September 5, 2022 |  |
Long-term Debt, Fiscal Year Maturity [Abstract] |  |
Total long-term obligations | $ 67,825 | 82,125
Unsecured Term Loan [Member] | Unsecured term loan at 1-month LIBOR plus 1.10% maturing September 5, 2022 | Libor 1 Month Rate [Member] |  |
Debt Instrument [Line Items] |  |
Basis spread on variable rate | 1.10% |
Long-term Debt, Fiscal Year Maturity [Abstract] |  |
Description of variable rate basis | 1-month LIBOR |
Capital Lease Obligations [Member] |  |
Long-term Debt, Fiscal Year Maturity [Abstract] |  |
Total long-term obligations | $ 4,311 | 6,308
Unamortized Purchase Accounting Adjustments [Member] |  |
Long-term Debt, Fiscal Year Maturity [Abstract] |  |
Total long-term obligations | (2,283) | (1,999)
Other Long Term Debt [Member] |  |
Long-term Debt, Fiscal Year Maturity [Abstract] |  |
Total long-term obligations | $ 19 | $ 37

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