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Long-Term Debt and Other Borrowed Funds (Details) - USD ($) $ in Millions | Dec. 31, 2020 | May 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
--- | --- | --- | --- | ---
Debt Instrument |  |  |  |
Stated interest rate |  | 5.25% |  |
Long-term debt | $ 98.6 |  | $ 0.0 |
Long-term debt and capital lease obligations | 112.4 |  | 13.9 |
Fiscal Year Maturities of Long-term Debt |  |  |  |
2018 | 0.1 |  |  |
2019 | 5.2 |  |  |
2020 | 0.1 |  |  |
2021 | 0.1 |  |  |
2022 | 0.1 |  |  |
Thereafter | 106.8 |  |  |
Long-term debt and capital lease obligations | 112.4 |  | $ 13.9 |
Advances from FHLB | 0.0 |  |  |
Other borrowings | 0.0 |  |  |
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net | $ 1.4 |  |  |
FIB |  |  |  |
Fiscal Year Maturities of Long-term Debt |  |  |  |
Ownership percentage in subsidiary | 99.90% |  |  |
Parent |  |  |  |
Debt Instrument |  |  |  |
Long-term debt | $ 98.6 |  |  |
Capital lease obligations | Capital Lease Obligation, 8.00% | Subsidiaries |  |  |  |
Debt Instrument |  |  |  |
Stated interest rate |  |  | 8.00% |
Capital Lease Obligations | 1.1 |  | $ 1.2 |
Notes payable | Subsidiaries |  |  |  |
Fiscal Year Maturities of Long-term Debt |  |  |  |
Long Term Debt, Acquired or Assumed | 12.6 |  |  |
Notes payable | Note Payable, 6.24% | Subsidiaries |  |  |  |
Debt Instrument |  |  |  |
Stated interest rate |  |  | 6.24% |
Notes payable | Note Payable, 1.30%, maturing March 31, 2038 [Member] | Subsidiaries |  |  |  |
Debt Instrument |  |  |  |
Long-term debt | 2.0 |  | $ 2.0 |
Notes payable | Note Payable, 1.30%, Maturing June 1, 2034 [Member] | Subsidiaries |  |  |  |
Debt Instrument |  |  |  |
Long-term debt | $ 0.6 |  | 0.6 |
Notes payable | Note Payable, Two Point Two Eight Percent | Subsidiaries |  |  |  |
Debt Instrument |  |  |  |
Stated interest rate | 2.28% |  |  |
Notes payable | Note Payable, One Percent | Subsidiaries |  |  |  |
Debt Instrument |  |  |  |
Stated interest rate | 1.00% |  |  |
Notes payable | Note Payable, 2.28% | Subsidiaries |  |  |  |
Debt Instrument |  |  |  |
Long-term debt | $ 5.0 |  | 5.0 |
Notes payable | Note Payable, 1.00% | Subsidiaries |  |  |  |
Debt Instrument |  |  |  |
Long-term debt | 5.1 |  | $ 5.1 |
Federal Home Loan Bank | Notes Payable to FHLB | Subsidiaries |  |  |  |
Fiscal Year Maturities of Long-term Debt |  |  |  |
FHLB, advances, maximum amount available | 1,697.5 |  |  |
Secured Debt |  |  |  |
Fiscal Year Maturities of Long-term Debt |  |  |  |
Line of credit facility, maximum borrowing capacity | 478.6 |  |  |
Federal Funds Purchased |  |  |  |
Fiscal Year Maturities of Long-term Debt |  |  |  |
Line of credit facility, maximum borrowing capacity | 205.0 |  |  |
Unsecured Debt [Member] |  |  |  |
Fiscal Year Maturities of Long-term Debt |  |  |  |
Line of credit facility, maximum borrowing capacity | $ 50.0 |  |  |
Subordinated term loan | Subordinated Notes Due May 2030 |  |  |  |
Fiscal Year Maturities of Long-term Debt |  |  |  |
Debt Instrument, Face Amount |  | $ 100.0 |  |
Subordinated term loan | Subordinated Term Loan, 6.81% | Parent Company |  |  |  |
Debt Instrument |  |  |  |
Stated interest rate |  |  |  | 6.81%
Minimum | Note Payable, 6.24% | Subsidiaries |  |  |  |
Debt Instrument |  |  |  |
Stated interest rate | 1.00% |  |  |
Maximum [Member] | Note Payable, 6.24% | Subsidiaries |  |  |  |
Debt Instrument |  |  |  |
Stated interest rate | 3.25% |  |  |

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