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v3.20.1

Borrowings - Additional information (Details) |  |  | 3 Months Ended |  |
--- | --- | --- | --- | --- | ---
Mar. 02, 2020 USD ($) | Feb. 24, 2020 USD ($) | Mar. 31, 2020 USD ($) item | Dec. 31, 2016 | Dec. 31, 2019 USD ($) | Apr. 20, 2018 USD ($)
Borrowings |  |  |  |  |  |
Interest rate (as a percent) |  |  |  | 5.75% |  |
Bank owned FHLBC stock |  |  | $ 3,700,000 |  |  |
Senior notes |  |  | 44,297,000 |  | $ 44,270,000 |
Debt Instrument, Term |  |  |  | 10 years |  |
Interest rate term |  |  |  | 5 years |  |
Total borrowings |  |  | $ 154,290,000 |  | 205,870,000 |
GCFC/ABC Bank |  |  |  |  |  |
Borrowings |  |  |  |  |  |
Interest rate (as a percent) |  |  | 2.83% |  |  |
FHLBC advance amount |  |  | $ 6,000,000 |  |  |
Subordinated Debt. |  |  |  |  |  | $ 6,600,000
Debt assumed |  |  | 23,400,000 |  |  |
Debt Instrument, Variable Rate Base LIBOR [Member] |  |  |  |  |  |
Borrowings |  |  |  |  |  |
Basis points added to reference rate (as a percent) |  |  |  | 385.00% |  |
Securities Sold under Agreements to Repurchase [Member] |  |  |  |  |  |
Borrowings |  |  |  |  |  |
Carrying amount of securities secured |  |  | 51,200,000 |  | 48,700,000 |
Fair value of the pledged collateral |  |  | $ 71,200,000 |  | 70,700,000 |
Number of customers having secured balances exceeding specified percentage of stockholders equity | item |  |  | 0 |  |  |
Total borrowings |  |  | $ 51,236,000 |  | 48,693,000 |
Securities Sold under Agreements to Repurchase [Member] | Minimum [Member] |  |  |  |  |  |
Borrowings |  |  |  |  |  |
Threshold percentage of stockholders' equity |  |  | 10.00% |  |  |
Federal Home Loan Bank Advances [Member] |  |  |  |  |  |
Borrowings |  |  |  |  |  |
Borrowings at FHLBC as percentage of total assets |  |  | 35.00% |  |  |
Borrowings at FHLBC as percentage of book value of certain mortgage loans |  |  | 60.00% |  |  |
FHLBC advance amount |  |  | $ 6,400,000 |  | 48,500,000 |
Bank owned FHLBC stock |  |  | 3,700,000 |  |  |
Fair value of securities collateralized |  |  | 51,000,000 |  |  |
Principal balance of loans collateralized |  |  | 568,300,000 |  |  |
Combined collateral value |  |  | 481,600,000 |  |  |
Amount available for additional borrowings |  |  | 344,300,000 |  |  |
Total borrowings |  |  | 6,375,000 |  | 48,500,000 |
FHLB advances at 1.76% to 2.23% |  |  |  |  |  |
Borrowings |  |  |  |  |  |
FHLBC advance amount |  |  | $ 6,400,000 |  |  |
FHLB advances at 1.76% to 2.23% | Minimum [Member] |  |  |  |  |  |
Borrowings |  |  |  |  |  |
Interest rate (as a percent) |  |  | 2.03% |  |  |
FHLB advances at 1.76% to 2.23% | Maximum [Member] |  |  |  |  |  |
Borrowings |  |  |  |  |  |
Interest rate (as a percent) |  |  | 2.23% |  |  |
Notes Payable to Banks [Member] |  |  |  |  |  |
Borrowings |  |  |  |  |  |
Total borrowings |  |  | $ 26,609,000 |  | 6,673,000 |
Credit Facility [Member] |  |  |  |  |  |
Borrowings |  |  |  |  |  |
Proceeds from term note |  | $ 20,000,000 |  |  |  |
Debt Instrument, Term |  | 360 days |  |  |  |
Junior Subordinated Debt |  |  |  |  |  |
Borrowings |  |  |  |  |  |
Total borrowings |  |  | 25,773,000 |  | 57,734,000 |
Senior Notes. |  |  |  |  |  |
Borrowings |  |  |  |  |  |
Senior notes |  |  | 44,297,000 |  | 44,270,000 |
Debt issuance costs |  |  | $ 703,000 |  | $ 730,000 |
Amortization period for deferred financing costs |  |  | 10 years |  |  |
Term note |  |  |  |  |  |
Borrowings |  |  |  |  |  |
Proceeds from term note | $ 20,000,000 | $ 20,000,000 |  |  |  |
Debt term |  | 3 years |  |  |  |
Term note | Debt Instrument, Variable Rate Base LIBOR [Member] |  |  |  |  |  |
Borrowings |  |  |  |  |  |
Basis points added to reference rate (as a percent) |  | 175.00% |  |  |  |
Old Second Capital Trust I | Junior Subordinated Debt |  |  |  |  |  |
Borrowings |  |  |  |  |  |
Cash distribution rate of trust preferred securities (as a percent) |  | 7.80% |  |  |  |

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