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v3.23.3

Borrowings - Additional information (Details) $ in Thousands |  |  | 1 Months Ended | 3 Months Ended | 9 Months Ended |  |
--- | --- | --- | --- | --- | --- | --- | ---
Feb. 24, 2023 USD ($) | Feb. 24, 2020 USD ($) | Dec. 31, 2016 | Sep. 30, 2023 USD ($) item | Jun. 30, 2021 USD ($) | Sep. 30, 2023 USD ($) item | Sep. 30, 2022 USD ($) | Jun. 30, 2023 USD ($) | Dec. 31, 2022 USD ($)
Borrowings |  |  |  |  |  |  |  |  |
Securities available-for-sale, at fair value |  |  |  | $ 1,229,618 |  | $ 1,229,618 |  |  | $ 1,539,359
Number of customers having secured balances exceeding specified percentage of stockholders equity | item |  |  |  | 0 |  | 0 |  |  |
Threshold percentage of stockholders' equity |  |  |  |  |  | 10.00% |  |  |
Borrowings at FHLBC as percentage of total assets |  |  |  | 35.00% |  | 35.00% |  |  |
Borrowings at FHLBC as percentage of book value of certain mortgage loans |  |  |  | 60.00% |  | 60.00% |  |  |
FHLBC stock |  |  |  | $ 20,900 |  | $ 20,900 |  |  | 5,600
Federal Home Loan Bank Chicago ("FHLBC") and Federal Reserve Bank Chicago ("FRBC") stock |  |  |  | 35,830 |  | 35,830 |  |  | 20,530
Proceeds from term note |  | $ 30,000 |  |  |  |  |  |  |
Repayment of term note |  |  |  |  |  | 9,000 | $ 3,000 |  |
Senior notes |  |  |  |  |  |  |  |  | 44,585
Basis points added to reference rate (as a percent) |  | 175.00% |  |  |  |  |  |  |
Total borrowings |  |  |  | 546,028 |  | 546,028 |  |  | 260,811
Asset Pledged as Collateral with Right | Securities sold under repurchase agreements |  |  |  |  |  |  |  |  |
Borrowings |  |  |  |  |  |  |  |  |
Securities available-for-sale, at fair value |  |  |  | 43,800 |  | 43,800 |  |  | 71,400
Three Months Secured Overnight Financing Rate |  |  |  |  |  |  |  |  |
Borrowings |  |  |  |  |  |  |  |  |
Basis points added to reference rate (as a percent) |  |  |  |  | 273.00% |  |  |  |
Securities sold under repurchase agreements |  |  |  |  |  |  |  |  |
Borrowings |  |  |  |  |  |  |  |  |
Total borrowings |  |  |  | 25,894 |  | 25,894 |  |  | 32,156
Securities sold under repurchase agreements | Asset Pledged as Collateral with Right | Securities sold under repurchase agreements |  |  |  |  |  |  |  |  |
Borrowings |  |  |  |  |  |  |  |  |
Investment securities pledged with financial institutions, dollars |  |  |  | $ 25,900 |  | $ 25,900 |  |  | 32,200
Federal Home Loan Bank Advances |  |  |  |  |  |  |  |  |
Borrowings |  |  |  |  |  |  |  |  |
Borrowings at FHLBC as percentage of book value of certain mortgage loans |  |  |  | 60.00% |  | 60.00% |  |  |
FHLBC advance amount |  |  |  | $ 435,000 |  | $ 435,000 |  |  | 90,000
FHLBC stock |  |  |  | 20,900 |  | 20,900 |  |  |
Principal balance of loans collateralized |  |  |  | 1,470,000 |  | 1,470,000 |  |  |
Combined collateral value |  |  |  | 1,020,000 |  | 1,020,000 |  |  |
Amount available for additional borrowings |  |  |  | 581,700 |  | 581,700 |  |  |
Subordinated debentures |  |  |  |  |  |  |  |  |
Borrowings |  |  |  |  |  |  |  |  |
Total borrowings |  |  |  | 59,361 |  | 59,361 |  |  | 59,297
Notes Payable to Banks [Member] |  |  |  |  |  |  |  |  |
Borrowings |  |  |  |  |  |  |  |  |
Total borrowings |  |  |  |  |  |  |  |  | 9,000
Junior subordinated debentures |  |  |  |  |  |  |  |  |
Borrowings |  |  |  |  |  |  |  |  |
Total borrowings |  |  |  | $ 25,773 |  | $ 25,773 |  |  | $ 25,773
Senior Notes [Member] |  |  |  |  |  |  |  |  |
Borrowings |  |  |  |  |  |  |  |  |
Interest rate (as a percent) |  |  | 5.75% |  |  |  |  |  |
Debt Instrument, Term |  |  | 10 years |  |  |  |  |  |
Interest rate term |  |  | 5 years |  |  |  |  |  |
Effective interest rate |  |  |  | 9.39% |  | 9.39% |  |  | 8.62%
Total borrowings |  |  |  |  |  |  |  |  | $ 44,585
Debt instrument redemption price, percentage |  |  |  | 12.85% |  | 100.00% |  |  |
Debt redeemed amount |  |  |  |  |  |  |  | $ 45,000 |
Debt issuance costs |  |  |  | $ 362 |  |  |  |  |
Senior Notes [Member] | Debt Instrument Variable Rate Base LIBOR [Member] |  |  |  |  |  |  |  |  |
Borrowings |  |  |  |  |  |  |  |  |
Basis points added to reference rate (as a percent) |  |  | 3.85% |  |  |  |  |  |
Term Debt |  |  |  |  |  |  |  |  |
Borrowings |  |  |  |  |  |  |  |  |
Proceeds from term note |  | $ 20,000 |  |  |  |  |  |  |
Repayment of term note | $ 9,000 |  |  |  |  |  |  |  |
Debt term |  | 3 years |  |  |  |  |  |  |
Subordinated Notes Due 2031 |  |  |  |  |  |  |  |  |
Borrowings |  |  |  |  |  |  |  |  |
Interest rate (as a percent) |  |  |  |  | 3.50% |  |  |  |
Outstanding, net of deferred issuance costs |  |  |  | $ 59,400 |  | $ 59,400 |  |  | $ 59,300
Face amount |  |  |  |  | $ 60,000 |  |  |  |

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