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v3.20.4

Junior Subordinated Debentures - Issuance (Details) |  |  |  | 1 Months Ended | 6 Months Ended | 7 Months Ended | 12 Months Ended |
--- | --- | --- | --- | --- | --- | --- | --- | ---
Dec. 31, 2020 USD ($) | Mar. 02, 2020 USD ($) $ / shares | Feb. 24, 2020 USD ($) | Apr. 30, 2007 USD ($) | Jun. 15, 2017 | Dec. 31, 2017 | Dec. 31, 2020 USD ($) | Dec. 31, 2019 USD ($) item | Dec. 31, 2018 USD ($) | Jun. 16, 2017
Junior subordinated debentures |  |  |  |  |  |  |  |  |  |
Cash distribution rate of trust preferred securities (as a percent) |  |  | 7.80% |  |  |  |  |  |  |
Junior subordinated debentures | $ 25,773,000 |  |  |  |  |  | $ 25,773,000 | $ 57,734,000 |  |
Junior Subordinated Debentures issuance cost |  |  |  |  |  |  |  | 1,000 | $ 644,000 |
Cash disbursed for redemption |  | $ 33,000,000.0 |  |  |  |  |  |  |  |
Redemption price per share | $ / shares |  | $ 10.13 |  |  |  |  |  |  |  |
Proceeds from term note | 20,000,000.0 |  | $ 20,000,000 |  |  |  |  |  |  |
Unamortized debt issuance costs |  | $ 635,000 |  |  |  |  | $ 643,000 | $ 48,000 | $ 47,000 |
Old Second Capital Trust II [Member] |  |  |  |  |  |  |  |  |  |
Junior subordinated debentures |  |  |  |  |  |  |  |  |  |
Proceeds from sale of cumulative trust preferred securities |  |  |  | $ 25,000,000.0 |  |  |  |  |  |
Maturity Period |  |  |  |  |  |  |  | 30 years |  |
Cash distribution fixed rate of trust preferred securities (as a percent) |  |  |  |  | 6.77% |  |  |  |  |
Basis points added to cash distribution floating rate base (as a percent) |  |  |  |  |  | 1.50% |  |  |  |
Cash distribution, floating rate base |  |  |  |  |  |  |  |  | three-month LIBOR |
Term note |  |  |  |  |  |  |  |  |  |
Junior subordinated debentures |  |  |  |  |  |  |  |  |  |
Proceeds from term note | $ 17,000,000.0 |  | $ 20,000,000.0 |  |  |  |  |  |  |
Junior Subordinated Debt |  |  |  |  |  |  |  |  |  |
Junior subordinated debentures |  |  |  |  |  |  |  |  |  |
Interest Payment Deferment Period | item |  |  |  |  |  |  |  | 20 |  |
Junior Subordinated Debt | Old Second Capital Trust I |  |  |  |  |  |  |  |  |  |
Junior subordinated debentures |  |  |  |  |  |  |  |  |  |
Cash distribution rate of trust preferred securities (as a percent) |  | 7.80% |  |  |  |  |  |  |  |
Junior subordinated debentures |  | $ 32,600,000 |  |  |  |  |  |  |  |
Amortization period |  | 30 years |  |  |  |  |  |  |  |
Junior Subordinated Debt | Old Second Capital Trust II [Member] |  |  |  |  |  |  |  |  |  |
Junior subordinated debentures |  |  |  |  |  |  |  |  |  |
Interest rate (as a percent) | 4.40% |  |  |  |  |  | 4.40% | 4.40% |  | 2.80%
Junior subordinated debentures |  |  |  |  |  |  |  | $ 25,800,000 |  |
7.8% subordinated debentures |  |  |  |  |  |  |  |  |  |
Junior subordinated debentures |  |  |  |  |  |  |  |  |  |
Interest rate (as a percent) |  | 7.80% |  |  |  |  |  |  |  |

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- Definition Including the current and noncurrent portions, the carrying value of junior subordinated long-term debt owed to unconsolidated subsidiary trusts as of the balance sheet date. Such debt places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets and was initially scheduled to be repaid after one year or beyond the normal operating cycle if longer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.16) -URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.16) -URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878 + Details
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- Definition The cash outflow to reacquire preferred stocks issued by a business trust or other special purpose entity, mainly established by a bank holding entity, to third party investors. The trust's assets are deeply subordinated debentures of the bank holding entity. Most trust preferred securities are subject to a mandatory redemption upon the repayment of the debentures. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3291-108585 + Details
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