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Subordinated Notes and Junior Subordinated Debentures - Junior Subordinated Debentures by Issuance (Details) - USD ($) $ in Thousands | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2021 | Dec. 31, 2020
Shares Subject To Mandatory Redemption By Settlement Terms [Line Items] |  |
Total liability, at par | $ 45,000 | $ 45,000
Total liability, at carrying value | 36,796 | 36,451
Metropolitan Statutory Trust 1 |  |
Shares Subject To Mandatory Redemption By Settlement Terms [Line Items] |  |
Total liability, at par | 35,000 | 35,000
First Evanston Bancorp Trust I |  |
Shares Subject To Mandatory Redemption By Settlement Terms [Line Items] |  |
Total liability, at par | 10,000 | 10,000
Junior Subordinated Debentures |  |
Shares Subject To Mandatory Redemption By Settlement Terms [Line Items] |  |
Discount | $ (8,204) | $ (8,549)
Junior Subordinated Debentures | Metropolitan Statutory Trust 1 |  |
Shares Subject To Mandatory Redemption By Settlement Terms [Line Items] |  |
Stated Maturity | Mar. 17, 2034 |
Contractual Rate | 2.91% | 3.02%
Junior Subordinated Debentures | Metropolitan Statutory Trust 1 | Three-month LIBOR |  |
Shares Subject To Mandatory Redemption By Settlement Terms [Line Items] |  |
Interest Rate Spread, Description | Three-monthLIBOR + 2.79% |
Interest Rate Spread | 2.79% | 2.79%
Junior Subordinated Debentures | First Evanston Bancorp Trust I |  |
Shares Subject To Mandatory Redemption By Settlement Terms [Line Items] |  |
Stated Maturity | Mar. 15, 2035 |
Contractual Rate | 1.90% | 2.00%
Junior Subordinated Debentures | First Evanston Bancorp Trust I | Three-month LIBOR |  |
Shares Subject To Mandatory Redemption By Settlement Terms [Line Items] |  |
Interest Rate Spread, Description | Three-monthLIBOR + 1.78% |
Interest Rate Spread | 1.78% | 1.78%

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- Definition Junior subordinated debenture owed to unconsolidated subsidiary trust, including unamortized discount. + References No definition available. + Details
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- Definition Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 6 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=120520924&loc=SL6036836-161870 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=119993939&loc=d3e28551-108399 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
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- Definition Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(2)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bbb)(2) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
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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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