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Long-term borrowings (Details Textual) - USD ($) |  |  |  | 1 Months Ended |  |
--- | --- | --- | --- | --- | --- | ---
Nov. 01, 2021 | Jan. 07, 2020 | Dec. 31, 2015 | Nov. 30, 2021 | Mar. 31, 2022 | Dec. 31, 2021
Debt Instrument [Line Items] |  |  |  |  |  |
Long-rem advances from FHLB |  |  |  |  | $ 0 | $ 0
Residential mortgage, commercial real estate, and multi-family loans |  |  |  |  | 1,300,000,000 | $ 1,200,000,000
Additional borrowing limit |  |  |  |  | $ 679,800,000 |
Cortland Bank |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Business acquisition, date of merger agreement | Nov. 01, 2021 |  |  |  |  |
Long-term borrowings | $ 4,262,000 |  |  |  |  |
Subordinated Notes |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Aggregate principal amount |  |  |  | $ 75,000,000.0 |  |
Maturity date |  |  |  | Dec. 15, 2031 |  |
Fixed rate |  |  |  | 3.125% |  |
Notes maturity term |  |  |  | 5 years |  |
Basis spread on variable rate |  |  |  | 220.00% |  |
Net proceeds from sale |  |  |  | $ 73,800,000 |  |
Junior Subordinated Debt Securities | Cortland Bank |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Maturity date | Sep. 15, 2037 |  |  |  |  |
Business acquisition, date of merger agreement | Nov. 01, 2021 |  |  |  |  |
Long-term borrowings | $ 4,300,000 |  |  |  |  |
Interest rate, effective percentage |  |  |  |  | 2.28% | 1.65%
Junior Subordinated Debt Securities | Cortland Bank | 3-month LIBOR Rate |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Basis spread on variable rate | 1.45% |  |  |  |  |
Junior Subordinated Debt Securities | Maple Leaf |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Maturity date |  | Dec. 15, 2036 |  |  |  |
Business acquisition, date of merger agreement |  | Jan. 07, 2020 |  |  |  |
Interest rate, effective percentage |  |  |  |  | 2.63% | 1.90%
Junior Subordinated Debt Securities | Maple Leaf | 3-month LIBOR Rate |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Basis spread on variable rate |  | 1.70% |  |  |  |
Junior Subordinated Debt Securities | National Bancshares Corporation |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Maturity date |  |  | Jun. 15, 2035 |  |  |
Interest rate, effective percentage |  |  |  |  | 2.53% | 2.00%
Junior Subordinated Debt Securities | National Bancshares Corporation | 3-month LIBOR Rate |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Basis spread on variable rate |  |  | 1.80% |  |  |

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- Definition Amount of long-term debt due after one year or the normal operating cycle, if longer, assumed at the acquisition date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=123413009&loc=d3e4845-128472 + Details
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