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Note 8 - Subsequent Events (Details Textual) - USD ($) $ in Millions |  | 3 Months Ended | 12 Months Ended
--- | --- | --- | ---
Apr. 21, 2022 | Mar. 31, 2022 | Dec. 31, 2021
Federal Fund Rate, Increase Rate |  | 0.25% |
OCI, Debt Securities, Available-for-Sale, Unrealized Holding Gain (Loss), before Adjustment and Tax |  | $ 42.8 | $ 3.3
Interest Rate Cap [Member] | Subsequent Event [Member] |  |  |
Derivative, Notional Amount | $ 200.0 |  |
Derivative, Term of Contract (Year) | 8 years |  |
Interest Rate Cap [Member] | Subsequent Event [Member] | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate [Member] |  |  |
Derivative, Cap Interest Strike Price | 2.68% |  |
Pay-fixed Interest Rate Swap [Member] | Subsequent Event [Member] |  |  |
Derivative, Notional Amount | $ 200.0 |  |
Derivative, Term of Contract (Year) | 8 years |  |
Pay-fixed Interest Rate Swap [Member] | Subsequent Event [Member] | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate [Member] |  |  |
Derivative, Forward Swap, Coupon Rate | 2.75% |  |
Receive-fixed Interest Rate Swap [Member] | Subsequent Event [Member] |  |  |
Derivative, Notional Amount | $ 200.0 |  |
Derivative, Forward Swap, Coupon Rate | 2.41% |  |

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- Definition Amount, before tax and adjustment, of unrealized holding gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Excludes unrealized gain (loss) on investment in debt security measured at amortized cost (held-to-maturity) from transfer to available-for-sale. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (e) -URI https://asc.fasb.org/extlink&oid=126968391&loc=SL7669646-108580 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 11 -URI https://asc.fasb.org/extlink&oid=126968391&loc=d3e637-108580 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (d) -URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27357-111563 + Details
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