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Note 4 - Premises and Equipment, Net (Details Textual) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Depreciation, Total | $ 5.8 | $ 5.2 | $ 3.9
Operating Lease, Weighted Average Remaining Lease Term (Year) | 2 years 9 months 18 days |  |
Operating Lease, Weighted Average Discount Rate, Percent | 4.71% |  |
Operating Lease, Expense | $ 0.6 | 0.6 | $ 0.5
Lessee, Operating Lease, Liability, to be Paid, Total | 3.6 | 3.4 |
Lessee, Operating Lease, Liability, to be Paid, Year One | 0.8 | 0.6 |
Lessee, Operating Lease, Liability, to be Paid, Year Two and Year Three | 1.4 | 1.2 |
Lessee, Operating Lease, Liability, to be Paid, Year Four and Year Five | 0.3 | 0.5 |
Lessee, Operating Lease, Liability, to be Paid, after Year Five | 1.1 | 1.1 |
Premises and Equipment, Net [Member] |  |  |
Operating Lease, Right-of-Use Asset | 2.9 | 1.1 |
Other Liabilities [Member] |  |  |
Operating Lease, Liability, Total | $ 2.8 | $ 0.9 |
Minimum [Member] |  |  |
Lessee, Operating Lease, Renewal Term (Year) | 3 years |  |
Maximum [Member] |  |  |
Lessee, Operating Lease, Renewal Term (Year) | 5 years |  |

X
- Definition Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in fourth and fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References No definition available. + Details
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X
- Definition Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in second and third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References No definition available. + Details
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- Definition The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3602-108585 + Details
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- Definition Amount of lessee's undiscounted obligation for lease payment for operating lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=123408670&loc=SL77918701-209980 + Details
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- Definition Amount of lessee's undiscounted obligation for lease payment for operating lease due after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=123408670&loc=SL77918701-209980 + Details
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- Definition Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=123408670&loc=SL77918701-209980 + Details
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- Definition Term of lessee's operating lease renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=123408670&loc=SL77918673-209980 + Details
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- Definition Amount of operating lease expense. Excludes sublease income. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 45 -Paragraph 4 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=123391704&loc=SL77918638-209977 + Details
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- Definition Present value of lessee's discounted obligation for lease payments from operating lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 45 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=123391704&loc=SL77918627-209977 + Details
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- Definition Amount of lessee's right to use underlying asset under operating lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 45 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=123391704&loc=SL77918627-209977 + Details
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