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The number of operating branches.

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Investments in SBA loans.

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Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, without jurisdictional netting.

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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Amount of Federal Home Loan Bank (FHLB) and Federal Reserve Bank stock.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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Amount of credit loss expense (reversal of expense) for financing receivable.

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Amount of unrecognized tax benefits.

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Note 1 - Nature of Operations and Summary of Significant Accounting Policies (Details Textual)		12 Months Ended
	May 10, 2019 USD ($)	Dec. 31, 2020 USD ($) $ / shares	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Federal Home Loan Bank Stock and Federal Reserve Bank Stock, Total		$ 7,300,000	$ 7,400,000
Impairment of Investment in Federal Home Loan Bank Stock and Federal Reserve Bank Stock		0	0
SBA Loan Funds		4,500,000	4,500,000
Financing Receivable, Credit Loss, Expense (Reversal)		2,170,000	4,971,000	$ 1,303,000
Deferred Tax Assets, Valuation Allowance, Total		1,937,000
Deferred Tax Assets, Net, Total		11,496,000	11,133,000
Unrecognized Tax Benefits, Ending Balance		0	1,220,000	1,132,000
Goodwill, Purchase Accounting Adjustments			$ (621,000)
Prime Bank [Member]
Goodwill, Purchase Accounting Adjustments	$ (621,000)
Prime Bank [Member] \| Project Expenses [Member]
Goodwill, Purchase Accounting Adjustments		$ 556,000
Vesting Period One [Member] \| Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)		3 years
Vesting Period Two [Member] \| Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)		4 years
Vesting Period Three [Member] \| Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)		5 years
Core Deposits [Member]
Finite-Lived Intangible Asset, Useful Life (Year)		10 years
Minimum [Member]
Property, Plant and Equipment, Useful Life (Year)		3 years
Maximum [Member]
Property, Plant and Equipment, Useful Life (Year)		40 years
Federal Home Loan Bank Certificates and Obligations (FHLB) [Member]
Stock Value Par or Stated Value per Share (in dollars per share) \| $ / shares		$ 100
CONNECTICUT
Number of Operating Branches		7
NEW YORK
Number of Operating Branches		2