Period that retirement benefit payments are guaranteed to be disbursed to a participant under a defined benefit plan.

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Number of participants eligible for the defined benefit plan or plans described.

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- Definition

The percent of safe harbor contributions made by the Bank.

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Represents the vesting period for defined contribution plan.

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Value of input used to measure ESOP liability.

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Represents the amount of employee stock ownership plan (ESOP) interest and principal payments from ESOP.

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Fair value per share.

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- Definition

Represents the amount of loan to employee stock ownership plan.

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The amount of cash paid to nonqualified deferred compensation plan.

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Amount of contributions made by employer into fund established for purposes of making future disbursement to individual in accordance with deferred compensation arrangement.

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No definition available.

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Aggregate carrying value as of the balance sheet date of the liabilities for all deferred compensation arrangements. Represents currently earned compensation under compensation arrangements that is not actually paid until a later date.

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No definition available.

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Amount of discretionary contributions made by an employer to a defined contribution plan.

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Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

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No definition available.

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Percentage employer matches of the employee's percentage contribution matched.

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The amount of plan compensation cost recognized during the period.

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The shares that, although not legally released, will be released by a future scheduled and committed debt service payment and will be allocated to employees for service rendered in the current accounting period. The ESOP documents typically define the period of service to which the shares relate. ESOP shares are released to compensate employees directly, to settle employer liabilities for other employee benefits, and to replace dividends on allocated shares that are used for debt service.

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Sum of the allocated, committed-to-be-released and suspense shares of the entity held by the plan.

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Amount of cost (reversal of cost) for pension and other postretirement benefits.

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No definition available.

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Amount of liability, recognized in statement of financial position, for defined benefit pension and other postretirement plans.

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Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

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Note 10 - Employment Benefit and Retirement Plans (Details Textual)	1 Months Ended	12 Months Ended
	Nov. 30, 2018 USD ($)	Dec. 31, 2019 USD ($) $ / shares shares	Dec. 31, 2018 USD ($) $ / shares shares	Oct. 11, 2016 USD ($) $ / shares shares	Sep. 19, 2007	Jul. 08, 2005 USD ($) $ / shares shares
Loan to Employee Stock Ownership Plan				$ 1,907,160		$ 763,140
Employee Stock Ownership Plan (ESOP), Shares in ESOP, Total \| shares		253,326	253,412	190,716		76,314
Sale of Stock, Price Per Share \| $ / shares				$ 10		$ 10
Employee Stock Ownership Plan ESOP Interest and Principal Payments from ESOP		$ 239,000
Employee Stock Ownership Plan (ESOP), Number of Committed-to-be-Released Shares \| shares		18,780	18,779
Fair Value Per Share \| $ / shares		$ 13.38	$ 13.76
Employee Stock Ownership Plan (ESOP), Compensation Expense		$ 251,361	$ 258,357
Defined Contribution Plan, Employer Matching Contribution, Percent of Match		50.00%
Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay		6.00%
Defined Contribution Plan, Safe Harbor Contributions, Percent		3.00%
Defined Contribution Plan, Vesting Period		6 years
Defined Contribution Plan, Employer Discretionary Contribution Amount		$ 189,624	162,090
Deferred Compensation Arrangement with Individual, Contributions by Employer		75,884	73,409
Deferred Compensation Liability, Current and Noncurrent, Total		1,780,544	1,538,862
Payments to Nonqualified Deferred Compensation Plan	$ 33,000
Supplemental Employee Retirement Plan [Member]
Pension and Other Postretirement Benefits Cost (Reversal of Cost), Total		75,252	(3,367)
Supplemental Employee Retirement Plan [Member] \| Other Liabilities [Member]
Liability, Defined Benefit Plan, Total		590,953	541,392
Director Retirement Plan [Member]
Liability, Defined Benefit Plan, Total		$ 305,400	$ 285,053
Defined Benefit Plan, Number of Participants		5	5
Defined Benefit Plan, Guaranteed Payment Term		10 years
Director Retirement Plan [Member] \| Former Members of Twin Oak's Board of Directors [Member]
Defined Benefit Plan, Number of Participants		6
Director Retirement Plan [Member] \| Other Liabilities [Member]
Liability, Defined Benefit Plan, Total		$ 305,400	$ 285,053
Measurement Input, Discount Rate [Member]
Employee Stock Owernship Plan Liability, Measurement Input					0.045