Amount of actuarial present value of benefits attributed to employee service rendered, excluding assumptions about future compensation level.

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Weighted average rate for present value of future retirement benefits cash flows, used to determine benefit obligation of defined benefit plan.

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Amount of cost of providing special or contractual termination benefits payable from defined benefit plan.

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Amount of contributions received and expected to be received by defined benefit plan from employer in current fiscal year.

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Amount of net periodic benefit cost (credit) for defined benefit 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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Percentage of employer's matching contributions to a defined contribution plan that vests in a given year.

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The amount of plan compensation cost recognized during the period.

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Fair value of unearned shares held by the employee stock ownership plan (ESOP).

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The shares or units in an ESOP trust that have been assigned to individual participant accounts based on a known formula. IRS rules require allocations to be nondiscriminatory generally based on compensation, length of service, or a combination of both. For any particular participant such shares or units may be vested, unvested, or partially vested.

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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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Shares contributed to the ESOP that have not yet been released, committed to be released, or allocated to participant accounts. Suspense shares generally collateralize ESOP debt.

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Weighted average purchase price of capital shares purchased through an employee stock ownership plan.

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Employee Benefits (Details) - USD ($)		3 Months Ended	12 Months Ended
Employee Benefits (Details) - USD ($)	Mar. 24, 2017	Dec. 31, 2017	Dec. 31, 2017	Dec. 31, 2016
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Matching percentage of eligible compensation			4.00%
Employee stock ownership plan, shares	350,000
Employee stock ownership plan, share purchase price	$ 10.00
Compensation expense		$ 269,344	$ 367,730
Shares committed to be released		21,878	21,878
Shares committed		2,320	2,320
Fair value of unearned ESOP		$ 5,338,545	$ 5,338,545
401(k) Eligible Compensation [Member]
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Vesting percentage			100.00%
401(k) Profit Sharing [Member]
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Vesting percentage			25.00%
Total contribution		$ 311,507	$ 311,507	$ 217,598
Deferred Compensation Agreement [Member]
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Discount rate		3.60%	3.60%
Fully vested obligation			$ 1,689,467
Accrued liability		$ 248,481	248,481	153,409
Deferred compensation benefit (cost)			$ (95,072)	$ 20,267
Deferred Compensation Agreement [Member] \| November 2017 [Member]
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Vesting percentage			25.00%
Deferred Compensation Agreement [Member] \| November 2022 [Member]
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Vesting percentage			50.00%
Deferred Compensation Agreement [Member] \| November 2027 [Member]
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Vesting percentage			75.00%
Deferred Compensation Agreement [Member] \| January 1, 2032 [Member]
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Vesting percentage			100.00%