Banking Regulation, Increase in Capital

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- Definition

Capital Conservation Buffer, Regulatory Risk-Based Requirement, Full Phase In

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- Definition

Common Stock, Voting Rights, Votes per Share

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- Definition

Shareholders Rights Plan, Acquisition Percentage to Trigger the Exercise of the Right to Purchase

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Shareholders Rights Plan, Right to Purchase Price Per One One-Hundredth of a Share

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- Definition

Stock Issued During Period, Shares, Direct Stock Purchase Plan

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- Definition

Stock Issued During Period, Value, Direct Stock Purchase Plan

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- Definition

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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Face amount or stated value per share of common stock.

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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Amount of paid and unpaid common stock dividends declared with the form of settlement in cash, stock and payment-in-kind (PIK).

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Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

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The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.

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Total number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) issued to shareholders (includes related preferred shares that were issued, repurchased, and remain in the treasury). May be all or portion of the number of preferred shares authorized. Excludes preferred shares that are classified as debt.

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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Number of shares issued during the period from a dividend reinvestment plan (DRIP). A dividend reinvestment plan allows the shareholders to reinvest dividends paid to them by the entity on new issues of stock by the entity.

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Value of stock issued during the period from a dividend reinvestment plan (DRIP). A dividend reinvestment plan allows the holder of the stock to reinvest dividends paid to them by the entity on new issues of stock by the entity.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of subordinated debt (with initial maturities beyond one year or beyond the operating cycle if longer). Subordinated debt places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets.

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Stockholders' Equity - Narrative (Details)	1 Months Ended	6 Months Ended	12 Months Ended
Stockholders' Equity - Narrative (Details)	Sep. 30, 2020 USD ($)	Jun. 30, 2018 USD ($)	Dec. 31, 2020 USD ($) vote $ / shares shares	Dec. 31, 2019 USD ($) shares	Dec. 31, 2018 USD ($) shares	Jul. 07, 2020 USD ($)	Dec. 31, 2017 shares	Jan. 31, 2015 USD ($)
Class of Stock [Line Items]
Common stock, shares authorized (in shares)			40,000,000
Common stock, par value (in usd per share) \| $ / shares			$ 0.01
Common stock, shares issued (in shares)			11,937,795	11,825,331
Common stock, shares outstanding (in shares)			11,937,795	11,825,331
Common stock, voting rights, votes per share \| vote			1
Preferred stock, shares authorized (in shares)			1,000,000
Preferred stock, par value (in usd per share) \| $ / shares			$ 0.01
Preferred stock, shares issued (in shares)			0
Unvested participating restricted stock awards (in shares)			116,174	102,056
Common stock issued under direct stock purchase plan, value \| $			$ 44,000	$ 48,000	$ 94,000
Subordinated debt \| $			$ 73,744,000	$ 14,872,000	14,860,000
Banking regulation, increase in capital \| $	$ 53,000,000.0
Basel III additional capital conservation buffer at full phase-in			2.50%	2.50%
Common stock dividend declared \| $			$ (8,322,000)	$ (7,540,000)	(6,771,000)
Common stock issued under dividend reinvestment plan \| $		$ 1,300,000	1,217,000	1,169,000	1,328,000
Fixed-to Floating Rate Subordinated Notes
Class of Stock [Line Items]
Subordinated debt \| $						$ 60,000,000.0		$ 15,000,000.0
Retained Earnings
Class of Stock [Line Items]
Common stock dividend declared \| $		$ (6,800,000)	$ (8,322,000)	$ (7,540,000)	$ (6,771,000)
Common Stock
Class of Stock [Line Items]
Common stock, shares outstanding (in shares)			11,937,795	11,825,331	11,708,218		11,609,853
Common stock issued under direct stock purchase plan (in shares)			1,869	1,609	2,652
Common stock issued under dividend reinvestment plan, shares			50,506	39,176	37,999
Series A Junior Participating Preferred Stock
Class of Stock [Line Items]
Price per one one-hundredth of a share \| $ / shares			$ 122.50
Minimum acquisition percentage to trigger the exercise of the right to purchase			10.00%