Supplemental Employee Retirement Plan Expense

No definition available.

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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- Definition

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

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- Definition

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

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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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No definition available.

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- Definition

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

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No definition available.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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- Definition

Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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- Definition

This item represents the amount of cash contributions during the period made by the entity to the Employee Stock Ownership Plan (ESOP).

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- Definition

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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- Definition

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

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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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- Definition

The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

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- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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- Definition

Net number of share options (or share units) granted during the period.

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Percentage of vesting of award under share-based payment arrangement.

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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- Definition

Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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- Definition

Number of shares of capital stock issued (purchased by employees) in connection with an employee stock ownership plan.

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Total number of shares issued during the period, including shares forfeited, as a result of Restricted Stock Awards.

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Aggregate value of stock issued during the period as a result of employee stock ownership plan (ESOP).

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Employee Benefits (Narrative) (Details) - USD ($)	3 Months Ended	12 Months Ended
Employee Benefits (Narrative) (Details) - USD ($)	Mar. 31, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	May 31, 2014
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Contributions to the plans		$ 678,000	$ 616,000	$ 622,000
Shares owned by ESOP		514,457	527,705
Employee Stock Ownership Plan (ESOP), Number of Suspense Shares		43,704	66,099
Common stock, shares authorized		20,000,000	20,000,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Net of Forfeitures			0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value		$ 9,000	$ 442,000	24,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value		596,000	$ 396,000	396,000
Stock Issued During Period, Shares, Restricted Stock Award, Gross			2,892
Allocated Share-based Compensation Expense		527,000	$ 590,000	391,000
Employee Service Share-based Compensation, Tax Benefit from Compensation Expense		127,000	$ 142,000	$ 94,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Share-based Awards Other than Options		$ 1,390,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition		1 year 7 months 13 days
Stock Issued During Period, Shares, Employee Stock Ownership Plan		22,395	20,855	19,780
Stock Issued During Period, Value, Employee Stock Ownership Plan		$ 420,000	$ 530,000	$ 485,000
Share-based Payment Arrangement, Tranche One
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Stock Issued During Period, Shares, Restricted Stock Award, Gross		2,763
Share-based Payment Arrangement, Tranche Two
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Stock Issued During Period, Shares, Restricted Stock Award, Gross		10,995
7 Year Vesting Stock Appreciation Rights [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Net of Forfeitures	28,306
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 9.74
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	7 years
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	14.30%
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period	10 years
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate	2.51%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate	2.30%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate	40.84%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term	7 years
5 Year Vesting Stock Appreciation Rights [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Net of Forfeitures	109,819
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 8.41
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	5 years
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	20.00%
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period	10 years
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate	2.43%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate	2.30%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate	35.71%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term	5 years 6 months
Restricted Stock Units (RSUs) [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period			3 years
Restricted Stock Units (RSUs) [Member] \| Share-based Payment Arrangement, Tranche One
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period		2 years
Restricted Stock Units (RSUs) [Member] \| Share-based Payment Arrangement, Tranche Two
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period		4 years
Restricted Stock Units (RSUs) [Member] \| Minimum [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period		3 years
Restricted Stock Units (RSUs) [Member] \| Maximum [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period		5 years
2014 LTIP [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Common stock, shares authorized					500,000
Supplemental Employee Retirement Plan [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Accrued liabilities		$ 9,600,000	$ 6,700,000
Supplemental Employee Retirement Plan Expense		787,000	712,000	669,000
Summit Financial Group Inc. Employee Stock Ownership Plan [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Contributions to the ESOP		$ 816,000	$ 721,000	$ 646,000
Shares owned by ESOP		514,457	527,705
Employee Stock Ownership Plan (ESOP), Number of Suspense Shares		43,704