Stock-Based Compensation (Details) - USD ($)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Jul. 11, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	114,000.0	10,000.0	27,000.0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value	$ 1,800,000	$ 800,000	$ 600,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value	$ 17.11	$ 17.11	$ 17.11
Vesting Terms Range Minimum (in years)	0
Vesting Terms Range Maximum (in years)	4
Vesting Share Price Range Minimum	$ 18.12
Vesting Share Price Range Maximum	23.37
Stock-based Compensation	$ 2,100,000	$ 500,000	$ 500,000
Restricted Stock Shares Authorized				900,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	200,000
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized	$ 400,000
Share-based Compensation Arrangement by Share-based Payment Award, Grants in Period, Weighted Average Exercise Price, Beginning of Year	$ 21.31	$ 21.82	$ 21.53
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward]
Unvested at beginning of year, Number of Restricted Stock Awards (in shares)	26,500	53,700	53,000.0
Unvested at end of year, Number of Restricted Stock Awards (in shares)	52,150	26,500	53,700
Share-based Compensation Arrangement by Share-based Payment Award, Grants in Period, Weighted Average Exercise Price, End of Year	$ 20.55	$ 21.31	$ 21.82
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 19.88	$ 18.58	$ 22.98
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period	(87,900)	(35,700)	(25,300)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value	$ 19.93	$ 21.48	$ 22.07
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period	(500)	(1,500)	(1,000.0)
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Period for Recognition (in years)	8 months 12 days

Restricted Stock Shares Authorized

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Vesting Share Price Range Maximum

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Vesting Share Price Range Minimum

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Vesting Terms Range Minimum

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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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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 noncash expense for share-based payment arrangement.

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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- Definition

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

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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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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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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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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