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Stock-Based Compensation (Restricted Stock Activity) (Details) - Restricted Stock - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Number of Shares
Outstanding, Beginning Balance (in shares)	184,389	139,451	145,588
Granted (in shares)	140,988	126,432	139,451
Vested (in shares)	(110,747)	(81,494)	(145,558)
Canceled/Forfeited (in shares)	0	0	0
Outstanding, Ending Balance (in shares)	214,630	184,389	139,451	145,588
Weighted Average Exercise Price
Outstanding, Beginning Balance (in dollars per share)	$ 25.32	$ 21.34	$ 19.17
Granted (in dollars per share)	24.55	27.06	21.34
Vested (in dollars per share)	23.97	21.20	19.17
Canceled/Forfeited (in dollars per share)	0	0	0
Outstanding, Ending Balance (in dollars per share)	$ 25.51	$ 25.32	$ 21.34	$ 19.17
Weighted Average Remaining Contractual Life (years)
Weighted Average Remaining Contractual Life (years)	8 years 10 months 6 days	8 years 9 months 29 days	9 years 1 month 17 days	9 years 1 month 13 days
Aggregate Intrinsic Value (in thousands)
Aggregate Intrinsic Value, Outstanding	$ 3,529	$ 4,831	$ 4,483	$ 3,246
Aggregate Intrinsic Value, Granted	3,461	3,421	3,007
Aggregate Intrinsic Value, Vested	$ 2,806	$ 2,361	$ 2,963

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Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Grants in Period

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

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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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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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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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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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Weighted average remaining contractual term for equity-based awards excluding options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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Intrinsic value of equity-based compensation awards outstanding. Excludes stock and unit options.

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