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Stock-Based Compensation (Restricted Stock Activity) (Details) - Restricted Stock - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Number of Shares
Outstanding, Beginning Balance (in shares)	214,630	184,389	139,451
Granted (in shares)	199,810	140,988	126,432
Vested (in shares)	(134,674)	(110,747)	(81,494)
Canceled/Forfeited (in shares)	0	0	0
Outstanding, Ending Balance (in shares)	279,766	214,630	184,389	139,451
Weighted Average Exercise Price
Outstanding, Beginning Balance (in dollars per share)	$ 25.51	$ 25.32	$ 21.34
Granted (in dollars per share)	17.16	24.55	27.06
Vested (in dollars per share)	24.26	23.97	21.20
Canceled/Forfeited (in dollars per share)	0	0	0
Outstanding, Ending Balance (in dollars per share)	$ 20.15	$ 25.51	$ 25.32	$ 21.34
Weighted Average Remaining Contractual Life (years)
Weighted Average Remaining Contractual Life (years)	8 years 9 months 7 days	8 years 10 months 6 days	8 years 9 months 29 days	9 years 1 month 17 days
Aggregate Intrinsic Value (in thousands)
Aggregate Intrinsic Value, Outstanding	$ 3,430	$ 3,529	$ 4,831	$ 4,483
Aggregate Intrinsic Value, Granted	3,433	3,461	3,421
Aggregate Intrinsic Value, Vested	$ 2,807	$ 2,806	$ 2,361

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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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