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Stock-Based Compensation - Narrative (Details) $ / shares in Units, $ in Thousands			1 Months Ended											12 Months Ended
	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2019 USD ($) $ / shares shares	Oct. 31, 2019 $ / shares shares	Sep. 30, 2019	Jul. 31, 2019 $ / shares shares	May 31, 2019 $ / shares shares	Mar. 31, 2019 $ / shares shares	Jan. 31, 2019 director $ / shares shares	Jul. 31, 2018 $ / shares shares	May 31, 2018 $ / shares shares	May 31, 2017 $ / shares shares	May 31, 2011	Dec. 31, 2019 USD ($) $ / shares shares	Dec. 31, 2018 USD ($) $ / shares shares	Dec. 31, 2017 USD ($) $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Approved and authorized maximum number of shares to be issued												2,400,000
Compensation expense related to stock based awards outstanding \| $														$ 2,800	$ 2,200	$ 2,300
Granted (in shares)															374,215	425,204
Granted (in dollars per share) \| $ / shares															$ 7.49	$ 7.22
Proceeds received upon exercise of stock options \| $														$ 35	$ 2,815	$ 1,320
Exercise of stock options, shares														7,021	488,303	229,551
Total share-based compensation cost not yet recognized \| $			$ 2,000											$ 2,000
Share-based compensation cost not yet recognized, period for recognition														1 year 6 months
Total intrinsic value of options exercised \| $															$ 1,286	$ 706
Total fair value of shares vested \| $														$ 769	$ 705	$ 855
Independent Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of new directors \| director									2
Officers And Executives
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period															3 years
Performance period																3 years
Weighted average grant-date fair value of options granted (in USD per share) \| $ / shares															$ 7.49	$ 7.22
Granted (in shares)															374,215	425,204
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Proceeds received upon exercise of stock options \| $														$ 100
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expiration period													10 years
Forfeiture rate applied to options														5.50%
Stock options \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period													3 years
Stock options \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period													5 years
Restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards granted in period (in shares)														757,012	333,864	345,913
Weighted average grant date fair value (in dollars per share) \| $ / shares														$ 2.52	$ 7.47	$ 7.22
Restricted stock \| Independent Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards granted in period (in shares)				14,218			45,918		8,427		12,064	12,465
Weighted average grant date fair value (in dollars per share) \| $ / shares				$ 4.22			$ 1.96		$ 4.45		$ 7.46	$ 7.22
Restricted stock \| Officers And Executives
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			3 years			3 years	3 years				3 years					3 years
Awards granted in period (in shares)			31,500			46,500	62,500			2,769	203,752					213,643
Weighted average grant date fair value (in dollars per share) \| $ / shares			$ 5.08			$ 3.66	$ 1.96			$ 9.03	$ 7.46					$ 7.22
Restricted stock \| Certain Executives
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	33.30%	33.30%			33.30%
Awards granted in period (in shares)								168,350
Weighted average grant date fair value (in dollars per share) \| $ / shares								$ 2.97
Performance Shares \| Certain Executives
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares earned based on achievement of objective, percent							100.00%
Awards granted in period (in shares)							187,500				67,023	69,945
Weighted average grant date fair value (in dollars per share) \| $ / shares							$ 1.96				$ 7.46	$ 7.22
Performance period							1 year				3 years	2 years
Performance Shares \| Vesting If Performance Target Is Met \| Certain Executives
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage							50.00%
Performance Shares \| Vesting On Second And Third Anniversary Of Grant \| Certain Executives
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage							25.00%
2017 LTIP \| Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Forfeiture rate applied to options														3.20%