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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, 2020 USD ($) $ / shares shares	Sep. 30, 2020 $ / shares shares	Aug. 31, 2020 $ / shares shares	May 31, 2020 director $ / shares shares	Mar. 31, 2020 $ / shares shares	Feb. 29, 2020 $ / shares shares	Dec. 31, 2019 $ / shares shares	Oct. 31, 2019 director $ / shares shares	Sep. 30, 2019	Jul. 31, 2019 $ / shares shares	May 31, 2019 director $ / shares shares	Mar. 31, 2019 $ / shares shares	Jan. 31, 2019 director $ / shares shares	Jul. 31, 2018 $ / shares shares	May 31, 2018 director $ / shares shares	May 31, 2017 shares	Dec. 31, 2020 USD ($) $ / shares shares	Dec. 31, 2019 USD ($) $ / shares shares	Dec. 31, 2018 USD ($) $ / shares shares
Share-based Compensation
Approved and authorized maximum number of shares to be issued																		2,400,000
Compensation expense related to stock based awards outstanding \| $																			$ 2,000	$ 2,800	$ 2,200
Granted (in shares)																					374,215
Proceeds received upon exercise of stock options \| $																				$ 35	$ 2,815
Exercise of stock options, shares																			0	7,021	488,303
Total share-based compensation cost not yet recognized \| $			$ 2,400																$ 2,400
Share-based compensation cost not yet recognized, period for recognition																			2 years 2 months 12 days
Total intrinsic value of options exercised \| $																					$ 1,286
Total fair value of shares vested \| $																			$ 329	$ 769	$ 705
Officers And Executives
Share-based Compensation
Vesting period																					3 years
Weighted average grant-date fair value of options granted (in USD per share) \| $ / shares																					$ 7.49
Granted (in shares)																					374,215
Certain Officers
Share-based Compensation
Expense related to purchase of vested stock-based awards \| $																			$ 200
Maximum
Share-based Compensation
Proceeds received upon exercise of stock options \| $																				$ 100
Stock options
Share-based Compensation
Expiration period																		10 years
Forfeiture rate applied to awards																			5.50%
Stock options \| Minimum
Share-based Compensation
Vesting period																		3 years
Stock options \| Maximum
Share-based Compensation
Vesting period																		5 years
Restricted stock
Share-based Compensation
Awards granted in period (in shares)																			1,038,044	757,012	333,864
Grant date fair value (in dollars per share) \| $ / shares																			$ 2.76	$ 2.52	$ 7.47
Forfeiture rate applied to awards																			3.20%
Restricted stock \| Independent Directors
Share-based Compensation
Number of new directors \| director						6				1			5		2		5
Awards granted in period (in shares)						39,823				14,218			45,918		8,427		12,064
Grant date fair value (in dollars per share) \| $ / shares						$ 2.26				$ 4.22			$ 1.96		$ 4.45		$ 7.46
Restricted stock \| Officers And Executives
Share-based Compensation
Vesting period			3 years			3 years	3 years		3 years			3 years	3 years				3 years
Awards granted in period (in shares)			95,000			100,000	170,235		31,500			46,500	62,500				203,752
Grant date fair value (in dollars per share) \| $ / shares			$ 4.92			$ 2.26	$ 3.73		$ 5.08			$ 3.66	$ 1.96				$ 7.46
Restricted stock \| Certain Executives
Share-based Compensation
Vesting percentage	33.30%	33.30%									33.30%
Vesting period				3 years
Awards granted in period (in shares)				25,000				15,121						168,350		2,769
Grant date fair value (in dollars per share) \| $ / shares				$ 2.58				$ 4.96						$ 2.97		$ 9.03
Performance Shares \| Certain Executives
Share-based Compensation
Shares earned based on achievement of objective, percent						100.00%							100.00%				100.00%
Awards granted in period (in shares)						300,000							187,500				67,023
Grant date fair value (in dollars per share) \| $ / shares					$ 1.96	$ 2.26							$ 1.96				$ 7.46
Performance period					1 year	1 year							1 year				3 years
Granted (in shares)					93,750
Performance Shares \| Vesting If Performance Target Is Met or Determination \| Certain Executives
Share-based Compensation
Vesting percentage					50.00%	50.00%							50.00%
Performance Shares \| Vesting On Second And Third Anniversary Of Grant \| Certain Executives
Share-based Compensation
Vesting percentage						25.00%							25.00%
Performance Shares \| Vesting on First and Second Anniversary of Determination \| Certain Executives
Share-based Compensation
Vesting percentage					25.00%