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Amount of cash inflow from exercise of option under share-based payment arrangement.

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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, 2021 USD ($) $ / shares shares	Sep. 30, 2021 $ / shares shares	Aug. 31, 2021 $ / shares shares	May 31, 2021 director $ / shares shares	Dec. 31, 2020 $ / 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	May 31, 2017 shares	Dec. 31, 2021 USD ($) $ / shares shares	Dec. 31, 2020 USD ($) $ / shares shares	Dec. 31, 2019 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 \| $																					$ 2,400	$ 2,000	$ 2,800
Proceeds received upon exercise of stock options \| $																					$ 110		$ 35
Exercise of stock options, shares																					28,546	0	7,021
Total share-based compensation cost not yet recognized \| $			$ 3,200																		$ 3,200
Share-based compensation cost not yet recognized, period for recognition																					2 years 2 months 12 days
Total intrinsic value of options exercised \| $																					$ 50
Total fair value of shares vested \| $																					93	$ 329	$ 769
Certain Officers
Share-based Compensation
Expense related to purchase of vested stock-based awards \| $																					$ 900	$ 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)																					916,531	1,038,044	757,012
Grant date fair value (in dollars per share) \| $ / shares																					$ 4.58	$ 2.76	$ 2.52
Forfeiture rate applied to awards																					3.20%
Restricted stock \| Independent Directors
Share-based Compensation
Number of independent directors receiving awards \| director						6				6							5
Number of new directors \| director														1					2
Awards granted in period (in shares)				18,215		14,975				39,823				14,218			45,918		8,427
Grant date fair value (in dollars per share) \| $ / shares				$ 5.49		$ 6.01				$ 2.26				$ 4.22			$ 1.96		$ 4.45
Restricted stock \| Officers And Executives
Share-based Compensation
Vesting period			3 years			3 years	3 years			3 years	3 years		3 years			3 years	3 years
Awards granted in period (in shares)			139,000			160,000	95,000			100,000	170,235		31,500			46,500	62,500
Grant date fair value (in dollars per share) \| $ / shares			$ 3.75			$ 6.01	$ 4.92			$ 2.26	$ 3.73		$ 5.08			$ 3.66	$ 1.96
Restricted stock \| Certain Executives
Share-based Compensation
Vesting percentage	33.30%	33.30%													33.30%
Vesting period				3 years				3 years
Awards granted in period (in shares)								25,000				15,121						168,350
Grant date fair value (in dollars per share) \| $ / shares								$ 2.58				$ 4.96						$ 2.97
Weighted average grant-date fair value of options granted (in USD per share) \| $ / shares				$ 5.05
Granted (in shares)				9,901
Performance Units \| Certain Executives
Share-based Compensation
Vesting percentage						100.00%
Shares earned based on achievement of objective, percent										100.00%							100.00%
Vesting period						3 years
Awards granted in period (in shares)					259,565					300,000							187,500
Grant date fair value (in dollars per share) \| $ / shares					$ 2.26	$ 6.01			$ 1.96	$ 2.26							$ 1.96
Performance period					1 year				1 year	1 year							1 year
Granted (in shares)									93,750
Performance Units \| Vesting If Performance Target Is Met \| Certain Executives
Share-based Compensation
Vesting percentage					50.00%	100.00%			50.00%	50.00%							50.00%
Awards granted in period (in shares)						240,000
Performance Units \| Vesting On Second And Third Anniversary Of Grant \| Certain Executives
Share-based Compensation
Vesting percentage										25.00%							25.00%
Performance Units \| Vesting on First and Second Anniversary of Determination \| Certain Executives
Share-based Compensation
Vesting percentage					25.00%				25.00%