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Stock-based Compensation - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2013	Dec. 31, 2012
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share based compensation expense	$ 997,000	$ 1,275,000	$ 969,000
2005 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation shares authorized under stock option plans	770,000
Percent of the fair value options granted	100.00%
Weighted average remaining contractual term stock options outstanding	2 years 7 months 6 days
Weighted average remaining contractual life for options exercisable	2 years 7 months 6 days
2005 Plan \| Employee Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period	5 years
Stock options, when granted, expiration period	10 years
2010 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation shares authorized under stock option plans				2,500,000	1,350,000
Percent of the fair value options granted	100.00%
Weighted average remaining contractual term stock options outstanding	3 years 1 month 13 days
Weighted average remaining contractual life for options exercisable	3 years 1 month 2 days
Number of options outstanding, Granted	0	0
Unrecognized compensation costs related to unvested stock options	$ 507,000
Unrecognized compensation costs weighted average period	9 months 7 days
2010 Plan \| Employee Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period	5 years
Stock options, when granted, expiration period	10 years
2010 Plan \| Restricted Stock Awards \| Share-based Payment Arrangement, Vesting in Three Years
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period	3 years	3 years
2010 Plan \| Restricted Stock Awards \| Share-based Payment Arrangement, Vesting in Five Years
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period	5 years	5 years