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Equity and Stock-Based Compensation - Additional Information (Details) - USD ($)				3 Months Ended		12 Months Ended				84 Months Ended	120 Months Ended
	Feb. 10, 2020	Nov. 29, 2018	Mar. 28, 2018	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 1996	Dec. 31, 2015	Dec. 31, 2014	Apr. 30, 2007
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, par value						$ 0.01	$ 0.01
Stock-based compensation expense						$ 326,000	$ 573,000	$ 855,000
Compensation cost on non-vested stock options not yet recognized						$ 100,000
Compensation cost, expected weighted-average recognition period						1 year 18 days
Shares available to grant						1,167,678
2007 Employee Stock Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available to grant						1,083,744
2007 Employee Stock Incentive Plan \| Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available to grant												500,000
Number of additional shares authorized										2,500,000
Non-Employee Directors Stock Option Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available to grant						83,934
Non-Employee Directors Stock Option Plan \| Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of additional shares authorized											400,000
Share-based compensation, shares issued									100,000
2018 Stock Repurchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock repurchase program period			1 year
Authorized stock repurchase amount			$ 4,000,000
Common stock, par value			$ 0.01
Shares repurchased and retired during the period								771,149
Total cost of shares repurchased and retired								$ 4,000,000.0
Average price per share of shares repurchased								$ 5.19
2019 Stock Repurchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock repurchase program period		1 year
Authorized stock repurchase amount		$ 4,000,000
Common stock, par value		$ 0.01
Shares repurchased and retired during the period					0
2020 Stock Repurchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock repurchase program period	1 year
Authorized stock repurchase amount	$ 4,000,000
Shares repurchased and retired during the period				366,000
Total cost of shares repurchased and retired				$ 2,000,000.0
Average price per share of shares repurchased				$ 5.46
Remaining amount under repurchase program						$ 2,000,000