Net Income (Loss) per Common Share - Reconciliation of Basic and Diluted Weighted Average Common Shares Outstanding (Details) - shares	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Schedule of reconciliation of basic and diluted weighted average common shares outstanding
Weighted average common shares outstanding - basic (in shares)	18,341,000	17,723,000	18,152,000	17,634,000
Dilutive common shares issuable in connection with stock plans (in shares)	225,000	0	0	0
Weighted average common shares outstanding - diluted (in shares)	18,566,000	17,723,000	18,152,000	17,634,000