9. Non-Cash Share-Based Employee Compensation (Details) - USD ($) $ / shares in Units, $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2020	Dec. 31, 2019
Compensation Related Costs [Abstract]
Outstanding stock options	569,500
Vested stock options	214,800
Nonvested stock options	354,700
Issued stock options	110,000
Exercised stock options	0
Forfeited stock options	103,600
Expired stock options	65,000
Outstanding stock options	510,900	569,500
Vested stock options	190,300	214,800
Nonvested stock options	320,600	354,700
Outstanding wgt. avg. exercise price	$ 4.16
Vested wgt. avg. exercise price	4.12
Nonvested wgt. avg. exercise price	4.18
Issued wgt. avg. exercise price	3.24
Exercised wgt. avg. exercise price	0.00
Forfeited wgt. avg. exercise price	4.12
Expired wgt. avg. exercise price	4.07
Outstanding wgt. avg. exercise price	3.98	$ 4.16
Vested wgt. avg. exercise price	4.21	4.12
Nonvested wgt. avg. exercise price	$ 3.85	$ 4.18
Outstanding contractual life	7 years 7 months 24 days	6 years 9 months 25 days
Vested contractual life	5 years 11 months 12 days	4 years 2 months 12 days
Nonvested contractual life	8 years 8 months 1 day	8 years 4 months 24 days
Outstanding grant date fair value	$ 1.75
Vested grant date fair value	1.95
Nonvested grant date fair value	1.63
Issued grant date fair value	1.27
Exercised grant date fair value	0.00
Forfeited grant date fair value	1.71
Expired grant date fair value	2.88
Outstanding grant date fair value	1.51
Vested grant date fair value	1.54
Nonvested grant date fair value	1.50
Issued aggregate intrinsic value	$ 0
Exercised aggregate intrinsic value	$ 0
Forfeited aggregate intrinsic value	$ 0
Expired aggregate intrinsic value	$ 0
Outstanding aggregate intrinsic value	$ 45,500	$ 24,000
Vested aggregate intrinsic value	29,000	24,000
Nonvested aggregate intrinsic value	$ 16,500	$ 0