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Stock Option Plan Narrative Data (Details) - USD ($)		12 Months Ended
Stock Option Plan Narrative Data (Details) - USD ($)	Mar. 31, 2019	Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options outstanding		5,500	7,500
Stock based compensation expense		$ 165,000	$ 120,000
Exercise of stock options		44,000	$ 0
Unrecognized compensation cost related to unvested stock option grants		$ 0
2014 Equity Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized for equity awards		50,000
Stock options granted		0	0
Stock options outstanding		4,500	4,500
Stock options exercisable		4,500
2008 ISO Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options outstanding		1,000	3,000
Stock options exercisable		1,000
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Unvested RSUs		13,881	6,043
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Intrinsic value at grant date of stock options		$ 0
Requisite service period		1 year
Vesting period		1 year
Contractual term		7 years
Stock based compensation expense		$ 0	$ 0
Time-Based [Member] \| Restricted Stock Units (RSUs) [Member] \| 2014 Equity Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Performance-Based [Member] \| Restricted Stock Units (RSUs) [Member] \| 2014 Equity Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	2 years
Executive Employee [Member] \| Restricted Stock Units (RSUs) [Member] \| 2014 Equity Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense, unvested RSUs		$ 492,000	$ 297,000
Number of Unvested RSUs		12,696
Nonemployee Director [Member] \| Restricted Stock Units (RSUs) [Member] \| 2014 Equity Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense, unvested RSUs		$ 18,000
Number of Unvested RSUs		1,185