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Shareholders' Equity - Additional Information (Details)		12 Months Ended
Shareholders' Equity - Additional Information (Details)	Nov. 14, 2019 Director $ / shares shares	Dec. 31, 2019 USD ($) shares	Dec. 31, 2018 USD ($) $ / shares shares	May 31, 2011 shares	Dec. 31, 2005 shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation \| $		$ 149,000	$ 227,000
Unrecognized compensation costs related to non-vested stock options \| $		$ 176,000
Period over which compensation costs related to non-vested stock options recognize		3 years
Tax benefit from recording non-cash expense relates to options granted to employees \| $		$ 0
Employer discretionary contribution to defined plan \| $		$ 0	$ 0
Shares Held in Employee Stock Option Plan, Allocated		473,000	491,000
General and Administrative Expense
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation \| $		$ 141,000	$ 227,000
Executive Officer
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of options granted			105,000
Executive Officer \| Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted average exercise price of options granted \| $ / shares			$ 2.09
Executive Officer \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted average exercise price of options granted \| $ / shares			$ 2.17
Non-employee Board Member
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of options granted			90,000
Weighted average exercise price of options granted \| $ / shares			$ 2.17
Common Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of options granted		0
Restricted Stock Units (RSUs)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized compensation costs related to non-vested stock options \| $		$ 175,000
Period over which compensation costs related to non-vested stock options recognize		3 years
Restricted Stock Units (RSUs) \| General and Administrative Expense
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation \| $		$ 8,000
Employees
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of options granted			40,000
Employees \| Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted average exercise price of options granted \| $ / shares			$ 2.17
Employees \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted average exercise price of options granted \| $ / shares			$ 3.35
2005 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares issuable under 2005 Plan		3,000,000		3,000,000	1,500,000
Number of shares issuable under 2005 Plan		0
2015 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares issuable under 2005 Plan		2,000,000
Number of shares issuable under 2005 Plan		1,325,000	1,294,000
Stock option plan expiry date		Mar. 31, 2015
Weighted average exercise price of options granted \| $ / shares			$ 2.26
2015 Plan \| Restricted Stock Units (RSUs)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares awarded under plan	20,000
Number of independent directors \| Director	4
Vesting percentage	0.33%
Vesting period	3 years
Vesting description		The NEO and employee RSUs will vest on the third anniversary of the Grant Date, or November 14, 2022 (the “Vest Date”)
Vesting period for average stock price	30 days
2015 Plan \| Tier 1 \| Restricted Stock Units (RSUs)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Average stock price \| $ / shares	$ 2.75
Shares vest	133,445
2015 Plan \| Tier 2 \| Restricted Stock Units (RSUs)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Average stock price \| $ / shares	$ 3.50
Shares vest	208,643
2015 Plan \| Tier 3 \| Restricted Stock Units (RSUs)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Average stock price \| $ / shares	$ 4.25
Shares vest	257,078