Liquidity and Going Concern - Narrative (Details) - USD ($)		1 Months Ended	3 Months Ended
	Jan. 25, 2018	Oct. 31, 2017	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017	Dec. 31, 2016
Line of Credit Facility [Line Items]
Cash			$ 3,068,000	$ 1,110,000	$ 3,946,000	$ 1,140,000
Working capital			3,789,000
Debt			0		1,563,000
Net loss			1,285,000	668,000
Net cash used in operating activities			472,000	(18,000)
Cash paid for interest payments on then-existing indebtedness			316,000	266,000
Outstanding principal, debt obligations			0		$ 1,800,000
Issuance of preferred stock, net of expenses			1,527,000
Principal payment made			1,832,000	$ 0
Western Alliance Bank
Line of Credit Facility [Line Items]
Principal payment made			$ 800,000
Preferred Stock | Series C Preferred Stock
Line of Credit Facility [Line Items]
Issuance of stock (in shares)	1,750		1,750
Dividend rate, percentage	0.00%
Issuance of preferred stock, net of expenses	$ 1,527,000
Preferred Stock | Series B Preferred Stock
Line of Credit Facility [Line Items]
Issuance of stock (in shares)		2,800
Dividend rate, percentage			0.00%