Business Segments (Details) $ in Thousands	3 Months Ended						6 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2018 USD ($)	Jun. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Sep. 30, 2017 USD ($)	Jun. 30, 2017 USD ($)	Mar. 31, 2017 USD ($)	Jun. 30, 2018 USD ($)	Jun. 30, 2017 USD ($)	Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($)	Dec. 31, 2018 USD ($) Segment	Dec. 31, 2017 USD ($)
Segment Reporting, Disclosure of Other Information about Entity's Reportable Segments [Abstract]
Number of operating segments | Segment											3
Results of Operations from Business Segments [Abstract]
Revenues	$ 7,729	$ 7,388	$ 6,738	$ 7,456	$ 8,445	$ 7,269	$ 14,126	$ 15,714	$ 21,856	$ 23,169	$ 29,855	$ 31,763
Cost of revenues	3,099	3,549	3,345	3,276	3,173	2,733	6,893	5,906	9,992	9,182	12,735	12,998
Gross profit	4,630	3,839	3,393	4,180	5,272	4,536	7,233	9,808	11,864	13,987	$ 17,120	$ 18,765
Gross profit %											57.30%	59.10%
Allocated operating expenses [Abstract]
Engineering and product development	224	269	338	411	423	475	607	898	831	1,309	$ 1,065	$ 1,711
Selling and marketing expenses	2,487	2,378	2,871	2,492	2,846	2,975	5,249	5,821	7,737	8,312	10,624	11,249
Unallocated operating expenses	2,289	2,411	1,884	1,789	1,840	1,711	4,295	3,551	6,583	5,340	8,786	7,604
Total operating expenses	5,000	5,058	5,093	4,692	5,109	5,161	10,151	10,270	15,151	14,961	20,475	20,564
Income (loss) from operations	(370)	(1,219)	(1,700)	(512)	163	(625)	(2,918)	(462)	(3,287)	(974)	(3,355)	(1,799)
Interest expense, net	(239)	(328)	(363)	(781)	(1,197)	(870)	(691)	(2,067)	(930)	(2,848)	(1,142)	(3,196)
Change in fair value of warrant liability	(1,053)	(263)	40	421	657	(671)	(222)	(14)	(1,275)	407	0	595
Change in fair value of embedded conversion feature			0	1,993	2,903	(1,738)	0	1,165	0	3,158	0	3,158
Other income (expense), net	0	(18)	21	0	6	0	1	6	0	6	200	17
Loss on extinguishment of debentures				(20,160)	0	0		0		(20,160)	0	(20,160)
Income (loss) before income taxes	$ (1,662)	$ (1,828)	$ (2,002)	$ (19,039)	$ 2,532	$ (3,904)	$ (3,830)	$ (1,372)	$ (5,492)	$ (20,411)	(4,297)	(21,385)
Assets											47,507	39,131
Dermatology Recurring Procedures [Member]
Results of Operations from Business Segments [Abstract]
Revenues											21,053	22,954
Dermatology Procedures Equipment [Member]
Results of Operations from Business Segments [Abstract]
Revenues											8,802
Operating Segments [Member] | Dermatology Recurring Procedures [Member]
Results of Operations from Business Segments [Abstract]
Revenues											21,053	22,954
Cost of revenues											7,378	8,337
Gross profit											$ 13,675	$ 14,617
Gross profit %											65.00%	63.70%
Allocated operating expenses [Abstract]
Engineering and product development											$ 855	$ 1,431
Selling and marketing expenses											9,249	9,477
Unallocated operating expenses											0	0
Total operating expenses											10,104	10,908
Income (loss) from operations											3,571	3,709
Interest expense, net											0	0
Change in fair value of warrant liability												0
Change in fair value of embedded conversion feature												0
Other income (expense), net											0	0
Loss on extinguishment of debentures												0
Income (loss) before income taxes											3,571	3,709
Assets											26,789	30,174
Operating Segments [Member] | Dermatology Procedures Equipment [Member]
Results of Operations from Business Segments [Abstract]
Revenues											8,802	8,792
Cost of revenues											5,357	4,436
Gross profit											$ 3,445	$ 4,356
Gross profit %											39.10%	49.50%
Allocated operating expenses [Abstract]
Engineering and product development											$ 210	$ 279
Selling and marketing expenses											1,375	1,772
Unallocated operating expenses											0	0
Total operating expenses											1,585	2,051
Income (loss) from operations											1,860	2,305
Interest expense, net											0	0
Change in fair value of warrant liability												0
Change in fair value of embedded conversion feature												0
Other income (expense), net											0	0
Loss on extinguishment of debentures												0
Income (loss) before income taxes											1,860	2,305
Assets											3,476	4,451
Operating Segments [Member] | Dermatology Imaging [Member]
Results of Operations from Business Segments [Abstract]
Revenues											0	17
Cost of revenues											0	225
Gross profit											$ 0	$ (208)
Gross profit %											0.00%	(1223.50%)
Allocated operating expenses [Abstract]
Engineering and product development											$ 0	$ 1
Selling and marketing expenses											0	0
Unallocated operating expenses											0	0
Total operating expenses											0	1
Income (loss) from operations											0	(209)
Interest expense, net											0	0
Change in fair value of warrant liability												0
Change in fair value of embedded conversion feature												0
Other income (expense), net											0	0
Loss on extinguishment of debentures												0
Income (loss) before income taxes											0	(209)
Other Unallocated Assets [Member]
Allocated operating expenses [Abstract]
Assets											$ 17,242	$ 4,506