CONSOLIDATED STATEMENT OF CHANGES IN STOCKHOLDERS' EQUITY - USD ($) shares in Thousands, $ in Thousands	Total	Preferred Stock	Common Stock	Additional Paid-In Capital	Retained Earnings (Accumulated Deficit)
Beginning balance (in shares) at Dec. 31, 2016		976	30,860
Beginning balance, amount at Dec. 31, 2016	$ 26,223	$ 1	$ 31	$ 49,625	$ (23,434)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Options exercised (in shares)			21
Options exercised	275			275
Conversion of Series B convertible preferred to common stock (in shares)		(976)	1,951
Conversion of Series B convertible preferred to common stock	0	$ (1)	$ 2	(1)
Stock based compensation	532			532
Stock issued to acquire options and warrants	(275)			(275)
Net income (loss)	(4,238)				(4,238)
Ending balance, amount at Sep. 30, 2017	22,517	$ 0	$ 33	50,156	(27,672)
Ending balance (in shares) at Sep. 30, 2017		0	32,832
Beginning balance (in shares) at Dec. 31, 2017		0	32,878
Beginning balance, amount at Dec. 31, 2017	22,032	$ 0	$ 33	50,495	(28,496)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Options exercised (in shares)			1,278
Options exercised	3,103			3,103
Warrant exercised (in shares)			40
Warrants exercised	95			95
Stock based compensation	1,238			1,238
Stock issued to acquire options and warrants (in shares)			(576)
Stock issued to acquire options and warrants	(3,133)			(3,133)
Net income (loss)	67,262				67,262
Ending balance, amount at Sep. 30, 2018	$ 90,597	$ 0	$ 33	$ 51,798	$ 38,766
Ending balance (in shares) at Sep. 30, 2018		0	33,620