Selected Quarterly Financial Data (Unaudited) (Tables)

12 Months Ended

Dec. 31, 2017

Quarterly Financial Information Disclosure [Abstract]

Schedule of Quarterly Financial Information

The following table presents selected unaudited financial data for each of the eight quarters in the two-year period ended December 31, 2017. The Company believes this information reflects all recurring adjustments necessary to fairly state this information when read in conjunction with the Company's financial statements and the related notes. Net loss per common share, basic and diluted, for the four quarters of each fiscal year may not sum to the total for the fiscal year because of the different number of shares outstanding during each period. The results of operations for any quarter are not necessarily indicative of the results to be expected for any future period (in thousands of dollars, except for share and per share data):

Quarter Ended	March 31			June 30			September 30			December 31
2017:
Total revenues	$	21,437		$	23,854		$	25,035		$	28,183
Gross profit		15,100			17,110			18,115			20,476
Net loss		(5,303	)		(6,444	)		(6,524	)		(11,149	)
Net loss per common share, basic and diluted	$	(0.24	)	$	(0.29	)	$	(0.29	)	$	(0.48	)
2016:
Total revenues	$	12,854		$	15,734		$	16,780		$	18,704
Gross profit		8,195			10,578			11,498			12,918
Net loss		(6,126	)		(4,436	)		(4,075	)		(6,266	)
Net loss per common share, basic and diluted	$	(4.34	)	$	(3.12	)	$	(2.80	)	$	(0.37	)