Property and equipment (Tables)

9 Months Ended

Sep. 30, 2017

Property and equipment

Schedule of property and equipment, net

	Estimated			As of		As of
	useful life			September 30,		December 31,
	(in years)			2017		2016
Equipment	2	-	7	$	1,070,822	$	998,722
Computer hardware	3	-	5		4,057,362		3,637,938
Furniture and fixtures	5	-	7		258,065		256,889
Leasehold improvements	3	-	10		1,058,023		1,037,386
Total property and equipment, gross					6,444,272		5,930,935
Less: Accumulated depreciation and amortization					(4,791,788)		(4,256,525)
Property and equipment, net				$	1,652,484	$	1,674,410

Schedule of property and equipment depreciation and amortization expense

	Three Months Ended				Nine Months Ended
	September 30,				September 30,
	2017		2016		2017		2016
Depreciation and amortization expense	$	215,488	$	328,181	$	527,526	$	768,740