Property and equipment (Tables)

3 Months Ended

Mar. 31, 2017

Property and equipment

Schedule of property and equipment, net

	Estimated			As of		As of
	useful life			March 31,		December 31,
	(in years)			2017		2016
Equipment	2	-	7	$	999,096	$	998,722
Computer hardware	3	-	5		3,744,736		3,637,938
Furniture and fixtures	5	-	7		257,013		256,889
Leasehold improvements	3	-	10		1,059,643		1,037,386
Total property and equipment, gross					6,060,488		5,930,935
Less: Accumulated depreciation and amortization					(4,415,906)		(4,256,525)
Property and equipment, net				$	1,644,582	$	1,674,410

Schedule of property and equipment depreciation and amortization expense

	Three Months Ended
	March 31,
	2017		2016
Depreciation and amortization expense	$	158,617	$	163,126