Consolidated Statement of Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Accumulated Other Comprehensive Loss	Accumulated Deficit
Beginning balance (in shares) at Dec. 31, 2017		20,768,401
Beginning balance at Dec. 31, 2017	$ 91,415	$ 2	$ 174,944	$ (2,403)	$ (81,128)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of stock under Company plans, net of shares withheld for tax (in shares)		820,999
Issuance of stock under Company plans, net of shares withheld for tax	(3,763)		(3,763)
Issuance of stock, net of issuance costs	(21)		(21)
Stock-based compensation	10,380		10,380
Foreign currency translation adjustment	(2,427)			(2,427)
Net loss	(12,641)				(12,641)
Ending balance (in shares) at Sep. 30, 2018		21,589,400
Ending balance at Sep. 30, 2018	89,235	$ 2	181,540	(4,830)	(87,477)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Unrealized loss on interest rate swap	0
Unrealized translation loss on foreign currency denominated intercompany loans	0
Beginning balance (in shares) at Jun. 30, 2018		21,516,738
Beginning balance at Jun. 30, 2018	89,754	$ 2	178,062	(5,083)	(83,227)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of stock under Company plans, net of shares withheld for tax (in shares)		72,662
Issuance of stock under Company plans, net of shares withheld for tax	(303)		(303)
Stock-based compensation	3,781		3,781
Foreign currency translation adjustment	253			253
Net loss	(4,250)				(4,250)
Ending balance (in shares) at Sep. 30, 2018		21,589,400
Ending balance at Sep. 30, 2018	89,235	$ 2	181,540	(4,830)	(87,477)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Unrealized loss on interest rate swap	0
Unrealized translation loss on foreign currency denominated intercompany loans	$ 0
Beginning balance (in shares) at Dec. 31, 2018	21,489,112	21,489,112
Beginning balance at Dec. 31, 2018	$ 87,307	$ 2	180,481	(7,501)	(85,675)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock in business combination (in shares)		7,898
Issuance of common stock in business combination	(30)		(30)
Issuance of stock under Company plans, net of shares withheld for tax (in shares)		(30,917)
Issuance of stock under Company plans, net of shares withheld for tax	(5,643)		(5,643)
Issuance of stock, net of issuance costs (in shares)		3,795,000
Issuance of stock, net of issuance costs	151,114	$ 1	151,113
Stock-based compensation	18,716		18,716
Foreign currency translation adjustment	(681)			(681)
Net loss	$ (25,506)				(25,506)
Ending balance (in shares) at Sep. 30, 2019	25,261,093	25,261,093
Ending balance at Sep. 30, 2019	$ 218,288	$ 3	344,637	(15,171)	(111,181)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Unrealized loss on interest rate swap	(3,379)
Unrealized translation loss on foreign currency denominated intercompany loans	(3,610)			(3,610)
Beginning balance (in shares) at Jun. 30, 2019		25,247,707
Beginning balance at Jun. 30, 2019	232,972	$ 3	338,732	(6,889)	(98,874)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock in business combination (in shares)		4,247
Issuance of common stock in business combination	0		0
Issuance of stock under Company plans, net of shares withheld for tax (in shares)		9,139
Issuance of stock under Company plans, net of shares withheld for tax	(1,243)		(1,243)
Issuance of stock, net of issuance costs	(39)		(39)
Stock-based compensation	7,187		7,187
Foreign currency translation adjustment	(1,293)			(1,293)
Net loss	$ (12,307)				(12,307)
Ending balance (in shares) at Sep. 30, 2019	25,261,093	25,261,093
Ending balance at Sep. 30, 2019	$ 218,288	$ 3	$ 344,637	(15,171)	$ (111,181)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Unrealized loss on interest rate swap	(3,379)			(3,379)
Unrealized translation loss on foreign currency denominated intercompany loans	$ (3,610)			$ (3,610)