Acquisitions - DoseMe (Details) - USD ($) $ in Thousands		3 Months Ended						9 Months Ended		12 Months Ended
	Jan. 02, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Allocation of the purchase price based on the estimated fair values of the assets acquired and liabilities assumed
Goodwill		$ 150,790						$ 150,790		$ 108,213
Revenue		74,270			$ 54,418			211,484	$ 146,960
Net income (loss)		(8,104)	$ (6,529)	$ (10,979)	10,416	$ (29,026)	$ (18,094)	(25,612)	(36,704)
Amortization expense		6,927			$ 2,782			$ 18,678	$ 7,949
Trade name
Allocation of the purchase price based on the estimated fair values of the assets acquired and liabilities assumed
Weighted average amortization period								7 years		8 years
Developed technology
Allocation of the purchase price based on the estimated fair values of the assets acquired and liabilities assumed
Weighted average amortization period								8 years		7 years 2 months 12 days
Non-competition agreement
Allocation of the purchase price based on the estimated fair values of the assets acquired and liabilities assumed
Weighted average amortization period								5 years		5 years
DoseMe
Acquisition
Issuance of common stock (in shares)	149,053
Cash payment for acquisition-related contingent consideration		8,750
Direct acquisition costs		0						$ 104
Purchase price consideration
Cash consideration at closing, net of post-closing adjustments	$ 10,136
Stock consideration at closing	9,504
Estimated fair value of contingent consideration	8,720
Total fair value of acquisition consideration	28,360
Allocation of the purchase price based on the estimated fair values of the assets acquired and liabilities assumed
Accounts receivable	9
Prepaid expenses and other current assets	110
Goodwill	11,831
Total assets acquired	28,739
Trade accounts payable	(17)
Accrued expenses and other liabilities	(362)
Total purchase price	28,360
Acquisition-related contingent consideration	$ 8,720
Weighted average amortization period	7 years 4 months 24 days
Revenue		$ 88						$ 226
Revenue from Contract with Customer, Product and Service		us-gaap:ServiceMember						us-gaap:ServiceMember
Net income (loss)		$ (1,531)						$ (3,526)
Amortization expense		$ 571						$ 1,712
DoseMe | Maximum
Acquisition
Cash consideration	$ 10,000
Contingent earn out payment	10,000
DoseMe | Trade name
Allocation of the purchase price based on the estimated fair values of the assets acquired and liabilities assumed
Intangible assets	$ 89
Weighted average amortization period	4 years
DoseMe | Developed technology
Allocation of the purchase price based on the estimated fair values of the assets acquired and liabilities assumed
Intangible assets	$ 16,200
Weighted average amortization period	7 years 6 months
DoseMe | Non-competition agreement
Allocation of the purchase price based on the estimated fair values of the assets acquired and liabilities assumed
Intangible assets	$ 500
Weighted average amortization period	5 years