Business Combinations - Additional Information (Details) $ in Millions				3 Months Ended
	May 18, 2018 USD ($)	May 01, 2018 USD ($)	Apr. 03, 2018 USD ($)	Mar. 31, 2019 Business	Mar. 31, 2018 Business
Business Acquisition [Line Items]
Business combinations | Business				0	0
UMS
Business Acquisition [Line Items]
Date of acquisition of business			Apr. 03, 2018
Purchase price of acquisition, cash			$ 31.9
PlanetRisk, Inc.
Business Acquisition [Line Items]
Date of acquisition of business		May 01, 2018
Purchase price of acquisition, cash		$ 2.0
Respond B.V.
Business Acquisition [Line Items]
Date of acquisition of business	May 18, 2018
Purchase price of acquisition, cash	$ 2.0
Note payable	0.4
Total purchase price	$ 2.3