Acquisitions - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Feb. 06, 2020	Dec. 31, 2019	Oct. 04, 2019
Business Acquisition [Line Items]
Goodwill	$ 379,486		$ 379,486			$ 346,134
Transaction costs, excluding integration and transformation costs	200	$ 3,600	3,500	$ 4,000
Localytics
Business Acquisition [Line Items]
Revenues			7,100
Goodwill					$ 40,109
Altify
Business Acquisition [Line Items]
Deferred tax liabilities			1,000
Goodwill							$ 34,426
All acquisitions
Business Acquisition [Line Items]
Goodwill	$ 154,500		$ 154,500
Goodwill deductible for tax purposes						$ 6,200