Acquisitions - Consideration (Details) - USD ($) $ in Thousands							8 Months Ended	9 Months Ended
	Feb. 06, 2020	Oct. 04, 2019	Oct. 01, 2019	Aug. 21, 2019	May 24, 2019	Apr. 18, 2019	Sep. 30, 2020	Sep. 30, 2020
Localytics
Business Acquisition [Line Items]
Cash							$ 67,655
Holdback	$ 345
Contingent consideration	1,000
Working capital adjustment	0
Total consideration	$ 69,000
Cash holdback payable, payment period	12 months
Future earn out payments, maximum	$ 1,000
Earn out payment								$ 1,000
Altify
Business Acquisition [Line Items]
Cash		$ 84,000
Holdback		0
Contingent consideration		0
Working capital adjustment		0
Total consideration		$ 84,000
InGenius
Business Acquisition [Line Items]
Cash			$ 26,428
Holdback			3,000
Contingent consideration			4,865
Working capital adjustment			0
Total consideration			$ 34,293
Cash holdback payable, payment period			12 months
Future earn out payments, maximum			$ 15,000
Earn out payment								$ 4,500
Cimpl
Business Acquisition [Line Items]
Cash				$ 23,071
Holdback				2,600
Contingent consideration				0
Working capital adjustment				0
Total consideration				$ 25,671
Cash holdback payable, payment period				12 months
Kapost
Business Acquisition [Line Items]
Cash					$ 45,000
Holdback					5,000
Contingent consideration					0
Working capital adjustment					(601)
Total consideration					$ 49,399
Cash holdback payable, payment period					12 months
Postup
Business Acquisition [Line Items]
Cash						$ 34,825
Holdback						175
Contingent consideration						0
Working capital adjustment						0
Total consideration						$ 35,000
Cash holdback payable, payment period						12 months