Revenues - Disaggregated Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Disaggregation of Revenue [Line Items]
Total revenues	$ 330,984	$ 322,432	$ 663,377	$ 622,325
Transferred at Point in Time [Member]
Disaggregation of Revenue [Line Items]
Total revenues	4,473	7,139	10,970	13,944
Transferred over Time [Member]
Disaggregation of Revenue [Line Items]
Total revenues	326,511	315,293	652,407	608,381
Digital Media Segment [Member]
Disaggregation of Revenue [Line Items]
Total revenues	163,987	153,359	326,678	301,042
Digital Media Segment [Member] | Advertising [Member]
Disaggregation of Revenue [Line Items]
Total revenues	120,919	109,961	236,184	215,561
Digital Media Segment [Member] | Subscription [Member]
Disaggregation of Revenue [Line Items]
Total revenues	41,720	40,976	87,148	81,354
Digital Media Segment [Member] | Other [Member]
Disaggregation of Revenue [Line Items]
Total revenues	1,348	2,422	3,346	4,127
Cloud Services Segment [Member]
Disaggregation of Revenue [Line Items]
Total revenues	167,058	169,132	336,842	321,377
Cloud Services Segment [Member] | Subscription [Member]
Disaggregation of Revenue [Line Items]
Total revenues	167,040	168,909	336,788	320,698
Cloud Services Segment [Member] | Other [Member]
Disaggregation of Revenue [Line Items]
Total revenues	18	223	54	679
Corporate [Member]
Disaggregation of Revenue [Line Items]
Total revenues	0	2	1	3
Intersegment Elimination [Member]
Disaggregation of Revenue [Line Items]
Total revenues	$ (61)	$ (61)	$ (144)	$ (97)