Segment Information - Operating (loss) income (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024
Segment Reporting Information [Line Items]
Total operating loss	$ (3,924)	$ (2,807)
Loss before income taxes	(5,940)	(4,019)
Corporate, Non-Segment
Segment Reporting Information [Line Items]
Total operating loss	(3,753)	(4,062)
Corporate other expense	(2,016)	(1,212)
Sell-side advertising | Operating Segments
Segment Reporting Information [Line Items]
Total operating loss	(992)	962
Buy-side advertising | Operating Segments
Segment Reporting Information [Line Items]
Total operating loss	$ 821	$ 293