Earnings (Loss) Per Share (Calculation of Basic and Diluted Earnings Per Share) (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2020	Jun. 30, 2019
Earnings Per Share [Abstract]
Net income (loss) attributable to RealNetworks			$ (9,202)		$ (9,754)	$ (7,669)
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest	$ (5,341)		(9,211)		(9,891)	(7,739)
Net income (loss) attributable to RealNetworks					(10,243)	(8,241)
Net income (loss) including noncontrolling interests	(5,554)	$ (4,689)	(9,455)	$ 1,214	(10,243)	(8,241)
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	$ (4,592)		$ (9,694)		$ (10,141)	$ (8,248)
Weighted average common shares outstanding used to compute basic EPS	38,243		37,948		38,236	37,885
Dilutive effect of stock based awards	0		0		0	0
Weighted average common shares outstanding used to compute diluted EPS	38,243		37,948		38,236	37,885
Earnings Per Share, Basic	$ (0.13)		$ (0.24)		$ (0.26)	$ (0.20)
Earnings Per Share, Diluted	$ (0.13)		$ (0.24)		$ (0.26)	$ (0.20)