Document and Entity Information - shares	3 Months Ended	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2021	Oct. 29, 2021
Document Information [Line Items]
Document Type		10-Q
Document Quarterly Report	true
Amendment Flag		false
Document Period End Date		Sep. 30, 2021
Document Transition Report		false
Document Fiscal Year Focus		2021
Document Fiscal Period Focus		Q3
Trading Symbol		RNWK
Entity Registrant Name		RealNetworks, Inc.
Entity Central Index Key		0001046327
Entity File Number		1-37745
Current Fiscal Year End Date		--12-31
Entity Incorporation, State or Country Code		WA
Entity Tax Identification Number		91-1628146
City Area Code		(206)
Local Phone Number		674-2700
Entity Address, Address Line One		1501 First Avenue South, Suite 600
Entity Address, City or Town		Seattle
Entity Address, State or Province		WA
Entity Address, Postal Zip Code		98134
Entity Filer Category		Non-accelerated Filer
Entity Interactive Data Current		Yes
Entity Current Reporting Status		Yes
Entity Small Business		true
Entity Emerging Growth Company		false
Entity Shell Company		false
Entity Common Stock, Shares Outstanding			47,130,385
Security Exchange Name	NASDAQ	NASDAQ
Common Stock [Member]
Document Information [Line Items]
Title of 12(b) Security	Common Stock, Par Value $0.001 per share	Common Stock, Par Value $0.001 per share
Convertible Preferred Stock [Member]
Document Information [Line Items]
Title of 12(b) Security	Preferred Share Purchase Rights	Preferred Share Purchase Rights