Document and Entity Information (USD $)	12 Months Ended
	Dec. 31, 2011	Jan. 31, 2012	Jul. 01, 2011
Document and Entity Information
Entity Registrant Name	SILICON LABORATORIES INC
Entity Central Index Key	0001038074
Document Type	10-K
Document Period End Date	Dec. 31, 2011
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Public Float			$ 1,707,989,934
Entity Common Stock, Shares Outstanding		42,236,172
Document Fiscal Year Focus	2011
Document Fiscal Period Focus	FY