Document and Entity Information Document and Entity Information	6 Months Ended
	Jul. 01, 2012	Jul. 30, 2012
Document and Entity Information [Abstract]
Entity Registrant Name	FEI CO
Entity Central Index Key	0000914329
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Document Type	10-Q
Document Period End Date	Jul. 01, 2012
Document Fiscal Year Focus	2012
Document Fiscal Period Focus	Q2
Amendment Flag	false
Entity Common Stock, Shares Outstanding		38,075,503