Document And Entity Information	3 Months Ended
	Mar. 31, 2013	Apr. 30, 2013
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2013
Document Fiscal Year Focus	2013
Document Fiscal Period Focus	Q1
Entity Registrant Name	ATEL CAPITAL EQUIPMENT FUND VIII LLC
Entity Central Index Key	0001069152
Current Fiscal Year End Date	--12-31
Trading Symbol	zzhjb
Entity Filer Category	Smaller Reporting Company
Entity Units Outstanding		13,560,188