Document And Entity Information - shares	6 Months Ended
	Jul. 02, 2016	Aug. 05, 2016
Document Information [Line Items]
Entity Registrant Name	Cartesian, Inc.
Entity Central Index Key	0001094814
Current Fiscal Year End Date	--01-02
Entity Filer Category	Smaller Reporting Company
Trading Symbol	CRTN
Entity Common Stock, Shares Outstanding		8,986,983
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jul. 02, 2016
Document Fiscal Year Focus	2016
Document Fiscal Period Focus	Q2