Document And Entity Information	9 Months Ended
	Sep. 30, 2013	Nov. 08, 2013
Document Information [Line Items]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2013
Document Fiscal Year Focus	2013
Document Fiscal Period Focus	Q3
Trading Symbol	RDGA
Entity Common Stock, Shares Outstanding		1,260,773
Entity Registrant Name	RIDGEFIELD ACQUISITION CORP
Entity Central Index Key	0000812152
Current Fiscal Year End Date	--12-31
Entity Filer Category	Smaller Reporting Company