Document And Entity Information	9 Months Ended
	Sep. 30, 2013	Nov. 07, 2013
Document Information [Line Items]
Entity Registrant Name	CORNERSTONE BANCSHARES INC
Entity Central Index Key	0001038773
Current Fiscal Year End Date	--12-31
Entity Filer Category	Smaller Reporting Company
Trading Symbol	CSBQ
Entity Common Stock, Shares Outstanding		6,547,074
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2013
Document Fiscal Period Focus	Q3
Document Fiscal Year Focus	2013