Document And Entity Information	3 Months Ended
	Mar. 31, 2015	May 01, 2015
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		6,637,941
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2015
Document Fiscal Period Focus	Q1
Document Fiscal Year Focus	2015