Document and Entity Information - $ / shares	9 Months Ended
	Sep. 30, 2017	Oct. 31, 2017	Dec. 31, 2016
Entity Registrant Name	SUNTRUST BANKS INC
Entity Central Index Key	0000750556
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Document Type	10-Q
Document Period End Date	Sep. 30, 2017
Document Fiscal Year Focus	2017
Document Fiscal Period Focus	Q3
Amendment Flag	false
Entity Common Stock, Shares Outstanding		476,033,241
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Common Stock, Par or Stated Value Per Share	$ 1.00		$ 1.00