Document and Entity Information - USD ($) $ / shares in Units, $ in Billions	12 Months Ended
	Dec. 31, 2018	Feb. 15, 2019	Jun. 29, 2018	Dec. 31, 2017
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-K
Document Period End Date	Dec. 31, 2018
Document Fiscal Year Focus	2018
Document Fiscal Period Focus	FY
Amendment Flag	false
Entity Emerging Growth Company	false
Entity Small Business	false
Entity Common Stock, Shares Outstanding		443,255,088
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Shell Company	false
Common Stock, Par or Stated Value Per Share	$ 1.00			$ 1.00
Entity Public Float			$ 30.2