Document and Entity Information	12 Months Ended
	Dec. 31, 2018 shares
Document Information [Line Items]
Entity Registrant Name	CREDIT SUISSE GROUP AG
Entity Central Index Key	0001159510
Trading Symbol	CS
Document Type	20-F
Document Period End Date	Dec. 31, 2018
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding	2,550,584,029
Document Fiscal Year Focus	2018
Document Fiscal Period Focus	FY
Bank
Document Information [Line Items]
Entity Registrant Name	CREDIT SUISSE AG
Entity Central Index Key	0001053092
Document Type	20-F
Document Period End Date	Dec. 31, 2018
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding	4,399,680,200
Document Fiscal Year Focus	2018
Document Fiscal Period Focus	FY