Document and Entity Information	3 Months Ended
	Mar. 31, 2019 $ / shares shares
Entity Registrant Name	SIMON PROPERTY GROUP INC /DE/
Entity Central Index Key	0001063761
Document Type	10-Q
Document Period End Date	Mar. 31, 2019
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q1
Common stock
Entity Common Stock, Shares Outstanding | shares	308,985,608
Entity Listing, Par Value Per Share | $ / shares	$ 0.0001
Class B common stock
Entity Common Stock, Shares Outstanding | shares	8,000
Entity Listing, Par Value Per Share | $ / shares	$ 0.0001