Equity (Details) $ / shares in Units, $ in Millions			9 Months Ended
	May. 14, 2015 USD ($) shares	Apr. 02, 2015 USD ($)	Sep. 30, 2015 item $ / shares shares
Limited Partners
Equity
Units Redeemed (in units)	944,359
Value of units redeemed | $	$ 162.7
Simon Property Group, Inc
Equity
Period common stock is authorized to repurchase		24 months
Shares repurchased (in shares)			1,903,340
Average share price repurchased (in dollars per share) | $ / shares			$ 180.19
Simon Property Group, Inc | Maximum
Equity
Common stock authorized for repurchase | $		$ 2,000.0
Partnership agreement | Limited Partners
Equity
Number of limited partners who received common stock | item			8
Exchange of units for common stock (in units)			486,802