Equity - Temporary Equity (Details) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2019 USD ($) item $ / shares shares	Dec. 31, 2018 USD ($) shares
Redeemable preferred stock
Limited partners' preferred interest in the Operating Partnership and noncontrolling redeemable interests in properties	$ 219,061	$ 230,163
Simon Property Group, L.P.
Redeemable preferred stock
Limited partners' preferred interest in the Operating Partnership and noncontrolling redeemable interests in properties	$ 219,061	$ 230,163
7.5% Cumulative Redeemable Preferred Units
Redeemable preferred stock
Number of series of units classified into temporary equity | item	1
Noncontrolling interests redeemable at amounts in excess of fair value	0	0
Preferred stock stated dividend rate percentage	7.50%	7.50%
Temporary equity, shares authorized | shares	260,000	260,000
Temporary equity, shares issued | shares	255,373	255,373
Temporary equity, shares outstanding | shares	255,373	255,373
Limited partners' preferred interest in the Operating Partnership and noncontrolling redeemable interests in properties	$ 25,537	$ 25,537
Cumulative quarterly distributions on preferred units (in dollars per share) | $ / shares	$ 7.50
Temporary equity redemption price (in dollars per share) | $ / shares	100.00
Liquidation preference (in dollars per share) | $ / shares	$ 100.00
7.5% Cumulative Redeemable Preferred Units | Simon Property Group, L.P.
Redeemable preferred stock
Number of series of units classified into temporary equity | item	1
Noncontrolling interests redeemable at amounts in excess of fair value	0	0
Preferred stock stated dividend rate percentage	7.50%	7.50%
Temporary equity, shares authorized | shares	260,000	260,000
Temporary equity, shares issued | shares	255,373	255,373
Temporary equity, shares outstanding | shares	255,373	255,373
Limited partners' preferred interest in the Operating Partnership and noncontrolling redeemable interests in properties	$ 25,537	$ 25,537
Cumulative quarterly distributions on preferred units (in dollars per share) | $ / shares	$ 7.50
Temporary equity redemption price (in dollars per share) | $ / shares	100.00
Liquidation preference (in dollars per share) | $ / shares	$ 100.00
Other noncontrolling redeemable interest
Redeemable preferred stock
Limited partners' preferred interest in the Operating Partnership and noncontrolling redeemable interests in properties	$ 193,524	204,626
Other noncontrolling redeemable interest | Simon Property Group, L.P.
Redeemable preferred stock
Limited partners' preferred interest in the Operating Partnership and noncontrolling redeemable interests in properties	$ 193,524	$ 204,626