Summary of Significant Accounting Policies - Rollforward Of Noncontrolling Interest, Simon Group Property L.P. (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Noncontrolling interests:
Net income attributable to noncontrolling nonredeemable interests	$ 83,224	$ 94,176
Distributions to noncontrolling nonredeemable interest holders	(96,562)	(92,012)
Contributions by noncontrolling interests, net, and other	(2)	24
Simon Property Group, L.P.
Noncontrolling interests:
Noncontrolling nonredeemable interests in properties, beginning of period	7,398	3,738
Net income attributable to noncontrolling nonredeemable interests	148	527
Distributions to noncontrolling nonredeemable interest holders	(552)	(489)
Contributions by noncontrolling interests, net, and other		24
Noncontrolling nonredeemable interests in properties, end of period	$ 6,994	$ 3,800

Increase in noncontrolling interests resulting from the contributions and other, net.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

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- Definition

The consolidated profit or loss for the period, net of income taxes, of the portion attributable to the noncontrolling interest and excluding preferred distributions and income attributable to redeemable noncontrolling interests in consolidated properties.

+ References

No definition available.

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- Definition

Decrease in noncontrolling interest balance from payment of dividends or other distributions by the non-wholly owned subsidiary or partially owned entity, included in the consolidation of the parent entity, to the noncontrolling interest holders.

+ References

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- Definition

Total of all Partners' Capital (deficit) items which is directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest).

+ References

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