Significant Accounting Policies - AOCI, Simon Property Group, Inc. (Details) $ in Thousands	3 Months Ended
Mar. 31, 2017 USD ($)
Changes in accumulated other comprehensive income (loss)
Beginning balance	$ 4,310,448
Ending balance	4,107,267
Accumulated Other Comprehensive Income (Loss)
Changes in accumulated other comprehensive income (loss)
Beginning balance	(114,126)
Other comprehensive income (loss) before reclassifications	11,008
Amounts reclassified from accumulated other comprehensive income	2,275
Net current-period other comprehensive income	13,283
Ending balance	(100,843)
Currency translation adjustments, attributable to parent
Changes in accumulated other comprehensive income (loss)
Beginning balance	(157,864)
Other comprehensive income (loss) before reclassifications	11,530
Net current-period other comprehensive income	11,530
Ending balance	(146,334)
Accumulated derivative gains, attributable to parent
Changes in accumulated other comprehensive income (loss)
Beginning balance	30,374
Other comprehensive income (loss) before reclassifications	(1,110)
Amounts reclassified from accumulated other comprehensive income	2,275
Net current-period other comprehensive income	1,165
Ending balance	31,539
Net unrealized gains on sale of marketable securities
Changes in accumulated other comprehensive income (loss)
Beginning balance	13,364
Other comprehensive income (loss) before reclassifications	588
Net current-period other comprehensive income	588
Ending balance	$ 13,952

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

No definition available.

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Amount after tax, before reclassification adjustments, of other comprehensive income (loss), attributable to parent.

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Amount after tax of other comprehensive income (loss) attributable to parent entity.

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Amount after tax of reclassification adjustments of other comprehensive income (loss) attributable to parent.

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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