Summary of Significant Accounting Policies - AOCI, Simon Property Group, Inc. (Details) $ in Thousands	12 Months Ended
Dec. 31, 2016 USD ($)
Changes in accumulated other comprehensive income (loss)
Beginning balance	$ 4,471,464
Ending balance	4,310,448
Accumulated Other Comprehensive Income (Loss)
Changes in accumulated other comprehensive income (loss)
Beginning balance	(252,686)
Other comprehensive income (loss) before reclassifications	8,567
Amounts reclassified from accumulated other comprehensive income (loss)	129,993
Net current-period other comprehensive income (loss)	138,560
Ending balance	(114,126)
Currency translation adjustments, attributable to parent
Changes in accumulated other comprehensive income (loss)
Beginning balance	(248,285)
Other comprehensive income (loss) before reclassifications	(28,437)
Amounts reclassified from accumulated other comprehensive income (loss)	118,858
Net current-period other comprehensive income (loss)	90,421
Ending balance	(157,864)
Accumulated derivative losses, attributable to parent
Changes in accumulated other comprehensive income (loss)
Beginning balance	(15,161)
Other comprehensive income (loss) before reclassifications	34,400
Amounts reclassified from accumulated other comprehensive income (loss)	11,135
Net current-period other comprehensive income (loss)	45,535
Ending balance	30,374
Net unrealized gains on sale of marketable securities
Changes in accumulated other comprehensive income (loss)
Beginning balance	10,760
Other comprehensive income (loss) before reclassifications	2,604
Net current-period other comprehensive income (loss)	2,604
Ending balance	$ 13,364

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

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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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