Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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- Definition

Amount, after tax, of accumulated gain (loss) on derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=118930883&loc=d3e637-108580

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- Definition

Fair value of the assets less the liabilities of a derivative or group of derivatives.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=118260190&loc=d3e13433-108611

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- Definition

Fixed interest rate related to the interest rate derivative.

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Fixed interest rate that will be received or paid upon exercise of the interest rate swaption contract.

+ References

No definition available.

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- Definition

Fair value as of the balance sheet date of all derivatives designated as foreign currency fair value hedging instruments.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=117331979&loc=d3e41228-113958

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- Definition

Fair value as of the balance sheet date of interest rate derivative assets, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as assets.

+ References

No definition available.

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- Definition

Number of interest rate derivative instruments held by the entity at the reporting date.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
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-Paragraph 1A
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Summary of Significant Accounting Policies - Derivative Financial Instruments (Details) € in Millions, $ in Millions, ¥ in Billions	Jun. 30, 2019 EUR (€) DerivativeInstrument	Jun. 30, 2019 USD ($) DerivativeInstrument	Dec. 31, 2018 EUR (€) DerivativeInstrument	Dec. 31, 2018 USD ($) DerivativeInstrument	Jul. 10, 2018 USD ($)	Jul. 10, 2018 JPY (¥)	Jun. 30, 2018 EUR (€)	Jun. 30, 2018 USD ($)
Interest rate swap \| Designated as Hedging Instrument
Derivative Financial Instruments
Number of Instruments \| DerivativeInstrument	0	0	0	0
USD-Euro currency forward contract \| May 15, 2019 \| Net Investment Hedging \| Designated as Hedging Instrument
Derivative Financial Instruments
Notional Amount \| €			€ 50.0
Forward contract net, fair value				$ (0.8)
USD-Euro currency forward contract \| May 15, 2020 \| Net Investment Hedging \| Designated as Hedging Instrument
Derivative Financial Instruments
Notional Amount \| €	€ 50.0		50.0
Forward contract net, fair value				(1.5)
USD-Euro currency forward contract \| May 14, 2021 \| Net Investment Hedging \| Designated as Hedging Instrument
Derivative Financial Instruments
Notional Amount \| €	€ 50.0		€ 50.0
Forward contract net, fair value		$ (0.3)		(2.0)
US denominated cross currency swap \| Net Investment Hedging \| Designated as Hedging Instrument
Derivative Financial Instruments
Notional Amount					$ 200.1			$ 150.0
Swapping interest rate					4.38%	4.38%	4.38%	4.38%
Yen denominated cross currency swap \| Net Investment Hedging \| Designated as Hedging Instrument
Derivative Financial Instruments
Notional Amount \| ¥						¥ 22.3
Fixed exchange rate					1.19%	1.19%
Yen denominated cross currency swap \| Other liabilities \| Net Investment Hedging \| Designated as Hedging Instrument
Derivative Financial Instruments
Fair value of cross currency		3.7
Euro denominated cross currency swap \| Net Investment Hedging \| Designated as Hedging Instrument
Derivative Financial Instruments
Notional Amount \| €							€ 121.6
Fixed exchange rate							1.37%	1.37%
Euro denominated cross currency swap \| Deferred costs and other assets \| Net Investment Hedging \| Designated as Hedging Instrument
Derivative Financial Instruments
Interest rate derivative asset, fair value		12.9
Simon Property Group, L.P.
Derivative Financial Instruments
Gross accumulated other comprehensive income related to derivative activities		$ 42.4		$ 37.9