Overview - Narrative (Details) ft² in Millions, $ in Millions	Dec. 31, 2018 USD ($) ft² land_parcel unit
Real Estate Properties [Line Items]
Variable interest entity, assets	$ 8,260
Variable interest entity, assets related to real estate held for investment	7,780
Variable interest entity, liabilities	4,410
Variable interest entity, equity	3,850
Variable interest entity, equity portion attributable to noncontrolling interest	$ 1,450
Wholly Owned and Consolidated Properties [Member]
Real Estate Properties [Line Items]
Number of land parcels not included in portfolio \| land_parcel	2
Wholly Owned and Consolidated Properties [Member] \| Office
Real Estate Properties [Line Items]
Area of real estate portfolio (sq ft) \| ft²	16.6
Wholly Owned and Consolidated Properties [Member] \| Multifamily [Member]
Real Estate Properties [Line Items]
Number of multifamily apartment units \| unit	3,595
Unconsolidated Fund Properties \| Office
Real Estate Properties [Line Items]
Area of real estate portfolio (sq ft) \| ft²	1.8

Area Of Real Estate Portfolio

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- Definition

Number Of Units In Real Estate Portfolio

+ References

No definition available.

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- Definition

Variable Interest Entity, Consolidated, Carrying Amount, Assets, Real Estate Held for Investment

+ References

No definition available.

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- Definition

Variable Interest Entity, Consolidated, Carrying Amount, Equity

+ References

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- Definition

Variable Interest Entity, Consolidated, Carrying Amount, Equity, Portion Attributable to Noncontrolling Interest

+ References

No definition available.

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- Definition

Number of separate real estate development properties located on land subject to ground leases.

+ 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.

+ References

No definition available.

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- Definition

The carrying amount of the consolidated Variable Interest Entity's assets included in the reporting entity's statement of financial position.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (bb)
-URI http://asc.fasb.org/extlink&oid=108788376&loc=d3e5710-111685

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- Definition

The carrying amount of the consolidated Variable Interest Entity's liabilities included in the reporting entity's statement of financial position.

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