Organization (Details) ft² in Millions	12 Months Ended
Dec. 31, 2019 ft² Real_Estate_Properties yr shares	Dec. 31, 2018 shares
Real Estate Properties [Line Items]
General and limited partnership interest in the operating partnership (percent)	89.60%	89.70%
Restriction on redemption of OP units from date of issuance (years) \| yr	1
One OP unit is equivalent to one share of Common Stock (in shares) \| shares	1
OP unit conversion rate (in shares) \| shares	1
Number Of series Of preferred units outstanding	1
Number of VIEs - Consolidated	6
Number of VIEs - Total	8
Commercial Real Estate Properties [Member]
Real Estate Properties [Line Items]
Number of real estate properties	196
Net Rentable Area (in sf) \| ft²	52.0
Total Properties Under Construction [ Member]
Real Estate Properties [Line Items]
Number of real estate properties	11
Net Rentable Area (in sf) \| ft²	5.5
Total Office Properties [ Member]
Real Estate Properties [Line Items]
Number of real estate properties	177
Number of VIEs - Consolidated	5
Office Properties Under Construction [Member]
Real Estate Properties [Line Items]
Number of real estate properties	9
Retail Properties [ Member]
Real Estate Properties [Line Items]
Number of real estate properties	12
Residential Properties [Member]
Real Estate Properties [Line Items]
Number of real estate properties	6
Residential Properties Under Construction [Member]
Real Estate Properties [Line Items]
Number of real estate properties	2
Hotel Property [ Member]
Real Estate Properties [Line Items]
Number of real estate properties	1
Series B Cumulative Redeemable Preferred Stock / Unit [Member]
Real Estate Properties [Line Items]
Preferred Stock, Dividend Rate, Percentage	5.25%
Preferred stock / units, shares / units outstanding (in shares / units) \| shares	80,000	80,000
Depositary shares of Series B Cumulative Redeemable Preferred [Member]
Real Estate Properties [Line Items]
Preferred stock / units, shares / units outstanding (in shares / units) \| shares	8,000,000
Series B Preferred Units [Member]
Real Estate Properties [Line Items]
Preferred stock / units, shares / units outstanding (in shares / units) \| shares	80,000

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Number Of Series Of Preferred Units Outstanding.

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Number of VIEs - consolidated

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Number of VIEs - Total

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OP Unit Conversion Rate.

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Restriction On Redemption Of OP Units From Date Of Issuance In Years

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- Definition

Percentage investment held by the managing member or general partner of the limited liability company (LLC) or limited partnership (LP).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 272
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6373374&loc=d3e70478-108055

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Net rentable area for properties owned.

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The number of real estate properties owned as of the balance sheet date.

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The percentage rate used to calculate dividend payments on preferred stock.

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Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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-SubTopic 10
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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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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