Commitments and Contingencies (Details) ft² in Thousands	12 Months Ended
Dec. 31, 2019 USD ($) ft²	Jul. 31, 2018 USD ($) ft²
Other Commitments
Guarantees and master leases	$ 1,524,000,000
Outstanding letters of credit	15,880,000
Commitment to fund additional capital to partially owned entities	12,700,000
Other commitment	627,000,000
General Liability
Insurance
Insurance limit per property	300,000,000
Insurance limit per occurrence	300,000,000
All Risk And Rental Value
Insurance
Insurance limit per occurrence	2,000,000,000.0
Earthquake California Properties
Insurance
Insurance limit per occurrence	$ 350,000,000
Vornado deductible, percentage of property value	5.00%
Insurance maximum coverage limit in aggregate	$ 350,000,000
Terrorism Acts
Insurance
Insurance limit per occurrence	6,000,000,000.0
Insurance maximum coverage limit in aggregate	6,000,000,000.0
Non-Certified Acts of Terrorism
Insurance
Insurance maximum coverage limit in aggregate	1,200,000,000
NBCR
Insurance
Insurance limit per occurrence	5,000,000,000.0
Insurance maximum coverage limit in aggregate	5,000,000,000.0
PPIC \| NBCR
Insurance
Insurance deductible	$ 1,430,413
Insurance deductible percentage of balance of covered loss	20.00%
Farley Office and Retail Building
Other Commitments
Square footage of real estate property (in sqft) \| ft²	844
Equity method ownership percentage	95.00%
Farley Office and Retail Building \| General Liability
Insurance
Insurance limit per occurrence	$ 100,000,000
Farley Office and Retail Building \| Terrorism Acts
Insurance
Insurance limit per occurrence	1,000,000,000.0
Insurance maximum coverage limit in aggregate	1,000,000,000.0
Farley Office and Retail Building \| Non-Certified Acts of Terrorism
Insurance
Insurance limit per occurrence	1,000,000,000.0
Insurance maximum coverage limit in aggregate	1,000,000,000.0
Farley Office and Retail Building \| Property and Development Activities
Insurance
Insurance limit per occurrence	2,800,000,000
Insurance maximum coverage limit in aggregate	$ 2,800,000,000.0
Farley Office and Retail Building \| Joint Venture
Other Commitments
Equity method ownership percentage	95.00%
345 Montgomery Street \| Regus PLC
Other Commitments
Contractual obligation (up to)		$ 90,000,000
Subsidiary of Regus PLC \| 345 Montgomery Street
Other Commitments
Square footage of real estate property (in sqft) \| ft²		78
Lessor, lease not yet commenced, term of contract (years)		15 years

Area of a real estate property.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Term of lessor's operating lease not yet commenced, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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Minimum amount of other commitment not otherwise specified in the taxonomy. Excludes commitments explicitly modeled in the taxonomy, including but not limited to, long-term and short-term purchase commitments, recorded and unrecorded purchase obligations, supply commitments, registration payment arrangements, leases, debt, product warranties, guarantees, environmental remediation obligations, and pensions.

+ References

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Commitment To Fund Additional Capital To Partially Owned Entities

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Guarantees And Master Leases

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Insurance deductible

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Insurance deductible, percentage of balance of a covered loss

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Insurance Limit Per Occurrence

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Insurance limit per property.

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Insurance maximum coverage limit in aggregate.

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Vornado deductible, percentage of property value

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