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For an unclassified balance sheet, amounts due from an entity in which the reporting entity shares joint control with another party or group.

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Amount receivable from related parties classified as other.

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For an unclassified balance sheet, amounts due from related parties including affiliates, employees, joint ventures, officers and stockholders, immediate families thereof, and pension funds.

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Receivables to be collected from (obligations owed to) related parties, net as of the balance sheet date where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth.

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Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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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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Reflects the sum of all other revenue and income realized from sales and other transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party during the period.

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Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

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Related Party Transactions (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended		6 Months Ended
	Dec. 31, 2016	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Amounts due from/to related parties
Due from joint ventures		$ 9,975		$ 9,975		$ 9,352
Other		7,009		7,009		11,769
Related party receivables		16,984		16,984		$ 21,121
Alliance Building Services
Related Party Transactions
Profit participation from related party		100	$ 1,000	1,000	$ 1,800
Payments made for services		2,800	5,600	6,700	8,500
Entity with Stephen L Green ownership interest
Related Party Transactions
Property management fees from related party		100	$ 200	300	$ 300
One Vanderbilt \| Marc Holliday
Related Party Transactions
Due from related party		1,400		1,400
One Vanderbilt \| Andrew Mathias
Related Party Transactions
Due from related party		$ 1,000		$ 1,000
One Vanderbilt \| Minimum \| Marc Holliday
Related Party Transactions
Percentage of profits due to investors (as a percentage)	1.50%
One Vanderbilt \| Minimum \| Andrew Mathias
Related Party Transactions
Percentage of profits due to investors (as a percentage)	1.00%
One Vanderbilt \| Maximum \| Marc Holliday
Related Party Transactions
Percentage of profits due to investors (as a percentage)	1.80%
One Vanderbilt \| Maximum \| Andrew Mathias
Related Party Transactions
Percentage of profits due to investors (as a percentage)	1.20%