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Investments in Unconsolidated Joint Ventures (Investments in Unconsolidated Joint Ventures) (Details) $ in Thousands | 3 Months Ended |
--- | --- | ---
Mar. 31, 2023 USD ($) ft² payments | Dec. 31, 2022 USD ($)
Schedule of Equity Method Investments [Line Items] |  |  |
Other Liabilities |  | $ (465,276) | $ (450,918)
Investments in unconsolidated joint ventures |  | 1,752,617 | 1,715,911
Investments In Affiliates Subsidiaries Associates And Joint Ventures net | [1] | 1,671,124 | 1,630,485
Unconsolidated Joint Ventures [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Other Liabilities |  | $ (81,500) | (85,400)
Square 407 Limited Partnership [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Properties |  | Market Square North |
Ownership Percentage |  | 50.00% |
Other Liabilities | [1] | $ (6,097) | (6,198)
BP/CRF Metropolitan Square LLC [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Properties |  | Metropolitan Square |
Ownership Percentage |  | 20.00% |
Other Liabilities | [1] | $ (38,782) | (37,629)
901 New York Avenue LLC [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Properties |  | 901 New York Avenue |
Ownership Percentage | [2] | 25.00% |
Other Liabilities | [1] | $ (12,311) | $ (12,493)
901 New York Avenue LLC (economic ownership) [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Ownership Percentage |  | 50.00% | 50.00%
WP Project Developer LLC [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Properties |  | Wisconsin Place Land and Infrastructure |
Ownership Percentage | [3] | 33.33% |
Investments in unconsolidated joint ventures | [1] | $ 31,723 | $ 31,971
500 North Capitol Venture LLC [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Properties |  | 500 North Capitol Street, NW |
Ownership Percentage |  | 30.00% |
Other Liabilities | [1] | $ (8,941) | (9,185)
501 K Street LLC [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Properties |  | 1001 6th Street |
Ownership Percentage | [4] | 50.00% |
Investments in unconsolidated joint ventures | [1] | $ 43,661 | 42,922
Potential additonal payments to joint venture partner | payments |  | 2 |
Minimum square footage to make a potential additional payment to joint venture partner (in sqft) | ft² |  | 520,000 |
Podium Developer LLC [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Properties |  | The Hub on Causeway - Podium |
Ownership Percentage |  | 50.00% |
Investments in unconsolidated joint ventures | [1] | $ 45,622 | 46,839
Residential Tower Developer LLC [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Properties |  | Hub50House |
Ownership Percentage |  | 50.00% |
Investments in unconsolidated joint ventures | [1] | $ 42,046 | 45,414
Hotel Tower Developer LLC [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Properties |  | The Hub on Causeway - Hotel Air Rights |
Ownership Percentage |  | 50.00% |
Investments in unconsolidated joint ventures | [1] | $ 12,582 | 12,366
Office Tower Developer LLC [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Ownership Percentage |  | 50.00% |
Investments in unconsolidated joint ventures | [1] | $ 59,811 | 59,716
Office Tower Developer LLC |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Properties |  | 100 Causeway Street |
1265 Main Office JV LLC [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Properties |  | 1265 Main Street |
Ownership Percentage |  | 50.00% |
Investments in unconsolidated joint ventures | [1] | $ 3,605 | 3,465
BNY Tower Holdings LLC [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Properties |  | Dock 72 |
Ownership Percentage | [5] | 50.00% |
Other Liabilities | [1] | $ 15,362 | 19,921
CA-Colorado Center LLC[Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Properties |  | Colorado Center |
Ownership Percentage |  | 50.00% |
Investments in unconsolidated joint ventures | [1] | $ 234,635 | 233,862
7750 Wisconsin Avenue LLC [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Properties |  | 7750 Wisconsin Avenue |
Ownership Percentage |  | 50.00% |
Investments in unconsolidated joint ventures | [1] | $ 51,549 | 52,152
BP-M 3HB Venture LLC [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Properties |  | 3 Hudson Boulevard |
Ownership Percentage |  | 25.00% |
Investments in unconsolidated joint ventures | [1] | $ 115,966 | 116,397
SMBP Venture LP [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Properties |  | Santa Monica Business Park |
Ownership Percentage |  | 55.00% |
Investments in unconsolidated joint ventures | [1] | $ 161,786 | 164,735
Platform 16 Holdings LP [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Properties |  | Platform 16 |
Ownership Percentage | [6] | 55.00% |
Investments in unconsolidated joint ventures | [1] | $ 171,010 | 158,109
Gateway Portfolio Holdings LLC [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Properties |  | Gateway Commons |
Ownership Percentage |  | 50.00% |
Investments in unconsolidated joint ventures | [1] | $ 337,535 | 324,038
Rosecrans-Sepulveda Partners 4, LLC |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Properties |  | Beach Cities Media Campus |
Ownership Percentage |  | 50.00% |
Investments in unconsolidated joint ventures | [1] | $ 26,987 | 27,000
Entity Owning Land And Infrastructure Of Project [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Ownership Percentage |  | 33.33% |
Safeco Plaza REIT LLC |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Properties |  | Safeco Plaza |
Ownership Percentage | [7] | 33.67% |
Investments in unconsolidated joint ventures | [1] | $ 68,196 | 69,785
Safeco Plaza REIT LLC | Company's Share [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Ownership Percentage |  | 33.00% |
360 PAS Holdco LLC |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Properties |  | 360 Park Avenue South |
Ownership Percentage | [8] | 42.21% |
Investments in unconsolidated joint ventures | [1] | $ 116,828 | 114,992
360 PAS Holdco LLC | Company's Share [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Ownership Percentage |  | 35.79% |
360 PAS Holdco LLC | Joint Venture Partner [Member] | Scenario, Plan |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Ownership Percentage |  | 58.00% |
Safeco Partner Entity One [Member] | Company's Share [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Ownership Percentage |  | 1.00% |
Safeco Partner Entity Two | Company's Share [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Ownership Percentage |  | 1.00% |
360 PAS Holdco LLC (indirect ownership) | Company's Share [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Ownership Percentage |  | 5.837% |
360 Park Avenue South Partners Entity | Company's Share [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Ownership Percentage |  | 1.00% |
360 Park Avenue South Partners Entity Two | Company's Share [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Ownership Percentage |  | 1.00% |
PR II BXP Reston Gateway LLC |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Properties |  | Reston Next Residential |
Ownership Percentage | [9] | 20.00% |
Investments in unconsolidated joint ventures | [1] | $ 11,431 | 11,351
PR II BXP Reston Gateway LLC | Joint Venture Partner [Member] | Scenario, Plan |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Ownership Percentage |  | 80.00% |
751 Gateway Holdings LLC |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Properties |  | 751 Gateway |
Ownership Percentage |  | 49.00% |
Investments in unconsolidated joint ventures | [1] | $ 85,430 | 80,714
200 Fifth Avenue JV LLC |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Properties |  | 200 Fifth Avenue |
Ownership Percentage |  | 26.69% |
Investments in unconsolidated joint ventures | [1] | $ 114,919 | $ 120,083
ABXP Worldgate Investments LLC |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Properties |  | 13100 and 13150 Worldgate Drive |
Ownership Percentage |  | 50.00% |
Investments in unconsolidated joint ventures | [1] | $ 17,295 |
[1] | Investments with deficit balances aggregating approximately $81.5 million and $85.4 million at March 31, 2023 and December 31, 2022, respectively, are included within Other Liabilities in the Company’s Consolidated Balance Sheets.
[2] | The Company’s economic ownership has increased based on the achievement of certain return thresholds. At March 31, 2023 and December 31, 2022, the Company’s economic ownership was approximately 50%.
[3] | The Company’s wholly-owned subsidiary that owns Wisconsin Place Office also owns a 33.33% interest in the joint venture entity that owns the land, parking garage and infrastructure of the project.
[4] | Under the joint venture agreement for this land parcel, the partner will be entitled to up to two additional payments from the venture based on increases in total entitled square footage of the project in excess of 520,000 square feet and achieving certain project returns at stabilization.
[5] | This property includes net equity balances from the amenity joint venture.
[6] | This entity is a VIE (See Note 2).
[7] | The Company’s ownership includes (1) a 33.0% direct interest in the joint venture, and (2) an additional 1% interest in each of the two entities through which each partner owns its interest in the joint venture.
[8] | The Company’s ownership includes (1) a 35.79% direct interest in the joint venture, (2) an additional 5.837% indirect ownership in the joint venture, and (3) an additional 1% interest in each of the two entities through which each partner owns its interest in the joint venture. The Company’s partners will fund required capital until their aggregate investment is approximately 58% of all capital contributions; thereafter, the partners will fund required capital according to their percentage interests.
[9] | The Company’s partner will fund required capital until its aggregate investment is approximately 80% of all capital contributions; thereafter, the partners will fund required capital according to their percentage interests.

X
- Definition Total investments in (A) an entity in which the entity has significant influence, but does not have control, (B) subsidiaries that are not required to be consolidated and are accounted for using the equity and or cost method, and (C) an entity in which the reporting entity shares control of the entity with another party or group. Includes long-term advances receivable from a party that is affiliated with the reporting entity by means of direct or indirect ownership. + References No definition available. + Details
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