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Investments in Unconsolidated Joint Ventures (Balance Sheets of the Unconsolidated Joint Ventures) (Details) - USD ($) $ in Thousands | Sep. 30, 2022 | Dec. 31, 2021
--- | --- | ---
ASSETS |  |  |
Real estate and development in process, net |  | $ 19,427,344 | $ 18,275,954
Total assets |  | 23,726,691 | 22,365,258
LIABILITIES AND MEMBERS'/PARTNERS' EQUITY |  |  |
Mortgage and notes payable, net |  | 3,271,157 | 3,267,914
Other Liabilities |  | 417,255 | 391,441
Members’/Partners’ equity |  | 6,155,618 | 5,834,020
Total liabilities and equity / capital |  | 23,726,691 | 22,365,258
Carying value of the Company's investment in unconsolidated joint ventures |  | 1,593,834 | 1,482,997
Right-of-use assets - finance leases |  | 237,505 | 237,507
Right of use assets - operating leases |  | 167,935 | 169,778
Lease liabilities - finance leases |  | 248,092 | 244,421
Lease liabilities - operating leases |  | 205,008 | 204,561
Unconsolidated Joint Ventures [Member] |  |  |
ASSETS |  |  |
Real estate and development in process, net | [1] | 5,858,271 | 5,579,218
Other assets |  | 655,549 | 586,470
Total assets |  | 6,513,820 | 6,165,688
LIABILITIES AND MEMBERS'/PARTNERS' EQUITY |  |  |
Mortgage and notes payable, net |  | 3,425,972 | 3,214,961
Other Liabilities | [2] | 681,228 | 652,135
Members’/Partners’ equity |  | 2,406,620 | 2,298,592
Total liabilities and equity / capital |  | 6,513,820 | 6,165,688
Company's share of equity |  | 1,180,507 | 1,104,175
Basis differentials | [3] | 346,312 | 341,751
Carying value of the Company's investment in unconsolidated joint ventures | [4] | 1,526,819 | 1,445,926
Right-of-use assets - finance leases |  | 248,900 | 248,900
Right of use assets - operating leases |  | 21,400 | 22,300
Lease liabilities - finance leases |  | 383,000 | 385,500
Lease liabilities - operating leases |  | 30,500 | 30,400
Unconsolidated Joint Ventures [Member] |  |  |
LIABILITIES AND MEMBERS'/PARTNERS' EQUITY |  |  |
Other Liabilities |  | 67,000 | 37,100
Colorado Center |  |  |
LIABILITIES AND MEMBERS'/PARTNERS' EQUITY |  |  |
Basis differentials |  | 302,539 | 304,776
Carying value of the Company's investment in unconsolidated joint ventures | [5] | 234,271 | 231,479
Gateway Commons Complex [Member] |  |  |
LIABILITIES AND MEMBERS'/PARTNERS' EQUITY |  |  |
Basis differentials |  | 51,188 | 51,009
Carying value of the Company's investment in unconsolidated joint ventures | [5] | 314,137 | 327,148
Dock 72 |  |  |
LIABILITIES AND MEMBERS'/PARTNERS' EQUITY |  |  |
Basis differentials |  | (48,753) | (50,051)
Carying value of the Company's investment in unconsolidated joint ventures | [5] | $ 26,947 | $ 27,343
[1] | At September 30, 2022 and December 31, 2021, this amount included right of use assets - finance leases totaling approximately $248.9 million. At September 30, 2022 and December 31, 2021, this amount included right of use assets - operating leases totaling approximately $21.4 million and $22.3 million, respectively.
[2] | At September 30, 2022 and December 31, 2021, this amount included lease liabilities - finance leases totaling approximately $383.0 million and $385.5 million, respectively. At September 30, 2022 and December 31, 2021, this amount included lease liabilities - operating leases totaling approximately $30.5 million and $30.4 million, respectively.
[3] | This amount represents the aggregate difference between the Company’s historical cost basis and the basis reflected at the joint venture level, which is typically amortized over the life of the related assets and liabilities. Basis differentials result from impairments of investments, acquisitions through joint ventures with no change in control and upon the transfer of assets that were previously owned by the Company into a joint venture. In addition, certain acquisition, transaction and other costs may not be reflected in the net assets at the joint venture level. The majority of the Company’s basis differences are as follows:
| September 30, 2022 |  | December 31, 2021
Property | (in thousands)
Colorado Center | $ | 302,539 |  |  | $ | 304,776 |
Gateway Commons | 51,188 |  |  | 51,009 |
Dock 72 | (48,753) |  |  | (50,051) |
These basis differentials (excluding land) will be amortized over the remaining lives of the related assets and liabilities.
[4] | Investments with deficit balances aggregating approximately $67.0 million and $37.1 million at September 30, 2022 and December 31, 2021, respectively, are reflected within Other Liabilities in the Company’s Consolidated Balance Sheets.
[5] | Investments with deficit balances aggregating approximately $67.0 million and $37.1 million at September 30, 2022 and December 31, 2021, respectively, are included within Other Liabilities in the Company’s Consolidated Balance Sheets.

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