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Segment Information (Schedule Of Reconciliation Of Net Operating Income To Net Income) (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2023 | Sep. 30, 2022
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |  |
Net income (loss) attributable to the Company | $ (111,826) | $ 360,977 | $ 70,290 | $ 727,144
Noncontrolling interest-common units of the Operating Partnership | 12,626 | (40,883) | (8,642) | (82,821)
Noncontrolling interest in property partnerships | (20,909) | (18,801) | (59,337) | (54,896)
Interest expense | (147,812) | (111,846) | (424,492) | (317,216)
Company's share of net operating income from joint ventures | (501,881) | (488,908) | (1,496,376) | (1,442,266)
Loss from unconsolidated joint ventures | 247,556 | 3,524 | 261,793 | 1,389
Depreciation and amortization expense | (207,435) | (190,675) | (618,746) | (551,445)
Transaction costs | (751) | (1,650) | (1,970) | (2,146)
General and administrative expense | (31,410) | (32,519) | (131,387) | (110,378)
Unrealized Gain (Loss) on Investments | 51 | 0 | (332) | 0
Gains (losses) from investments in securities | 925 | 1,571 | (2,311) | 8,549
Other Income - assignment fee | 0 | 0 | 0 | (6,624)
Interest and other income (loss) | (20,715) | (3,728) | (48,999) | (6,151)
Gains on sales of real estate | (517) | (262,345) | (517) | (381,293)
Segment Reconciling Items |  |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |  |
Net income (loss) attributable to the Company | (111,826) | 360,977 | 70,290 | 727,144
Noncontrolling interest-common units of the Operating Partnership | (12,626) | 40,883 | 8,642 | 82,821
Noncontrolling interest in property partnerships | 20,909 | 18,801 | 59,337 | 54,896
Interest expense | 147,812 | 111,846 | 424,492 | 317,216
Loss from unconsolidated joint ventures | (247,556) | (3,524) | (261,793) | (1,389)
Depreciation and amortization expense | 207,435 | 190,675 | 618,746 | 551,445
Transaction costs | 751 | 1,650 | 1,970 | 2,146
Operating expense | 3,906 | 3,900 | 13,750 | 11,204
General and administrative expense | 31,410 | 32,519 | 131,387 | 110,378
Unrealized Gain (Loss) on Investments | (51) | 0 | 332 | 0
Gains (losses) from investments in securities | (925) | (1,571) | 2,311 | (8,549)
Other Income - assignment fee | 0 | 0 | 0 | 6,624
Interest and other income (loss) | 20,715 | 3,728 | 48,999 | 6,151
Gains on sales of real estate | 517 | 262,345 | 517 | 381,293
Other revenue | 3,906 | 3,900 | 13,750 | 11,204
Company's share of Net Operating Income | 490,999 | 475,918 | 1,473,449 | 1,407,390
Unconsolidated Joint Ventures [Member] |  |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |  |
Interest expense | (60,737) | (40,678) | (176,786) | (103,270)
Loss from unconsolidated joint ventures | 247,556 | 3,524 | 261,793 | 1,389
Depreciation and amortization expense | (49,840) | (44,132) | (151,051) | (132,089)
Transaction costs | (78) | 65 | (179) | (746)
Unconsolidated Joint Ventures [Member] | Segment Reconciling Items |  |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |  |
Company's share of net operating income from joint ventures | 39,165 | 35,316 | 122,175 | 108,347
Boston Properties Limited Partnership |  |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |  |
Net income (loss) attributable to the Company | (122,696) | 403,578 | 84,232 | 819,195
Noncontrolling interest in property partnerships | (20,909) | (18,801) | (59,337) | (54,896)
Interest expense | (147,812) | (111,846) | (424,492) | (317,216)
Loss from unconsolidated joint ventures | 247,556 | 3,524 | 261,793 | 1,389
Depreciation and amortization expense | (205,679) | (188,969) | (613,446) | (546,271)
Transaction costs | (751) | (1,650) | (1,970) | (2,146)
General and administrative expense | (31,410) | (32,519) | (131,387) | (110,378)
Unrealized Gain (Loss) on Investments | 51 | 0 | (332) | 0
Gains (losses) from investments in securities | 925 | 1,571 | (2,311) | 8,549
Other Income - assignment fee | 0 | 0 | 0 | (6,624)
Interest and other income (loss) | (20,715) | (3,728) | (48,999) | (6,151)
Gains on sales of real estate | (517) | (262,357) | (517) | (385,349)
Boston Properties Limited Partnership | Segment Reconciling Items |  |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |  |
Net income (loss) attributable to the Company | (122,696) | 403,578 | 84,232 | 819,195
Noncontrolling interest in property partnerships | 20,909 | 18,801 | 59,337 | 54,896
Interest expense | 147,812 | 111,846 | 424,492 | 317,216
Loss from unconsolidated joint ventures | (247,556) | (3,524) | (261,793) | (1,389)
Depreciation and amortization expense | 205,679 | 188,969 | 613,446 | 546,271
Transaction costs | 751 | 1,650 | 1,970 | 2,146
Operating expense | 3,906 | 3,900 | 13,750 | 11,204
General and administrative expense | 31,410 | 32,519 | 131,387 | 110,378
Unrealized Gain (Loss) on Investments | (51) | 0 | 332 | 0
Gains (losses) from investments in securities | (925) | (1,571) | 2,311 | (8,549)
Other Income - assignment fee | 0 | 0 | 0 | 6,624
Interest and other income (loss) | 20,715 | 3,728 | 48,999 | 6,151
Gains on sales of real estate | 517 | 262,357 | 517 | 385,349
Other revenue | 3,906 | 3,900 | 13,750 | 11,204
Company's share of Net Operating Income | 490,999 | 475,918 | 1,473,449 | 1,407,390
Management Service [Member] |  |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |  |
Other revenue | (9,284) | (7,465) | (28,122) | (19,650)
Management Service [Member] | Segment Reconciling Items |  |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |  |
Other revenue | 9,284 | 7,465 | 28,122 | 19,650
Management Service [Member] | Boston Properties Limited Partnership |  |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |  |
Other revenue | (9,284) | (7,465) | (28,122) | (19,650)
Management Service [Member] | Boston Properties Limited Partnership | Segment Reconciling Items |  |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |  |
Other revenue | 9,284 | 7,465 | 28,122 | 19,650
Noncontrolling interest - property partnerships [Member] |  |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |  |
Company's share of net operating income from joint ventures | 50,047 | 48,306 | 145,102 | 143,223
Noncontrolling interest - property partnerships [Member] | Segment Reconciling Items |  |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |  |
Company's share of net operating income from joint ventures | 50,047 | 48,306 | 145,102 | 143,223
Noncontrolling interest - property partnerships [Member] | Boston Properties Limited Partnership | Segment Reconciling Items |  |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |  |
Company's share of net operating income from joint ventures | $ 50,047 | $ 48,306 | $ 145,102 | $ 143,223

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