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Segment Information (Schedule Of Reconciliation Of Net Operating Income To Net Income) (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |  |
Net income attributable to the Company's common shareholders / unitholders | $ 164,318 | $ 128,681 | $ 262,431 | $ 304,682
Preferred Stock Dividends / Distributions | (2,625) | (2,625) | (5,250) | (5,250)
Noncontrolling interest-common units of the Operating Partnership | (19,036) | (14,859) | (30,627) | (35,311)
Noncontrolling interest in property partnerships | (17,482) | (14,400) | (36,312) | (31,634)
Interest expense | (102,357) | (92,204) | (203,366) | (182,424)
Company's share of net operating from joint ventures | (454,301) | (406,678) | (902,016) | (808,137)
Depreciation and amortization expense | (177,411) | (156,417) | (342,005) | (322,214)
Transaction costs | (417) | (474) | (877) | (495)
General and administrative expense | (35,071) | (28,468) | (76,833) | (64,362)
Gains from investments in securities | (1,165) | (505) | (4,134) | (379)
Interest and other income | (3,615) | (2,579) | (7,368) | (4,227)
Income from unconsolidated joint ventures | (47,964) | (769) | (48,177) | (1,230)
Business Intersegment, Eliminations [Member] |  |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |  |
Net income attributable to the Company's common shareholders / unitholders | 164,318 | 128,681 | 262,431 | 304,682
Preferred Stock Dividends / Distributions | 2,625 | 2,625 | 5,250 | 5,250
Noncontrolling interest-common units of the Operating Partnership | 19,036 | 14,859 | 30,627 | 35,311
Noncontrolling interest in property partnerships | 17,482 | 14,400 | 36,312 | 31,634
Interest expense | 102,357 | 92,204 | 203,366 | 182,424
Impairment loss | 0 | 0 | 24,038 | 0
Depreciation and amortization expense | 177,411 | 156,417 | 342,005 | 322,214
Transaction costs | 417 | 474 | 877 | 495
Payroll and related costs from management service contracts | 2,403 | 1,970 | 5,798 | 4,855
General and administrative expense | 35,071 | 28,468 | 76,833 | 64,362
Gains from investments in securities | 1,165 | 505 | 4,134 | 379
Interest and other income | 3,615 | 2,579 | 7,368 | 4,227
(Losses) gains on sales of real estate | 1,686 | 18,292 | 781 | 114,689
Income from unconsolidated joint ventures | 47,964 | 769 | 48,177 | 1,230
Direct reimbursement of payroll and related costs from management service contracts | 2,403 | 1,970 | 5,798 | 4,855
Company's Share of Net Operating Income | 433,454 | 379,856 | 859,433 | 751,466
Boston Properties Limited Partnership |  |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |  |
Net income attributable to the Company's common shareholders / unitholders | 185,715 | 145,961 | 299,097 | 346,868
Preferred Stock Dividends / Distributions | (2,625) | (2,625) | (5,250) | (5,250)
Noncontrolling interest in property partnerships | (17,482) | (14,400) | (36,312) | (31,634)
Interest expense | (102,357) | (92,204) | (203,366) | (182,424)
Depreciation and amortization expense | (175,199) | (154,474) | (337,881) | (318,327)
Transaction costs | (417) | (474) | (877) | (495)
Payroll and related costs from management service contracts |  |  | (5,798) | (4,855)
General and administrative expense | (35,071) | (28,468) | (76,833) | (64,362)
Gains from investments in securities | (1,165) | (505) | (4,134) | (379)
Interest and other income | (3,615) | (2,579) | (7,368) | (4,227)
Income from unconsolidated joint ventures | (47,964) | (769) | (48,177) | (1,230)
Boston Properties Limited Partnership | Business Intersegment, Eliminations [Member] |  |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |  |
Net income attributable to the Company's common shareholders / unitholders | 185,715 | 145,961 | 299,097 | 346,868
Preferred Stock Dividends / Distributions | 2,625 | 2,625 | 5,250 | 5,250
Noncontrolling interest in property partnerships | 17,482 | 14,400 | 36,312 | 31,634
Interest expense | 102,357 | 92,204 | 203,366 | 182,424
Impairment loss | 0 | 0 | 22,272 | 0
Depreciation and amortization expense | 175,199 | 154,474 | 337,881 | 318,327
Transaction costs | 417 | 474 | 877 | 495
Payroll and related costs from management service contracts | 2,403 | 1,970 | 5,798 | 4,855
General and administrative expense | 35,071 | 28,468 | 76,833 | 64,362
Gains from investments in securities | 1,165 | 505 | 4,134 | 379
Interest and other income | 3,615 | 2,579 | 7,368 | 4,227
(Losses) gains on sales of real estate | 1,835 | 18,770 | 930 | 117,677
Income from unconsolidated joint ventures | 47,964 | 769 | 48,177 | 1,230
Direct reimbursement of payroll and related costs from management service contracts | 2,403 | 1,970 | 5,798 | 4,855
Company's Share of Net Operating Income | 433,454 | 379,856 | 859,433 | 751,466
Development and Management Services [Member] |  |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |  |
Payroll and related costs from management service contracts | (2,403) | (1,970) | (5,798) | (4,855)
Direct reimbursement of payroll and related costs from management service contracts | (9,986) | (9,305) | (19,263) | (17,710)
Development and Management Services [Member] | Business Intersegment, Eliminations [Member] |  |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |  |
Direct reimbursement of payroll and related costs from management service contracts | 9,986 | 9,305 | 19,263 | 17,710
Development and Management Services [Member] | Boston Properties Limited Partnership |  |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |  |
Payroll and related costs from management service contracts | (2,403) | (1,970) |  |
Direct reimbursement of payroll and related costs from management service contracts | (9,986) | (9,305) | (19,263) | (17,710)
Development and Management Services [Member] | Boston Properties Limited Partnership | Business Intersegment, Eliminations [Member] |  |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |  |
Direct reimbursement of payroll and related costs from management service contracts | 9,986 | 9,305 | 19,263 | 17,710
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 from joint ventures | 45,562 | 43,049 | 92,647 | 88,958
Noncontrolling interest - property partnerships [Member] | Business Intersegment, Eliminations [Member] |  |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |  |
Company's share of net operating from joint ventures | 45,562 | 43,049 | 92,647 | 88,958
Noncontrolling interest - property partnerships [Member] | Boston Properties Limited Partnership | Business Intersegment, Eliminations [Member] |  |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |  |
Company's share of net operating from joint ventures | 45,562 | 43,049 | 92,647 | 88,958
Unconsolidated Joint Ventures [Member] |  |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |  |
Interest expense | (20,803) | (14,708) | (41,560) | (29,132)
Company's share of net operating from joint ventures | (24,715) | (16,227) | (50,064) | (32,287)
Depreciation and amortization expense | (24,818) | (14,527) | (53,464) | (29,252)
Income from unconsolidated joint ventures | (47,964) | (769) | (48,177) | (1,230)
Unconsolidated Joint Ventures [Member] | Business Intersegment, Eliminations [Member] |  |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |  |
Company's share of net operating from joint ventures | (24,715) | (16,227) | (50,064) | (32,287)
Unconsolidated Joint Ventures [Member] | Boston Properties Limited Partnership | Business Intersegment, Eliminations [Member] |  |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |  |
Company's share of net operating from joint ventures | $ (24,715) | $ (16,227) | $ (50,064) | $ (32,287)

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