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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, 2019 | Sep. 30, 2018 | Sep. 30, 2019 | Sep. 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 | $ 107,771 | $ 119,118 | $ 370,200 | $ 423,835
Preferred Stock Dividends / Distributions | (2,625) | (2,625) | (7,875) | (7,875)
Noncontrolling interest-common units of the Operating Partnership | (12,504) | (13,852) | (43,133) | (49,128)
Noncontrolling interest in property partnerships | (18,470) | (14,850) | (54,782) | (46,484)
Interest expense | (106,471) | (95,366) | (309,837) | (277,790)
Loss from early extinguishment of debt | 28,010 | 0 | 28,010 | 0
Company's share of net operating income from joint ventures | (456,475) | (411,698) | (1,358,491) | (1,219,835)
Depreciation and amortization expense | (165,862) | (157,996) | (507,867) | (480,210)
Transaction costs | (538) | (914) | (1,415) | (1,409)
General and administrative expense | (31,147) | (29,677) | (107,980) | (94,039)
Gains from investments in securities | (106) | (1,075) | (4,240) | (1,454)
Interest and other income | (7,178) | (2,822) | (14,546) | (7,049)
Income (loss) from unconsolidated joint ventures | 649 | 4,313 | (47,528) | 3,083
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 | 107,771 | 119,118 | 370,200 | 423,835
Preferred Stock Dividends / Distributions | 2,625 | 2,625 | 7,875 | 7,875
Noncontrolling interest-common units of the Operating Partnership | 12,504 | 13,852 | 43,133 | 49,128
Noncontrolling interest in property partnerships | 18,470 | 14,850 | 54,782 | 46,484
Interest expense | 106,471 | 95,366 | 309,837 | 277,790
Loss from early extinguishment of debt | (28,010) | 0 | (28,010) | 0
Impairment loss | 0 | 0 | 24,038 | 0
Depreciation and amortization expense | 165,862 | 157,996 | 507,867 | 480,210
Transaction costs | 538 | 914 | 1,415 | 1,409
Payroll and related costs from management service contracts | 2,429 | 2,516 | 8,227 | 7,371
General and administrative expense | 31,147 | 29,677 | 107,980 | 94,039
Gains from investments in securities | 106 | 1,075 | 4,240 | 1,454
Interest and other income | 7,178 | 2,822 | 14,546 | 7,049
Gains (losses) on sales of real estate | (15) | 7,863 | 766 | 122,552
Income (loss) from unconsolidated joint ventures | (649) | (4,313) | 47,528 | (3,083)
Direct reimbursement of payroll and related costs from management service contracts | 2,429 | 2,516 | 8,227 | 7,371
Company's Share of Net Operating Income | 433,291 | 391,141 | 1,292,724 | 1,142,607
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 | 122,117 | 136,201 | 421,214 | 483,069
Preferred Stock Dividends / Distributions | (2,625) | (2,625) | (7,875) | (7,875)
Noncontrolling interest in property partnerships | (18,470) | (14,850) | (54,782) | (46,484)
Interest expense | (106,471) | (95,366) | (309,837) | (277,790)
Loss from early extinguishment of debt | 28,010 | 0 | 28,010 | 0
Depreciation and amortization expense | (164,020) | (156,056) | (501,901) | (474,383)
Transaction costs | (538) | (914) | (1,415) | (1,409)
General and administrative expense | (31,147) | (29,677) | (107,980) | (94,039)
Gains from investments in securities | (106) | (1,075) | (4,240) | (1,454)
Interest and other income | (7,178) | (2,822) | (14,546) | (7,049)
Income (loss) from unconsolidated joint ventures | 649 | 4,313 | (47,528) | 3,083
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 | 122,117 | 136,201 | 421,214 | 483,069
Preferred Stock Dividends / Distributions | 2,625 | 2,625 | 7,875 | 7,875
Noncontrolling interest in property partnerships | 18,470 | 14,850 | 54,782 | 46,484
Interest expense | 106,471 | 95,366 | 309,837 | 277,790
Loss from early extinguishment of debt | 28,010 | 0 | 28,010 | 0
Impairment loss | 0 | 0 | 22,272 | 0
Depreciation and amortization expense | 164,020 | 156,056 | 501,901 | 474,383
Transaction costs | 538 | 914 | 1,415 | 1,409
Payroll and related costs from management service contracts | 2,429 | 2,516 | 8,227 | 7,371
General and administrative expense | 31,147 | 29,677 | 107,980 | 94,039
Gains from investments in securities | 106 | 1,075 | 4,240 | 1,454
Interest and other income | 7,178 | 2,822 | 14,546 | 7,049
Gains (losses) on sales of real estate | (15) | 9,154 | 915 | 126,831
Income (loss) from unconsolidated joint ventures | (649) | (4,313) | 47,528 | (3,083)
Direct reimbursement of payroll and related costs from management service contracts | 2,429 | 2,516 | 8,227 | 7,371
Company's Share of Net Operating Income | 433,291 | 391,141 | 1,292,724 | 1,142,607
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 | (2,429) | (2,516) | (8,227) | (7,371)
Direct reimbursement of payroll and related costs from management service contracts | (10,303) | (15,253) | (29,566) | (32,963)
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 | 10,303 | 15,253 | 29,566 | 32,963
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 | (2,429) | (2,516) | (8,227) | (7,371)
Direct reimbursement of payroll and related costs from management service contracts | (10,303) | (15,253) | (29,566) | (32,963)
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 | 10,303 | 15,253 | 29,566 | 32,963
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 | 46,249 | 43,068 | 138,896 | 132,026
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 income from joint ventures | 46,249 | 43,068 | 138,896 | 132,026
Unconsolidated Joint Ventures [Member] |  |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |  |
Interest expense | (20,483) | (19,861) | (62,043) | (48,993)
Company's share of net operating income from joint ventures | (23,065) | (22,511) | (73,129) | (54,798)
Depreciation and amortization expense | (23,477) | (44,993) | (76,941) | (74,245)
Income (loss) from unconsolidated joint ventures | 649 | 4,313 | (47,528) | 3,083
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 income from joint ventures | $ (23,065) | $ (22,511) | $ (73,129) | $ (54,798)

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