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Consolidated Statements of Capital and Noncontrolling Interests - USD ($) | 3 Months Ended | 6 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | ---
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018 | Mar. 31, 2019 | Dec. 31, 2018 | Mar. 31, 2018 | Dec. 31, 2017
Common Stock, Shares, Outstanding | 154,563,130 |  | 154,563,130 |  |  | 154,458,478 |  |
Cumulative effect of a change in accounting principle |  |  | $ (4,379,000) | $ 5,496,000 |  |  |  |
Effective portion of interest rate contracts | $ (4,426,000) |  | (7,054,000) |  |  |  |  |
Amortization of interest rate contracts | 1,666,000 | $ 1,666,000 | 3,332,000 | 3,332,000 |  |  |  |
Acquisition of noncontrolling interest in property partnerships | (187,006,000) |  | (187,006,000) |  |  |  |  |
Contributions from noncontrolling interests in property partnerships | (7,761,000) | (12,265,000) | 12,148,000 | 27,532,000 |  |  |  |
Distributions to noncontrolling interests in property partnerships | (15,273,000) | $ (13,343,000) | (39,401,000) | (44,033,000) |  |  |  |
Boston Properties Limited Partnership |  |  |  |  |  |  |  |
Redeemable Noncontrolling Interest, Equity, Preferred, Carrying Amount | 2,324,238,000 |  | 2,324,238,000 |  |  | $ 2,000,591,000 |  |
Beginning Balance |  |  | 5,912,323,000 |  |  |  |  |
Contributions from noncontrolling interests in property partnerships |  |  | 12,148,000 | $ 27,532,000 |  |  |  |
Ending Balance | $ 5,401,414,000 |  | $ 5,401,414,000 |  |  |  |  |
General Partner [Member] |  |  |  |  |  |  |  |
Common Stock, Shares, Outstanding | 1,726,000 | 1,722,000 | 1,726,000 | 1,722,000 | 1,725,000 | 1,722,000 | 1,722,000 | 1,720,000
Contributions, units | 1,000 | 0 | 3,000 | 1,000 |  |  |  |
Conversion of redeemable partnership units | 0 | 0 | 1,000 | 1,000 |  |  |  |
Limited Partner [Member] |  |  |  |  |  |  |  |
Common Stock, Shares, Outstanding | 152,837,000 | 152,689,000 | 152,837,000 | 152,689,000 | 152,790,000 | 152,736,000 | 152,640,000 | 152,606,000
Contributions, units | 26,000 | 39,000 | 67,000 | 50,000 |  |  |  |
Conversion of redeemable partnership units | 21,000 | 10,000 | 34,000 | 33,000 |  |  |  |
Partners' Capital (General and Limited Partners) [Member] |  |  |  |  |  |  |  |
Beginning Balance | $ 3,603,174,000 | $ 3,842,862,000 | $ 4,054,996,000 | $ 3,664,436,000 |  |  |  |
Cumulative effect of a change in accounting principle | 0 | 0 | (3,864,000) | 4,933,000 |  |  |  |
Contributions, value | 882,000 | 233,000 | 5,702,000 | 1,685,000 |  |  |  |
Allocated net income for the year | 166,687,000 | 131,082,000 | 268,470,000 | 314,182,000 |  |  |  |
Distributions | (146,835,000) | (123,529,000) | (293,625,000) | (249,644,000) |  |  |  |
Unearned compensation | 613,000 | 552,000 | (775,000) | (656,000) |  |  |  |
Conversion of redeemable partnership units | 720,000 | 364,000 | 1,212,000 | 1,196,000 |  |  |  |
Adjustment to reflect redeemable partnership units at redemption value | 100,174,000 | (30,791,000) | (306,701,000) | 84,641,000 |  |  |  |
Acquisition of noncontrolling interest in property partnerships | (162,505,000) |  | (162,505,000) |  |  |  |  |
Ending Balance | 3,562,910,000 | 3,820,773,000 | 3,562,910,000 | 3,820,773,000 |  |  |  |
Preferred Units [Member] |  |  |  |  |  |  |  |
Beginning Balance | 193,623,000 | 193,623,000 | 193,623,000 | 193,623,000 |  |  |  |
Allocated net income for the year | 2,625,000 | 2,625,000 | 5,250,000 | 2,625,000 |  |  |  |
Distributions | (2,625,000) | (2,625,000) | (5,250,000) | (2,625,000) |  |  |  |
Ending Balance | 193,623,000 | 193,623,000 | 193,623,000 | 193,623,000 |  |  |  |
Accumulated Other Comprehensive (Income) Loss [Member] |  |  |  |  |  |  |  |
Beginning Balance | (48,734,000) | (49,062,000) | (47,741,000) | (50,429,000) |  |  |  |
Effective portion of interest rate contracts | (3,973,000) |  | (6,332,000) |  |  |  |  |
Amortization of interest rate contracts | 1,367,000 | 1,367,000 | 2,733,000 | 2,734,000 |  |  |  |
Ending Balance | (51,340,000) | (47,695,000) | (51,340,000) | (47,695,000) |  |  |  |
Noncontrolling interest - property partnerships [Member] |  |  |  |  |  |  |  |
Beginning Balance | 1,710,608,000 | 1,685,715,000 | 1,711,445,000 | 1,683,760,000 |  |  |  |
Cumulative effect of a change in accounting principle | 0 |  | (70,000) |  |  |  |  |
Allocated net income for the year | 17,482,000 | 14,400,000 | 36,312,000 | 31,634,000 |  |  |  |
Amortization of interest rate contracts | 144,000 | 144,000 | 288,000 | 288,000 |  |  |  |
Acquisition of noncontrolling interest in property partnerships | (24,501,000) |  | (24,501,000) |  |  |  |  |
Contributions from noncontrolling interests in property partnerships | (7,761,000) | (12,265,000) | 12,148,000 | 27,532,000 |  |  |  |
Distributions to noncontrolling interests in property partnerships | (15,273,000) | (13,343,000) | 39,401,000 | (44,033,000) |  |  |  |
Ending Balance | 1,696,221,000 | 1,699,181,000 | 1,696,221,000 | 1,699,181,000 |  |  |  |
Noncontrolling interest - property partnerships [Member] | Boston Properties Limited Partnership |  |  |  |  |  |  |  |
Cumulative effect of a change in accounting principle |  |  | (70,000) |  |  |  |  |
Total Capital [Member] |  |  |  |  |  |  |  |
Beginning Balance | 5,458,671,000 | 5,673,138,000 | 5,912,323,000 | 5,491,390,000 |  |  |  |
Cumulative effect of a change in accounting principle | 0 | 0 | (3,934,000) | 4,933,000 |  |  |  |
Contributions, value | 882,000 | 233,000 | 5,702,000 | 1,685,000 |  |  |  |
Allocated net income for the year | 186,794,000 | 148,107,000 | 310,032,000 | 348,441,000 |  |  |  |
Distributions | (149,460,000) | (126,154,000) | (298,875,000) | (252,269,000) |  |  |  |
Unearned compensation | 613,000 | 552,000 | (775,000) | (656,000) |  |  |  |
Conversion of redeemable partnership units | 720,000 | 364,000 | 1,212,000 | 1,196,000 |  |  |  |
Adjustment to reflect redeemable partnership units at redemption value | 100,174,000 | (30,791,000) | (306,701,000) | 84,641,000 |  |  |  |
Effective portion of interest rate contracts | (3,973,000) |  | (6,332,000) |  |  |  |  |
Amortization of interest rate contracts | 1,511,000 | 1,511,000 | 3,021,000 | 3,022,000 |  |  |  |
Acquisition of noncontrolling interest in property partnerships | (187,006,000) |  |  |  |  |  |  |
Contributions from noncontrolling interests in property partnerships | (7,761,000) | (12,265,000) | 12,148,000 | (27,532,000) |  |  |  |
Distributions to noncontrolling interests in property partnerships | (15,273,000) | (13,343,000) | (39,401,000) | (44,033,000) |  |  |  |
Ending Balance | 5,401,414,000 | 5,665,882,000 | 5,401,414,000 | 5,665,882,000 |  |  |  |
Noncontrolling interest - Redeemable partnership units [Member] |  |  |  |  |  |  |  |
Redeemable Noncontrolling Interest, Equity, Preferred, Carrying Amount | 2,324,238,000 | 2,235,432,000 | 2,324,238,000 | 2,235,432,000 | $ 2,414,240,000 | $ 2,000,591,000 | $ 2,196,603,000 | $ 2,292,263,000
Cumulative effect of a change in accounting principle | 0 | 0 | (445,000) | 563,000 |  |  |  |
Contributions, value | 1,082,000 | 715,000 | 35,482,000 | 34,973,000 |  |  |  |
Allocated net income for the year | 19,028,000 | 14,879,000 | 30,627,000 | 35,311,000 |  |  |  |
Distributions | (17,206,000) | (14,357,000) | (34,391,000) | (28,708,000) |  |  |  |
Unearned compensation | 8,286,000 | 7,010,000 | (12,704,000) | (13,443,000) |  |  |  |
Conversion of redeemable partnership units | (720,000) | (364,000) | (1,212,000) | (1,196,000) |  |  |  |
Adjustment to reflect redeemable partnership units at redemption value | (100,174,000) | 30,791,000 | 306,701,000 | (84,641,000) |  |  |  |
Effective portion of interest rate contracts | 453,000 |  | 722,000 |  |  |  |  |
Amortization of interest rate contracts | $ 155,000 | $ 155,000 | $ 311,000 | $ 310,000 |  |  |  |

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