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Unsecured Senior Notes Schedule of Unsecured Senior Notes (Details) - USD ($) $ in Thousands | 12 Months Ended |  |  |
--- | --- | --- | --- | ---
Dec. 31, 2017 | Dec. 04, 2017 | Dec. 31, 2016 | Aug. 17, 2016
Debt Instrument [Line Items] |  |  |  |  |  |
Deferred finance costs, net |  | $ (34,680) |  |  |  |
Total |  | 7,247,330 |  |  | $ 7,245,953 |
Boston Properties Limited Partnership |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Deferred finance costs, net |  | (34,700) |  |  |  |
Total |  | 7,247,330 |  |  | $ 7,245,953 |
Boston Properties Limited Partnership | Senior Notes [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Principal Amount |  | 7,300,000 |  |  |  |
Net unamortized discount |  | (17,894) |  |  |  |
Deferred finance costs, net |  | (34,776) |  |  |  |
Total |  | $ 7,247,330 |  |  |  |
Boston Properties Limited Partnership | Senior Notes [Member] | Unsecured Senior Notes 5.967% |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Coupon/Stated Rate |  | 5.875% |  |  |  |
Effective Rate | [1] | 5.967% |  |  |  |
Principal Amount |  | $ 700,000 |  |  |  |
Maturity date | [2] | Oct. 15, 2019 |  |  |  |
Boston Properties Limited Partnership | Senior Notes [Member] | Unsecured Senior Notes 5.708% |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Coupon/Stated Rate |  | 5.625% |  |  |  |
Effective Rate | [1] | 5.708% |  |  |  |
Principal Amount |  | $ 700,000 |  |  |  |
Maturity date | [2] | Nov. 15, 2020 |  |  |  |
Boston Properties Limited Partnership | Senior Notes [Member] | Unsecured Senior Notes 4.289% |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Coupon/Stated Rate |  | 4.125% |  |  |  |
Effective Rate | [1] | 4.289% |  |  |  |
Principal Amount |  | $ 850,000 |  |  |  |
Maturity date | [2] | May 15, 2021 |  |  |  |
Boston Properties Limited Partnership | Senior Notes [Member] | Unsecured Senior Notes 3.954% |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Coupon/Stated Rate |  | 3.85% |  |  |  |
Effective Rate | [1] | 3.954% |  |  |  |
Principal Amount |  | $ 1,000,000 |  |  |  |
Maturity date | [2] | Feb. 01, 2023 |  |  |  |
Boston Properties Limited Partnership | Senior Notes [Member] | Unsecured Senior Notes 3.279% |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Coupon/Stated Rate |  | 3.125% |  |  |  |
Effective Rate | [1] | 3.279% |  |  |  |
Principal Amount |  | $ 500,000 |  |  |  |
Maturity date | [2] | Sep. 01, 2023 |  |  |  |
Boston Properties Limited Partnership | Senior Notes [Member] | Unsecured Senior Notes 3.916% |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Coupon/Stated Rate |  | 3.80% |  |  |  |
Effective Rate | [1] | 3.916% |  |  |  |
Principal Amount |  | $ 700,000 |  |  |  |
Maturity date | [2] | Feb. 01, 2024 |  |  |  |
Boston Properties Limited Partnership | Senior Notes [Member] | Unsecured Senior Notes 3.35% [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Coupon/Stated Rate |  | 3.20% |  | 3.20% |  |
Effective Rate |  | 3.35% | [1] | 3.35% |  |
Principal Amount |  | $ 850,000 |  |  |  |
Maturity date | [2] | Jan. 15, 2025 |  |  |  |
Boston Properties Limited Partnership | Senior Notes [Member] | Unsecured Senior Note 3.766% |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Coupon/Stated Rate |  | 3.65% |  |  |  |
Effective Rate | [1] | 3.766% |  |  |  |
Principal Amount |  | $ 1,000,000 |  |  |  |
Maturity date | [2] | Feb. 01, 2026 |  |  |  |
Boston Properties Limited Partnership | Senior Notes [Member] | Unsecured Senior Note 3.495% |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Coupon/Stated Rate |  | 2.75% |  |  |  | 2.75%
Effective Rate | [1] | 3.495% |  |  |  |
Principal Amount |  | $ 1,000,000 |  |  |  |
Maturity date | [2] | Oct. 01, 2026 |  |  |  |
[1] | Yield on issuance date including the effects of discounts on the notes, settlements of interest rate contracts and the amortization of financing costs.
[2] | No principal amounts are due prior to maturity.

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