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Derivative Instruments and Hedging Activities (Details) $ in Thousands |  | 3 Months Ended | 12 Months Ended |
--- | --- | --- | --- | ---
Aug. 17, 2016 USD ($) yr | Mar. 31, 2017 USD ($) yr swaps | Mar. 31, 2016 USD ($) yr swaps | Dec. 31, 2015 USD ($) swaps | Dec. 31, 2016 USD ($)
Debt Instrument [Line Items] |  |  |  |  |
Cash payment to settle interest rate swap contracts |  | $ (7,090) | $ (33,319) |  |
Boston Properties Limited Partnership | Interest Rate Swap [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Number of interest rate swap agreements entered into (swap contracts) | swaps |  |  |  | 17 |
Term of anticipated mortgage loan (in years) | yr | 10 |  |  |  |
Maximum period of hedging exposure to the variability in future cash flows for forecasted transactions (in years) | yr | 10 |  |  |  |
Average Fixed Interest Rate |  |  |  | 2.423% |
Notional Amount |  |  |  | $ 550,000 |
Cash payment to settle interest rate swap contracts | $ 49,300 |  |  |  |
Losses from interest rate contracts | 100 |  |  |  |
Derivative Instruments, Loss Reclassified from Accumulated OCI into Income, Effective Portion | 49,200 |  |  |  |
Derivative Instruments Loss Reclassified From Accumulated OCI Into Income Effective yearly amount | $ 4,900 |  |  |  |
767 Fifth Partners LLC [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Ownership Percentage by the Company |  | 60.00% |  |  |
767 Fifth Partners LLC [Member] | Interest Rate Swap [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Number of interest rate swap agreements entered into (swap contracts) | swaps |  | 16 | 2 |  |
Term of anticipated mortgage loan (in years) | yr |  | 10 |  |  |
Maximum period of hedging exposure to the variability in future cash flows for forecasted transactions (in years) | yr |  | 10 | 10 |  |
Derivative, Net Liability Position, Aggregate Fair Value |  | $ 8,600 |  |  |
Assets Needed for Immediate Settlement, Aggregate Fair Value |  | 8,600 |  |  |
Amount of loss related to the effective portion recognized in Other Liabilities |  | 8,600 |  |  |
Derivative Instruments, Gain Recognized in Prepaid Expenses and Other Assets |  | $ 600 |  |  |
Average Fixed Interest Rate |  | 2.619% |  |  |
Notional Amount |  | $ 450,000 | $ 50,000 |  | $ 450,000
Estimated current balance held in Accumulated Other Comprehensive Loss to be reclassified into earnings within the next twelve months |  | (700) |  |  |
Unsecured Debt [Member] | Boston Properties Limited Partnership |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Coupon/Stated Rate | 2.75% |  |  |  |
Boston Properties Limited Partnership |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Cash payment to settle interest rate swap contracts |  | $ (7,090) | $ (33,319) |  |

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