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Derivative and Hedging Instruments (Details) | 12 Months Ended
--- | ---
Dec. 31, 2015 USD ($) yr swaps | Dec. 31, 2014 USD ($) | Dec. 31, 2013 USD ($)
Derivative [Line Items] |  |  |
Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months | $ (141,000) |  |
Fair Value | (10,302,000) | $ 0 | $ 0
Interest Rate Swap [Member] |  |  |
Derivative [Line Items] |  |  |
Derivative, Notional Amount | 950,000,000 |  |
Derivative, Net Liability Position, Aggregate Fair Value | 11,700,000 |  |
Assets Needed for Immediate Settlement, Aggregate Fair Value | 11,700,000 |  |
Derivative Instruments, Loss Recognized in Other Comprehensive Income (Loss), Effective Portion | 12,700,000 |  |
Derivative Instruments, Gain Recognized in Other Comprehensive Income (Loss), Effective Portion | 2,400,000 |  |
Fair Value | $ (10,302,000) |  |
Boston Properties Limited Partnership [Member] | Interest Rate Swap [Member] |  |  |
Derivative [Line Items] |  |  |
Number of interest rate swap agreements entered into | swaps | 17 |  |
Term of anticipated mortgage loan (in years) | yr | 10 |  |
Derivative, Average Fixed Interest Rate | 2.423% |  |
Derivative, Notional Amount | $ 550,000,000 |  |
Maximum period of hedging exposure to the variability in future cash flows for forecasted transactions (in years) | yr | 10 |  |
Fair Value | $ (4,231,000) |  |
767 Fifth Partners LLC [Member] |  |  |
Derivative [Line Items] |  |  |
Ownership Percentage by Parent | 60.00% |  |
767 Fifth Partners LLC [Member] | Interest Rate Swap [Member] |  |  |
Derivative [Line Items] |  |  |
Number of interest rate swap agreements entered into | swaps | 14 |  |
Term of anticipated mortgage loan (in years) | yr | 10 |  |
Derivative, Average Fixed Interest Rate | 2.646% |  |
Derivative, Notional Amount | $ 400,000,000 |  |
Maximum period of hedging exposure to the variability in future cash flows for forecasted transactions (in years) | yr | 10 |  |
Fair Value | $ (6,071,000) |  |
Boston Properties Limited Partnership [Member] |  |  |
Derivative [Line Items] |  |  |
Fair Value | $ (10,302,000) | $ 0 | $ 0

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- Definition Aggregate notional amount specified by the derivative(s). Expressed as an absolute value. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Article 12 -Section 13 -Sentence Column B + Details
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- Definition The aggregate fair value of assets needed to immediately settle the derivative instruments with credit-risk-related contingent features if the credit-risk-related contingent features were triggered at the end of the reporting period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4H -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5624258-113959 + Details
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- Definition The effective portion of gains on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=36458714&loc=SL7669646-108580 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5624171-113959 + Details
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