XML 123 R102.htm IDEA: XBRL DOCUMENT
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Subsequent Events subsequent Events (Details) |  |  |  |  |  | 3 Months Ended | 12 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Feb. 04, 2016 USD ($) | Feb. 03, 2016 USD ($) ft² | Jan. 25, 2016 USD ($) yr tiers indices | Jan. 20, 2016 USD ($) | Jan. 06, 2016 USD ($) yr swaps | Dec. 31, 2015 USD ($) shares | Sep. 30, 2015 USD ($) | Jun. 30, 2015 USD ($) | Mar. 31, 2015 USD ($) | Dec. 31, 2014 USD ($) shares | Sep. 30, 2014 USD ($) | Jun. 30, 2014 USD ($) | Mar. 31, 2014 USD ($) | Dec. 31, 2015 USD ($) yr swaps shares | Dec. 31, 2014 USD ($) shares | Dec. 31, 2013 USD ($) | Feb. 08, 2016 shares | Feb. 01, 2016 USD ($) ft² | May. 20, 2014 shares
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock, shares issued | shares |  |  |  |  |  | 153,658,866 |  |  |  | 153,192,845 |  |  |  | 153,658,866 | 153,192,845 |  |  |  | 7,542
Proceeds from unsecured senior notes |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 0 | $ 0 | $ 1,194,753,000 |  |  |
Repayments of Unsecured Debt |  |  |  |  |  |  |  |  |  |  |  |  |  | 0 | 548,016,000 | 0 |  |  |
Revenue from a terminated tenant |  |  |  |  |  | $ 624,240,000 | $ 629,884,000 | $ 618,221,000 | $ 618,476,000 | $ 613,707,000 | $ 618,803,000 | $ 589,794,000 | $ 574,694,000 | $ 2,490,821,000 | 2,396,998,000 | 2,135,539,000 |  |  |
Subsequent Event [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
LTIP units issued (in shares) | shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 139,435 |  |
Subsequent Event [Member] | MYLTIP 2016 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Indices Used to Compare TSR | indices |  |  | 2 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of Tiers | tiers |  |  | 3 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage of annualized TSR for Reduction of Earned Awards |  |  | 0.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage to Cause Some Awards to be Earned Even if on a Relative Basis it Would Not Result in any Earned Awards |  |  | 12.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Distributions percent before measurement date |  |  | 10.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Value of MYLTIP Awards |  |  | $ 17,300,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
MYLTIP Value Amortized Into Earnings, Years | yr |  |  | 4 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
TSR measurement (in years) | yr |  |  | 3 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Member] | MYLTIP 2016 [Member] | Cohen & Steers Realty Majors Portfolio Index [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Weighted Percentage of Index Used to Compare to TSR |  |  | 50.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Member] | MYLTIP 2016 [Member] | NAREIT Office Index adjusted [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Weighted Percentage of Index Used to Compare to TSR |  |  | 50.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Member] | MYLTIP 2013 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Final awards percentage of target | 109.50% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Value of MYLTIP Awards | $ 13,500,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
TSR performance on an annualized compounded basis | 8.50% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Member] | MYLTIP 2013 [Member] | Cohen & Steers Realty Majors Portfolio Index [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
TSR performance on an annualized compounded basis | 9.40% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Member] | MYLTIP 2013 [Member] | NAREIT Office Index adjusted [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
TSR performance on an annualized compounded basis | 6.20% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Member] | High [Member] | MYLTIP 2016 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Amount of Each Tier |  |  | $ 49,300,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Member] | Minimum [Member] | MYLTIP 2016 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Potential Awards Earned |  |  | 0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Member] | Maximum [Member] | MYLTIP 2016 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Potential Awards Earned |  |  | 49,300,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Member] | Threshold [Member] | MYLTIP 2016 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Amount of Each Tier |  |  | 9,900,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Member] | Target [Member] | MYLTIP 2016 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Amount of Each Tier |  |  | $ 19,700,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Member] | MYLTIP vesting 2019 | MYLTIP 2016 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Vesting Percentage |  |  | 50.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Member] | MYLTIP vesting 2020 | MYLTIP 2016 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Vesting Percentage |  |  | 50.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Member] | Restricted Stock [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock, shares issued | shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 18,521 |  |
415 Main Street | Subsequent Event [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Sale Price Of Sold Property |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 105,400,000 |
Net Rentable Area | ft² |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 231,000 |
767 Fifth Partners LLC [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ownership Percentage by Parent |  |  |  |  |  | 60.00% |  |  |  |  |  |  |  | 60.00% |  |  |  |  |
767 Fifth Partners LLC [Member] | Subsequent Event [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ownership Percentage by Parent |  |  |  |  | 60.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest Rate Swap [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Derivative, Notional Amount |  |  |  |  |  | $ 950,000,000 |  |  |  |  |  |  |  | $ 950,000,000 |  |  |  |  |
Interest Rate Swap [Member] | 767 Fifth Partners LLC [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of interest rate swap agreements entered into | swaps |  |  |  |  |  |  |  |  |  |  |  |  |  | 14 |  |  |  |  |
Maximum period of hedging exposure to the variability in future cash flows for forecasted transactions (in years) | yr |  |  |  |  |  |  |  |  |  |  |  |  |  | 10 |  |  |  |  |
Derivative, Average Fixed Interest Rate |  |  |  |  |  | 2.646% |  |  |  |  |  |  |  | 2.646% |  |  |  |  |
Derivative, Notional Amount |  |  |  |  |  | $ 400,000,000 |  |  |  |  |  |  |  | $ 400,000,000 |  |  |  |  |
Interest Rate Swap [Member] | 767 Fifth Partners LLC [Member] | Subsequent Event [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of interest rate swap agreements entered into | swaps |  |  |  |  | 2 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Maximum period of hedging exposure to the variability in future cash flows for forecasted transactions (in years) | yr |  |  |  |  | 10 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Derivative, Average Fixed Interest Rate |  |  |  |  | 2.403% |  |  |  |  |  |  |  |  |  |  |  |  |  |
Derivative, Notional Amount |  |  |  |  | $ 50,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Boston Properties Limited Partnership [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from unsecured senior notes |  |  |  |  |  |  |  |  |  |  |  |  |  | 0 | 0 | 1,194,753,000 |  |  |
Repayments of Unsecured Debt |  |  |  |  |  |  |  |  |  |  |  |  |  | 0 | 548,016,000 | 0 |  |  |
Revenue from a terminated tenant |  |  |  |  |  | 624,240,000 | $ 629,884,000 | $ 618,221,000 | $ 618,476,000 | $ 613,707,000 | $ 618,803,000 | $ 589,794,000 | $ 574,694,000 | 2,490,821,000 | $ 2,396,998,000 | $ 2,135,539,000 |  |  |
Senior Notes [Member] | Boston Properties Limited Partnership [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Principal Amount |  |  |  |  |  | $ 5,300,000,000 |  |  |  |  |  |  |  | $ 5,300,000,000 |  |  |  |  |
Senior Notes [Member] | Unsecured senior note 3.766% [Member] | Boston Properties Limited Partnership [Member] | Subsequent Event [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Coupon/Stated Rate |  |  |  | 3.65% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from unsecured senior notes |  |  |  | $ 988,900,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Principal Amount |  |  |  | $ 1,000,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Senior Notes Pricing |  |  |  | 99.708% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Effective Rate |  |  |  | 3.766% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Terminated lease at 250 West 55th Street in NYC [Member] | Subsequent Event [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net Rentable Area | ft² |  | 85,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Revenue from a terminated tenant |  | $ 45,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |

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