XML 117 R96.htm IDEA: XBRL DOCUMENT
v3.6.0.2

Stock Option and Incentive Plan (Narrative) (Details) |  |  |  |  | 12 Months Ended |
--- | --- | --- | --- | --- | --- | ---
Feb. 04, 2016 USD ($) shares | Jan. 25, 2016 USD ($) yr indices tiers | Feb. 06, 2015 USD ($) shares | May 15, 2012 yr shares | Dec. 31, 2014 USD ($) | Mar. 11, 2013 USD ($)
MYLTIP 2013 |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Value of MYLTIP Awards | $ 13,500,000 |  |  |  |  |
MYLTIP Units forfeited | shares | 205,762 |  |  |  |  |
Final awards percentage of target | 109.50% |  |  |  |  |
OPP Units 2012 [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Potential Awards Earned |  |  | $ 40,000,000 |  |  |
Outperformance awards earned |  |  | $ 32,100,000 |  |  |
Potential maximum amount of Outperformance Awards earned (percent) |  |  | 80.00% |  |  |
2012 OPP Units forfeited | shares |  |  | 174,549 |  |  |
2012 Stock Option and Incentive Plan [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Number of Additional Shares Authorized | shares |  |  |  | 13,000,000 |  |
Other Than Stock Options Awards Conversion Ratio |  |  |  | 2.32 |  |
Stock Option Awards Conversion Ratio |  |  |  | 1.0 |  |
Stock Option and Incentive Plan Term Period | yr |  |  |  | 10 |  |
MYLTIP 2016 [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Number of Tiers | tiers |  | 3 |  |  |  |
TSR measurement (in years) | yr |  | 3 |  |  |  |
Distributions percent before measurement date |  | 10.00% |  |  |  |
Indices Used to Compare TSR | indices |  | 2 |  |  |  |
Threshold Tier |  | $ 9,900,000 |  |  |  |
Target Tier |  | 19,700,000 |  |  |  |
High Tier |  | $ 49,300,000 |  |  |  |
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% |  |  |  |
Value of MYLTIP Awards |  | $ 17,300,000 |  |  |  |
MYLTIP Value Amortized Into Earnings, Years | yr |  | 4 |  |  |  |
Minimum [Member] | MYLTIP 2016 [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Potential Awards Earned |  | $ 0 |  |  |  |
Maximum [Member] | MYLTIP 2016 [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Potential Awards Earned |  | $ 49,300,000 |  |  |  |
Board of Directors Chairman [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Cash Payment Related to Transition Agreement |  |  |  |  |  | $ 6,700,000
Target Equity Award Compensation Associated with Transition Agreement |  |  |  |  |  | $ 11,100,000
Compensation Expense associated with Transition Agreement |  |  |  |  | $ 3,900,000 |
Cohen & Steers Realty Majors Portfolio Index [Member] | MYLTIP 2016 [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Weighted Percentage of Index Used to Compare to TSR |  | 50.00% |  |  |  |
NAREIT Office Index adjusted [Member] | MYLTIP 2016 [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Weighted Percentage of Index Used to Compare to TSR |  | 50.00% |  |  |  |
MYLTIP vesting 2019 [Member] | MYLTIP 2016 [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Vesting Percentage |  | 50.00% |  |  |  |
MYLTIP vesting 2020 [Member] | MYLTIP 2016 [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Vesting Percentage |  | 50.00% |  |  |  |

X
- Definition Cash Payment Related to Transition Agreement + References No definition available. + Details
Name: | bxp_CashPaymentRelatedToTransitionAgreement
Namespace Prefix: | bxp_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Compensation Expense associated with Transition Agreement + References No definition available. + Details
Name: | bxp_CompensationExpenseAssociatedWithTransitionAgreement
Namespace Prefix: | bxp_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Distributions Percent Before Measurement Date + References No definition available. + Details
Name: | bxp_DistributionsPercentBeforeMeasurementDate
Namespace Prefix: | bxp_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Final awards percentage of target + References No definition available. + Details
Name: | bxp_Finalawardspercentageoftarget
Namespace Prefix: | bxp_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition High Tier + References No definition available. + Details
Name: | bxp_HighTier
Namespace Prefix: | bxp_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Indices Used to Compare TSR + References No definition available. + Details
Name: | bxp_IndicesUsedtoCompareTSR
Namespace Prefix: | bxp_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition MYLTIP Units Forfeited + References No definition available. + Details
Name: | bxp_MYLTIPUnitsForfeited
Namespace Prefix: | bxp_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition MYLTIP Value Amortized Into Earnings, Years + References No definition available. + Details
Name: | bxp_MyltipValueAmortizedIntoEarningsYears
Namespace Prefix: | bxp_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of Tiers + References No definition available. + Details
Name: | bxp_NumberOfTiers
Namespace Prefix: | bxp_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Other Than Stock Options Awards Conversion Ratio + References No definition available. + Details
Name: | bxp_OtherThanStockOptionsAwardsConversionRatio
Namespace Prefix: | bxp_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | duration

X
- Definition Outperformance awards earned + References No definition available. + Details
Name: | bxp_Outperformanceawardsearned
Namespace Prefix: | bxp_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Percentage to Cause Some Awards to be Earned Even if on a Relative Basis it Would Not Result in any Earned Awards + References No definition available. + Details
Name: | bxp_PercentageToCauseSomeAwardsToBeEarnedEvenIfOnRelativeBasisItWouldNotResultInAnyEarnedAwards
Namespace Prefix: | bxp_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage of annualized TSR for Reduction of Earned Awards + References No definition available. + Details
Name: | bxp_PercentageofannualizedTSRforReductionofEarnedAwards
Namespace Prefix: | bxp_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Potential Awards Earned + References No definition available. + Details
Name: | bxp_PotentialAwardsEarned
Namespace Prefix: | bxp_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Potential maximum amount of Outperformance Awards earned (percent) + References No definition available. + Details
Name: | bxp_PotentialmaximumamountofOutperformanceAwardsearnedpercent
Namespace Prefix: | bxp_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Stock Option and Incentive Plan Term Period + References No definition available. + Details
Name: | bxp_StockOptionAndIncentivePlanTermPeriod
Namespace Prefix: | bxp_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Stock Option Awards Conversion Ratio + References No definition available. + Details
Name: | bxp_StockOptionAwardsConversionRatio
Namespace Prefix: | bxp_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | duration

X
- Definition TSR Measurement, Years. + References No definition available. + Details
Name: | bxp_TSRMeasurementYears
Namespace Prefix: | bxp_
Data Type: | xbrli:positiveIntegerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Target Equity Award Compensation Associated with Transition Agreement + References No definition available. + Details
Name: | bxp_TargetEquityAwardCompensationAssociatedWithTransitionAgreement
Namespace Prefix: | bxp_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Target Tier + References No definition available. + Details
Name: | bxp_TargetTier
Namespace Prefix: | bxp_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Threshold Tier + References No definition available. + Details
Name: | bxp_ThresholdTier
Namespace Prefix: | bxp_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition 2012 OPP Unit forfeited + References No definition available. + Details
Name: | bxp_TwoThousandTwelveOPPUnitsForfeited
Namespace Prefix: | bxp_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Value of MYLTIP Awards + References No definition available. + Details
Name: | bxp_ValueOfMyltipAwards
Namespace Prefix: | bxp_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Vesting percentage + References No definition available. + Details
Name: | bxp_VestingPercentage
Namespace Prefix: | bxp_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Weighted Percentage of Index Used to Compare to TSR + References No definition available. + Details
Name: | bxp_WeightedPercentageofIndexUsedtoComparetoTSR
Namespace Prefix: | bxp_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of additional shares authorized for issuance under an established share-based compensation plan. + References No definition available. + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfAdditionalSharesAuthorized
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | bxp_StockOptionAndIncentivePlanAndStockRepurchasePlanAxis=bxp_MYLTIPtwothousandthirteenMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | bxp_StockOptionAndIncentivePlanAndStockRepurchasePlanAxis=bxp_OppUnitsTwoThousandAndTwelveMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | bxp_StockOptionAndIncentivePlanAndStockRepurchasePlanAxis=bxp_TwoThousandTwelveStockOptionAndIncentivePlanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | bxp_StockOptionAndIncentivePlanAndStockRepurchasePlanAxis=bxp_MYLTIPTwothousandsixteenMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RangeAxis=us-gaap_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RangeAxis=us-gaap_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_TitleOfIndividualAxis=us-gaap_BoardOfDirectorsChairmanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | bxp_PerformanceIndexAxis=bxp_CohenSteersRealtyMajorsPortfolioIndexMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | bxp_PerformanceIndexAxis=bxp_NareitOfficeIndexAdjustedMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | bxp_VestingPeriodAxis=bxp_MYLTIPvesting2019Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | bxp_VestingPeriodAxis=bxp_MYLTIPvestingtwothousandtwentyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |