XML 62 R47.htm IDEA: XBRL DOCUMENT
v3.10.0.1

Stockholders' Equity / Partners' Capital Narrative (Details) |  | 9 Months Ended |  |  |
--- | --- | --- | --- | --- | ---
Jun. 02, 2017 USD ($) yr | Sep. 30, 2018 USD ($) $ / shares shares | Mar. 27, 2018 $ / shares | Dec. 31, 2017 USD ($) $ / shares shares | Jun. 03, 2014 USD ($)
Class of Stock [Line Items] |  |  |  |  |
Common stock, shares outstanding |  | 154,440,239 |  | 154,325,286 |
General Partners' Capital Account, Units Outstanding |  | 1,722,375 |  |  |
Limited Partners' Capital Account, Units Outstanding |  | 152,717,864 |  |  |
Shares of Common Stock in connection with the redemption of an equal number of OP Units (in shares) |  | 61,021 |  |  |
Common Stock, Value, Issued | $ |  | $ 1,544,000 |  | $ 1,543,000 |
ATM Program [Member] |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |
At the market stock offering program, aggregate value of common stock | $ | $ 600,000,000 |  |  |  | $ 600,000,000
At Market Stock Offering Program Maximum Length Of Sale In Years | yr | 3 |  |  |  |
Common Stock, Value, Issued | $ |  | $ 0 |  |  |
Series B Cumulative Redeemable Preferred Stock [Member] |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |
Series B, Shares Outstanding (in shares) |  | 80,000 |  | 80,000 |
Series B, Dividend Rate, Percentage |  | 5.25% |  |  |
Series B, Liquidation Preference Per Share (dollars per share) | $ / shares |  | $ 2,500.00 | $ 2,500.00 | $ 2,500 |
Ratio of depository shares to shares of Series B Preferred Stock |  | 0.01 |  |  |
Depository shares of Series B Cumulative Redeemable Preferred [Member] |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |
Series B, Shares Outstanding (in shares) |  | 8,000,000 |  |  |
Series B, Liquidation Preference Per Share (dollars per share) | $ / shares |  | $ 25.00 | $ 25.00 |  |
Boston Properties Limited Partnership |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |
General Partners' Capital Account, Units Outstanding |  | 1,722,375 |  | 1,719,540 |
Limited Partners' Capital Account, Units Outstanding |  | 152,717,864 |  | 152,605,746 |
Boston Properties Limited Partnership | Series B Cumulative Redeemable Preferred Stock [Member] |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |
Series B, Shares Outstanding (in shares) |  | 80,000 |  | 80,000 |
Series B, Liquidation Preference Per Share (dollars per share) | $ / shares |  | $ 2,500 |  | $ 2,500 |

X
- Definition At The Market Stock Offering Program, Aggregate Value Of Common Stock + References No definition available. + Details
Name: | bxp_AtMarketStockOfferingProgramAggregateValueOfCommonStock
Namespace Prefix: | bxp_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition At Market Stock Offering Program Maximum Length Of Sale In Years + References No definition available. + Details
Name: | bxp_AtMarketStockOfferingProgramMaximumLengthOfSaleInYears
Namespace Prefix: | bxp_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Ratio of depository shares to shares of Series B Preferred Stock + References No definition available. + Details
Name: | bxp_RatioOfDepositorySharesToSharesOfSeriesBPreferredStock
Namespace Prefix: | bxp_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | instant

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_ClassOfStockLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(29)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=84159872&loc=d3e21463-112644 + Details
Name: | us-gaap_CommonStockSharesOutstanding
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition Aggregate par or stated value of issued nonredeemable common stock (or common stock redeemable solely at the option of the issuer). This item includes treasury stock repurchased by the entity. Note: elements for number of nonredeemable common shares, par value and other disclosure concepts are in another section within stockholders' equity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(29)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_CommonStockValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The number of new shares issued in the conversion of stock in a noncash (or part noncash) transaction. Noncash is defined as transactions during a period that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4313-108586 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4332-108586 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4304-108586 + Details
Name: | us-gaap_ConversionOfStockSharesIssued1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition The number of general partner units outstanding. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 5 -Subparagraph (SAB Topic 4.F) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187171-122770 + Details
Name: | us-gaap_GeneralPartnersCapitalAccountUnitsOutstanding
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition The number of limited partner units outstanding. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 272 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6373374&loc=d3e70434-108055 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 5 -Subparagraph (SAB Topic 4.F) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187171-122770 + Details
Name: | us-gaap_LimitedPartnersCapitalAccountUnitsOutstanding
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition The percentage rate used to calculate dividend payments on preferred stock. + References No definition available. + Details
Name: | us-gaap_PreferredStockDividendRatePercentage
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition The per share liquidation preference (or restrictions) of nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) that has a preference in involuntary liquidation considerably in excess of the par or stated value of the shares. The liquidation preference is the difference between the preference in liquidation and the par or stated values of the share. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=84159872&loc=d3e21475-112644 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=84159872&loc=d3e21484-112644 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(28)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08(d)(1)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(d)(1)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 + Details
Name: | us-gaap_PreferredStockLiquidationPreference
Namespace Prefix: | us-gaap_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | instant

X
- Definition Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(28)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_PreferredStockSharesOutstanding
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Details
Name: | us-gaap_StatementEquityComponentsAxis=bxp_AtmProgramMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementClassOfStockAxis=bxp_SeriesBCumulativeRedeemablePreferredStockUnitMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementClassOfStockAxis=bxp_DepositorySharesOfSeriesBCumulativeRedeemablePreferredMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ConsolidatedEntitiesAxis=us-gaap_SubsidiariesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |