XML 103 R80.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Noncontrolling Interests Redeemable interest in property partnerships (narrative) (Details) - USD ($) $ in Thousands |  |  |  | 12 Months Ended
--- | --- | --- | --- | ---
Sep. 15, 2015 | Aug. 06, 2015 | Oct. 04, 2012 | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items] |  |  |  |  |  |
Payments for Repurchase of Redeemable Noncontrolling Interest |  |  |  | $ 0 | $ 0 | $ 108,499
Fountain Square |  |  |  |  |  |
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items] |  |  |  |  |  |
Aggregate purchase price |  |  | $ 385,000 |  |  |
Debt recorded upon consolidation |  |  | $ 211,300 |  |  |
Ownership Percentage | 50.00% | 50.00% | 50.00% |  |  |
Fixed Price to Acquire Remaining Portion of Joint venture |  | $ 100,900 |  |  |  |
Consideration paid |  |  | $ 87,000 |  |  |
Ownership Percentage by Parent |  |  | 50.00% |  |  |
Future Fixed Price to Acquire Remaining Portion of Joint venture |  |  | $ 102,000 |  |  |
Payments for Repurchase of Redeemable Noncontrolling Interest | $ 100,900 |  |  |  |  |
Mortgage debt assumed upon acquisition of noncontrolling interest | $ 105,600 |  |  |  |  |

X
- Definition Aggregate purchase price + References No definition available. + Details
Name: | bxp_Aggregatepurchaseprice
Namespace Prefix: | bxp_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Fixed Price to Acquire Remaining Portion of Joint venture + References No definition available. + Details
Name: | bxp_FixedPricetoAcquireRemainingPortionofJointventure
Namespace Prefix: | bxp_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Future Fixed Price to Acquire Remaining Portion of Joint venture + References No definition available. + Details
Name: | bxp_FutureFixedPricetoAcquireRemainingPortionofJointventure
Namespace Prefix: | bxp_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Mortgage debt assumed upon acquisition of noncontrolling interest + References No definition available. + Details
Name: | bxp_Mortgagedebtassumeduponacquisitionofnoncontrollinginterest
Namespace Prefix: | bxp_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of long-term debt due after one year or the normal operating cycle, if longer, assumed at the acquisition date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=73530397&loc=d3e4845-128472 + Details
Name: | us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesLongTermDebt
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
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_ConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity. + References No definition available. + Details
Name: | us-gaap_MinorityInterestOwnershipPercentageByNoncontrollingOwners
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition The parent entity's interest in net assets of the subsidiary, expressed as a percentage. + References No definition available. + Details
Name: | us-gaap_MinorityInterestOwnershipPercentageByParent
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition The cash outflow during the period for redemption of redeemable noncontrolling interests. + References No definition available. + Details
Name: | us-gaap_PaymentsForRepurchaseOfRedeemableNoncontrollingInterest
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Investing Activities -URI http://asc.fasb.org/extlink&oid=6516133 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 13 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3213-108585 + Details
Name: | us-gaap_PaymentsToAcquireBusinessesGross
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

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