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Noncontrolling Interests (Narrative) (Details) | Dec. 31, 2017 shares
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Noncontrolling Interest [Member] |
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items] |
Operating Partnership (OP) Units (in shares) | 16,810,378
Boston Properties Limited Partnership | Noncontrolling Interest [Member] |
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items] |
Long-Term Incentive Plan (LTIP) Units (in shares) | 818,343.000
Boston Properties Limited Partnership | OPP Units 2012 [Member] |
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items] |
Outperformance awards in LTIP Units (in shares) | 118,067
Boston Properties Limited Partnership | MYLTIP 2013 |
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items] |
2013 MYLTIP | 85,405
Boston Properties Limited Partnership | MYLTIP 2014 |
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items] |
2014 MYLTIP | 25,107
Boston Properties Limited Partnership | MYLTIP 2015 [Member] |
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items] |
2015 MYLTIP | 366,618
Boston Properties Limited Partnership | MYLTIP 2016 [Member] |
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items] |
2016 MYLTIP | 473,360
Boston Properties Limited Partnership | MYLTIP 2017 [Member] |
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items] |
2017 MYLTIP | 400,000

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- Definition 2013 MYLTIP + References No definition available. + Details
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