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Earnings Per Share / Common Unit (Details) - USD ($) $ / shares in Units, $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Basic Earnings: |  |  |
Net income attributable to the company's common shareholders / unitholders | $ 862,227 | $ 511,034 | $ 572,347
Net income attributable to the company's common shareholders / unitholders (in shares / units) | 155,432,000 | 154,582,000 | 154,427,000
Net income attributable to the company's common shareholders / unitholders (in dollars per share / unit) | $ 5.55 | $ 3.31 | $ 3.71
Allocation of undistributed earnings to participating securities | $ (748) |  | $ (101)
Allocation of undistributed earnings to participating securities (in shares / units) | 0 |  | 0
Allocation of undistributed earnings to participating securities (in dollars per share / unit) | $ (0.01) |  | $ 0
Net Income Available To Common Stockholders After Allocation of Undistributed Earnings to Participating Securities Basic | $ 861,479 |  | $ 572,246
Weighted Average Number Of Shares Outstanding After Allocation of Undistributed Earnings to Participating Securities Basic (in shares) | 155,432,000 |  | 154,427,000
Earnings Per Share After Allccation of Undistributed Earnings to Particiapting Securities Basic (dollars per share) | $ 5.54 |  | $ 3.71
Effect of Dilutive Securities: |  |  |
Stock Based Compensation | $ 0 | $ 0 | $ 0
Stock Based Compensation (in shares / units) | 85,000 | 301,000 | 255,000
Weighted Average Number Diluted Shares Outstanding Adjustment (per share) | $ 0 | $ (0.01) | $ (0.01)
Diluted Earnings: |  |  |
Diluted Earnings: Net income attributable to the Company's common shareholders / unitholders | $ 861,479 | $ 511,034 | $ 572,246
Diluted Earnings: Net income attributable to the Company's common shareholders / unitholders (in shares / units) | 155,517,000 | 154,883,000 | 154,682,000
Diluted Earnings: Net income, Per Share Amount (in dollars per share / unit) | $ 5.54 | $ 3.30 | $ 3.70
Boston Properties Limited Partnership |  |  |
Redeemable Common Units | 17,211,000 | 17,618,000 | 17,485,000
Basic Earnings: |  |  |
Net income attributable to the company's common shareholders / unitholders | $ 979,979 | $ 580,102 | $ 656,903
Net income attributable to the company's common shareholders / unitholders (in shares / units) | 172,643,000 | 172,200,000 | 171,912,000
Net income attributable to the company's common shareholders / unitholders (in dollars per share / unit) | $ 5.68 | $ 3.37 | $ 3.82
Allocation of undistributed earnings to participating securities | $ (830) |  | $ (113)
Allocation of undistributed earnings to participating securities (in shares / units) | 0 |  | 0
Allocation of undistributed earnings to participating securities (in dollars per share / unit) | $ (0.01) |  | $ 0
Net Income Available To Common Stockholders After Allocation of Undistributed Earnings to Participating Securities Basic | $ 979,149 |  | $ 656,790
Weighted Average Number Of Shares Outstanding After Allocation of Undistributed Earnings to Participating Securities Basic (in shares) | 172,643,000 |  | 171,912,000
Earnings Per Share After Allccation of Undistributed Earnings to Particiapting Securities Basic (dollars per share) | $ 5.67 |  | $ 3.82
Effect of Dilutive Securities: |  |  |
Stock Based Compensation | $ 0 | $ 0 | $ 0
Stock Based Compensation (in shares / units) | 85,000 | 301,000 | 255,000
Weighted Average Number Diluted Shares Outstanding Adjustment (per share) | $ 0 | $ (0.01) | $ (0.01)
Diluted Earnings: |  |  |
Diluted Earnings: Net income attributable to the Company's common shareholders / unitholders | $ 979,149 | $ 580,102 | $ 656,790
Diluted Earnings: Net income attributable to the Company's common shareholders / unitholders (in shares / units) | 172,728,000 | 172,501,000 | 172,167,000
Diluted Earnings: Net income, Per Share Amount (in dollars per share / unit) | $ 5.67 | $ 3.36 | $ 3.81

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