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Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands | Dec. 31, 2018 | Dec. 31, 2017
--- | --- | ---
General Partners' Capital Account, Units Outstanding (in units) | 1,722,336 |
Limited Partners' Capital Account, Units Outstanding (in units) | 152,736,142 |
Excess stock, par value | $ 0.01 | $ 0.01
Excess stock, shares authorized | 150,000,000 | 150,000,000
Excess stock, shares issued | 0 | 0
Excess stock, shares outstanding | 0 | 0
Preferred stock, par value | $ 0.01 | $ 0.01
Preferred stock, shares authorized | 50,000,000 | 50,000,000
Common stock, par value | $ 0.01 | $ 0.01
Common stock, shares authorized | 250,000,000 | 250,000,000
Common stock, shares issued | 154,537,378 | 154,404,186
Common stock, shares outstanding | 154,458,478 | 154,325,286
Treasury common stock at cost, shares | 78,900 | 78,900
Real estate, at cost (amounts related to variable interest entities (“VIEs”) of $7,481,015 and $7,172,718 at December 31, 2018 and 2017, respectively ) | $ 21,649,896 | $ 21,096,642
Less: accumulated depreciation (amounts related to VIEs of $(965,500) and $(854,172) at December 31, 2018 and 2017, respectively | (4,897,777) | (4,589,634)
Cash and cash equivalents (amounts related to VIEs of $296,806 and $304,955 at December 31, 2018 and 2017, respectively) | 543,359 | 434,767
Cash held in escrows | 95,832 | 70,602
Tenant and other receivables, net (amounts related to VIEs of $15,519 and $27,057 at December 31, 2018 and 2017, respectively) | 86,629 | 92,186
Accrued rental income, net (amounts related to VIEs of $272,466 and $242,589 at December 31, 2018 and 2017, respectively) | 934,896 | 861,575
Deferred charges, net (amounts related to VIEs of $263,402 and $281,678 at December 31, 2018 and 2017, respectively) | 678,724 | 679,038
Prepaid expenses and other assets (amounts related to VIEs of $26,513 and $33,666 at December 31, 2018 and 2017, respectively) | 80,943 | 77,971
Mortgage notes payable, net (amounts related to VIEs of $2,929,326 and $2,939,183 at December 31, 2018 and 2017, respectively) | 2,964,572 | 2,979,281
Accounts payable and accrued expenses (amounts related to VIEs of $75,786 and $106,683 at December 31, 2018 and 2017, respectively) | 276,645 | 331,500
Other liabilities (amounts related to VIEs of $200,344 and $164,806 at December 31, 2018 and 2017, respectively) | $ 503,726 | $ 443,980
Series B Cumulative Redeemable Preferred Stock / Unit [Member] |  |
Preferred stock, par value | $ 0.01 | $ 0.01
Preferred stock, shares authorized | 92,000 | 92,000
Series B Dividend Rate Percentage | 5.25% | 5.25%
Preferred stock / units, shares / units issued (in shares / units) | 80,000 | 80,000
Series B Liquidation Preference Per Share/ Unit | $ 2,500.00 | $ 2,500
Preferred stock / units, shares / units outstanding (in shares / units) | 80,000 | 80,000
Boston Properties Limited Partnership |  |
Redeemable Partnership Units Common Units Shares Outstanding (in units) | 16,783,558 | 16,810,378
Redeemable Partnership Units Common Units Long Term Incentive Units At Redemption Value Units Outstanding (in units) | 991,577 | 818,343
General Partners' Capital Account, Units Outstanding (in units) | 1,722,336 | 1,719,540
Limited Partners' Capital Account, Units Outstanding (in units) | 152,736,142 | 152,605,746
Real estate, at cost (amounts related to variable interest entities (“VIEs”) of $7,481,015 and $7,172,718 at December 31, 2018 and 2017, respectively ) | $ 21,251,540 | $ 20,685,164
Less: accumulated depreciation (amounts related to VIEs of $(965,500) and $(854,172) at December 31, 2018 and 2017, respectively | (4,800,475) | (4,496,959)
Cash and cash equivalents (amounts related to VIEs of $296,806 and $304,955 at December 31, 2018 and 2017, respectively) | 543,359 | 434,767
Cash held in escrows | 95,832 | 70,602
Tenant and other receivables, net (amounts related to VIEs of $15,519 and $27,057 at December 31, 2018 and 2017, respectively) | 86,629 | 92,186
Accrued rental income, net (amounts related to VIEs of $272,466 and $242,589 at December 31, 2018 and 2017, respectively) | 934,896 | 861,575
Deferred charges, net (amounts related to VIEs of $263,402 and $281,678 at December 31, 2018 and 2017, respectively) | 678,724 | 679,038
Prepaid expenses and other assets (amounts related to VIEs of $26,513 and $33,666 at December 31, 2018 and 2017, respectively) | 80,943 | 77,971
Mortgage notes payable, net (amounts related to VIEs of $2,929,326 and $2,939,183 at December 31, 2018 and 2017, respectively) | 2,964,572 | 2,979,281
Accounts payable and accrued expenses (amounts related to VIEs of $75,786 and $106,683 at December 31, 2018 and 2017, respectively) | 276,645 | 331,500
Other liabilities (amounts related to VIEs of $200,344 and $164,806 at December 31, 2018 and 2017, respectively) | $ 503,726 | $ 443,980
Boston Properties Limited Partnership | Series B Cumulative Redeemable Preferred Stock / Unit [Member] |  |
Series B Dividend Rate Percentage | 5.25% | 5.25%
Preferred stock / units, shares / units issued (in shares / units) | 80,000 | 80,000
Series B Liquidation Preference Per Share/ Unit | $ 2,500 | $ 2,500
Preferred stock / units, shares / units outstanding (in shares / units) | 80,000 | 80,000
Variable Interest Entity, Primary Beneficiary [Member] |  |
Real estate, at cost (amounts related to variable interest entities (“VIEs”) of $7,481,015 and $7,172,718 at December 31, 2018 and 2017, respectively ) | $ 7,481,015 | $ 7,172,718
Less: accumulated depreciation (amounts related to VIEs of $(965,500) and $(854,172) at December 31, 2018 and 2017, respectively | (965,500) | (854,172)
Cash and cash equivalents (amounts related to VIEs of $296,806 and $304,955 at December 31, 2018 and 2017, respectively) | 296,806 | 304,955
Tenant and other receivables, net (amounts related to VIEs of $15,519 and $27,057 at December 31, 2018 and 2017, respectively) | 15,519 | 27,057
Accrued rental income, net (amounts related to VIEs of $272,466 and $242,589 at December 31, 2018 and 2017, respectively) | 272,466 | 242,589
Deferred charges, net (amounts related to VIEs of $263,402 and $281,678 at December 31, 2018 and 2017, respectively) | 263,402 | 281,678
Prepaid expenses and other assets (amounts related to VIEs of $26,513 and $33,666 at December 31, 2018 and 2017, respectively) | 26,513 | 33,666
Mortgage notes payable, net (amounts related to VIEs of $2,929,326 and $2,939,183 at December 31, 2018 and 2017, respectively) | 2,929,326 | 2,939,183
Accounts payable and accrued expenses (amounts related to VIEs of $75,786 and $106,683 at December 31, 2018 and 2017, respectively) | 75,786 | 106,683
Other liabilities (amounts related to VIEs of $200,344 and $164,806 at December 31, 2018 and 2017, respectively) | 200,344 | 164,806
Variable Interest Entity, Primary Beneficiary [Member] | Boston Properties Limited Partnership |  |
Real estate, at cost (amounts related to variable interest entities (“VIEs”) of $7,481,015 and $7,172,718 at December 31, 2018 and 2017, respectively ) | 7,481,015 | 7,172,718
Less: accumulated depreciation (amounts related to VIEs of $(965,500) and $(854,172) at December 31, 2018 and 2017, respectively | (965,500) | (854,172)
Cash and cash equivalents (amounts related to VIEs of $296,806 and $304,955 at December 31, 2018 and 2017, respectively) | 296,806 | 304,955
Tenant and other receivables, net (amounts related to VIEs of $15,519 and $27,057 at December 31, 2018 and 2017, respectively) | 15,519 | 27,057
Accrued rental income, net (amounts related to VIEs of $272,466 and $242,589 at December 31, 2018 and 2017, respectively) | 272,466 | 242,589
Deferred charges, net (amounts related to VIEs of $263,402 and $281,678 at December 31, 2018 and 2017, respectively) | 263,402 | 281,678
Prepaid expenses and other assets (amounts related to VIEs of $26,513 and $33,666 at December 31, 2018 and 2017, respectively) | 26,513 | 33,666
Mortgage notes payable, net (amounts related to VIEs of $2,929,326 and $2,939,183 at December 31, 2018 and 2017, respectively) | 2,929,326 | 2,939,183
Accounts payable and accrued expenses (amounts related to VIEs of $75,786 and $106,683 at December 31, 2018 and 2017, respectively) | 75,786 | 106,683
Other liabilities (amounts related to VIEs of $200,344 and $164,806 at December 31, 2018 and 2017, respectively) | $ 200,344 | $ 164,806

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