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Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019
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Real estate, at cost (amounts related to variable interest entities (“VIEs”) of $6,592,019 and $6,497,031 at December 31, 2020 and December 31, 2019, respectively) | $ 22,969,110 | $ 22,502,976
Right of use assets - finance leases (amounts related to VIEs of $21,000 and $21,000 at December 31, 2020 and December 31, 2019, respectively) | 237,393 | 237,394
Less: accumulated depreciation (amounts related to VIEs of $(1,158,548) and $(1,058,495) at December 31, 2020 and December 31, 2019, respectively) | (5,534,102) | (5,266,798)
Cash and cash equivalents (amounts related to VIEs of $340,642 and $280,033 at December 31, 2020 and December 31, 2019, respectively) | 1,668,742 | 644,950
Tenant and other receivables, net (amounts related to VIEs of $10,911 and $28,918 at December 31, 2020 and December 31, 2019, respectively) | 77,411 | 112,807
Accrued rental income, net (amounts related to VIEs of $336,594 and $298,318 at December 31, 2020 and December 31, 2019, respectively) | 1,122,502 | 1,038,788
Deferred charges, net (amounts related to VIEs of $183,306 and $214,769 at December 31, 2020 and December 31, 2019, respectively) | 640,085 | 689,213
Prepaid expenses and other assets (amounts related to VIEs of $13,137 and $20,931 at December 31, 2020 and December 31, 2019, respectively) | 33,840 | 41,685
Mortgage notes payable, net (amounts related to VIEs of $2,907,590 and $2,918,806 at December 31, 2020 and December 31, 2019, respectively) | 2,909,081 | 2,922,408
Lease liabilities - finance leases (amounts related to VIEs of $20,306 and $20,189 at December 31, 2020 and December 31, 2019, respectively) | 236,492 | 224,042
Accounts payable and accrued expenses (amounts related to VIEs of $23,128 and $45,777 at December 31, 2020 and December 31, 2019, respectively) | 336,264 | 377,553
Other liabilities (amounts related to VIEs of $158,805 and $140,110 at December 31, 2020 and December 31, 2019, respectively) | $ 412,084 | $ 387,994
Reddemable deferred stock units, units | 72,966 | 60,676
Limited Partners' Capital Account, Units Outstanding (in units) | 153,987,904 |
General Partners' Capital Account, Units Outstanding (in units) | 1,730,921 |
Excess stock, par value | $ 0.01 | $ 0.01
Excess stock, shares authorized | 150,000,000 | 150,000,000
Excess stock, shares outstanding | 0 | 0
Excess stock, shares issued | 0 | 0
Preferred stock, par value | $ 0.01 | $ 0.01
Preferred stock, shares authorized | 50,000,000 | 50,000,000
Common Stock, Par or Stated Value Per Share | $ 0.01 | $ 0.01
Common stock, shares authorized | 250,000,000 | 250,000,000
Common stock, shares issued | 155,797,725 | 154,869,198
Common Stock, Shares, Outstanding | 155,718,825 | 154,790,298
Treasury common stock at cost, shares | 78,900 | 78,900
Boston Properties Limited Partnership |  |
Real estate, at cost (amounts related to variable interest entities (“VIEs”) of $6,592,019 and $6,497,031 at December 31, 2020 and December 31, 2019, respectively) | $ 22,592,301 | $ 22,107,755
Right of use assets - finance leases (amounts related to VIEs of $21,000 and $21,000 at December 31, 2020 and December 31, 2019, respectively) | 237,393 | 237,394
Less: accumulated depreciation (amounts related to VIEs of $(1,158,548) and $(1,058,495) at December 31, 2020 and December 31, 2019, respectively) | (5,428,576) | (5,162,908)
Cash and cash equivalents (amounts related to VIEs of $340,642 and $280,033 at December 31, 2020 and December 31, 2019, respectively) | 1,668,742 | 644,950
Tenant and other receivables, net (amounts related to VIEs of $10,911 and $28,918 at December 31, 2020 and December 31, 2019, respectively) | 77,411 | 112,807
Accrued rental income, net (amounts related to VIEs of $336,594 and $298,318 at December 31, 2020 and December 31, 2019, respectively) | 1,122,502 | 1,038,788
Deferred charges, net (amounts related to VIEs of $183,306 and $214,769 at December 31, 2020 and December 31, 2019, respectively) | 640,085 | 689,213
Prepaid expenses and other assets (amounts related to VIEs of $13,137 and $20,931 at December 31, 2020 and December 31, 2019, respectively) | 33,840 | 41,685
Mortgage notes payable, net (amounts related to VIEs of $2,907,590 and $2,918,806 at December 31, 2020 and December 31, 2019, respectively) | 2,909,081 | 2,922,408
Lease liabilities - finance leases (amounts related to VIEs of $20,306 and $20,189 at December 31, 2020 and December 31, 2019, respectively) | 236,492 | 224,042
Accounts payable and accrued expenses (amounts related to VIEs of $23,128 and $45,777 at December 31, 2020 and December 31, 2019, respectively) | 336,264 | 377,553
Other liabilities (amounts related to VIEs of $158,805 and $140,110 at December 31, 2020 and December 31, 2019, respectively) | $ 412,084 | $ 387,994
Reddemable deferred stock units, units | 72,966 | 60,676
NonControlling Interest Redeemable Partnership Units Common Units Shares Outstanding | 16,037,121 | 16,764,466
NonControlling Interest Redeemable Partnership Units Common Units Long Term Incentive Units At Redemption Value Shares Outstanding | 1,336,115 | 1,143,215
Limited Partners' Capital Account, Units Outstanding (in units) | 153,987,904 | 153,063,318
General Partners' Capital Account, Units Outstanding (in units) | 1,730,921 | 1,726,980
Series B Cumulative Redeemable Preferred Stock / Unit [Member] |  |
Preferred stock, par value | $ 0.01 | $ 0.01
Preferred stock, shares authorized | 92,000 | 92,000
Preferred stock / units, shares / units issued (in shares / units) | 80,000 | 80,000
Preferred stock / units, shares / units outstanding (in shares / units) | 80,000 | 80,000
Series B Dividend Rate Percentage | 5.25% | 5.25%
Series B Liquidation Preference Per Share/ Unit | $ 2,500.00 | $ 2,500
Series B Cumulative Redeemable Preferred Stock / Unit [Member] | Boston Properties Limited Partnership |  |
Preferred stock / units, shares / units issued (in shares / units) | 80,000 | 80,000
Preferred stock / units, shares / units outstanding (in shares / units) | 80,000 | 80,000
Series B Dividend Rate Percentage | 5.25% | 5.25%
Series B Liquidation Preference Per Share/ Unit | $ 2,500 | $ 2,500
Variable Interest Entity, Primary Beneficiary [Member] |  |
Real estate, at cost (amounts related to variable interest entities (“VIEs”) of $6,592,019 and $6,497,031 at December 31, 2020 and December 31, 2019, respectively) | $ 6,592,019 | $ 6,497,031
Right of use assets - finance leases (amounts related to VIEs of $21,000 and $21,000 at December 31, 2020 and December 31, 2019, respectively) | 21,000 | 21,000
Less: accumulated depreciation (amounts related to VIEs of $(1,158,548) and $(1,058,495) at December 31, 2020 and December 31, 2019, respectively) | (1,158,548) | (1,058,495)
Cash and cash equivalents (amounts related to VIEs of $340,642 and $280,033 at December 31, 2020 and December 31, 2019, respectively) | 340,642 | 280,033
Tenant and other receivables, net (amounts related to VIEs of $10,911 and $28,918 at December 31, 2020 and December 31, 2019, respectively) | 10,911 | 28,918
Accrued rental income, net (amounts related to VIEs of $336,594 and $298,318 at December 31, 2020 and December 31, 2019, respectively) | 336,594 | 298,318
Deferred charges, net (amounts related to VIEs of $183,306 and $214,769 at December 31, 2020 and December 31, 2019, respectively) | 183,306 | 214,769
Prepaid expenses and other assets (amounts related to VIEs of $13,137 and $20,931 at December 31, 2020 and December 31, 2019, respectively) | 13,137 | 20,931
Mortgage notes payable, net (amounts related to VIEs of $2,907,590 and $2,918,806 at December 31, 2020 and December 31, 2019, respectively) | 2,907,590 | 2,918,806
Lease liabilities - finance leases (amounts related to VIEs of $20,306 and $20,189 at December 31, 2020 and December 31, 2019, respectively) | 20,306 | 20,189
Accounts payable and accrued expenses (amounts related to VIEs of $23,128 and $45,777 at December 31, 2020 and December 31, 2019, respectively) | 23,128 | 45,777
Other liabilities (amounts related to VIEs of $158,805 and $140,110 at December 31, 2020 and December 31, 2019, respectively) | 158,805 | 140,110
Variable Interest Entity, Primary Beneficiary [Member] | Boston Properties Limited Partnership |  |
Real estate, at cost (amounts related to variable interest entities (“VIEs”) of $6,592,019 and $6,497,031 at December 31, 2020 and December 31, 2019, respectively) | 6,592,019 | 6,497,031
Right of use assets - finance leases (amounts related to VIEs of $21,000 and $21,000 at December 31, 2020 and December 31, 2019, respectively) | 21,000 | 21,000
Less: accumulated depreciation (amounts related to VIEs of $(1,158,548) and $(1,058,495) at December 31, 2020 and December 31, 2019, respectively) | (1,158,548) | (1,058,495)
Cash and cash equivalents (amounts related to VIEs of $340,642 and $280,033 at December 31, 2020 and December 31, 2019, respectively) | 340,642 | 280,033
Tenant and other receivables, net (amounts related to VIEs of $10,911 and $28,918 at December 31, 2020 and December 31, 2019, respectively) | 10,911 | 28,918
Accrued rental income, net (amounts related to VIEs of $336,594 and $298,318 at December 31, 2020 and December 31, 2019, respectively) | 336,594 | 298,318
Deferred charges, net (amounts related to VIEs of $183,306 and $214,769 at December 31, 2020 and December 31, 2019, respectively) | 183,306 | 214,769
Prepaid expenses and other assets (amounts related to VIEs of $13,137 and $20,931 at December 31, 2020 and December 31, 2019, respectively) | 13,137 | 20,931
Mortgage notes payable, net (amounts related to VIEs of $2,907,590 and $2,918,806 at December 31, 2020 and December 31, 2019, respectively) | 2,907,590 | 2,918,806
Lease liabilities - finance leases (amounts related to VIEs of $20,306 and $20,189 at December 31, 2020 and December 31, 2019, respectively) | 20,306 | 20,189
Accounts payable and accrued expenses (amounts related to VIEs of $23,128 and $45,777 at December 31, 2020 and December 31, 2019, respectively) | 23,128 | 45,777
Other liabilities (amounts related to VIEs of $158,805 and $140,110 at December 31, 2020 and December 31, 2019, respectively) | $ 158,805 | $ 140,110

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- Definition Total number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) issued to shareholders (includes related preferred shares that were issued, repurchased, and remain in the treasury). May be all or portion of the number of preferred shares authorized. Excludes preferred shares that are classified as debt. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -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=120391452&loc=d3e13212-122682 + Details
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