Tiaa Real Estate Account S-1 12 Mar 20 2019 FY IPO registration Financial data

Document And Entity Information

Document And Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2019	Jun. 30, 2019
Document and Entity Information [Abstract]
Entity Registrant Name	TIAA REAL ESTATE ACCOUNT
Document Type	S-1
Current Fiscal Year End Date
Entity Common Stock, Shares Outstanding (in shares)
Entity Public Float
Amendment Flag	false
Entity Central Index Key	0000946155
Entity Current Reporting Status
Entity Voluntary Filers
Entity Filer Category	Non-accelerated Filer
Entity Well-known Seasoned Issuer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company
Document Period End Date
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	FY

AUDITED CONSOLIDATED STATEMENTS

AUDITED CONSOLIDATED STATEMENTS OF ASSETS AND LIABILITIES - USD ($) shares in Millions, $ in Millions		Dec. 31, 2019	Dec. 31, 2018
Investments, at fair value:
Real estate properties (cost: $13,048.5 and $12,687.8)		$ 15,835	$ 15,531.1
Real estate joint ventures and funds (cost: $6,244.4 and $5,207.8)		7,516	6,532.5
Marketable securities:
Real estate related (cost: $686.0 and $1,274.7)	[1]	825.7	1,415.1
Other (cost: $4,144.7 and $4,088.9)		4,150.2	4,088.7
Loans receivable (cost: $1,504.5 and $910.6)		1,503.1	913
Loans receivable with related parties (cost: $69.3 and $0.0)		69	0
Total investments (cost: $25,697.4 and $24,169.8)		29,899	28,480.4
Cash and cash equivalents		15.1	3.8
Due from investment manager		5.5	2.2
Other	[2]	290.3	331.8
TOTAL ASSETS		30,209.9	28,818.2
LIABILITIES
Loans payable, at fair value (principal outstanding: $2,338.0 and $2,688.1)		2,365	2,608
Line of credit, at fair value		250	0
Accrued real estate property expenses		225.9	222.4
Payable for collateral for securities loaned		25.7	68.8
Other		35.4	76.4
TOTAL LIABILITIES		2,902	2,975.6
COMMITMENTS AND CONTINGENCIES
NET ASSETS
Accumulation Fund		26,759.1	25,320.1
Annuity Fund		548.8	522.5
TOTAL NET ASSETS		$ 27,307.9	$ 25,842.6
NUMBER OF ACCUMULATION UNITS OUTSTANDING (in shares)		60.8	60.7
NET ASSET VALUE, PER ACCUMULATION UNIT (in dollars per share)		$ 440.422	$ 417.416
[1]	Includes securities loaned of $25.2 million at December 31, 2019 and $67.4 million at December 31, 2018.
[2]	Includes cash collateral for securities loaned of $25.7 million at December 31, 2019 and $68.8 million at December 31, 2018.

AUDITED CONSOLIDATED STATEMEN_2

AUDITED CONSOLIDATED STATEMENTS OF ASSETS AND LIABILITIES (Parenthetical) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Statement of Financial Position [Abstract]
Securities loaned	$ 25.2	$ 67.4
Collateral for securities loaned	25.7	68.8
Real estate properties at cost	13,048.5	12,687.8
Real estate joint ventures and funds at cost	6,244.4	5,207.8
Real estate related marketable securities at cost	686	1,274.7
Other marketable securities at cost	4,144.7	4,088.9
Loans receivable at cost	1,504.5	910.6
Loans receivable from related parties at cost	69.3	0
Cost of total investments	25,697.4	24,169.8
Principal outstanding on loans payable	$ 2,338	$ 2,688.1

AUDITED CONSOLIDATED STATEMEN_3

AUDITED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Real estate income, net
Rental income	$ 1,103.5	$ 1,083.2	$ 1,059.6
Real estate property level expenses and taxes:
Operating expenses	237.5	228.6	221.2
Real estate taxes	187.4	178.9	166.7
Interest expense	105.7	113.9	89.7
Total real estate property level expenses and taxes	530.6	521.4	477.6
Real estate income, net	572.9	561.8	582
Income from real estate joint ventures and funds	214	204.7	214.1
Interest	173	120.4	54.1
Dividends	23.2	50.8	26.3
TOTAL INVESTMENT INCOME	983.1	937.7	876.5
Expenses
Investment management charges	68.1	62.1	72
Administrative charges	50	50.9	59.3
Distribution charges	31.7	28	25.7
Mortality and expense risk charges	1.3	1.3	1.2
Liquidity guarantee charges	57.8	50.5	47
TOTAL EXPENSES	208.9	192.8	205.2
INVESTMENT INCOME, NET	774.2	744.9	671.3
Net realized gain (loss) on investments
Real estate properties	583.1	242.7	42
Real estate joint ventures and funds	(114.4)	75.9	(21.9)
Marketable securities	301.1	12.8	17.6
Loans payable	0	(0.4)	0
Net realized gain on investments	769.8	331	37.7
Net change in unrealized appreciation (depreciation) on
Real estate properties	(56.8)	73.1	135.5
Real estate joint ventures and funds	50.3	55.5	146.8
Marketable securities	0.7	(103)	50
Loans receivable	(3.8)	0.3	1.2
Loans receivable with related parties	(0.3)	0	0
Loans payable	(107.1)	79.8	15.9
Net change in unrealized (depreciation) appreciation on investments and loans payable	(117)	105.7	349.4
NET REALIZED AND UNREALIZED GAIN ON INVESTMENTS AND LOANS PAYABLE	652.8	436.7	387.1
NET INCREASE IN NET ASSETS RESULTING FROM OPERATIONS	$ 1,427	$ 1,181.6	$ 1,058.4

AUDITED CONSOLIDATED STATEMEN_4

AUDITED CONSOLIDATED STATEMENTS OF CHANGES IN NET ASSETS - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
FROM OPERATIONS
Investment income, net	$ 774.2	$ 744.9	$ 671.3
Net realized gain on investments	769.8	331	37.7
Net change in unrealized (depreciation) appreciation on investments and loans payable	(117)	105.7	349.4
NET INCREASE IN NET ASSETS RESULTING FROM OPERATIONS	1,427	1,181.6	1,058.4
FROM PARTICIPANT TRANSACTIONS
Premiums	2,655.9	2,637.4	2,561.7
Annuity payments	(47.3)	(45)	(43.4)
Withdrawals and death benefits	(2,570.3)	(2,874)	(2,938.8)
NET INCREASE (DECREASE) IN NET ASSETS RESULTING FROM PARTICIPANT TRANSACTIONS	38.3	(281.6)	(420.5)
NET INCREASE IN NET ASSETS	1,465.3	900	637.9
NET ASSETS
Beginning of period	25,842.6	24,942.6	24,304.7
End of period	$ 27,307.9	$ 25,842.6	$ 24,942.6

AUDITED CONSOLIDATED STATEMEN_5

AUDITED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
CASH FLOWS FROM OPERATING ACTIVITIES
Net increase in net assets resulting from operations		$ 1,427	$ 1,181.6	$ 1,058.4
Adjustments to reconcile net changes in net assets resulting from operations to net cash provided by (used in) operating activities:
Net realized gain on investments		(769.8)	(331)	(37.7)
Net change in unrealized depreciation (appreciation) on investments and loans payable		117	(105.7)	(349.4)
Purchase of real estate properties		(1,059.7)	(786.3)	(538.2)
Capital improvements on real estate properties		(304.4)	(228.6)	(130.1)
Proceeds from sale of real estate properties		1,285.4	1,462.7	525.5
Purchases of long term investments		(1,373.4)	(1,422.2)	(592)
Proceeds from long term investments		1,210.5	756.4	385.3
Purchases and originations of loans receivable		(695.5)	(939.2)	(1.9)
Purchases and originations of loans receivable with related parties		(69.3)	0	0
Proceeds from sales of loans receivable		50.8	257.3	0
Proceeds from payoffs of loans receivable		50.8	68	0
(Increase) Decrease in other investments		(54.9)	(200.8)	165.9
Change in due from investment manager		(3.3)	(1.2)	4.9
Decrease (Increase) in other assets		23.3	(59.7)	58.2
(Decrease) Increase in other liabilities		(70.4)	63	(72.6)
NET CASH (USED IN) PROVIDED BY OPERATING ACTIVITIES		(235.9)	(285.7)	476.3
CASH FLOWS FROM FINANCING ACTIVITIES
Line of credit proceeds received		250	0	0
Mortgage loan proceeds received		47.5	712.8	0
Payments of mortgage loans		(106.8)	(152.2)	(50.6)
Premiums		2,655.9	2,637.4	2,561.7
Annuity payments		(47.3)	(45)	(43.4)
Withdrawals and death benefits		(2,570.3)	(2,874)	(2,938.8)
NET CASH PROVIDED BY (USED IN) FINANCING ACTIVITIES		229	279	(471.1)
NET (DECREASE) INCREASE IN CASH, CASH EQUIVALENTS AND RESTRICTED CASH		(6.9)	(6.7)	5.2
CASH, CASH EQUIVALENTS AND RESTRICTED CASH
Beginning of period cash, cash equivalents and restricted cash		47.3	54	48.8
Net (decrease) increase in cash, cash equivalents and restricted cash		(6.9)	(6.7)	5.2
TOTAL CASH, CASH EQUIVALENTS AND RESTRICTED CASH		40.4	47.3	54
SUPPLEMENTAL DISCLOSURES
Cash paid for interest		107.8	108.7	89.9
Debt assumed as part of a real estate acquisition		181	105.1	17.7
Loan assignment as part of a real estate disposition		471.8	216.5	45
Stock consideration received from the merger of marketable securities		0	6.1	0
Cash and cash equivalents		15.1	3.8	11.7
Restricted cash	[1]	25.3	43.5	42.3
TOTAL CASH, CASH EQUIVALENTS AND RESTRICTED CASH		$ 40.4	$ 47.3	$ 54
[1]	Restricted cash is included within other assets on the Account's Consolidated Statements of Assets and Liabilities.

Organization and Significant Ac

Organization and Significant Accounting Policies	12 Months Ended
	Dec. 31, 2019
Accounting Policies [Abstract]
Organization and Significant Accounting Policies	Organization and Significant Accounting Policies Business: The TIAA Real Estate Account (“Account”) is an insurance separate account of Teachers Insurance and Annuity Association of America (“TIAA”) and was established by resolution of TIAA’s Board of Trustees (the “Board”) on February 22, 1995, under the insurance laws of the State of New York, for the purpose of funding variable annuity contracts issued by TIAA. The Account offers individual and group accumulating annuity contracts (with contributions made on a pre-tax or after-tax basis), as well as individual lifetime and term-certain variable payout annuity contracts (including the payment of death benefits to beneficiaries). Investors are entitled to transfer funds to or from the Account, and make withdrawals from the Account on a daily basis, under certain circumstances. Funds invested in the Account for each category of contract are expressed in terms of units, and unit values will fluctuate depending on the Account’s performance. The investment objective of the Account is to seek favorable long-term returns primarily through rental income and appreciation of a diversified portfolio of directly held, private real estate investments and real estate-related investments while offering investors guaranteed, daily liquidity. The Account holds real estate properties directly and through subsidiaries wholly-owned by TIAA for the sole benefit of the Account. The Account also holds limited interests in real estate joint ventures and funds, as well as investments in loans receivable with commercial real estate properties as underlying collateral. Additionally, the Account invests in real estate-related and non-real estate-related publicly traded securities, cash and other instruments to maintain adequate liquidity levels for operating expenses, capital expenditures and to fund benefit payments (withdrawals, transfers and related transactions). The Consolidated Financial Statements were prepared in accordance with accounting principles generally accepted in the United States of America, which requires the use of estimates made by management. Actual results may vary from those estimates and such differences may be material. The following is a summary of the significant accounting policies of the Account. Basis of Presentation: The accompanying Consolidated Financial Statements include the Account and those subsidiaries wholly-owned by TIAA for the benefit of the Account. All significant intercompany accounts and transactions between the Account and such subsidiaries have been eliminated. The Accumulation Unit Value (“AUV”) used for financial reporting purposes may differ from the AUV used for processing transactions. The AUV used for financial reporting purposes includes security and participant transactions effective through the period end date to which this report relates. Total return is computed based on the AUV used for processing transactions. Determination of Investments at Fair Value: The Account reports all investments at fair value in accordance with the Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC”) 946, Financial Services—Investment Companies. Further in accordance with the adoption of the fair value option allowed under ASC 825, Financial Instruments , and at the election of Account management, loans payable and a line of credit are reported at fair value. The FASB has defined fair value as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants excluding transaction costs. The following is a description of the valuation methodologies used to determine the fair value of the Account’s investments and investment related loans payable. Valuation of Real Estate Properties —Investments in real estate properties are stated at fair value, as determined in accordance with policies and procedures reviewed by the Investment Committee of the Board and in accordance with the responsibilities of the Board as a whole. Accordingly, the Account does not record depreciation. Determination of fair value involves significant levels of judgment because the actual fair value of real estate can be determined only by negotiation between the parties in a sales transaction. The Account’s primary objective when valuing its real estate investments will be to produce a valuation that represents a reasonable estimate of the fair value of its investments. Implicit in the Account’s definition of fair value are the consummation of a sale as of a specified date and the passing of title from seller to buyer under conditions whereby: • Buyer and seller are typically motivated; • Both parties are well informed or well advised, and acting in what they consider their best interests; • A reasonable time is allowed for exposure in the open market; • Payment is made in terms of cash or in terms of financial arrangements comparable thereto; and • The price represents the normal consideration for the property sold unaffected by special or creative financing or sales concessions granted by anyone associated with the sale. Property and investment values are affected by, among other things, the availability of capital, occupancy rates, rental rates, and interest and inflation rates. As a result, determining real estate and investment values involves many assumptions. Key inputs and assumptions include rental income and expense amounts, related rental income and expense growth rates, capital expenditures, discount rates and capitalization rates. Valuation techniques include discounted cash flow analysis, prevailing market capitalization rates or multiples applied to earnings from the property, analysis of recent comparable sales transactions, actual sale negotiations and bona fide purchase offers received from third parties. Amounts ultimately realized from each investment may vary significantly from the fair value presented. Real estate properties owned by the Account are initially valued based on an independent third party appraisal, as reviewed by TIAA’s internal appraisal staff and as applicable by the Account’s independent fiduciary at the time of the closing of the purchase. Such initial valuation may result in a potential unrealized gain or loss reflecting the difference between an investment’s fair value (i.e., exit price) and its cost basis (which is inclusive of transaction costs). Subsequently, each property is appraised each quarter by an independent third party appraiser, reviewed by TIAA’s internal appraisal staff and as applicable the Account’s independent fiduciary. In general, the Account obtains appraisals of its real estate properties spread out throughout the quarter, which is intended to result in appraisal adjustments, and thus, adjustments to the valuations of its holdings (to the extent such adjustments are made) that happen regularly throughout each quarter and not on one specific day or month in each period. Further, management reserves the right to order an appraisal and/or conduct another valuation outside of the normal quarterly process when facts or circumstances at a specific property change. For example, under certain circumstances a valuation adjustment could be made when the account receives a bona fide bid for the sale of a property held within the Account or one of the Account’s joint ventures. Adjustments may be made for events or circumstances indicating an impairment of a tenant’s ability to pay amounts due to the Account under a lease (including due to a bankruptcy filing of that tenant). Alternatively, adjustments may be made to reflect the execution or renewal of a significant lease. Also, adjustments may be made to reflect factors (such as sales values for comparable properties or local employment rate) bearing uniquely on a particular region in which the Account holds properties. TIAA’s internal appraisal staff oversees the entire appraisal process, in conjunction with the Account’s independent fiduciary (the independent fiduciary is more fully described in the following paragraph). Any differences in the conclusions of TIAA’s internal appraisal staff and the independent appraiser will be reviewed by the independent fiduciary, which will make a final determination on the matter (which may include ordering a subsequent independent appraisal). The independent fiduciary, RERC, LLC, has been appointed by a special subcommittee of the Investment Committee of the Board to, among other things, oversee the appraisal process. The independent fiduciary must approve all independent appraisers used by the Account. All appraisals are performed in accordance with Uniform Standards of Professional Appraisal Practices, the real estate appraisal industry standards created by The Appraisal Foundation. Real estate appraisals are estimates of property values based on a professional’s opinion. Appraisals of properties held outside of the U.S. are performed in accordance with industry standards commonly applied in the applicable jurisdiction. These independent appraisers are always expected to be MAI-designated members of the Appraisal Institute (or its European equivalent, Royal Institute of Chartered Surveyors) and state certified appraisers from national or regional firms with relevant property type experience and market knowledge. Under the Account’s current procedures, each independent appraisal firm will be rotated off of a particular property at least every three years, although such appraisal firm may perform appraisals of other Account properties subsequent to such rotation. Also, the independent fiduciary can require additional appraisals if factors or events have occurred that could materially change a property’s value (including those identified above) and such change is not reflected in the quarterly valuation review, or otherwise to ensure that the Account is valued appropriately. The independent fiduciary must also approve any valuation change of real estate-related assets where a property’s value changed by more than 6% from the most recent independent annual appraisal, or if the value of the Account would change by more than 4% within any calendar quarter or more than 2% since the prior calendar month. When a real estate property is subject to a mortgage, the property is valued independently of the mortgage and the property and mortgage fair values are reported separately (see Valuation of Loans Payable ). The independent fiduciary reviews and approves all mortgage valuation adjustments before such adjustments are recorded by the Account. The Account continues to use the revised value for each real estate property and loan payable to calculate the Account’s daily net asset value until the next valuation review or appraisal. Valuation of Real Estate Joint Ventures —Real estate joint ventures are stated at the fair value of the Account’s ownership interests of the underlying entities. The Account’s ownership interests are valued based on the fair value of the underlying real estate, any related loans payable, and other factors, such as ownership percentage, ownership rights, buy/sell agreements, distribution provisions and capital call obligations. The fair value of real estate and loans payable held by joint ventures is determined in the same manner described above in Valuation of Real Estate Properties. The independent fiduciary reviews and approves all valuation adjustments before such adjustments are recorded by the Account. Upon the disposition of all real estate investments by an investee entity, the Account will continue to state its equity in the remaining net assets of the investee entity during the wind down period, if any, which occurs prior to the dissolution of the investee entity. Valuation of Real Estate Funds —Real estate fund interests are stated at the fair value of the Account’s ownership in the fund. Management uses net asset value information provided by limited partners as a practical expedient to estimate fair value. The Account receives estimates from limited partners on a quarterly basis, and audited information is provided annually. Upon receipt of the information, management reviews and concludes on whether the net asset values provided are an appropriate representation of the fair value of the Account's interests in the real estate funds and makes valuation adjustments as necessary. Valuation of real estate funds proceeds under the direction of the Investment Committee of the Board and in accordance with the responsibilities of the Board as a whole. Valuation of Marketable Securities —Equity securities listed or traded on any national market or exchange are valued at the last sale price as of the close of the principal securities market or exchange on which such securities are traded or, if there is no sale, at the mean of the last bid and asked prices on such market or exchange, exclusive of transaction costs. Valuation of Debt Securities —Debt securities with readily available market quotations, other than money market instruments, are generally valued at the most recent bid price or the equivalent quoted yield for such securities (or those of comparable maturity, quality and type). Debt securities for which market quotations are not readily available, are valued at fair value as determined by management and the Investment Committee of the Board and in accordance with the responsibilities of the Board as a whole. Short-term investments are valued in the same manner as debt securities, as described above. Money market instruments are valued at amortized cost, which approximates fair value. Valuation of Loans Receivable (i.e. the Account as a creditor) —Loans receivable are stated at fair value and are initially valued at the face amount of the loan funding. Subsequently, loans receivable are valued at least quarterly by TIAA’s internal valuation department based on market factors, such as market interest rates and spreads for comparable loans, the liquidity for loans of similar characteristics, the performance of the underlying collateral (such as the loan-to-value ratio and the cash flow of the underlying collateral) and the credit quality of the counterparty. The independent fiduciary reviews and approves all loan receivable valuation adjustments before such adjustments are recorded by the Account. The Account continues to use the revised value for each loan receivable to calculate the Account’s daily net asset value until the next valuation review. Valuation of Loans Payable (i.e. the Account as a debtor) —Mortgage or other loans payable, including the Accounts line of credit, are stated at fair value. The estimated fair value of loans payable is generally based on the amount at which the liability could be transferred in a current transaction, exclusive of transaction costs. Fair values are estimated based on market factors, such as market interest rates and spreads on comparable loans, the liquidity for loans of similar characteristics, the performance of the underlying collateral (such as the loan-to-value ratio and the cash flow of the underlying collateral), the maturity date of the loan, the return demands of the market, and the credit quality of the Account. Different assumptions or changes in future market conditions could significantly affect estimated fair values. At times, the Account may assume debt in connection with the purchase of real estate (including under the Account's line of credit or additional credit facilities). The independent fiduciary reviews and approves all valuation adjustments before such adjustments are recorded by the Account. See Note 5 — Assets and Liabilities Measured at Fair Value on a Recurring Basis for further discussion and disclosure regarding the determination of the fair value of the Account’s investments. Accumulation and Annuity Funds: The accumulation fund represents the net assets attributable to participants in the accumulation phase of their investment (“Accumulation Fund”). The annuity fund represents the net assets attributable to the participants currently receiving annuity payments (“Annuity Fund”). The net increase or decrease in net assets from investment operations is apportioned between the accounts based upon their relative daily net asset values. Once an Account participant begins receiving lifetime annuity income benefits, payment levels cannot be reduced as a result of the Account’s actual mortality experience. In addition, the contracts pursuant to which the Account is offered are required to stipulate the maximum expense charge for all Account level expenses that can be assessed, which is not to exceed 2.5% of average net assets per year. The Account pays a fee to TIAA to assume mortality and expense risks. Accounting for Investments: The investments held by the Account are accounted for as follows: Real Estate Properties —Rent from real estate properties consists of all amounts earned under tenant operating leases, including base rent, recoveries of real estate taxes and other expenses and charges for miscellaneous services provided to tenants. Rental income is recognized in accordance with the billing terms of the lease agreements. The Account bears the direct expenses of the real estate properties owned. These expenses include, but are not limited to, fees to local property management companies, property taxes, utilities, maintenance, repairs, insurance, and other operating and administrative costs. An estimate of the net operating income earned from each real estate property is accrued by the Account on a daily basis and such estimates are adjusted when actual operating results are determined. Real Estate Joint Ventures —The Account has ownership interests in various real estate joint ventures (collectively, the “joint ventures”). The Account records its contributions as increases to its investments in the joint ventures, and distributions from the joint ventures are treated as income within income from real estate joint ventures and limited partnerships in the Account’s Consolidated Statements of Operations. Distributions that are identified as returns of capital are recorded as a reduction to the cost basis of the investment, whereas distributions identified as capital gains or losses are recorded as realized gains or losses. Income distributions from the joint ventures are recorded based on the Account’s proportional interest of the income distributed by the joint ventures. Income and losses incurred but not yet distributed or realized from the Account by the joint ventures are recorded as unrealized gains and losses. Real Estate Funds —The Account has limited ownership interests in various private real estate funds. The Account records its contributions as increases to the investments, and distributions from the investments are treated as income within income from real estate joint ventures and funds in the Account’s Consolidated Statements of Operations. Distributions that are identified as returns of capital are recorded as a reduction to the cost basis of the investment, whereas distributions identified as capital gains or losses are recorded as realized gains or losses. Unrealized gains and losses are recorded based upon the changes in the net asset values of the real estate funds as determined from the financial statements of the real estate funds when received by the Account. Prior to the receipt of the financial statements from the real estate funds, the Account estimates the value of its interest using information provided by the limited partners. Changes in value based on such estimates are recorded by the Account as unrealized gains and losses. Marketable Securities —Transactions in marketable securities are accounted for as of the date the securities are purchased or sold (trade date). Interest income is recorded as earned. Dividend income is recorded on the ex-dividend date within dividend income. Dividends that are identified as returns of capital are recorded as a reduction to the cost basis of the investment, whereas dividends identified as capital gains or losses are recorded as realized gains or losses. Realized gains and losses on securities transactions are accounted for on the specific identification method. Loans Receivable —The Account may originate, purchase or sell loans collateralized by real estate. The cost basis of originated loans is comprised of the principal balance and direct costs incurred that represent a component of loan’s reported fair value. The cost basis of purchased loans consists of the purchase price of the loan and additional direct costs incurred that represent a component of the loan’s reported fair value. Additional costs incurred by the Account to originate or purchase loans that do not represent a component of a loan’s fair value are recorded as expenses in the period incurred. Nonrefundable origination fees paid by borrowers are recognized as interest income once all activities required to execute the loan are completed. Prepayment fees received from the payoff of loans in advance of their maturity date are recognized as interest income on the date the payoff occurs. Interest income from loans in accrual status is recognized based on the current coupon rate of the loans. Interest income from loans in accrual status is recognized based on the current coupon rate of the loans. Interest income accruals are suspended when a loan becomes a non-performing loan, defined as a loan more than ninety days in arrears or at any point when management believes the full collection of principal is doubtful. Interest income on non-performing loans is recognized only as cash payments are received. Loans can be rehabilitated to normal accrual status once all past due interest has been collected and management believes the full collection of principal is likely. Realized and Unrealized Gains and Losses —Realized gains and losses are recorded at the time an investment is sold or a distribution is received in relation to an investment sale from a joint venture or fund. Real estate and loan receivable transactions are accounted for as of the date on which the purchase or sale transactions close (settlement date). The Account recognizes a realized gain on the sale of an investment to the extent that the contract sales price exceeds the cost-to-date of the investment being sold. A realized loss occurs when the cost-to-date exceeds the sales price. Realized gains and losses from partial sales of non-financial assets are recognized in accordance with ASC 610-20 - Gains and Losses from the Derecognition of Nonfinancial Assets . Realized gains and losses from the sale of financial assets are recognized in accordance with ASC 860 - Transfers and Servicing . Unrealized gains and losses are recorded as the fair values of the Account’s investments are adjusted, and as discussed within the Real Estate Joint Ventures, Real Estate Funds and Loans Receivable sections above. Net Assets —The Account’s net assets as of the close of each valuation day are valued by taking the sum of: • the value of the Account’s cash; cash equivalents, and short-term and other debt instruments; • the value of the Account’s other securities and other non-real estate assets; • the value of the individual real properties (based on the most recent valuation of that property) and other real estate-related investments owned by the Account; • an estimate of the net operating income accrued by the Account from its properties, other real estate-related investments and non-real estate-related investments (including short-term marketable securities) since the end of the prior valuation day; and • actual net operating income earned from the Account’s properties, other real estate-related investments and non-real estate-related investments (but only to the extent any such item of income differs from the estimated income accrued for on such investments), and then reducing the sum by liabilities held within the Account, including the daily investment management fee, administration and distribution fees, mortality and expense fee, liquidity guarantee fee, and certain other expenses attributable to operating the Account. Daily estimates of net operating income are adjusted to reflect actual net operating income on a monthly basis, at which time such adjustments (if any) are reflected in the Account’s unit value. After the end of every quarter, the Account reconciles the amount of expenses deducted from the Account (which is established in order to approximate the costs that the Account will incur) with the expenses the Account actually incurred. If there is a difference, the Account adds it to or deducts it from the Account in equal daily installments over the remaining days of the following quarter. Material differences may be repaid in the current calendar quarter. The Account’s at-cost deductions are based on projections of Account assets and overall expenses, and the size of any adjusting payments will be directly affected by the difference between management’s projections and the Account’s actual assets or expenses. Variable Interest Entities: Variable interests are financial relationships which expose a reporting entity to the risks and rewards of variability in the entity's assets and operations. When variable interests exist, they are subject to evaluation under the variable interest entity ("VIE") model if any one of the following four characteristics are present: a) the entity is insufficiently capitalized; b) the equity holders do not have power to control the activities that most significantly impact the entity's financial performance; c) the voting rights of the equity holders are not proportionate to their economic interests; or d) the equity holders are not exposed to the residual losses or benefits that would normally be associated with equity interests. ASC 810 - Consolidation prohibits a reporting entity that qualifies as an investment company under ASC 946 - Financial Services - Investment Companies from consolidating an investee that is not an investment company. This scope exception does not apply to situations in which an investment company has an interest in another investment company. Accordingly, the Account's investments in other investment companies (e.g., real estate funds) are subject to evaluation under the VIE model. The Account consolidates a VIE if it concludes that the Account is the primary beneficiary of the VIE. The primary beneficiary has both: a) the power to direct the activities of a VIE that most significantly impact the VIE's economic performance; and b) the obligation to absorb losses or the right to receive benefits that could potentially be significant to the VIE. The following activities have been identified by the Account as having the most significant impact on a VIE's economic performance: • control over the ability to acquire and dispose of investments held by the entity; • the ability to kick out a managing entity without cause, either unilaterally or with a group of equity investors; • the ability to modify the power of the managing entity without its consent; and • control over the day-to-day decision making of the underlying investments An equity investor in a VIE may not actively be involved in the significant activities (i.e., it may cede day-to-day decision making to a third party), but if the equity investor has approval rights or some other mechanism to retain ultimate control, the equity investor with these rights would be concluded as having power over the activity. On a quarterly basis, the Account evaluates all involvements with VIEs, including any changes to governing powers of continuing VIEs. The consolidation status of VIEs may change as a result of such continued evaluation. At the reporting date, the Account was not deemed to be the primary beneficiary of any VIEs. Refer to Note 7—Investments in Real Estate Funds for additional detail. Cash and Cash Equivalents: Cash and cash equivalents are balances held by the Account in bank deposit accounts which, at times, exceed federally insured limits. The Account’s management monitors these balances to mitigate the exposure of risk due to concentration and has not experienced any losses from such concentration. Other Assets and Other Liabilities: Other assets and other liabilities consist of operating assets and liabilities utilized and held at each individual real estate property investment. Other assets consist of, amongst other items, cash, tenant receivables and prepaid expenses; whereas other liabilities primarily consist of security deposits. Other assets also include cash collateral held for securities on loan. Federal Income Taxes: Based on provisions of the Internal Revenue Code, Section 817, the Account is taxed as a segregated asset account of TIAA and as such, the Account incurs no material federal income tax attributable to the net investment activity of the Account. The Account’s federal income tax return is generally subject to examination for a period of three years after filed. State and local tax returns may be subject to examination for an additional period of time depending on the jurisdiction. Management has analyzed the Account’s tax positions taken for all open federal income tax years and has concluded that no provision for federal income tax is required in the Account’s Consolidated Financial Statements. Restricted Cash: The Account held restricted cash in escrow accounts for security deposits, as required by certain states, as well as property taxes, insurance, and various other property related matters as required by certain creditors related to outstanding loans payable collateralized by certain real estate investments. These amounts are recorded within other assets on the Consolidated Statements of Assets and Liabilities. See Note 9—Loans Payable for additional information regarding the Account’s outstanding loans payable. Changes in Net Assets: Premiums include premiums paid by existing accumulation unit holders in the Account and transfers into the Account. Withdrawals and death benefits include withdrawals out of the Account which include transfers out of the Account and required minimum distributions. Due to/from Investment Manager: Due to/from investment manager represents amounts that are to be paid or received by TIAA on behalf of the Account. Amounts generally are paid or received by the Account within one or two business days and no interest is contractually charged on these amounts. Securities Lending: The Account may lend securities to qualified borrowers to earn additional income. The Account receives cash collateral against the loaned securities and maintains cash collateral in an amount not less than 100% of the market value of loaned securities during the period of the loan; any additional collateral required due to changes in security values is delivered to the Account the next business day. Cash collateral received by the Account is invested exclusively in an interest-bearing deposit account. The value of the loaned securities and the liability to return the cash collateral received are reflected in the Consolidated Statements of Assets and Liabilities. When loaning securities, the Account retains the benefits of owning the securities, including the economic equivalent of dividends or interest generated by the securities. All income generated by the securities lending program is reflected within interest income on the Consolidated Statements of Operations. Securities lending transactions are for real-estate related equity securities, and the resulting loans are continuous, can be recalled at any time, and have no set maturity. Securities lending income recognized by the Account consists of interest earned on cash collateral and lending fees, net of any rebates to the borrower and compensation to the agent. Such income is reflected within interest income on the Consolidated Statements of Operations. In lending its securities, the Account bears the market risk with respect to the investment of collateral and the risk that the agent may default on its contractual obligations to the Account. The agent bears the risk that the borrower may default on its obligation to return the loaned securities as the agent is contractually obligated to indemnify the Account if at the time of a default by a borrower some or all of the loan securities have not been returned. Adopted Accounting Pronouncements: In February 2016, the FASB issued Accounting Standards Update 2016-02 Leases (Topic 842) (“ASU 2016-02”) which supersedes Topic 840, Leases. ASU 2016-02 applies to all entities that enter into leases. Lessees are required to report assets and lia

Related Party Transactions

Related Party Transactions	12 Months Ended
	Dec. 31, 2019
Related Party Transactions [Abstract]
Related Party Transactions	Related Party Transactions Investment management, administrative and distribution services are provided to the Account at cost by TIAA. Services provided at cost are paid by the Account on a daily basis based upon projected expenses to be provided to the Account. Payments are adjusted periodically to ensure daily payments are as close as possible to the Account’s actual expenses incurred. Differences between actual expenses and the amounts paid by the Account are reconciled and adjusted quarterly. Investment management services for the Account are provided by TIAA officers, under the direction and control of the Board, pursuant to investment management procedures adopted by TIAA for the Account. TIAA’s investment management decisions for the Account are subject to review by the Account’s independent fiduciary. TIAA also provides various portfolio accounting and related services for the Account. The Account is a party to the Distribution Agreement for the Contracts Funded by the TIAA Real Estate Account (the “Distribution Agreement”), dated January 1, 2008, by and among TIAA, for itself and on behalf of the Account, and TIAA-CREF Individual and Institutional Services, LLC (“Services”), a wholly-owned subsidiary of TIAA, a registered broker-dealer and a member of the Financial Industry Regulatory Authority. Pursuant to the Distribution Agreement, Services performs distribution services for the Account which include, among other things, (i) distribution of annuity contracts issued by TIAA and funded by the Account, (ii) advising existing annuity contract owners in connection with their accumulations and (iii) helping employers implement and manage retirement plans. In addition, TIAA performs administrative functions for the Account, which include, among other things, (i) maintaining accounting records and performing accounting services, (ii) receiving and allocating premiums, (iii) calculating and making annuity payments, (iv) processing withdrawal requests, (v) providing regulatory compliance and reporting services, (vi) maintaining the Account’s records of contract ownership and (vii) otherwise assisting generally in all aspects of the Account’s operations. Both distribution services (pursuant to the Distribution Agreement) and administrative services are provided to the Account by Services and TIAA, as applicable, on an at cost basis.The Distribution Agreement is terminable by either party upon 60 days written notice and terminates automatically upon any assignment thereof. In addition to providing the services described above, TIAA charges the Account fees to bear certain mortality and expense risks, and risks with providing the liquidity guarantee. These fees are charged as a percentage of the net assets of the Account. Rates for these fees are established annually. Once an Account participant begins receiving lifetime annuity income benefits, payment levels cannot be reduced as a result of the Account’s actual mortality experience. As such, mortality and expense risk expenses are contractual charges for TIAA’s assumption of this risk. The liquidity guarantee ensures that sufficient funds are available to meet participant transfer and cash withdrawal requests in the event that the Account’s cash flows and liquid investments are insufficient to fund such requests. Expenses for the services and fees described above are identified as such in the accompanying Consolidated Statements of Operations and are further identified as "Expenses" in Note 11—Financial Highlights. The independent fiduciary, which has the right to adjust the trigger point, has established the trigger point at 45% of the outstanding accumulation units and it will continue to monitor TIAA’s ownership interest in the Account and provide further recommendations as necessary. The Account has loans receivable outstanding with related parties as of December 31, 2019. The loans are with joint ventures in which the Account also has an equity interest. The loans are held at fair value in accordance with the valuation policies described in Note 1—Organization and Significant Accounting Policies. The following table presents the key terms of the loans as of the reporting date: Related Party Equity Ownership Interest Interest Rate Maturity Date Fair Value at Principal December 31, 2019 December 31, 2018 2019 2018 36.5 — MRA Hub 34 Holding, LLC 95.00% 2.50% + LIBOR 9/1/2022 $ 36.5 $ — 32.8 — THP Student Housing, LLC 97.00% 3.200% 9/1/2024 32.5 — TOTAL LOANS RECEIVABLE WITH RELATED PARTIES $ 69.0 $ —

Concentration Risk

Concentration Risk	12 Months Ended
	Dec. 31, 2019
Risks and Uncertainties [Abstract]
Concentration Risk	Concentration Risk Concentration risk may arise when a number of properties are located in a similar geographic region such that the economic conditions of that region could impact tenants’ obligations to meet their contractual obligations or cause the values of individual properties to decline. Additionally, concentrations of risk may arise if any one tenant comprises a significant amount of the Account's rent, or if tenants are concentrated in a particular industry. As of December 31, 2019 , the Account had no significant concentrations of tenants as no single tenant had annual contract rent that made up more than 3% of the rental income of the Account. Moreover, the Account's tenants have no notable concentration present in any one industry. There are no significant lease expirations scheduled to occur over the next twelve months. The Account’s wholly-owned real estate investments and investments in joint ventures are located in the United States. The following table represents the diversification of the Account’s portfolio by region and property type as of December 31, 2019 : Diversification by Fair Value (1) West East South Midwest Total Office 13.1 % 18.8 % 5.3 % — % 37.2 % Apartment 10.1 % 7.7 % 7.4 % 1.0 % 26.2 % Retail 6.9 % 3.9 % 7.7 % 0.8 % 19.3 % Industrial 9.0 % 1.6 % 4.7 % 0.5 % 15.8 % Other (2) 0.5 % 0.4 % 0.6 % — % 1.5 % Total 39.6 % 32.4 % 25.7 % 2.3 % 100.0 % (1) Wholly-owned properties are represented at fair value and gross of any debt, while joint venture properties are represented at the net equity value. (2) Represents interests in Storage Portfolio investments, a hotel investment and land. Properties in the “West” region are located in: AK, AZ, CA, CO, HI, ID, MT, NM, NV, OR, UT, WA, WY Properties in the “East” region are located in: CT, DC, DE, KY, MA, MD, ME, NC, NH, NJ, NY, PA, RI, SC, VA, VT, WV Properties in the “South” region are located in: AL, AR, FL, GA, LA, MS, OK, TN, TX Properties in the “Midwest” region are located in: IA, IL, IN, KS, MI, MN, MO, ND, NE, OH, SD, WI

Leases

Leases	12 Months Ended
	Dec. 31, 2019
Leases [Abstract]
Leases	Leases The Account’s wholly-owned real estate properties are leased to tenants under operating lease agreements which expire on various dates through 2049. Rental income is recognized in accordance with the billing terms of the lease agreements. The leases do not have material variable payments, material residual value guarantees or material restrictive covenants. Certain leases have the option to extend or terminate at the tenant's discretion, with termination options resulting in additional fees due to the Account. Aggregate minimum annual rentals for wholly-owned real estate investments owned by the Account through the non-cancelable lease term, excluding short-term residential leases, are as follows (millions): For the Years Ending December 31, 2020 $ 550.4 2021 505.0 2022 442.1 2023 381.2 2024 316.6 Thereafter 1,078.4 Total $ 3,273.7 Certain leases provide for additional rental amounts based upon the recovery of actual operating expenses in excess of specified base amounts, sales volume or contractual increases as defined in the lease agreement. These contractual contingent rentals are not included in the table above. The Account has ground leases for which the Account is the lessee. The leases do not contain material residual value guarantees or material restrictive covenants. The fair value of right-of-use assets and leases liabilities related to ground leases are reflected on the balance sheet within other assets and other liabilities, respectively. The fair values and key terms of the right-of-use assets and lease liabilities related to the Account's ground leases are as follows (millions): As of December 31, 2019 Assets: Right-of-use assets, at fair value $ 25.7 Liabilities: Ground lease liabilities, at fair value $ 25.7 Key Terms Weighted-average remaining lease term (years) 84.4 Weighted-average discount rate (1) 6.15 % (1) Discount rates are reflective of the rates utilized during the most recent appraisal of the associated real estate investments. For the year ended December 31, 2019 , operating lease costs related to ground leases were $1.3 million . These costs include variable lease costs, which are immaterial. Aggregate future minimum annual payments for ground leases held by the Account are as follows (millions): For the Years Ending December 31, 2020 $ 1.2 2021 1.2 2022 1.2 2023 1.2 2024 1.3 Thereafter 375.9 Total $ 382.0
Leases	Leases The Account’s wholly-owned real estate properties are leased to tenants under operating lease agreements which expire on various dates through 2049. Rental income is recognized in accordance with the billing terms of the lease agreements. The leases do not have material variable payments, material residual value guarantees or material restrictive covenants. Certain leases have the option to extend or terminate at the tenant's discretion, with termination options resulting in additional fees due to the Account. Aggregate minimum annual rentals for wholly-owned real estate investments owned by the Account through the non-cancelable lease term, excluding short-term residential leases, are as follows (millions): For the Years Ending December 31, 2020 $ 550.4 2021 505.0 2022 442.1 2023 381.2 2024 316.6 Thereafter 1,078.4 Total $ 3,273.7 Certain leases provide for additional rental amounts based upon the recovery of actual operating expenses in excess of specified base amounts, sales volume or contractual increases as defined in the lease agreement. These contractual contingent rentals are not included in the table above. The Account has ground leases for which the Account is the lessee. The leases do not contain material residual value guarantees or material restrictive covenants. The fair value of right-of-use assets and leases liabilities related to ground leases are reflected on the balance sheet within other assets and other liabilities, respectively. The fair values and key terms of the right-of-use assets and lease liabilities related to the Account's ground leases are as follows (millions): As of December 31, 2019 Assets: Right-of-use assets, at fair value $ 25.7 Liabilities: Ground lease liabilities, at fair value $ 25.7 Key Terms Weighted-average remaining lease term (years) 84.4 Weighted-average discount rate (1) 6.15 % (1) Discount rates are reflective of the rates utilized during the most recent appraisal of the associated real estate investments. For the year ended December 31, 2019 , operating lease costs related to ground leases were $1.3 million . These costs include variable lease costs, which are immaterial. Aggregate future minimum annual payments for ground leases held by the Account are as follows (millions): For the Years Ending December 31, 2020 $ 1.2 2021 1.2 2022 1.2 2023 1.2 2024 1.3 Thereafter 375.9 Total $ 382.0

Assets and Liabilities Measured

Assets and Liabilities Measured at Fair Value on a Recurring Basis	12 Months Ended
	Dec. 31, 2019
Fair Value Disclosures [Abstract]
Assets and Liabilities Measured at Fair Value on a Recurring Basis	Assets and Liabilities Measured at Fair Value on a Recurring Basis Valuation Hierarchy: The Account’s fair value measurements are grouped categorically into three levels, as defined by the FASB. The levels are defined as follows: • Level 1 fair value inputs are quoted prices for identical items in active, liquid and visible markets such as stock exchanges. • Level 2 fair value inputs are observable information for similar items in active or inactive markets, and appropriately consider counterparty creditworthiness in the valuations. • Level 3 fair value inputs reflect our best estimate of inputs and assumptions market participants would use in pricing an asset or liability at the measurement date. The inputs are unobservable in the market and significant to the valuation estimate. An investment’s categorization within the valuation hierarchy described above is based upon the lowest level of input that is significant to the fair value measurement. Real estate fund investments are excluded from the valuation hierarchy, as these investments are fair valued using their net asset value as a practical expedient since market quotations or values from independent pricing services are not readily available. See Note 1 - Organization and Significant Accounting Policies for further discussion regarding the use of a practical expedient for the valuation of real estate funds. The Account’s determination of fair value is based upon quoted market prices, where available. If listed prices or quotes are not available, fair value is based upon vendor-provided, evaluated prices or internally developed models that primarily use market-based or independently sourced market data, including interest rate yield curves, market spreads, and currency rates. Valuation adjustments will be made to reflect changes in credit quality, counterparty’s creditworthiness, the Account’s creditworthiness, liquidity, and other observable and unobservable inputs that are applied consistently over time. The methods described above are considered to produce fair values that represent an estimate by management of what an unaffiliated buyer in the marketplace would pay to purchase the asset or would receive to transfer the liability. Since fair value calculations involve significant professional judgment in the application of both observable and unobservable attributes, actual realizable values or future fair values may differ from amounts reported. Furthermore, while the Account believes its valuation methods are appropriate and consistent with other market participants, the use of different methodologies or assumptions to determine the fair value of certain financial instruments, while reasonable, could result in different estimates of fair value at the reporting date. As discussed in Note 1 — Organization and Significant Accounting Policies in more detail, the Account generally obtains independent third party appraisals on a quarterly basis; there may be circumstances in the interim in which the true realizable value of a property is not reflected in the Account’s daily net asset value calculation or in the Account’s periodic Consolidated Financial Statements. This disparity may be more apparent when the commercial and/or residential real estate markets experience an overall and possibly dramatic decline (or increase) in property values in a relatively short period of time between appraisals. The following tables show the major categories of assets and liabilities measured at fair value on a recurring basis as of December 31, 2019 and 2018 , using unadjusted quoted prices in active markets for identical assets (Level 1); significant other observable inputs (Level 2); significant unobservable inputs (Level 3); and Practical Expedient (millions): Description Level 1: Quoted Prices in Active Markets for Identical Assets Level 2: Significant Other Observable Inputs Level 3: Significant Unobservable Inputs Fair Value Using Practical Expedient Total at December 31, 2019 Real estate properties $ — $ — $ 15,835.0 $ — $ 15,835.0 Real estate joint ventures — — 7,204.2 — 7,204.2 Real estate funds — — — 311.8 311.8 Marketable securities: Real estate-related 825.7 — — — 825.7 Government agency notes — 259.6 — — 259.6 United States Treasury securities — 2,589.1 — — 2,589.1 Corporate bonds — 1,268.3 — — 1,268.3 Municipal bonds — 33.2 — — 33.2 Loans receivable (1) — — 1,572.1 — 1,572.1 Total Investments at $ 825.7 $ 4,150.2 $ 24,611.3 $ 311.8 $ 29,899.0 Loans payable $ — $ — $ (2,365.0 ) $ — $ (2,365.0 ) Line of credit $ — $ — $ (250.0 ) $ — $ (250.0 ) (1) Amount shown is reflective of loans receivable and loans receivable with related parties. Description Level 1: Quoted Prices in Active Markets for Identical Assets Level 2: Significant Other Observable Inputs Level 3: Significant Unobservable Inputs Fair Value Using Practical Expedient Total at December 31, 2018 Real estate properties $ — $ — $ 15,531.1 $ — $ 15,531.1 Real estate joint ventures — — 6,356.6 — 6,356.6 Real estate funds — — — 175.9 175.9 Marketable securities: Real estate-related 1,415.1 — — — 1,415.1 Government agency notes — 2,050.7 — — 2,050.7 United States Treasury securities — 2,038.0 — — 2,038.0 Loans receivable — — 913.0 — 913.0 Total Investments at $ 1,415.1 $ 4,088.7 $ 22,800.7 $ 175.9 $ 28,480.4 Loans payable $ — $ — $ (2,608.0 ) $ — $ (2,608.0 ) The following tables show the reconciliation of the beginning and ending balances for assets and liabilities measured at fair value on a recurring basis using significant unobservable inputs (Level 3) during the years ended December 31, 2019 and 2018 (millions): Real Estate Properties Real Estate Joint Ventures Loans Receivable (3) Total Level 3 Investments Line of Credit For the year ended December 31, 2019 Beginning balance January 1, 2019 $ 15,531.1 $ 6,356.6 $ 913.0 $ 22,800.7 $ (2,608.0 ) $ — Total realized and unrealized gains(losses) included in changes in net assets 526.3 (100.3 ) (4.1 ) 421.9 (107.1 ) — Purchases (1) 1,534.9 953.0 764.8 3,252.7 (228.5 ) (250.0 ) Sales (1,757.3 ) — — (1,757.3 ) — — Settlements (2) — (5.1 ) (101.6 ) (106.7 ) 578.6 — Ending balance December 31, 2019 $ 15,835.0 $ 7,204.2 $ 1,572.1 $ 24,611.3 $ (2,365.0 ) $ (250.0 ) Real Estate Properties Real Estate Joint Ventures Loans Receivable Total Level 3 Investments Loans Payable For the year ended December 31, 2018 Beginning balance January 1, 2018 $ 15,742.7 $ 5,860.6 $ 298.8 $ 21,902.1 $ (2,238.3 ) Total realized and unrealized gains included in changes in net assets 315.8 116.3 0.3 432.4 79.4 Purchases (1) 1,151.8 941.5 939.2 3,032.5 (817.9 ) Sales (1,679.2 ) — (257.3 ) (1,936.5 ) — Settlements (2) — (561.8 ) (68.0 ) (629.8 ) 368.8 Ending balance December 31, 2018 $ 15,531.1 $ 6,356.6 $ 913.0 $ 22,800.7 $ (2,608.0 ) (1) Includes purchases, contributions for joint ventures, capital expenditures, lending for loans receivable and assumption of loans payable. (2) Includes operating income for real estate joint ventures net of distributions, principal payments and payoffs of loans receivable, and principal payments and extinguishment of loans payable. (3) Amount shown is reflective of loans receivable and loans receivable with related parties. The following table shows quantitative information about unobservable inputs related to the Level 3 fair value measurements as of December 31, 2019 . Type Asset Class Valuation Technique(s) Unobservable Inputs Range (Weighted Average) Real Estate Properties and Joint Ventures Office Income Approach—Discounted Cash Flow Discount Rate 5.5%–8.5% (6.6%) Terminal Capitalization Rate 4.0%–7.5% (5.5%) Income Approach—Direct Capitalization Overall Capitalization Rate 3.9%–7.0% (5.0%) Industrial Income Approach—Discounted Cash Flow Discount Rate 5.3% - 9.0% (6.7%) Terminal Capitalization Rate 4.3% - 8.1% (5.5%) Income Approach—Direct Capitalization Overall Capitalization Rate 3.9% - 7.4% (4.9%) Residential Income Approach—Discounted Cash Flow Discount Rate 5.3% - 7.8% (6.4%) Terminal Capitalization Rate 4.3% - 6.8% (5.1%) Income Approach—Direct Capitalization Overall Capitalization Rate 3.8% - 6.0% (4.6%) Retail Income Approach—Discounted Cash Flow Discount Rate 5.3% - 11.7% (6.6%) Terminal Capitalization Rate 4.8% - 9.4% (5.4%) Income Approach—Direct Capitalization Overall Capitalization Rate 3.3% - 11.0% (4.9%) Hotel Income Approach—Discounted Cash Flow Discount Rate 10.0% (10.0%) Terminal Capitalization Rate 7.8% (7.8%) Income Approach—Direct Capitalization Overall Capitalization Rate 7.5% (7.5%) Loans Payable Office and Industrial Discounted Cash Flow Loan-to-Value Ratio 31.6% - 59.5% (46.3%) Equivalency Rate 3.1% - 4.3% (3.4%) Net Present Value Loan-to-Value Ratio 31.6% - 59.5% (46.3%) Weighted Average Cost of Capital Risk Premium Multiple 1.2 - 1.5 (1.3) Residential Discounted Cash Flow Loan-to-Value Ratio 30.2% - 69.0% (47.8%) Equivalency Rate 3.0% - 3.6% (3.3%) Net Present Value Loan-to-Value Ratio 30.2% - 69.0% (47.8%) Weighted Average Cost of Capital Risk Premium Multiple 1.2 - 1.7 (1.3) Retail Discounted Cash Flow Loan-to-Value Ratio 33.3% - 63.3% (41.1%) Equivalency Rate 3.3% - 4.0% (3.5%) Net Present Value Loan-to-Value Ratio 33.3% - 63.3% (41.1%) Weighted Average Cost of Capital Risk Premium Multiple 1.2 - 1.5 (1.3) Loans Receivable, including those with related parties Residential, Hotel, Industrial, Office, Retail and Storage Discounted Cash Flow Loan-to-Value Ratio 31.7% - 81.5% (72.5%) Equivalency Rate 3.2% - 8.4% (6.0%) The following table shows quantitative information about unobservable inputs related to the Level 3 fair value measurements as of December 31, 2018. Type Asset Class Valuation Technique(s) Unobservable Inputs Range (Weighted Average) Real Estate Properties and Joint Ventures Office Income Approach—Discounted Cash Flow Discount Rate 5.5%–8.6% (6.5%) Terminal Capitalization Rate 4.0%–7.5% (5.4%) Income Approach—Direct Capitalization Overall Capitalization Rate 4.0%–7.0% (4.8%) Industrial Income Approach—Discounted Cash Flow Discount Rate 5.3%–8.9% (6.8%) Terminal Capitalization Rate 4.4%–7.3% (5.5%) Income Approach—Direct Capitalization Overall Capitalization Rate 4.0%–7.0% (4.9%) Residential Income Approach—Discounted Cash Flow Discount Rate 5.5%–7.8% (6.5%) Terminal Capitalization Rate 3.8%–6.8% (5.0%) Income Approach—Direct Capitalization Overall Capitalization Rate 3.3%–6.0% (4.5%) Retail Income Approach—Discounted Cash Flow Discount Rate 5.0%–10.7% (6.4%) Terminal Capitalization Rate 4.3%–9.0% (5.3%) Income Approach—Direct Capitalization Overall Capitalization Rate 3.3%–8.5% (4.7%) Loans Payable Office and Industrial Discounted Cash Flow Loan-to-Value Ratio 36.4%–67.8% (47.6%) Equivalency Rate 3.9%–6.2% (4.6%) Net Present Value Loan-to-Value Ratio 36.4%–67.8% (47.6%) Weighted Average Cost of Capital Risk Premium Multiple 1.2–1.4 (1.3) Residential Discounted Cash Flow Loan-to-Value Ratio 31.9%–63.6% (48.1%) Equivalency Rate 3.4%–4.6% (4.1%) Net Present Value Loan-to-Value Ratio 31.9%–63.6% (48.1%) Weighted Average Cost of Capital Risk Premium Multiple 1.1–1.4 (1.2) Retail Discounted Cash Flow Loan-to-Value Ratio 31.9%–55.3% (39.3%) Equivalency Rate 4.3%–5.3% (4.5%) Net Present Value Loan-to-Value Ratio 31.9%–55.3% (39.3%) Weighted Average Cost of Capital Risk Premium Multiple 1.1–1.3 (1.2) Loans Receivable Residential, Industrial, Office, Retail and Storage Discounted Cash Flow Loan-to-Value Ratio 70.8%-79.2% (75.6%) Equivalency Rate 6.0%-8.3% (6.9%) Real Estate Properties and Joint Ventures: The significant unobservable inputs used in the fair value measurement of the Account’s real estate property and joint venture investments are the selection of certain investment rates (Discount Rate, Terminal Capitalization Rate, and Overall Capitalization Rate). Significant increases (decreases) in any of those inputs in isolation would result in significantly lower (higher) fair value measurements, respectively. Loans Payable: The significant unobservable inputs used in the fair value measurement of the Account’s loans payable are the loan-to-value ratios and the selection of certain credit spreads and weighted average cost of capital risk premiums. Significant increases (decreases) in any of those inputs in isolation would result in a significantly lower (higher) fair value, respectively. Loans Receivable: The significant unobservable inputs used in the fair value measurement of the Account’s loans receivable are the loan-to-value ratios and the selection of certain credit spreads. Significant increases (decreases) in any of those inputs in isolation would result in a significantly lower (higher) fair value, respectively. During the years ended December 31, 2019 and 2018 there were no transfers between Levels 1, 2 or 3. The amount of total net unrealized gains included in changes in net assets attributable to the change in net unrealized gains relating to Level 3 investments and loans payable using significant unobservable inputs still held as of the reporting date is as follows (millions): Real Estate Properties Real Estate Joint Ventures Loans Receivable Total Level 3 Investments Mortgage Loans Payable For the year ended December 31, 2019 $ 355.2 $ (94.7 ) $ (4.1 ) $ 256.4 $ (96.8 ) For the year ended December 31, 2018 $ 282.6 $ 80.8 $ 0.3 $ 363.7 $ 86.2

Investments in Joint Ventures

Investments in Joint Ventures	12 Months Ended
	Dec. 31, 2019
Equity Method Investments and Joint Ventures [Abstract]
Investments in Joint Ventures	Investments in Joint Ventures The Account owns interests in several real estate properties through joint ventures and receives distributions and allocations of profits and losses from the joint ventures based on the Account’s ownership interest in those investments. Several of these joint ventures have loans payable collateralized by the properties owned by the aforementioned joint ventures. At December 31, 2019 , the Account held investments in joint ventures with ownership interest percentages that ranged from 33.3% to 98.0% . Certain joint ventures are subject to adjusted distribution percentages when earnings in the investment reach a pre-determined threshold. A condensed summary of the gross financial position and results of operations of the combined joint ventures is shown below (millions): December 31, 2019 2018 Assets Real estate properties, at fair value $ 17,455.8 $ 16,134.1 Other assets 485.9 460.3 Total assets $ 17,941.7 $ 16,594.4 Liabilities & Equity Mortgage notes payable and other obligations, at fair value $ 5,185.3 $ 5,035.3 Other liabilities 256.3 262.5 Total liabilities 5,441.6 5,297.8 Total equity 12,500.1 11,296.6 Total liabilities and equity $ 17,941.7 $ 16,594.4 Years ended December 31, 2019 2018 2017 Operating Revenue and Expenses Revenues $ 1,126.5 $ 950.6 $ 869.2 Expenses 604.1 487.1 426.9 Excess of revenues over expenses $ 522.4 $ 463.5 $ 442.3

Investments in Real Estate Fund

Investments in Real Estate Funds	12 Months Ended
	Dec. 31, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Investments in Real Estate Funds	Investments in Real Estate Funds The Account has ownership interests in real estate funds ("Funds"). The Funds are setup as limited partnerships or entities similar to a limited partnership, and as such, meet the definition of a VIE as the limited partners (as a group) lack the power, through voting or similar rights, to direct the activities of the Fund that most significantly impact the Fund's economic performance. Management has determined that the Account is not the primary beneficiary for any of the Funds, as the Account lacks the power to direct the activities of the Fund that most significantly impact the Fund's economic performance, and the Account further lacks substantive kick-out rights to remove the entity with these powers. Refer to Note 1—Organization and Significant Accounting Policies for a description of the methodology used to determine the primary beneficiary of a VIE. No financial support (such as loans or financial guarantees) was provided to the Funds during the year ended December 31, 2019 . The Account is contractually obligated to make additional capital contributions in certain Funds in future years. These commitments are identified in Note 13—Commitments and Contingencies . The carrying amount and maximum exposure to loss relating to VIEs in which the Company holds a significant variable interest but is not the primary beneficiary and which have not been consolidated were as follows at December 31, 2019 . Fund Name Carrying Amount Maximum Exposure to Loss Liquidity Provisions Investment Strategy (in millions) LCS SHIP Venture I, LLC (90.0% Account Interest) $ 216.1 $ 216.1 Redemptions prohibited prior to liquidation. To invest in senior housing properties. Liquidation estimated to begin no earlier than 2025. The Account is permitted to sell or transfer its interest in the fund, subject to consent and approval of the manager. SP V - II, LLC (75.0% Account Interest) $ 23.3 $ 23.3 Redemptions prohibited prior to liquidation. To invest in medical office properties in the U.S. Liquidation estimated to begin no earlier than 2022. The Account is permitted to sell or transfer its interest in the fund, subject to consent and approval of the manager. Taconic New York City GP Fund, LP (60.0% Account Interest) $ 29.8 $ 29.8 Redemptions prohibited prior to liquidation. To invest in real estate and real estate-related assets in the New York City metropolitan statistical area ("MSA"). Liquidation estimated to begin no earlier than 2024. The Account is permitted to sell its interest in the fund, subject to consent and approval of the general partner. Veritas - Trophy VI, LLC (90.0% Account Interest) $ 4.2 $ 4.2 Redemptions prohibited prior to liquidation. To invest in multi-family properties primarily in the San Francisco Bay and Los Angeles MSA. The Account is not permitted to sell or transfer its interest in the fund until August 2022. After this date, the Account can sell or transfer its interest in the fund with the consent and approval of the manager. Fund Name Carrying Amount Maximum Exposure to Loss Liquidity Provisions Investment Strategy (in millions) IDR - Core Property Index Fund, LLC (2.0% Account Interest) $ 25.0 $ 25.0 Redemptions are permitted for a full calendar quarter and upon at least 90 days prior written notice, subject to fund availability. To invest primarily in open-ended funds that fall within the NFI-ODCE Index and are actively managed. The Account is permitted to sell its interest in the fund, subject to consent and approval of the manager. Grubb Southeast Real Estate Fund VI, LLC (67.0% Account Interest) $ 13.4 $ 13.4 Redemptions prohibited prior to liquidation. To acquire office investments across the Southeast. Liquidation estimated to begin no earlier than 2026. The Account is not permitted to sell or transfer its interest in the fund until June 2021. After this date, the Account can sell or transfer its interest in the fund with the consent and approval of the manager. Total $ 311.8 $ 311.8

Loans Receivable

Loans Receivable	12 Months Ended
	Dec. 31, 2019
Receivables [Abstract]
Loans Receivable	Loans Receivable The Account’s loan receivable portfolio is primarily comprised of mezzanine loans secured by the borrower’s indirect interest in commercial real estate. Mezzanine loans are subordinate to first mortgages on the underlying real estate collateral. The following property types represent the underlying real estate collateral for the Account's mezzanine loans (millions): December 31, 2019 December 31, 2018 Fair Value % Fair Value % Office (1) $ 768.0 48.8 % $ 512.1 56.2 % Industrial 199.6 12.7 % 176.4 19.3 % Retail 158.5 10.1 % 101.6 11.1 % Storage 82.0 5.2 % 63.2 6.9 % Apartments (1) 228.8 14.6 % 59.7 6.5 % Hotel 135.2 8.6 % — — % $ 1,572.1 100.0 % $ 913.0 100.0 % (1) Includes loans receivable with related parties. The Account monitors the risk profile of the loan receivable portfolio with the assistance of a third-party rating service that models the loans and assigns risk ratings based on information provided by TIAA, such as loan-to-value ratios, yields, credit quality of the borrowers, property types of the collateral, geographic and local market dynamics, physical condition of the collateral, and the underlying structure of the loans. Ratings for loans are updated monthly. Assigned ratings can range from AAA to C, with a AAA designation representing debt with the lowest level of credit risk and C representing a greater risk of default or principal loss. Mezzanine debt in good health is typically reflective of a risk rating in the B range (e.g., BBB, BB, B), as these ratings reflect borrowers' having adequate financial resources to service their financial commitments, but also acknowledging that adverse economic conditions, should they occur, would likely impede on a borrowers' ability to pay. The following table presents the fair values of the Account's loan portfolio based on the risk ratings as of December 31, 2019 , listed in order of the strength of the risk rating (from strongest to weakest): Number of Loans Fair Value % AA 1 48.3 3.1 % BBB 7 456.1 29.0 % BB 13 787.4 50.1 % B 3 205.0 13.0 % NR (1) 3 75.3 4.8 % 27 $ 1,572.1 100.0 % (1) "NR" designates loans not assigned an internal credit rating. As of December 31, 2019 , this is comprised of two loans with related parties and one loan to an unaffiliated entity. The loans are collateralized by equity interests in real estate investments. The Account had no loans in non-performing status as of December 31, 2019 .

Loans Payable

Loans Payable	12 Months Ended
	Dec. 31, 2019
Debt Disclosure [Abstract]
Loans Payable	Loans Payable At December 31, 2019 and 2018, the Account had outstanding loans payable secured by the following properties (millions): Property Interest Rate and Payment Frequency (2) Principal Amounts Outstanding as of December 31, Maturity 2019 2018 Mass Court 2.88% paid monthly $ — $ 90.2 September 1, 2019 Red Canyon at Palomino Park (4) 5.34% paid monthly 27.1 27.1 August 1, 2020 Green River at Palomino Park (4) 5.34% paid monthly 33.2 33.2 August 1, 2020 Blue Ridge at Palomino Park (4) 5.34% paid monthly 33.4 33.4 August 1, 2020 Ashford Meadows Apartments 5.17% paid monthly 44.6 44.6 August 1, 2020 The Knoll (1) 3.98% paid monthly 16.4 16.9 December 5, 2020 Ascent at Windward 3.51% paid monthly 34.6 34.6 January 1, 2022 The Palatine (1) 4.25% paid monthly 75.9 77.4 January 10, 2022 The Forum at Carlsbad (1) 4.25% paid monthly 85.7 87.3 March 1, 2022 Fusion 1560 3.42% paid monthly 37.4 37.4 June 10, 2022 San Diego Office Portfolio 3.62% paid monthly 48.2 — August 15, 2022 The Colorado (1) 3.69% paid monthly 88.1 89.9 November 1, 2022 The Legacy at Westwood (1) 3.69% paid monthly 44.9 45.8 November 1, 2022 Regents Court (1) 3.69% paid monthly 38.1 38.8 November 1, 2022 Fourth & Madison 3.75% paid monthly — 198.2 June 1, 2023 Fourth & Madison 4.17% paid monthly — 90.0 June 1, 2023 1001 Pennsylvania Avenue (1) 3.70% paid monthly 320.7 327.0 June 1, 2023 Biltmore at Midtown 3.94% paid monthly 36.4 36.4 July 5, 2023 Cherry Knoll 3.78% paid monthly 35.3 35.3 July 5, 2023 Lofts at SoDo 3.94% paid monthly 35.1 35.1 July 5, 2023 1401 H Street, NW 3.65% paid monthly 115.0 115.0 November 5, 2024 The District at La Frontera (1) 3.84% paid monthly 39.3 — December 1, 2024 The District at La Frontera (1) 4.96% paid monthly 4.4 — December 1, 2024 Circa Green Lake 3.71% paid monthly 52.0 52.0 March 5, 2025 Union - South Lake Union 3.66% paid monthly 57.0 57.0 March 5, 2025 Holly Street Village 3.65% paid monthly 81.0 81.0 May 1, 2025 Township Apartments 3.65% paid monthly — 49.0 May 1, 2025 Henley at Kingstowne 3.60% paid monthly 71.0 — May 1, 2025 32 South State Street 4.48% paid monthly 24.0 24.0 June 6, 2025 Vista Station Office Portfolio (1) 4.00% paid monthly 20.5 — July 1, 2025 780 Third Avenue 3.55% paid monthly 150.0 150.0 August 1, 2025 780 Third Avenue 3.55% paid monthly 20.0 20.0 August 1, 2025 Vista Station Office Portfolio (1) 4.20% paid monthly 44.7 — November 1, 2025 701 Brickell Avenue 3.66% paid monthly 184.0 184.0 April 1, 2026 55 Second Street 3.74% paid monthly — 137.5 October 1, 2026 1900 K Street, NW 3.93% paid monthly 163.0 163.0 April 1, 2028 99 High Street 3.90% paid monthly 277.0 277.0 March 1, 2030 Total Principal Outstanding $ 2,338.0 $ 2,688.1 Fair Value Adjustment (3) 27.0 (80.1 ) Total Loans Payable $ 2,365.0 $ 2,608.0 (1) The mortgage is adjusted monthly for principal payments. (2) Interest rates are fixed. Some mortgages held by the Account are structured to begin principal and interest payments after an initial interest only period. (3) The fair value adjustment consists of the difference (positive or negative) between the principal amount of the outstanding debt and the fair value of the outstanding debt. See Note 1—Organization and Significant Accounting Policies. (4) Represents mortgage loans on these individual properties which are held within the Palomino Park portfolio. Principal payment schedule on loans payable as of December 31, 2019 was as follows (millions): Amount 2020 $ 170.9 2021 19.7 2022 455.5 2023 418.2 2024 165.4 Thereafter 1,108.3 Total maturities $ 2,338.0

Line of Credit

Line of Credit	12 Months Ended
	Dec. 31, 2019
Debt Disclosure [Abstract]
Line of Credit	Line of Credit On September 20, 2018, the Account entered into a $500.0 million unsecured revolving credit agreement (“Line of Credit”) syndicated across four national banks (“Lenders”), with each Lender providing a $125.0 million commitment. Access to the Line of Credit expires on September 20, 2021, with an option to extend the Line of Credit for two consecutive twelve terms at the Account’s election. The Account may request an additional $250.0 million in commitments from the Lenders at any time; however, this request is subject to approval at the sole discretion of the Lenders and is not a guarantee that an expansion beyond the original $500.0 million commitment will be granted. Draws against the Line of Credit can take the form of Eurodollar Loans or Alternate Base Rate Loans (“ABR Loans”). Eurodollar Loans and ABR Loans both require a minimum funding of $5.0 million . The Account is charged a fee of 0.20% per annum on any unused portion of the Line of Credit. For the year ended December 31, 2019 , $1.0 million was charged to the Account for expenses related to the Line of Credit. Eurodollar Loans are issued for a term of twelve months or less and bear interest during the period (“Interest Period”) at a rate equal to the Adjusted London Interbank Offer Rate (“Adjusted LIBOR”) plus a spread ranging between 0.85% - 1.05% per annum (the “Applicable Rate”), with the spread dependent upon the leverage ratio of the Account. The Adjusted LIBOR Rate is calculated by multiplying the Statutory Reserve Rate, as determined by the Federal Reserve Board for Eurodollar liabilities, by the LIBOR rate, as determined by the Intercontinental Exchange on the date of issuance that corresponds to the length of the Interest Period of the Eurodollar Loan. The Account may prepay Eurodollar Loans at any time during the life of the loan without penalty. The Account is limited to five active Eurodollar Loans through the Line of Credit; however, the Account may retire and initiate new Eurodollar Loans without restriction so long as the total number of loans in active status never exceeds the limit. ABR Loans are issued for a specific length of time and bear interest at a rate equal to the highest rate among the following calculations plus the Applicable Rate: a) the Prime Rate on the date of issuance, with the Prime Rate being defined as the rate of interest last quoted by the Wall Street Journal as the Prime Rate; b) the Federal Reserve Bank of New York (“NYFRB”) Rate as provided by the NYFRB on the date of issuance plus 0.5% ; or c) the Adjusted LIBOR Rate plus 1.0% . The Account may prepay ABR Loans at any time during the life of the loan without penalty. As of December 31, 2019 , the Account had a $250.0 million loan outstanding on the Line of Credit. The Account is in compliance with all covenants required by the Line of Credit.

Financial Highlights

Financial Highlights	12 Months Ended
	Dec. 31, 2019
Condensed Financial Information Disclosure [Abstract]
Financial Highlights	Financial Highlights Selected condensed financial information for an Accumulation Unit of the Account is presented below. Per Accumulation Unit data is calculated on average units outstanding. Years ended December 31, 2019 2018 2017 2016 2015 Per Accumulation Unit Data: Rental income $ 18.165 $ 17.757 $ 17.132 $ 16.433 $ 15.538 Real estate property level expenses and taxes 8.734 8.548 7.722 7.534 7.319 Real estate income, net 9.431 9.209 9.410 8.899 8.219 Other income 6.752 6.162 4.762 3.594 3.342 Total income 16.183 15.371 14.172 12.493 11.561 Expense charges (1) 3.439 3.161 3.318 3.290 3.092 Investment income, net 12.744 12.210 10.854 9.203 8.469 Net realized and unrealized gain on investments and loans payable 10.262 6.877 5.839 9.660 18.911 Net increase in Accumulation Unit Value 23.006 19.087 16.693 18.863 27.380 Accumulation Unit Value: Beginning of period 417.416 398.329 381.636 362.773 335.393 End of period $ 440.422 $ 417.416 $ 398.329 $ 381.636 $ 362.773 Total return 5.51 % 4.79 % 4.37 % 5.20 % 8.16 % Ratios to Average net Assets: Expenses (1) 0.78 % 0.76 % 0.83 % 0.86 % 0.86 % Investment income, net 2.90 % 2.95 % 2.72 % 2.41 % 2.37 % Portfolio turnover rate: Real estate properties (2) 7.8 % 11.8 % 2.7 % 1.3 % 5.7 % Marketable securities (3) 28.7 % 5.1 % 5.7 % 3.5 % 10.0 % Accumulation Units outstanding at end of period (millions): 60.8 60.7 61.3 62.4 60.4 Net assets end of period (millions) $ 27,307.9 $ 25,842.6 $ 24,942.6 $ 24,304.7 $ 22,360.0 (1) Expense charges per Accumulation Unit and the Ratio of Expenses to average net assets reflect the year to date Account level expenses and exclude real estate property level expenses which are included in real estate income, net. (2) Real estate investment portfolio turnover rate is calculated by dividing the lesser of purchases or sales of real estate property investments (including contributions to, or return of capital distributions received from, existing joint venture and Funds investments) by the average value of the portfolio of real estate investments held during the period. (3) Marketable securities portfolio turnover rate is calculated by dividing the lesser of purchases or sales of securities, excluding securities having maturity dates at acquisition of one year or less, by the average value of the portfolio securities held during the period.

Accumulation Units

Accumulation Units	12 Months Ended
	Dec. 31, 2019
Accumulated Units Disclosure [Abstract]
Accumulation Units	Accumulation Units Changes in the number of Accumulation Units outstanding were as follows (millions): Years ended December 31, 2019 2018 2017 Outstanding: Beginning of period 60.7 61.3 62.4 Credited for premiums 6.2 6.5 6.6 Annuity, other periodic payments, withdrawals and death benefits (6.1 ) (7.1 ) (7.7 ) End of period 60.8 60.7 61.3

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2019
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Commitments —As of December 31, 2019 and 2018 , the Account had the following immediately callable commitments to purchase additional interests in its real estate funds or provide additional funding through its loan receivable investments: Commitment Expiration December 31, 2019 December 31, 2018 Real Estate Funds (1) Taconic New York City GP Fund 11/2020 $ 11.4 $ 26.0 LCS SHIP Venture I, LLC 12/2020 28.1 75.0 Veritas Trophy VI, LLC (2) 02/2020 35.8 — SP V - II, LLC 09/2022 74.9 — Grubb Southeast Real Estate Fund VI, LLC 06/2021 86.6 — JCR Capital - REA Preferred Equity Parallel Fund 12/2022 100.0 — Townsend Strategic Ventures LP 03/2021 250.0 — 586.8 101.0 Loans Receivable (3) 311 South Wacker Mezzanine 06/2020 7.6 11.9 Rosemont Towson Mezzanine 09/2022 1.2 2.3 1330 Broadway Mezzanine 09/2022 14.0 14.8 SCG Oakland Portfolio Mezzanine 03/2021 7.0 — BREP VIII Industrial Mezzanine 03/2026 14.1 — San Diego Office Portfolio Senior Loan 08/2022 10.0 — San Diego Office Portfolio Mezzanine 08/2022 3.3 — MRA Hub 34 Holding, LLC 09/2022 1.5 — Liberty Park Mezzanine 11/2023 5.0 — Colony New England Hotel Portfolio Senior Loan 11/2022 14.1 — Colony New England Hotel Portfolio Mezzanine 11/2022 4.7 — Exo Apartments Senior Loan 06/2020 7.1 — Exo Apartments Mezzanine 06/2020 2.4 — 92.0 29.0 TOTAL COMMITMENTS $ 678.8 $ 130.0 (1) Additional capital can be called during the commitment period at any time. The commitment period can only be extended by the manager with the consent of the Account. The commitment expiration date is reflective of the most recent signed agreement between the Account and the fund manager, including any side letter agreements. (2) The fund manager is granted 18 months from the initial contribution date, August 2019, to make its first capital call. If none have occurred, the Account's commitment will be reduced by $15.0 million . If a capital call occurs during the initial 18 month window, the commitment period will be modified to three years from the first capital call date. (3) Additional advances from the Account can be requested during the commitment period at any time. The commitment expiration date is reflective of the most recent signed agreement between the Account and the borrower, including any side letter agreements. Certain loans contain extension clauses on the term of the loan that do not require the Account's prior consent. If elected, the Account's commitment may be extended through the extension term. Contingencies —In the normal course of business, the Account may be named, from time to time, as a defendant or may be involved in various legal actions, including arbitrations, class actions and other litigation. The Account establishes an accrual for all litigation and regulatory matters when it believes it is probable that a loss has been incurred and the amount of the loss can be reasonably estimated. Once established, accruals are adjusted, as appropriate, in light of additional information. The amount of loss ultimately incurred in relation to those matters may be higher or lower than the amounts accrued for those matters. As of the date of this report, management of the Account does not believe that the results of any such claims or litigation, individually or in the aggregate, will have a material effect on the Account’s business, financial position or results of operations.

Subsequent Events

Subsequent Events	12 Months Ended
	Dec. 31, 2019
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events Real Estate Properties and Joint Ventures Purchases Property Name Transaction Date Ownership Percentage Sector Location Net Purchase Price (1) Sole at City Center 01/15/2020 100.00% Apartments West Palm Beach, FL $ 103.6 Park Creek Apartments 02/10/2020 100.00% Apartments Fort Worth, TX 41.7 Warwick Shopping Center (2) 02/19/2020 100.00% Retail Warwick, RI 11.1 Overlook at King of Prussia (2) 02/19/2020 100.00% Retail King of Prussia, PA 55.1 Shoppes at Lake Mary (2) 02/19/2020 100.00% Retail Lake Mary, FL 21.0 Winslow Bay Commons (2) 02/19/2020 100.00% Retail Mooresville, NC 50.9 Bellevue Place (2) 02/19/2020 100.00% Retail Nashville, TN 7.8 Eisenhower Crossing (2) 02/19/2020 100.00% Retail Macon, GA 10.1 Pavilion at Turkey Creek (2) 02/19/2020 100.00% Retail Knoxville, TN 49.9 Town and Country (2) 02/19/2020 100.00% Retail Knoxville, TN 30.1 Creeks at Virginia Center (2) 02/19/2020 100.00% Retail Glen Allen, VA 41.7 Alexander Place (2) 02/19/2020 100.00% Retail Raleigh, NC 39.9 Market Square (2) 02/19/2020 100.00% Retail Ft. Myers, FL 20.4 Cypress Trace (2) 02/19/2020 100.00% Retail Ft. Myers, FL 39.7 Columbiana Station (2) 02/19/2020 100.00% Retail Columbia, SC 43.8 Village Crossing (2) 02/19/2020 100.00% Retail Skokie, IL 160.7 Birkdale Village (2) 02/19/2020 100.00% Retail Huntersville, NC 128.9 Birkdale Village Apartments (2) 02/19/2020 100.00% Apartments Huntersville, NC 70.8 River Ridge (2) 02/19/2020 100.00% Retail Birmingham, AL 28.0 Woodstock Square (2) 02/19/2020 100.00% Retail Woodstock, GA 33.7 Newnan Pavilion (2) 02/19/2020 100.00% Retail Newnan, GA 39.7 Marketplace at Mill Creek (2) 02/19/2020 100.00% Retail Buford, GA 71.5 Heritage Pavilion (2) 02/19/2020 100.00% Retail Smyrna, GA 41.6 Fayette Pavilion (2) 02/19/2020 100.00% Retail Fayetteville, GA 88.4 Pacific City (3) 03/09/2020 100.00% Retail Huntington Beach, CA 153.9 (1) The net purchase price represents the purchase price and closing costs. (2) On February 19, 2020, the Account purchased the 15% ownership interest of SITE Centers Corp in DDRTC Core Retail Fund, LLC, a joint venture between the Account and SITE Centers Corp. All properties and associated debt formerly held within DDRTC Core Retail Fund, LLC are now wholly-owned by the Account. (3) On March 9, 2020, the Account purchased the 30% ownership interest of DJM Capital in PC Borrower, LLC, a joint venture between the Account and DJM Capital. The retail property and associated debt formerly held within PC Borrower, LLC is now wholly-owned by the Account. Sales Property Name Transaction Date Ownership Percentage Sector Location Net Sales Price (1) Realized Gain(Loss) on Sale (2) The Woodley 01/08/2020 100.00% Apartments Washington, D.C. $ 176.7 $ (25.2 ) Beltway North Commerce Center 01/14/2020 100.00% Industrial Houston, TX 29.8 4.3 250 North 10th Street 01/15/2020 100.00% Apartments Brooklyn, NY 137.1 (37.6 ) DDRTC Core Retail Fund, LLC (3) 02/19/2020 85.00% Retail Various, U.S.A. 932.8 (422.2 ) PC Borrower, LLC (4) 03/09/2020 70.00% Retail Huntington Beach, CA 107.7 (31.3 ) (1) The net sales price represents the sales price, less selling expenses. (2) Majority of the realized gain(loss) has been previously recognized as unrealized gains(losses) in the Account's Consolidated Statements of Operations. (3) On February 19, 2020, the Account purchased the 15% ownership interest of SITE Centers Corp in DDRTC Core Retail Fund, LLC, a joint venture between the Account and SITE Centers Corp. All properties and associated debt formerly held within DDRTC Core Retail Fund, LLC are now wholly-owned by the Account. (4) On March 9, 2020, the Account purchased the 30% ownership interest of DJM Capital in PC Borrower, LLC, a joint venture between the Account and DJM Capital. The retail property and associated debt formerly held within PC Borrower, LLC is now wholly-owned by the Account. Loans Receivable Originations and purchases Investment Name Transaction Date Interest Rate Sector Maturity Date Location Amount Sol Y Luna 01/07/2020 6.55% Apartments 01/06/2030 Tucson, AZ $ 53.0 Payoffs and sales Investment Name Transaction Date Interest Rate Sector Maturity Date Location Amount Crest at Las Colinas Station Mezzanine 01/30/2020 5.11% + LIBOR Apartments 05/10/2021 Irving, TX $ 20.0 DJM Capital Partners Mezzanine 03/09/2020 5.00% Retail 03/02/2020 Huntington Beach, CA 6.3 Financings New financings and assumptions of debt Property Name Transaction Date Ownership Percentage Interest Rate Sector Maturity Date Location Amount Overlook at King of Prussia (1) 02/19/2020 100.00% 3.82% Retail 09/11/2027 King of Prussia, PA $ 40.8 Winslow Bay Commons (1) 02/19/2020 100.00% 3.82% Retail 09/11/2027 Mooresville, NC 25.8 Birkdale Village (1) 02/19/2020 100.00% 4.30% Retail 04/01/2024 Huntersville, NC 78.4 Marketplace at Mill Creek (1) 02/19/2020 100.00% 3.82% Retail 09/11/2027 Buford, GA 39.6 Pacific City (2) 03/09/2020 100.00% 2.00% + LIBOR Retail 10/01/2023 Huntington Beach, CA 105.0 Payoffs and assignments of debt Property Name Transaction Date Ownership Percentage Interest Rate Sector Maturity Date Location Amount DDRTC Core Retail Fund, LLC (1) 02/19/2020 85.00% Various Retail Various Various, U.S.A. $ 156.8 PC Borrower, LLC (2) 03/09/2020 70.00% 2.00% + LIBOR Retail 10/01/2023 Huntington Beach, CA 73.5 (1) On February 19, 2020, the Account purchased the 15% ownership interest of SITE Centers Corp in DDRTC Core Retail Fund, LLC, a joint venture between the Account and SITE Centers Corp. All properties and associated debt formerly held within DDRTC Core Retail Fund, LLC are now wholly-owned by the Account. (2) On March 9, 2020, the Account purchased the 30% ownership interest of DJM Capital in PC Borrower, LLC, a joint venture between the Account and DJM Capital. The retail property and associated debt formerly held within PC Borrower, LLC is now wholly-owned by the Account. Financings - Other On January 21, 2020, the Account paid off the $250.0 million loan outstanding on the Line of Credit. Marketable Securities In the first two months of 2020, the Account sold approximately $304 million in real estate-related securities.

Organization and Significant _2

Organization and Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2019
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation: The accompanying Consolidated Financial Statements include the Account and those subsidiaries wholly-owned by TIAA for the benefit of the Account. All significant intercompany accounts and transactions between the Account and such subsidiaries have been eliminated. The Accumulation Unit Value (“AUV”) used for financial reporting purposes may differ from the AUV used for processing transactions. The AUV used for financial reporting purposes includes security and participant transactions effective through the period end date to which this report relates. Total return is computed based on the AUV used for processing transactions.
Determination of Investments at Fair Value	Determination of Investments at Fair Value: The Account reports all investments at fair value in accordance with the Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC”) 946, Financial Services—Investment Companies. Further in accordance with the adoption of the fair value option allowed under ASC 825, Financial Instruments , and at the election of Account management, loans payable and a line of credit are reported at fair value. The FASB has defined fair value as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants excluding transaction costs. The following is a description of the valuation methodologies used to determine the fair value of the Account’s investments and investment related loans payable. Valuation of Real Estate Properties —Investments in real estate properties are stated at fair value, as determined in accordance with policies and procedures reviewed by the Investment Committee of the Board and in accordance with the responsibilities of the Board as a whole. Accordingly, the Account does not record depreciation. Determination of fair value involves significant levels of judgment because the actual fair value of real estate can be determined only by negotiation between the parties in a sales transaction. The Account’s primary objective when valuing its real estate investments will be to produce a valuation that represents a reasonable estimate of the fair value of its investments. Implicit in the Account’s definition of fair value are the consummation of a sale as of a specified date and the passing of title from seller to buyer under conditions whereby: • Buyer and seller are typically motivated; • Both parties are well informed or well advised, and acting in what they consider their best interests; • A reasonable time is allowed for exposure in the open market; • Payment is made in terms of cash or in terms of financial arrangements comparable thereto; and • The price represents the normal consideration for the property sold unaffected by special or creative financing or sales concessions granted by anyone associated with the sale. Property and investment values are affected by, among other things, the availability of capital, occupancy rates, rental rates, and interest and inflation rates. As a result, determining real estate and investment values involves many assumptions. Key inputs and assumptions include rental income and expense amounts, related rental income and expense growth rates, capital expenditures, discount rates and capitalization rates. Valuation techniques include discounted cash flow analysis, prevailing market capitalization rates or multiples applied to earnings from the property, analysis of recent comparable sales transactions, actual sale negotiations and bona fide purchase offers received from third parties. Amounts ultimately realized from each investment may vary significantly from the fair value presented. Real estate properties owned by the Account are initially valued based on an independent third party appraisal, as reviewed by TIAA’s internal appraisal staff and as applicable by the Account’s independent fiduciary at the time of the closing of the purchase. Such initial valuation may result in a potential unrealized gain or loss reflecting the difference between an investment’s fair value (i.e., exit price) and its cost basis (which is inclusive of transaction costs). Subsequently, each property is appraised each quarter by an independent third party appraiser, reviewed by TIAA’s internal appraisal staff and as applicable the Account’s independent fiduciary. In general, the Account obtains appraisals of its real estate properties spread out throughout the quarter, which is intended to result in appraisal adjustments, and thus, adjustments to the valuations of its holdings (to the extent such adjustments are made) that happen regularly throughout each quarter and not on one specific day or month in each period. Further, management reserves the right to order an appraisal and/or conduct another valuation outside of the normal quarterly process when facts or circumstances at a specific property change. For example, under certain circumstances a valuation adjustment could be made when the account receives a bona fide bid for the sale of a property held within the Account or one of the Account’s joint ventures. Adjustments may be made for events or circumstances indicating an impairment of a tenant’s ability to pay amounts due to the Account under a lease (including due to a bankruptcy filing of that tenant). Alternatively, adjustments may be made to reflect the execution or renewal of a significant lease. Also, adjustments may be made to reflect factors (such as sales values for comparable properties or local employment rate) bearing uniquely on a particular region in which the Account holds properties. TIAA’s internal appraisal staff oversees the entire appraisal process, in conjunction with the Account’s independent fiduciary (the independent fiduciary is more fully described in the following paragraph). Any differences in the conclusions of TIAA’s internal appraisal staff and the independent appraiser will be reviewed by the independent fiduciary, which will make a final determination on the matter (which may include ordering a subsequent independent appraisal). The independent fiduciary, RERC, LLC, has been appointed by a special subcommittee of the Investment Committee of the Board to, among other things, oversee the appraisal process. The independent fiduciary must approve all independent appraisers used by the Account. All appraisals are performed in accordance with Uniform Standards of Professional Appraisal Practices, the real estate appraisal industry standards created by The Appraisal Foundation. Real estate appraisals are estimates of property values based on a professional’s opinion. Appraisals of properties held outside of the U.S. are performed in accordance with industry standards commonly applied in the applicable jurisdiction. These independent appraisers are always expected to be MAI-designated members of the Appraisal Institute (or its European equivalent, Royal Institute of Chartered Surveyors) and state certified appraisers from national or regional firms with relevant property type experience and market knowledge. Under the Account’s current procedures, each independent appraisal firm will be rotated off of a particular property at least every three years, although such appraisal firm may perform appraisals of other Account properties subsequent to such rotation. Also, the independent fiduciary can require additional appraisals if factors or events have occurred that could materially change a property’s value (including those identified above) and such change is not reflected in the quarterly valuation review, or otherwise to ensure that the Account is valued appropriately. The independent fiduciary must also approve any valuation change of real estate-related assets where a property’s value changed by more than 6% from the most recent independent annual appraisal, or if the value of the Account would change by more than 4% within any calendar quarter or more than 2% since the prior calendar month. When a real estate property is subject to a mortgage, the property is valued independently of the mortgage and the property and mortgage fair values are reported separately (see Valuation of Loans Payable ). The independent fiduciary reviews and approves all mortgage valuation adjustments before such adjustments are recorded by the Account. The Account continues to use the revised value for each real estate property and loan payable to calculate the Account’s daily net asset value until the next valuation review or appraisal. Valuation of Real Estate Joint Ventures —Real estate joint ventures are stated at the fair value of the Account’s ownership interests of the underlying entities. The Account’s ownership interests are valued based on the fair value of the underlying real estate, any related loans payable, and other factors, such as ownership percentage, ownership rights, buy/sell agreements, distribution provisions and capital call obligations. The fair value of real estate and loans payable held by joint ventures is determined in the same manner described above in Valuation of Real Estate Properties. The independent fiduciary reviews and approves all valuation adjustments before such adjustments are recorded by the Account. Upon the disposition of all real estate investments by an investee entity, the Account will continue to state its equity in the remaining net assets of the investee entity during the wind down period, if any, which occurs prior to the dissolution of the investee entity. Valuation of Real Estate Funds —Real estate fund interests are stated at the fair value of the Account’s ownership in the fund. Management uses net asset value information provided by limited partners as a practical expedient to estimate fair value. The Account receives estimates from limited partners on a quarterly basis, and audited information is provided annually. Upon receipt of the information, management reviews and concludes on whether the net asset values provided are an appropriate representation of the fair value of the Account's interests in the real estate funds and makes valuation adjustments as necessary. Valuation of real estate funds proceeds under the direction of the Investment Committee of the Board and in accordance with the responsibilities of the Board as a whole. Valuation of Marketable Securities —Equity securities listed or traded on any national market or exchange are valued at the last sale price as of the close of the principal securities market or exchange on which such securities are traded or, if there is no sale, at the mean of the last bid and asked prices on such market or exchange, exclusive of transaction costs. Valuation of Debt Securities —Debt securities with readily available market quotations, other than money market instruments, are generally valued at the most recent bid price or the equivalent quoted yield for such securities (or those of comparable maturity, quality and type). Debt securities for which market quotations are not readily available, are valued at fair value as determined by management and the Investment Committee of the Board and in accordance with the responsibilities of the Board as a whole. Short-term investments are valued in the same manner as debt securities, as described above. Money market instruments are valued at amortized cost, which approximates fair value. Valuation of Loans Receivable (i.e. the Account as a creditor) —Loans receivable are stated at fair value and are initially valued at the face amount of the loan funding. Subsequently, loans receivable are valued at least quarterly by TIAA’s internal valuation department based on market factors, such as market interest rates and spreads for comparable loans, the liquidity for loans of similar characteristics, the performance of the underlying collateral (such as the loan-to-value ratio and the cash flow of the underlying collateral) and the credit quality of the counterparty. The independent fiduciary reviews and approves all loan receivable valuation adjustments before such adjustments are recorded by the Account. The Account continues to use the revised value for each loan receivable to calculate the Account’s daily net asset value until the next valuation review. Valuation of Loans Payable (i.e. the Account as a debtor) —Mortgage or other loans payable, including the Accounts line of credit, are stated at fair value. The estimated fair value of loans payable is generally based on the amount at which the liability could be transferred in a current transaction, exclusive of transaction costs. Fair values are estimated based on market factors, such as market interest rates and spreads on comparable loans, the liquidity for loans of similar characteristics, the performance of the underlying collateral (such as the loan-to-value ratio and the cash flow of the underlying collateral), the maturity date of the loan, the return demands of the market, and the credit quality of the Account. Different assumptions or changes in future market conditions could significantly affect estimated fair values. At times, the Account may assume debt in connection with the purchase of real estate (including under the Account's line of credit or additional credit facilities). The independent fiduciary reviews and approves all valuation adjustments before such adjustments are recorded by the Account.
Accumulation and Annuity Funds	Accumulation and Annuity Funds: The accumulation fund represents the net assets attributable to participants in the accumulation phase of their investment (“Accumulation Fund”). The annuity fund represents the net assets attributable to the participants currently receiving annuity payments (“Annuity Fund”). The net increase or decrease in net assets from investment operations is apportioned between the accounts based upon their relative daily net asset values. Once an Account participant begins receiving lifetime annuity income benefits, payment levels cannot be reduced as a result of the Account’s actual mortality experience. In addition, the contracts pursuant to which the Account is offered are required to stipulate the maximum expense charge for all Account level expenses that can be assessed, which is not to exceed 2.5% of average net assets per year. The Account pays a fee to TIAA to assume mortality and expense risks.
Accounting for Investments	Accounting for Investments: The investments held by the Account are accounted for as follows: Real Estate Properties —Rent from real estate properties consists of all amounts earned under tenant operating leases, including base rent, recoveries of real estate taxes and other expenses and charges for miscellaneous services provided to tenants. Rental income is recognized in accordance with the billing terms of the lease agreements. The Account bears the direct expenses of the real estate properties owned. These expenses include, but are not limited to, fees to local property management companies, property taxes, utilities, maintenance, repairs, insurance, and other operating and administrative costs. An estimate of the net operating income earned from each real estate property is accrued by the Account on a daily basis and such estimates are adjusted when actual operating results are determined. Real Estate Joint Ventures —The Account has ownership interests in various real estate joint ventures (collectively, the “joint ventures”). The Account records its contributions as increases to its investments in the joint ventures, and distributions from the joint ventures are treated as income within income from real estate joint ventures and limited partnerships in the Account’s Consolidated Statements of Operations. Distributions that are identified as returns of capital are recorded as a reduction to the cost basis of the investment, whereas distributions identified as capital gains or losses are recorded as realized gains or losses. Income distributions from the joint ventures are recorded based on the Account’s proportional interest of the income distributed by the joint ventures. Income and losses incurred but not yet distributed or realized from the Account by the joint ventures are recorded as unrealized gains and losses. Real Estate Funds —The Account has limited ownership interests in various private real estate funds. The Account records its contributions as increases to the investments, and distributions from the investments are treated as income within income from real estate joint ventures and funds in the Account’s Consolidated Statements of Operations. Distributions that are identified as returns of capital are recorded as a reduction to the cost basis of the investment, whereas distributions identified as capital gains or losses are recorded as realized gains or losses. Unrealized gains and losses are recorded based upon the changes in the net asset values of the real estate funds as determined from the financial statements of the real estate funds when received by the Account. Prior to the receipt of the financial statements from the real estate funds, the Account estimates the value of its interest using information provided by the limited partners. Changes in value based on such estimates are recorded by the Account as unrealized gains and losses. Marketable Securities —Transactions in marketable securities are accounted for as of the date the securities are purchased or sold (trade date). Interest income is recorded as earned. Dividend income is recorded on the ex-dividend date within dividend income. Dividends that are identified as returns of capital are recorded as a reduction to the cost basis of the investment, whereas dividends identified as capital gains or losses are recorded as realized gains or losses. Realized gains and losses on securities transactions are accounted for on the specific identification method. Loans Receivable —The Account may originate, purchase or sell loans collateralized by real estate. The cost basis of originated loans is comprised of the principal balance and direct costs incurred that represent a component of loan’s reported fair value. The cost basis of purchased loans consists of the purchase price of the loan and additional direct costs incurred that represent a component of the loan’s reported fair value. Additional costs incurred by the Account to originate or purchase loans that do not represent a component of a loan’s fair value are recorded as expenses in the period incurred. Nonrefundable origination fees paid by borrowers are recognized as interest income once all activities required to execute the loan are completed. Prepayment fees received from the payoff of loans in advance of their maturity date are recognized as interest income on the date the payoff occurs. Interest income from loans in accrual status is recognized based on the current coupon rate of the loans. Interest income from loans in accrual status is recognized based on the current coupon rate of the loans. Interest income accruals are suspended when a loan becomes a non-performing loan, defined as a loan more than ninety days in arrears or at any point when management believes the full collection of principal is doubtful. Interest income on non-performing loans is recognized only as cash payments are received. Loans can be rehabilitated to normal accrual status once all past due interest has been collected and management believes the full collection of principal is likely. Realized and Unrealized Gains and Losses —Realized gains and losses are recorded at the time an investment is sold or a distribution is received in relation to an investment sale from a joint venture or fund. Real estate and loan receivable transactions are accounted for as of the date on which the purchase or sale transactions close (settlement date). The Account recognizes a realized gain on the sale of an investment to the extent that the contract sales price exceeds the cost-to-date of the investment being sold. A realized loss occurs when the cost-to-date exceeds the sales price. Realized gains and losses from partial sales of non-financial assets are recognized in accordance with ASC 610-20 - Gains and Losses from the Derecognition of Nonfinancial Assets . Realized gains and losses from the sale of financial assets are recognized in accordance with ASC 860 - Transfers and Servicing . Unrealized gains and losses are recorded as the fair values of the Account’s investments are adjusted, and as discussed within the Real Estate Joint Ventures, Real Estate Funds and Loans Receivable sections above. Net Assets —The Account’s net assets as of the close of each valuation day are valued by taking the sum of: • the value of the Account’s cash; cash equivalents, and short-term and other debt instruments; • the value of the Account’s other securities and other non-real estate assets; • the value of the individual real properties (based on the most recent valuation of that property) and other real estate-related investments owned by the Account; • an estimate of the net operating income accrued by the Account from its properties, other real estate-related investments and non-real estate-related investments (including short-term marketable securities) since the end of the prior valuation day; and • actual net operating income earned from the Account’s properties, other real estate-related investments and non-real estate-related investments (but only to the extent any such item of income differs from the estimated income accrued for on such investments), and then reducing the sum by liabilities held within the Account, including the daily investment management fee, administration and distribution fees, mortality and expense fee, liquidity guarantee fee, and certain other expenses attributable to operating the Account. Daily estimates of net operating income are adjusted to reflect actual net operating income on a monthly basis, at which time such adjustments (if any) are reflected in the Account’s unit value. After the end of every quarter, the Account reconciles the amount of expenses deducted from the Account (which is established in order to approximate the costs that the Account will incur) with the expenses the Account actually incurred. If there is a difference, the Account adds it to or deducts it from the Account in equal daily installments over the remaining days of the following quarter. Material differences may be repaid in the current calendar quarter. The Account’s at-cost deductions are based on projections of Account assets and overall expenses, and the size of any adjusting payments will be directly affected by the difference between management’s projections and the Account’s actual assets or expenses.
Variable Interest Entities	Variable Interest Entities: Variable interests are financial relationships which expose a reporting entity to the risks and rewards of variability in the entity's assets and operations. When variable interests exist, they are subject to evaluation under the variable interest entity ("VIE") model if any one of the following four characteristics are present: a) the entity is insufficiently capitalized; b) the equity holders do not have power to control the activities that most significantly impact the entity's financial performance; c) the voting rights of the equity holders are not proportionate to their economic interests; or d) the equity holders are not exposed to the residual losses or benefits that would normally be associated with equity interests. ASC 810 - Consolidation prohibits a reporting entity that qualifies as an investment company under ASC 946 - Financial Services - Investment Companies from consolidating an investee that is not an investment company. This scope exception does not apply to situations in which an investment company has an interest in another investment company. Accordingly, the Account's investments in other investment companies (e.g., real estate funds) are subject to evaluation under the VIE model. The Account consolidates a VIE if it concludes that the Account is the primary beneficiary of the VIE. The primary beneficiary has both: a) the power to direct the activities of a VIE that most significantly impact the VIE's economic performance; and b) the obligation to absorb losses or the right to receive benefits that could potentially be significant to the VIE. The following activities have been identified by the Account as having the most significant impact on a VIE's economic performance: • control over the ability to acquire and dispose of investments held by the entity; • the ability to kick out a managing entity without cause, either unilaterally or with a group of equity investors; • the ability to modify the power of the managing entity without its consent; and • control over the day-to-day decision making of the underlying investments An equity investor in a VIE may not actively be involved in the significant activities (i.e., it may cede day-to-day decision making to a third party), but if the equity investor has approval rights or some other mechanism to retain ultimate control, the equity investor with these rights would be concluded as having power over the activity. On a quarterly basis, the Account evaluates all involvements with VIEs, including any changes to governing powers of continuing VIEs. The consolidation status of VIEs may change as a result of such continued evaluation.
Cash and Cash Equivalents	Cash and Cash Equivalents: Cash and cash equivalents are balances held by the Account in bank deposit accounts which, at times, exceed federally insured limits. The Account’s management monitors these balances to mitigate the exposure of risk due to concentration and has not experienced any losses from such concentration.
Other Assets and Other Liabilities	Other Assets and Other Liabilities: Other assets and other liabilities consist of operating assets and liabilities utilized and held at each individual real estate property investment. Other assets consist of, amongst other items, cash, tenant receivables and prepaid expenses; whereas other liabilities primarily consist of security deposits. Other assets also include cash collateral held for securities on loan.
Federal Income Taxes	Federal Income Taxes: Based on provisions of the Internal Revenue Code, Section 817, the Account is taxed as a segregated asset account of TIAA and as such, the Account incurs no material federal income tax attributable to the net investment activity of the Account. The Account’s federal income tax return is generally subject to examination for a period of three years after filed. State and local tax returns may be subject to examination for an additional period of time depending on the jurisdiction. Management has analyzed the Account’s tax positions taken for all open federal income tax years and has concluded that no provision for federal income tax is required in the Account’s Consolidated Financial Statements.
Restricted Cash	Restricted Cash: The Account held restricted cash in escrow accounts for security deposits, as required by certain states, as well as property taxes, insurance, and various other property related matters as required by certain creditors related to outstanding loans payable collateralized by certain real estate investments. These amounts are recorded within other assets on the Consolidated Statements of Assets and Liabilities.
Changes In Net Assets	Changes in Net Assets: Premiums include premiums paid by existing accumulation unit holders in the Account and transfers into the Account. Withdrawals and death benefits include withdrawals out of the Account which include transfers out of the Account and required minimum distributions.
Due to/from Investment Manager	Due to/from Investment Manager: Due to/from investment manager represents amounts that are to be paid or received by TIAA on behalf of the Account. Amounts generally are paid or received by the Account within one or two business days and no interest is contractually charged on these amounts.
Securities Lending	Securities Lending: The Account may lend securities to qualified borrowers to earn additional income. The Account receives cash collateral against the loaned securities and maintains cash collateral in an amount not less than 100% of the market value of loaned securities during the period of the loan; any additional collateral required due to changes in security values is delivered to the Account the next business day. Cash collateral received by the Account is invested exclusively in an interest-bearing deposit account. The value of the loaned securities and the liability to return the cash collateral received are reflected in the Consolidated Statements of Assets and Liabilities. When loaning securities, the Account retains the benefits of owning the securities, including the economic equivalent of dividends or interest generated by the securities. All income generated by the securities lending program is reflected within interest income on the Consolidated Statements of Operations. Securities lending transactions are for real-estate related equity securities, and the resulting loans are continuous, can be recalled at any time, and have no set maturity. Securities lending income recognized by the Account consists of interest earned on cash collateral and lending fees, net of any rebates to the borrower and compensation to the agent. Such income is reflected within interest income on the Consolidated Statements of Operations. In lending its securities, the Account bears the market risk with respect to the investment of collateral and the risk that the agent may default on its contractual obligations to the Account. The agent bears the risk that the borrower may default on its obligation to return the loaned securities as the agent is contractually obligated to indemnify the Account if at the time of a default by a borrower some or all of the loan securities have not been returned.
Adopted Accounting Pronouncements	Adopted Accounting Pronouncements: In February 2016, the FASB issued Accounting Standards Update 2016-02 Leases (Topic 842) (“ASU 2016-02”) which supersedes Topic 840, Leases. ASU 2016-02 applies to all entities that enter into leases. Lessees are required to report assets and liabilities that arise from leases. Lessor accounting has largely remained unchanged; however, certain refinements were made to conform with revenue recognition guidance in the FASB issued Accounting Standards Update 2014-09, Revenue from Contracts with Customers ("ASU 2014-09"), specifically related to the allocation and recognition of contract consideration earned from lease and non-lease revenue components. ASU 2016-02 contains certain practical expedients, which the Account has elected. The Account's exposure to ASU 2016-02 is primarily as a lessor. The Account's exposure to ASU 2016-02 from the perspective of a lessee is limited to ground leases. The Account adopted ASU 2016-02 as of January 1, 2019. New disclosures required by ASC 2016-02 are included in the Notes to the Consolidated Financial Statements, refer to Note 4—Leases . The Account has elected the transition package of practical expedients permitted within the new standard. This practical expedient permits the Account to carryforward the historical lease classification and not to reassess initial direct costs for any existing leases. In addition, the Account has elected the practical expedient that allows lessors to avoid separating lease and non-lease components within a contract if certain criteria are met. The lessor’s practical expedient election is limited to circumstances in which (i) the timing and pattern of revenue recognition are the same for the non-lease component and the related lease component and (ii) the combined single lease component would be classified as an operating lease. This practical expedient allows the Account the ability to combine the lease and non-lease components if the underlying asset meets the two criteria above. In August 2018, FASB issued ASU 2018-13, Fair Value Measurement: Disclosure Framework - Changes to the Disclosure Requirements for Fair Value Measurements ("ASU 2018-13"). ASU 2018-13 modifies the disclosures required for fair value measurements. This guidance is effective for fiscal years beginning after December 15, 2019. The Account adopted ASU 2018-13 as of January 1, 2019 and concluded that the adoption did not have a material impact on the Notes to the Financial Statements. In February 2019, the FASB issued ASU 2019-01, Leases (Topic 842) Codification Improvements (“ASU 2019-01”). ASU 2019-01 addresses two lessor implementation issues and clarifies an exemption for lessors and lessees from a certain interim disclosure requirement associated with adopting the new lease accounting standard. This guidance is effective for fiscal years beginning after December 15, 2019 and interim periods within those fiscal years. The Account adopted ASU 2019-01 as of January 1, 2019 and concluded that the adoption did not have a material impact on the Consolidated Financial Statements.

Related Party Transactions (Tab

Related Party Transactions (Tables)	12 Months Ended
	Dec. 31, 2019
Related Party Transactions [Abstract]
Schedule of Key Terms of the Loans	The following table presents the key terms of the loans as of the reporting date: Related Party Equity Ownership Interest Interest Rate Maturity Date Fair Value at Principal December 31, 2019 December 31, 2018 2019 2018 36.5 — MRA Hub 34 Holding, LLC 95.00% 2.50% + LIBOR 9/1/2022 $ 36.5 $ — 32.8 — THP Student Housing, LLC 97.00% 3.200% 9/1/2024 32.5 — TOTAL LOANS RECEIVABLE WITH RELATED PARTIES $ 69.0 $ —

Concentration Risk (Tables)

Concentration Risk (Tables)	12 Months Ended
	Dec. 31, 2019
Risks and Uncertainties [Abstract]
Schedules of Diversification of Portfolio, by Region and Property Type	The following table represents the diversification of the Account’s portfolio by region and property type as of December 31, 2019 : Diversification by Fair Value (1) West East South Midwest Total Office 13.1 % 18.8 % 5.3 % — % 37.2 % Apartment 10.1 % 7.7 % 7.4 % 1.0 % 26.2 % Retail 6.9 % 3.9 % 7.7 % 0.8 % 19.3 % Industrial 9.0 % 1.6 % 4.7 % 0.5 % 15.8 % Other (2) 0.5 % 0.4 % 0.6 % — % 1.5 % Total 39.6 % 32.4 % 25.7 % 2.3 % 100.0 % (1) Wholly-owned properties are represented at fair value and gross of any debt, while joint venture properties are represented at the net equity value. (2) Represents interests in Storage Portfolio investments, a hotel investment and land. Properties in the “West” region are located in: AK, AZ, CA, CO, HI, ID, MT, NM, NV, OR, UT, WA, WY Properties in the “East” region are located in: CT, DC, DE, KY, MA, MD, ME, NC, NH, NJ, NY, PA, RI, SC, VA, VT, WV Properties in the “South” region are located in: AL, AR, FL, GA, LA, MS, OK, TN, TX Properties in the “Midwest” region are located in: IA, IL, IN, KS, MI, MN, MO, ND, NE, OH, SD, WI

Leases (Tables)

Leases (Tables)	12 Months Ended
	Dec. 31, 2019
Leases [Abstract]
Schedule of Aggregate Minimum Annual Rental Payments, After Adopting 842	Aggregate minimum annual rentals for wholly-owned real estate investments owned by the Account through the non-cancelable lease term, excluding short-term residential leases, are as follows (millions): For the Years Ending December 31, 2020 $ 550.4 2021 505.0 2022 442.1 2023 381.2 2024 316.6 Thereafter 1,078.4 Total $ 3,273.7
Schedule of Right-of-Use Assets and Lease Liabilities Related to Ground Leases	The fair values and key terms of the right-of-use assets and lease liabilities related to the Account's ground leases are as follows (millions): As of December 31, 2019 Assets: Right-of-use assets, at fair value $ 25.7 Liabilities: Ground lease liabilities, at fair value $ 25.7 Key Terms Weighted-average remaining lease term (years) 84.4 Weighted-average discount rate (1) 6.15 % (1) Discount rates are reflective of the rates utilized during the most recent appraisal of the associated real estate investments.
Schedule of Aggregate Minimum Annual Payments for Ground Leases, After Adopting 842	Aggregate future minimum annual payments for ground leases held by the Account are as follows (millions): For the Years Ending December 31, 2020 $ 1.2 2021 1.2 2022 1.2 2023 1.2 2024 1.3 Thereafter 375.9 Total $ 382.0

Assets and Liabilities Measur_2

Assets and Liabilities Measured at Fair Value on a Recurring Basis (Tables)	12 Months Ended
	Dec. 31, 2019
Fair Value Disclosures [Abstract]
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis	The following tables show the major categories of assets and liabilities measured at fair value on a recurring basis as of December 31, 2019 and 2018 , using unadjusted quoted prices in active markets for identical assets (Level 1); significant other observable inputs (Level 2); significant unobservable inputs (Level 3); and Practical Expedient (millions): Description Level 1: Quoted Prices in Active Markets for Identical Assets Level 2: Significant Other Observable Inputs Level 3: Significant Unobservable Inputs Fair Value Using Practical Expedient Total at December 31, 2019 Real estate properties $ — $ — $ 15,835.0 $ — $ 15,835.0 Real estate joint ventures — — 7,204.2 — 7,204.2 Real estate funds — — — 311.8 311.8 Marketable securities: Real estate-related 825.7 — — — 825.7 Government agency notes — 259.6 — — 259.6 United States Treasury securities — 2,589.1 — — 2,589.1 Corporate bonds — 1,268.3 — — 1,268.3 Municipal bonds — 33.2 — — 33.2 Loans receivable (1) — — 1,572.1 — 1,572.1 Total Investments at $ 825.7 $ 4,150.2 $ 24,611.3 $ 311.8 $ 29,899.0 Loans payable $ — $ — $ (2,365.0 ) $ — $ (2,365.0 ) Line of credit $ — $ — $ (250.0 ) $ — $ (250.0 ) (1) Amount shown is reflective of loans receivable and loans receivable with related parties. Description Level 1: Quoted Prices in Active Markets for Identical Assets Level 2: Significant Other Observable Inputs Level 3: Significant Unobservable Inputs Fair Value Using Practical Expedient Total at December 31, 2018 Real estate properties $ — $ — $ 15,531.1 $ — $ 15,531.1 Real estate joint ventures — — 6,356.6 — 6,356.6 Real estate funds — — — 175.9 175.9 Marketable securities: Real estate-related 1,415.1 — — — 1,415.1 Government agency notes — 2,050.7 — — 2,050.7 United States Treasury securities — 2,038.0 — — 2,038.0 Loans receivable — — 913.0 — 913.0 Total Investments at $ 1,415.1 $ 4,088.7 $ 22,800.7 $ 175.9 $ 28,480.4 Loans payable $ — $ — $ (2,608.0 ) $ — $ (2,608.0 )
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation	The following tables show the reconciliation of the beginning and ending balances for assets and liabilities measured at fair value on a recurring basis using significant unobservable inputs (Level 3) during the years ended December 31, 2019 and 2018 (millions): Real Estate Properties Real Estate Joint Ventures Loans Receivable (3) Total Level 3 Investments Line of Credit For the year ended December 31, 2019 Beginning balance January 1, 2019 $ 15,531.1 $ 6,356.6 $ 913.0 $ 22,800.7 $ (2,608.0 ) $ — Total realized and unrealized gains(losses) included in changes in net assets 526.3 (100.3 ) (4.1 ) 421.9 (107.1 ) — Purchases (1) 1,534.9 953.0 764.8 3,252.7 (228.5 ) (250.0 ) Sales (1,757.3 ) — — (1,757.3 ) — — Settlements (2) — (5.1 ) (101.6 ) (106.7 ) 578.6 — Ending balance December 31, 2019 $ 15,835.0 $ 7,204.2 $ 1,572.1 $ 24,611.3 $ (2,365.0 ) $ (250.0 ) Real Estate Properties Real Estate Joint Ventures Loans Receivable Total Level 3 Investments Loans Payable For the year ended December 31, 2018 Beginning balance January 1, 2018 $ 15,742.7 $ 5,860.6 $ 298.8 $ 21,902.1 $ (2,238.3 ) Total realized and unrealized gains included in changes in net assets 315.8 116.3 0.3 432.4 79.4 Purchases (1) 1,151.8 941.5 939.2 3,032.5 (817.9 ) Sales (1,679.2 ) — (257.3 ) (1,936.5 ) — Settlements (2) — (561.8 ) (68.0 ) (629.8 ) 368.8 Ending balance December 31, 2018 $ 15,531.1 $ 6,356.6 $ 913.0 $ 22,800.7 $ (2,608.0 ) (1) Includes purchases, contributions for joint ventures, capital expenditures, lending for loans receivable and assumption of loans payable. (2) Includes operating income for real estate joint ventures net of distributions, principal payments and payoffs of loans receivable, and principal payments and extinguishment of loans payable. (3) Amount shown is reflective of loans receivable and loans receivable with related parties.
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation	The following tables show the reconciliation of the beginning and ending balances for assets and liabilities measured at fair value on a recurring basis using significant unobservable inputs (Level 3) during the years ended December 31, 2019 and 2018 (millions): Real Estate Properties Real Estate Joint Ventures Loans Receivable (3) Total Level 3 Investments Line of Credit For the year ended December 31, 2019 Beginning balance January 1, 2019 $ 15,531.1 $ 6,356.6 $ 913.0 $ 22,800.7 $ (2,608.0 ) $ — Total realized and unrealized gains(losses) included in changes in net assets 526.3 (100.3 ) (4.1 ) 421.9 (107.1 ) — Purchases (1) 1,534.9 953.0 764.8 3,252.7 (228.5 ) (250.0 ) Sales (1,757.3 ) — — (1,757.3 ) — — Settlements (2) — (5.1 ) (101.6 ) (106.7 ) 578.6 — Ending balance December 31, 2019 $ 15,835.0 $ 7,204.2 $ 1,572.1 $ 24,611.3 $ (2,365.0 ) $ (250.0 ) Real Estate Properties Real Estate Joint Ventures Loans Receivable Total Level 3 Investments Loans Payable For the year ended December 31, 2018 Beginning balance January 1, 2018 $ 15,742.7 $ 5,860.6 $ 298.8 $ 21,902.1 $ (2,238.3 ) Total realized and unrealized gains included in changes in net assets 315.8 116.3 0.3 432.4 79.4 Purchases (1) 1,151.8 941.5 939.2 3,032.5 (817.9 ) Sales (1,679.2 ) — (257.3 ) (1,936.5 ) — Settlements (2) — (561.8 ) (68.0 ) (629.8 ) 368.8 Ending balance December 31, 2018 $ 15,531.1 $ 6,356.6 $ 913.0 $ 22,800.7 $ (2,608.0 ) (1) Includes purchases, contributions for joint ventures, capital expenditures, lending for loans receivable and assumption of loans payable. (2) Includes operating income for real estate joint ventures net of distributions, principal payments and payoffs of loans receivable, and principal payments and extinguishment of loans payable. (3) Amount shown is reflective of loans receivable and loans receivable with related parties.
Schedule of Unobservable Inputs Related to Level 3 Fair Value Measurements	The following table shows quantitative information about unobservable inputs related to the Level 3 fair value measurements as of December 31, 2019 . Type Asset Class Valuation Technique(s) Unobservable Inputs Range (Weighted Average) Real Estate Properties and Joint Ventures Office Income Approach—Discounted Cash Flow Discount Rate 5.5%–8.5% (6.6%) Terminal Capitalization Rate 4.0%–7.5% (5.5%) Income Approach—Direct Capitalization Overall Capitalization Rate 3.9%–7.0% (5.0%) Industrial Income Approach—Discounted Cash Flow Discount Rate 5.3% - 9.0% (6.7%) Terminal Capitalization Rate 4.3% - 8.1% (5.5%) Income Approach—Direct Capitalization Overall Capitalization Rate 3.9% - 7.4% (4.9%) Residential Income Approach—Discounted Cash Flow Discount Rate 5.3% - 7.8% (6.4%) Terminal Capitalization Rate 4.3% - 6.8% (5.1%) Income Approach—Direct Capitalization Overall Capitalization Rate 3.8% - 6.0% (4.6%) Retail Income Approach—Discounted Cash Flow Discount Rate 5.3% - 11.7% (6.6%) Terminal Capitalization Rate 4.8% - 9.4% (5.4%) Income Approach—Direct Capitalization Overall Capitalization Rate 3.3% - 11.0% (4.9%) Hotel Income Approach—Discounted Cash Flow Discount Rate 10.0% (10.0%) Terminal Capitalization Rate 7.8% (7.8%) Income Approach—Direct Capitalization Overall Capitalization Rate 7.5% (7.5%) Loans Payable Office and Industrial Discounted Cash Flow Loan-to-Value Ratio 31.6% - 59.5% (46.3%) Equivalency Rate 3.1% - 4.3% (3.4%) Net Present Value Loan-to-Value Ratio 31.6% - 59.5% (46.3%) Weighted Average Cost of Capital Risk Premium Multiple 1.2 - 1.5 (1.3) Residential Discounted Cash Flow Loan-to-Value Ratio 30.2% - 69.0% (47.8%) Equivalency Rate 3.0% - 3.6% (3.3%) Net Present Value Loan-to-Value Ratio 30.2% - 69.0% (47.8%) Weighted Average Cost of Capital Risk Premium Multiple 1.2 - 1.7 (1.3) Retail Discounted Cash Flow Loan-to-Value Ratio 33.3% - 63.3% (41.1%) Equivalency Rate 3.3% - 4.0% (3.5%) Net Present Value Loan-to-Value Ratio 33.3% - 63.3% (41.1%) Weighted Average Cost of Capital Risk Premium Multiple 1.2 - 1.5 (1.3) Loans Receivable, including those with related parties Residential, Hotel, Industrial, Office, Retail and Storage Discounted Cash Flow Loan-to-Value Ratio 31.7% - 81.5% (72.5%) Equivalency Rate 3.2% - 8.4% (6.0%) The following table shows quantitative information about unobservable inputs related to the Level 3 fair value measurements as of December 31, 2018. Type Asset Class Valuation Technique(s) Unobservable Inputs Range (Weighted Average) Real Estate Properties and Joint Ventures Office Income Approach—Discounted Cash Flow Discount Rate 5.5%–8.6% (6.5%) Terminal Capitalization Rate 4.0%–7.5% (5.4%) Income Approach—Direct Capitalization Overall Capitalization Rate 4.0%–7.0% (4.8%) Industrial Income Approach—Discounted Cash Flow Discount Rate 5.3%–8.9% (6.8%) Terminal Capitalization Rate 4.4%–7.3% (5.5%) Income Approach—Direct Capitalization Overall Capitalization Rate 4.0%–7.0% (4.9%) Residential Income Approach—Discounted Cash Flow Discount Rate 5.5%–7.8% (6.5%) Terminal Capitalization Rate 3.8%–6.8% (5.0%) Income Approach—Direct Capitalization Overall Capitalization Rate 3.3%–6.0% (4.5%) Retail Income Approach—Discounted Cash Flow Discount Rate 5.0%–10.7% (6.4%) Terminal Capitalization Rate 4.3%–9.0% (5.3%) Income Approach—Direct Capitalization Overall Capitalization Rate 3.3%–8.5% (4.7%) Loans Payable Office and Industrial Discounted Cash Flow Loan-to-Value Ratio 36.4%–67.8% (47.6%) Equivalency Rate 3.9%–6.2% (4.6%) Net Present Value Loan-to-Value Ratio 36.4%–67.8% (47.6%) Weighted Average Cost of Capital Risk Premium Multiple 1.2–1.4 (1.3) Residential Discounted Cash Flow Loan-to-Value Ratio 31.9%–63.6% (48.1%) Equivalency Rate 3.4%–4.6% (4.1%) Net Present Value Loan-to-Value Ratio 31.9%–63.6% (48.1%) Weighted Average Cost of Capital Risk Premium Multiple 1.1–1.4 (1.2) Retail Discounted Cash Flow Loan-to-Value Ratio 31.9%–55.3% (39.3%) Equivalency Rate 4.3%–5.3% (4.5%) Net Present Value Loan-to-Value Ratio 31.9%–55.3% (39.3%) Weighted Average Cost of Capital Risk Premium Multiple 1.1–1.3 (1.2) Loans Receivable Residential, Industrial, Office, Retail and Storage Discounted Cash Flow Loan-to-Value Ratio 70.8%-79.2% (75.6%) Equivalency Rate 6.0%-8.3% (6.9%)
Fair Value of Net Unrealized Gains Included in Changes in Net Assets Attributable to Investments and Mortgage Loans Payable Using Significant Unobservable Inputs	The amount of total net unrealized gains included in changes in net assets attributable to the change in net unrealized gains relating to Level 3 investments and loans payable using significant unobservable inputs still held as of the reporting date is as follows (millions): Real Estate Properties Real Estate Joint Ventures Loans Receivable Total Level 3 Investments Mortgage Loans Payable For the year ended December 31, 2019 $ 355.2 $ (94.7 ) $ (4.1 ) $ 256.4 $ (96.8 ) For the year ended December 31, 2018 $ 282.6 $ 80.8 $ 0.3 $ 363.7 $ 86.2

Investments in Joint Ventures (

Investments in Joint Ventures (Tables)	12 Months Ended
	Dec. 31, 2019
Equity Method Investments and Joint Ventures [Abstract]
Schedule of Financial Position of the Joint Venture	A condensed summary of the gross financial position and results of operations of the combined joint ventures is shown below (millions): December 31, 2019 2018 Assets Real estate properties, at fair value $ 17,455.8 $ 16,134.1 Other assets 485.9 460.3 Total assets $ 17,941.7 $ 16,594.4 Liabilities & Equity Mortgage notes payable and other obligations, at fair value $ 5,185.3 $ 5,035.3 Other liabilities 256.3 262.5 Total liabilities 5,441.6 5,297.8 Total equity 12,500.1 11,296.6 Total liabilities and equity $ 17,941.7 $ 16,594.4
Schedule of Results of Operations of the Joint Venture	Years ended December 31, 2019 2018 2017 Operating Revenue and Expenses Revenues $ 1,126.5 $ 950.6 $ 869.2 Expenses 604.1 487.1 426.9 Excess of revenues over expenses $ 522.4 $ 463.5 $ 442.3

Investments in Real Estate Fu_2

Investments in Real Estate Funds (Tables)	12 Months Ended
	Dec. 31, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Schedule of Carrying Amount and Maximum Exposure to Loss Relating to VIEs	The carrying amount and maximum exposure to loss relating to VIEs in which the Company holds a significant variable interest but is not the primary beneficiary and which have not been consolidated were as follows at December 31, 2019 . Fund Name Carrying Amount Maximum Exposure to Loss Liquidity Provisions Investment Strategy (in millions) LCS SHIP Venture I, LLC (90.0% Account Interest) $ 216.1 $ 216.1 Redemptions prohibited prior to liquidation. To invest in senior housing properties. Liquidation estimated to begin no earlier than 2025. The Account is permitted to sell or transfer its interest in the fund, subject to consent and approval of the manager. SP V - II, LLC (75.0% Account Interest) $ 23.3 $ 23.3 Redemptions prohibited prior to liquidation. To invest in medical office properties in the U.S. Liquidation estimated to begin no earlier than 2022. The Account is permitted to sell or transfer its interest in the fund, subject to consent and approval of the manager. Taconic New York City GP Fund, LP (60.0% Account Interest) $ 29.8 $ 29.8 Redemptions prohibited prior to liquidation. To invest in real estate and real estate-related assets in the New York City metropolitan statistical area ("MSA"). Liquidation estimated to begin no earlier than 2024. The Account is permitted to sell its interest in the fund, subject to consent and approval of the general partner. Veritas - Trophy VI, LLC (90.0% Account Interest) $ 4.2 $ 4.2 Redemptions prohibited prior to liquidation. To invest in multi-family properties primarily in the San Francisco Bay and Los Angeles MSA. The Account is not permitted to sell or transfer its interest in the fund until August 2022. After this date, the Account can sell or transfer its interest in the fund with the consent and approval of the manager. Fund Name Carrying Amount Maximum Exposure to Loss Liquidity Provisions Investment Strategy (in millions) IDR - Core Property Index Fund, LLC (2.0% Account Interest) $ 25.0 $ 25.0 Redemptions are permitted for a full calendar quarter and upon at least 90 days prior written notice, subject to fund availability. To invest primarily in open-ended funds that fall within the NFI-ODCE Index and are actively managed. The Account is permitted to sell its interest in the fund, subject to consent and approval of the manager. Grubb Southeast Real Estate Fund VI, LLC (67.0% Account Interest) $ 13.4 $ 13.4 Redemptions prohibited prior to liquidation. To acquire office investments across the Southeast. Liquidation estimated to begin no earlier than 2026. The Account is not permitted to sell or transfer its interest in the fund until June 2021. After this date, the Account can sell or transfer its interest in the fund with the consent and approval of the manager. Total $ 311.8 $ 311.8

Loans Receivable (Tables)

Loans Receivable (Tables)	12 Months Ended
	Dec. 31, 2019
Receivables [Abstract]
Schedule of Loans Receivable, Property Types	The following property types represent the underlying real estate collateral for the Account's mezzanine loans (millions): December 31, 2019 December 31, 2018 Fair Value % Fair Value % Office (1) $ 768.0 48.8 % $ 512.1 56.2 % Industrial 199.6 12.7 % 176.4 19.3 % Retail 158.5 10.1 % 101.6 11.1 % Storage 82.0 5.2 % 63.2 6.9 % Apartments (1) 228.8 14.6 % 59.7 6.5 % Hotel 135.2 8.6 % — — % $ 1,572.1 100.0 % $ 913.0 100.0 % (1) Includes loans receivable with related parties.
Schedule of Fair Value and Risk Ratings	The following table presents the fair values of the Account's loan portfolio based on the risk ratings as of December 31, 2019 , listed in order of the strength of the risk rating (from strongest to weakest): Number of Loans Fair Value % AA 1 48.3 3.1 % BBB 7 456.1 29.0 % BB 13 787.4 50.1 % B 3 205.0 13.0 % NR (1) 3 75.3 4.8 % 27 $ 1,572.1 100.0 % (1) "NR" designates loans not assigned an internal credit rating. As of December 31, 2019 , this is comprised of two loans with related parties and one loan to an unaffiliated entity. The loans are collateralized by equity interests in real estate investments.

Loans Payable (Tables)

Loans Payable (Tables)	12 Months Ended
	Dec. 31, 2019
Debt Disclosure [Abstract]
Schedule of Outstanding Mortgage Loans Payable Secured by Properties	At December 31, 2019 and 2018, the Account had outstanding loans payable secured by the following properties (millions): Property Interest Rate and Payment Frequency (2) Principal Amounts Outstanding as of December 31, Maturity 2019 2018 Mass Court 2.88% paid monthly $ — $ 90.2 September 1, 2019 Red Canyon at Palomino Park (4) 5.34% paid monthly 27.1 27.1 August 1, 2020 Green River at Palomino Park (4) 5.34% paid monthly 33.2 33.2 August 1, 2020 Blue Ridge at Palomino Park (4) 5.34% paid monthly 33.4 33.4 August 1, 2020 Ashford Meadows Apartments 5.17% paid monthly 44.6 44.6 August 1, 2020 The Knoll (1) 3.98% paid monthly 16.4 16.9 December 5, 2020 Ascent at Windward 3.51% paid monthly 34.6 34.6 January 1, 2022 The Palatine (1) 4.25% paid monthly 75.9 77.4 January 10, 2022 The Forum at Carlsbad (1) 4.25% paid monthly 85.7 87.3 March 1, 2022 Fusion 1560 3.42% paid monthly 37.4 37.4 June 10, 2022 San Diego Office Portfolio 3.62% paid monthly 48.2 — August 15, 2022 The Colorado (1) 3.69% paid monthly 88.1 89.9 November 1, 2022 The Legacy at Westwood (1) 3.69% paid monthly 44.9 45.8 November 1, 2022 Regents Court (1) 3.69% paid monthly 38.1 38.8 November 1, 2022 Fourth & Madison 3.75% paid monthly — 198.2 June 1, 2023 Fourth & Madison 4.17% paid monthly — 90.0 June 1, 2023 1001 Pennsylvania Avenue (1) 3.70% paid monthly 320.7 327.0 June 1, 2023 Biltmore at Midtown 3.94% paid monthly 36.4 36.4 July 5, 2023 Cherry Knoll 3.78% paid monthly 35.3 35.3 July 5, 2023 Lofts at SoDo 3.94% paid monthly 35.1 35.1 July 5, 2023 1401 H Street, NW 3.65% paid monthly 115.0 115.0 November 5, 2024 The District at La Frontera (1) 3.84% paid monthly 39.3 — December 1, 2024 The District at La Frontera (1) 4.96% paid monthly 4.4 — December 1, 2024 Circa Green Lake 3.71% paid monthly 52.0 52.0 March 5, 2025 Union - South Lake Union 3.66% paid monthly 57.0 57.0 March 5, 2025 Holly Street Village 3.65% paid monthly 81.0 81.0 May 1, 2025 Township Apartments 3.65% paid monthly — 49.0 May 1, 2025 Henley at Kingstowne 3.60% paid monthly 71.0 — May 1, 2025 32 South State Street 4.48% paid monthly 24.0 24.0 June 6, 2025 Vista Station Office Portfolio (1) 4.00% paid monthly 20.5 — July 1, 2025 780 Third Avenue 3.55% paid monthly 150.0 150.0 August 1, 2025 780 Third Avenue 3.55% paid monthly 20.0 20.0 August 1, 2025 Vista Station Office Portfolio (1) 4.20% paid monthly 44.7 — November 1, 2025 701 Brickell Avenue 3.66% paid monthly 184.0 184.0 April 1, 2026 55 Second Street 3.74% paid monthly — 137.5 October 1, 2026 1900 K Street, NW 3.93% paid monthly 163.0 163.0 April 1, 2028 99 High Street 3.90% paid monthly 277.0 277.0 March 1, 2030 Total Principal Outstanding $ 2,338.0 $ 2,688.1 Fair Value Adjustment (3) 27.0 (80.1 ) Total Loans Payable $ 2,365.0 $ 2,608.0 (1) The mortgage is adjusted monthly for principal payments. (2) Interest rates are fixed. Some mortgages held by the Account are structured to begin principal and interest payments after an initial interest only period. (3) The fair value adjustment consists of the difference (positive or negative) between the principal amount of the outstanding debt and the fair value of the outstanding debt. See Note 1—Organization and Significant Accounting Policies. (4) Represents mortgage loans on these individual properties which are held within the Palomino Park portfolio.
Schedule of Maturities of Long-term Debt	Principal payment schedule on loans payable as of December 31, 2019 was as follows (millions): Amount 2020 $ 170.9 2021 19.7 2022 455.5 2023 418.2 2024 165.4 Thereafter 1,108.3 Total maturities $ 2,338.0

Financial Highlights (Tables)

Financial Highlights (Tables)	12 Months Ended
	Dec. 31, 2019
Condensed Financial Information Disclosure [Abstract]
Schedule of Condensed Financial Information for an Accumulation Unit of the Account	Selected condensed financial information for an Accumulation Unit of the Account is presented below. Per Accumulation Unit data is calculated on average units outstanding. Years ended December 31, 2019 2018 2017 2016 2015 Per Accumulation Unit Data: Rental income $ 18.165 $ 17.757 $ 17.132 $ 16.433 $ 15.538 Real estate property level expenses and taxes 8.734 8.548 7.722 7.534 7.319 Real estate income, net 9.431 9.209 9.410 8.899 8.219 Other income 6.752 6.162 4.762 3.594 3.342 Total income 16.183 15.371 14.172 12.493 11.561 Expense charges (1) 3.439 3.161 3.318 3.290 3.092 Investment income, net 12.744 12.210 10.854 9.203 8.469 Net realized and unrealized gain on investments and loans payable 10.262 6.877 5.839 9.660 18.911 Net increase in Accumulation Unit Value 23.006 19.087 16.693 18.863 27.380 Accumulation Unit Value: Beginning of period 417.416 398.329 381.636 362.773 335.393 End of period $ 440.422 $ 417.416 $ 398.329 $ 381.636 $ 362.773 Total return 5.51 % 4.79 % 4.37 % 5.20 % 8.16 % Ratios to Average net Assets: Expenses (1) 0.78 % 0.76 % 0.83 % 0.86 % 0.86 % Investment income, net 2.90 % 2.95 % 2.72 % 2.41 % 2.37 % Portfolio turnover rate: Real estate properties (2) 7.8 % 11.8 % 2.7 % 1.3 % 5.7 % Marketable securities (3) 28.7 % 5.1 % 5.7 % 3.5 % 10.0 % Accumulation Units outstanding at end of period (millions): 60.8 60.7 61.3 62.4 60.4 Net assets end of period (millions) $ 27,307.9 $ 25,842.6 $ 24,942.6 $ 24,304.7 $ 22,360.0 (1) Expense charges per Accumulation Unit and the Ratio of Expenses to average net assets reflect the year to date Account level expenses and exclude real estate property level expenses which are included in real estate income, net. (2) Real estate investment portfolio turnover rate is calculated by dividing the lesser of purchases or sales of real estate property investments (including contributions to, or return of capital distributions received from, existing joint venture and Funds investments) by the average value of the portfolio of real estate investments held during the period. (3) Marketable securities portfolio turnover rate is calculated by dividing the lesser of purchases or sales of securities, excluding securities having maturity dates at acquisition of one year or less, by the average value of the portfolio securities held during the period.

Accumulation Units (Tables)

Accumulation Units (Tables)	12 Months Ended
	Dec. 31, 2019
Accumulated Units Disclosure [Abstract]
Schedule of Changes in the Number of Accumulation Units Outstanding	Changes in the number of Accumulation Units outstanding were as follows (millions): Years ended December 31, 2019 2018 2017 Outstanding: Beginning of period 60.7 61.3 62.4 Credited for premiums 6.2 6.5 6.6 Annuity, other periodic payments, withdrawals and death benefits (6.1 ) (7.1 ) (7.7 ) End of period 60.8 60.7 61.3

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2019
Commitments and Contingencies Disclosure [Abstract]
Schedule of Callable Commitments	As of December 31, 2019 and 2018 , the Account had the following immediately callable commitments to purchase additional interests in its real estate funds or provide additional funding through its loan receivable investments: Commitment Expiration December 31, 2019 December 31, 2018 Real Estate Funds (1) Taconic New York City GP Fund 11/2020 $ 11.4 $ 26.0 LCS SHIP Venture I, LLC 12/2020 28.1 75.0 Veritas Trophy VI, LLC (2) 02/2020 35.8 — SP V - II, LLC 09/2022 74.9 — Grubb Southeast Real Estate Fund VI, LLC 06/2021 86.6 — JCR Capital - REA Preferred Equity Parallel Fund 12/2022 100.0 — Townsend Strategic Ventures LP 03/2021 250.0 — 586.8 101.0 Loans Receivable (3) 311 South Wacker Mezzanine 06/2020 7.6 11.9 Rosemont Towson Mezzanine 09/2022 1.2 2.3 1330 Broadway Mezzanine 09/2022 14.0 14.8 SCG Oakland Portfolio Mezzanine 03/2021 7.0 — BREP VIII Industrial Mezzanine 03/2026 14.1 — San Diego Office Portfolio Senior Loan 08/2022 10.0 — San Diego Office Portfolio Mezzanine 08/2022 3.3 — MRA Hub 34 Holding, LLC 09/2022 1.5 — Liberty Park Mezzanine 11/2023 5.0 — Colony New England Hotel Portfolio Senior Loan 11/2022 14.1 — Colony New England Hotel Portfolio Mezzanine 11/2022 4.7 — Exo Apartments Senior Loan 06/2020 7.1 — Exo Apartments Mezzanine 06/2020 2.4 — 92.0 29.0 TOTAL COMMITMENTS $ 678.8 $ 130.0 (1) Additional capital can be called during the commitment period at any time. The commitment period can only be extended by the manager with the consent of the Account. The commitment expiration date is reflective of the most recent signed agreement between the Account and the fund manager, including any side letter agreements. (2) The fund manager is granted 18 months from the initial contribution date, August 2019, to make its first capital call. If none have occurred, the Account's commitment will be reduced by $15.0 million . If a capital call occurs during the initial 18 month window, the commitment period will be modified to three years from the first capital call date. (3) Additional advances from the Account can be requested during the commitment period at any time. The commitment expiration date is reflective of the most recent signed agreement between the Account and the borrower, including any side letter agreements. Certain loans contain extension clauses on the term of the loan that do not require the Account's prior consent. If elected, the Account's commitment may be extended through the extension term.

Subsequent Events (Tables)

Subsequent Events (Tables)	12 Months Ended
	Dec. 31, 2019
Subsequent Events [Abstract]
Schedule of Subsequent Events	Real Estate Properties and Joint Ventures Purchases Property Name Transaction Date Ownership Percentage Sector Location Net Purchase Price (1) Sole at City Center 01/15/2020 100.00% Apartments West Palm Beach, FL $ 103.6 Park Creek Apartments 02/10/2020 100.00% Apartments Fort Worth, TX 41.7 Warwick Shopping Center (2) 02/19/2020 100.00% Retail Warwick, RI 11.1 Overlook at King of Prussia (2) 02/19/2020 100.00% Retail King of Prussia, PA 55.1 Shoppes at Lake Mary (2) 02/19/2020 100.00% Retail Lake Mary, FL 21.0 Winslow Bay Commons (2) 02/19/2020 100.00% Retail Mooresville, NC 50.9 Bellevue Place (2) 02/19/2020 100.00% Retail Nashville, TN 7.8 Eisenhower Crossing (2) 02/19/2020 100.00% Retail Macon, GA 10.1 Pavilion at Turkey Creek (2) 02/19/2020 100.00% Retail Knoxville, TN 49.9 Town and Country (2) 02/19/2020 100.00% Retail Knoxville, TN 30.1 Creeks at Virginia Center (2) 02/19/2020 100.00% Retail Glen Allen, VA 41.7 Alexander Place (2) 02/19/2020 100.00% Retail Raleigh, NC 39.9 Market Square (2) 02/19/2020 100.00% Retail Ft. Myers, FL 20.4 Cypress Trace (2) 02/19/2020 100.00% Retail Ft. Myers, FL 39.7 Columbiana Station (2) 02/19/2020 100.00% Retail Columbia, SC 43.8 Village Crossing (2) 02/19/2020 100.00% Retail Skokie, IL 160.7 Birkdale Village (2) 02/19/2020 100.00% Retail Huntersville, NC 128.9 Birkdale Village Apartments (2) 02/19/2020 100.00% Apartments Huntersville, NC 70.8 River Ridge (2) 02/19/2020 100.00% Retail Birmingham, AL 28.0 Woodstock Square (2) 02/19/2020 100.00% Retail Woodstock, GA 33.7 Newnan Pavilion (2) 02/19/2020 100.00% Retail Newnan, GA 39.7 Marketplace at Mill Creek (2) 02/19/2020 100.00% Retail Buford, GA 71.5 Heritage Pavilion (2) 02/19/2020 100.00% Retail Smyrna, GA 41.6 Fayette Pavilion (2) 02/19/2020 100.00% Retail Fayetteville, GA 88.4 Pacific City (3) 03/09/2020 100.00% Retail Huntington Beach, CA 153.9 (1) The net purchase price represents the purchase price and closing costs. (2) On February 19, 2020, the Account purchased the 15% ownership interest of SITE Centers Corp in DDRTC Core Retail Fund, LLC, a joint venture between the Account and SITE Centers Corp. All properties and associated debt formerly held within DDRTC Core Retail Fund, LLC are now wholly-owned by the Account. (3) On March 9, 2020, the Account purchased the 30% ownership interest of DJM Capital in PC Borrower, LLC, a joint venture between the Account and DJM Capital. The retail property and associated debt formerly held within PC Borrower, LLC is now wholly-owned by the Account. Sales Property Name Transaction Date Ownership Percentage Sector Location Net Sales Price (1) Realized Gain(Loss) on Sale (2) The Woodley 01/08/2020 100.00% Apartments Washington, D.C. $ 176.7 $ (25.2 ) Beltway North Commerce Center 01/14/2020 100.00% Industrial Houston, TX 29.8 4.3 250 North 10th Street 01/15/2020 100.00% Apartments Brooklyn, NY 137.1 (37.6 ) DDRTC Core Retail Fund, LLC (3) 02/19/2020 85.00% Retail Various, U.S.A. 932.8 (422.2 ) PC Borrower, LLC (4) 03/09/2020 70.00% Retail Huntington Beach, CA 107.7 (31.3 ) (1) The net sales price represents the sales price, less selling expenses. (2) Majority of the realized gain(loss) has been previously recognized as unrealized gains(losses) in the Account's Consolidated Statements of Operations. (3) On February 19, 2020, the Account purchased the 15% ownership interest of SITE Centers Corp in DDRTC Core Retail Fund, LLC, a joint venture between the Account and SITE Centers Corp. All properties and associated debt formerly held within DDRTC Core Retail Fund, LLC are now wholly-owned by the Account. (4) On March 9, 2020, the Account purchased the 30% ownership interest of DJM Capital in PC Borrower, LLC, a joint venture between the Account and DJM Capital. The retail property and associated debt formerly held within PC Borrower, LLC is now wholly-owned by the Account. Loans Receivable Originations and purchases Investment Name Transaction Date Interest Rate Sector Maturity Date Location Amount Sol Y Luna 01/07/2020 6.55% Apartments 01/06/2030 Tucson, AZ $ 53.0 Payoffs and sales Investment Name Transaction Date Interest Rate Sector Maturity Date Location Amount Crest at Las Colinas Station Mezzanine 01/30/2020 5.11% + LIBOR Apartments 05/10/2021 Irving, TX $ 20.0 DJM Capital Partners Mezzanine 03/09/2020 5.00% Retail 03/02/2020 Huntington Beach, CA 6.3 Financings New financings and assumptions of debt Property Name Transaction Date Ownership Percentage Interest Rate Sector Maturity Date Location Amount Overlook at King of Prussia (1) 02/19/2020 100.00% 3.82% Retail 09/11/2027 King of Prussia, PA $ 40.8 Winslow Bay Commons (1) 02/19/2020 100.00% 3.82% Retail 09/11/2027 Mooresville, NC 25.8 Birkdale Village (1) 02/19/2020 100.00% 4.30% Retail 04/01/2024 Huntersville, NC 78.4 Marketplace at Mill Creek (1) 02/19/2020 100.00% 3.82% Retail 09/11/2027 Buford, GA 39.6 Pacific City (2) 03/09/2020 100.00% 2.00% + LIBOR Retail 10/01/2023 Huntington Beach, CA 105.0 Payoffs and assignments of debt Property Name Transaction Date Ownership Percentage Interest Rate Sector Maturity Date Location Amount DDRTC Core Retail Fund, LLC (1) 02/19/2020 85.00% Various Retail Various Various, U.S.A. $ 156.8 PC Borrower, LLC (2) 03/09/2020 70.00% 2.00% + LIBOR Retail 10/01/2023 Huntington Beach, CA 73.5 (1) On February 19, 2020, the Account purchased the 15% ownership interest of SITE Centers Corp in DDRTC Core Retail Fund, LLC, a joint venture between the Account and SITE Centers Corp. All properties and associated debt formerly held within DDRTC Core Retail Fund, LLC are now wholly-owned by the Account. (2) On March 9, 2020, the Account purchased the 30% ownership interest of DJM Capital in PC Borrower, LLC, a joint venture between the Account and DJM Capital. The retail property and associated debt formerly held within PC Borrower, LLC is now wholly-owned by the Account.

Organization and Significant _3

Organization and Significant Accounting Policies (Details)	12 Months Ended
	Dec. 31, 2019
Principal Transaction Revenue [Line Items]
Independent appraisal firm, property rotation, period (at least)	3 years
Description of valuation change of real estate related assets	Also, the independent fiduciary can require additional appraisals if factors or events have occurred that could materially change a property’s value (including those identified above) and such change is not reflected in the quarterly valuation review, or otherwise to ensure that the Account is valued appropriately. The independent fiduciary must also approve any valuation change of real estate-related assets where a property’s value changed by more than 6% from the most recent independent annual appraisal, or if the value of the Account would change by more than 4% within any calendar quarter or more than 2% since the prior calendar month. When a real estate property is subject to a mortgage, the property is valued independently of the mortgage and the property and mortgage fair values are reported separately (see Valuation of Mortgage Loans Payable). The independent fiduciary reviews and approves all mortgage valuation adjustments before such adjustments are recorded by the Account. The Account continues to use the revised value for each real estate property and mortgage loan payable to calculate the Account’s daily net asset value until the next valuation review or appraisal.
Threshold percentage, property value change compared to most recent independent annual appraisal (more than)	6.00%
Threshold percentage, property value change within any calendar quarter (more than)	4.00%
Threshold percentage, property value change compared to prior calendar month (more than)	2.00%
Maximum percentage of average net assets for all account level expenses, percent (not to exceed)	2.50%
Minimum
Principal Transaction Revenue [Line Items]
Investment advisory fees, paid or received, period	1 day
Maximum
Principal Transaction Revenue [Line Items]
Investment advisory fees, paid or received, period	2 days

Related Party Transactions (Det

Related Party Transactions (Details)	12 Months Ended
	Dec. 31, 2019
Related Party Transactions [Abstract]
Distribution agreement, termination period	60 days
Percentage of trigger point on outstanding accumulation units, percent	45.00%

Related Party Transactions - Sc

Related Party Transactions - Schedule of key terms of the loans (Details) - Loans Receivable - Related Party - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Related Party Transaction [Line Items]
TOTAL LOANS RECEIVABLE WITH RELATED PARTIES	$ 69	$ 0
MRA Hub 34 Holding, LLC
Related Party Transaction [Line Items]
Principal	$ 36.5	0
Equity Ownership Interest	95.00%
TOTAL LOANS RECEIVABLE WITH RELATED PARTIES	$ 36.5	0
MRA Hub 34 Holding, LLC | LIBOR
Related Party Transaction [Line Items]
Interest Rate, Variable	2.50%
THP Student Housing, LLC
Related Party Transaction [Line Items]
Principal	$ 32.8	0
Equity Ownership Interest	97.00%
Interest Rate	3.20%
TOTAL LOANS RECEIVABLE WITH RELATED PARTIES	$ 32.5	$ 0

Concentration Risk (Details)

Concentration Risk (Details)	12 Months Ended
	Dec. 31, 2019
Risks and Uncertainties [Abstract]
Maximum percentage of annual contract rent of rental income	3.00%

Concentration Risk - Schedule o

Concentration Risk - Schedule of diversification of the Account's portfolio by region and property type (Details)	12 Months Ended
	Dec. 31, 2019
Concentration Risk [Line Items]
Diversification by fair value	100.00%
Office
Concentration Risk [Line Items]
Diversification by fair value	37.20%
Apartment
Concentration Risk [Line Items]
Diversification by fair value	26.20%
Retail
Concentration Risk [Line Items]
Diversification by fair value	19.30%
Industrial
Concentration Risk [Line Items]
Diversification by fair value	15.80%
Other
Concentration Risk [Line Items]
Diversification by fair value	1.50%
West
Concentration Risk [Line Items]
Diversification by fair value	39.60%
West | Office
Concentration Risk [Line Items]
Diversification by fair value	13.10%
West | Apartment
Concentration Risk [Line Items]
Diversification by fair value	10.10%
West | Retail
Concentration Risk [Line Items]
Diversification by fair value	6.90%
West | Industrial
Concentration Risk [Line Items]
Diversification by fair value	9.00%
West | Other
Concentration Risk [Line Items]
Diversification by fair value	0.50%
East
Concentration Risk [Line Items]
Diversification by fair value	32.40%
East | Office
Concentration Risk [Line Items]
Diversification by fair value	18.80%
East | Apartment
Concentration Risk [Line Items]
Diversification by fair value	7.70%
East | Retail
Concentration Risk [Line Items]
Diversification by fair value	3.90%
East | Industrial
Concentration Risk [Line Items]
Diversification by fair value	1.60%
East | Other
Concentration Risk [Line Items]
Diversification by fair value	0.40%
South
Concentration Risk [Line Items]
Diversification by fair value	25.70%
South | Office
Concentration Risk [Line Items]
Diversification by fair value	5.30%
South | Apartment
Concentration Risk [Line Items]
Diversification by fair value	7.40%
South | Retail
Concentration Risk [Line Items]
Diversification by fair value	7.70%
South | Industrial
Concentration Risk [Line Items]
Diversification by fair value	4.70%
South | Other
Concentration Risk [Line Items]
Diversification by fair value	0.60%
Midwest
Concentration Risk [Line Items]
Diversification by fair value	2.30%
Midwest | Office
Concentration Risk [Line Items]
Diversification by fair value	0.00%
Midwest | Apartment
Concentration Risk [Line Items]
Diversification by fair value	1.00%
Midwest | Retail
Concentration Risk [Line Items]
Diversification by fair value	0.80%
Midwest | Industrial
Concentration Risk [Line Items]
Diversification by fair value	0.50%
Midwest | Other
Concentration Risk [Line Items]
Diversification by fair value	0.00%

Leases - Schedule of aggregate

Leases - Schedule of aggregate minimum annual rental payments (Details) $ in Millions	Dec. 31, 2019USD ($)
Operating Lease, Annual Payments, After Adopting 842
2020	$ 550.4
2021	505
2022	442.1
2023	381.2
2024	316.6
Thereafter	1,078.4
Total	$ 3,273.7

Leases - Schedule of right-of-u

Leases - Schedule of right-of-use assets and lease liabilities related to ground leases (Details) - Ground $ in Millions	Dec. 31, 2019USD ($)
Assets:
Right-of-use assets, at fair value	$ 25.7
Liabilities:
Ground lease liabilities, at fair value	$ 25.7
Key Terms
Weighted-average remaining lease term (years)	84 years 4 months 24 days
Weighted-average discount rate	6.15%

Leases (Details)

Leases (Details) $ in Millions	12 Months Ended
	Dec. 31, 2019USD ($)
Ground
Lessee, Lease, Description [Line Items]
Operating lease cost, related to ground leases	$ 1.3

Leases - Schedule of future min

Leases - Schedule of future minimum annual payments for ground leases (Details) - Ground $ in Millions	Dec. 31, 2019USD ($)
Operating Lease, After Adopting 842
2020	$ 1.2
2021	1.2
2022	1.2
2023	1.2
2024	1.3
Thereafter	375.9
Total	$ 382

Assets and Liabilities Measur_3

Assets and Liabilities Measured at Fair Value on a Recurring Basis - Schedule of fair value assets and liabilities measured on recurring basis (Details) - USD ($) $ in Millions		Dec. 31, 2019	Dec. 31, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Real estate properties		$ 15,835	$ 15,531.1
Marketable securities:
Real estate-related	[1]	825.7	1,415.1
Marketable securities excluding real estate		4,150.2	4,088.7
Total investments (cost: $25,697.4 and $24,169.8)		29,899	28,480.4
Loans payable		(2,365)	(2,608)
Line of credit		(250)	0
Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Real estate properties		15,835	15,531.1
Real estate joint ventures		7,204.2	6,356.6
Real estate funds		311.8	175.9
Marketable securities:
Real estate-related		825.7	1,415.1
Loans receivable		1,572.1	913
Total investments (cost: $25,697.4 and $24,169.8)		29,899	28,480.4
Loans payable		(2,365)	(2,608)
Line of credit		(250)
Recurring | Government agency notes
Marketable securities:
Marketable securities excluding real estate		259.6	2,050.7
Recurring | United States Treasury securities
Marketable securities:
Marketable securities excluding real estate		2,589.1	2,038
Recurring | Corporate bonds
Marketable securities:
Marketable securities excluding real estate		1,268.3
Recurring | Municipal bonds
Marketable securities:
Marketable securities excluding real estate		33.2
Recurring | Level 1: Quoted Prices in Active Markets for Identical Assets
Marketable securities:
Real estate-related		825.7	1,415.1
Total investments (cost: $25,697.4 and $24,169.8)		825.7	1,415.1
Recurring | Level 2: Significant Other Observable Inputs
Marketable securities:
Total investments (cost: $25,697.4 and $24,169.8)		4,150.2	4,088.7
Recurring | Level 2: Significant Other Observable Inputs | Government agency notes
Marketable securities:
Marketable securities excluding real estate		259.6	2,050.7
Recurring | Level 2: Significant Other Observable Inputs | United States Treasury securities
Marketable securities:
Marketable securities excluding real estate		2,589.1	2,038
Recurring | Level 3: Significant Unobservable Inputs
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Real estate properties		15,835	15,531.1
Real estate joint ventures		7,204.2	6,356.6
Marketable securities:
Loans receivable		1,572.1	913
Total investments (cost: $25,697.4 and $24,169.8)		24,611.3	22,800.7
Loans payable		(2,365)	$ (2,608)
Line of credit		$ (250)
[1]	Includes securities loaned of $25.2 million at December 31, 2019 and $67.4 million at December 31, 2018.

Assets and Liabilities Measur_4

Assets and Liabilities Measured at Fair Value on a Recurring Basis - Schedule of fair value assets and liabilities measured on recurring basis using unobservable inputs (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Total realized and unrealized gains(losses) included in changes in net assets	$ 256.4	$ 363.7
Loans Payable
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	(2,608)	(2,238.3)
Total realized and unrealized gains(losses) included in changes in net assets	(107.1)	79.4
Purchases	(228.5)	(817.9)
Settlements	578.6	368.8
Ending balance	(2,365)	(2,608)
Line of Credit
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	0
Purchases	(250)
Ending balance	(250)	0
Real Estate Properties
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	15,531.1	15,742.7
Total realized and unrealized gains(losses) included in changes in net assets	526.3	315.8
Purchases	1,534.9	1,151.8
Sales	(1,757.3)	(1,679.2)
Ending balance	15,835	15,531.1
Real Estate Joint Ventures
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	6,356.6	5,860.6
Total realized and unrealized gains(losses) included in changes in net assets	(100.3)	116.3
Purchases	953	941.5
Settlements	(5.1)	(561.8)
Ending balance	7,204.2	6,356.6
Loans Receivable
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	913	298.8
Total realized and unrealized gains(losses) included in changes in net assets	(4.1)	0.3
Purchases	764.8	939.2
Sales		(257.3)
Settlements	(101.6)	(68)
Ending balance	1,572.1	913
Total Level 3 Investments
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	22,800.7	21,902.1
Total realized and unrealized gains(losses) included in changes in net assets	421.9	432.4
Purchases	3,252.7	3,032.5
Sales	(1,757.3)	(1,936.5)
Settlements	(106.7)	(629.8)
Ending balance	$ 24,611.3	$ 22,800.7

Assets and Liabilities Measur_5

Assets and Liabilities Measured at Fair Value on a Recurring Basis - Schedule of unobservable inputs related to Level 3 fair value measurements (Details) - Fair Value, Inputs, Level 3	Dec. 31, 2019	Dec. 31, 2018
Real Estate Properties and Joint Ventures | Discount Rate | Office | Discounted Cash Flow | Minimum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Real Estate Properties and Joint Ventures	0.055	0.055
Real Estate Properties and Joint Ventures | Discount Rate | Office | Discounted Cash Flow | Maximum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Real Estate Properties and Joint Ventures	0.085	0.086
Real Estate Properties and Joint Ventures | Discount Rate | Office | Discounted Cash Flow | Weighted Average
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Real Estate Properties and Joint Ventures	0.066	0.065
Real Estate Properties and Joint Ventures | Discount Rate | Industrial | Discounted Cash Flow | Minimum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Real Estate Properties and Joint Ventures	0.053	0.053
Real Estate Properties and Joint Ventures | Discount Rate | Industrial | Discounted Cash Flow | Maximum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Real Estate Properties and Joint Ventures	0.090	0.089
Real Estate Properties and Joint Ventures | Discount Rate | Industrial | Discounted Cash Flow | Weighted Average
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Real Estate Properties and Joint Ventures	0.067	0.068
Real Estate Properties and Joint Ventures | Discount Rate | Residential | Discounted Cash Flow | Minimum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Real Estate Properties and Joint Ventures	0.053	0.055
Real Estate Properties and Joint Ventures | Discount Rate | Residential | Discounted Cash Flow | Maximum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Real Estate Properties and Joint Ventures	0.078	0.078
Real Estate Properties and Joint Ventures | Discount Rate | Residential | Discounted Cash Flow | Weighted Average
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Real Estate Properties and Joint Ventures	0.064	0.065
Real Estate Properties and Joint Ventures | Discount Rate | Retail | Discounted Cash Flow | Minimum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Real Estate Properties and Joint Ventures	0.053	0.050
Real Estate Properties and Joint Ventures | Discount Rate | Retail | Discounted Cash Flow | Maximum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Real Estate Properties and Joint Ventures	0.117	0.107
Real Estate Properties and Joint Ventures | Discount Rate | Retail | Discounted Cash Flow | Weighted Average
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Real Estate Properties and Joint Ventures	0.066	0.064
Real Estate Properties and Joint Ventures | Discount Rate | Hotel | Discounted Cash Flow
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Real Estate Properties and Joint Ventures	0.100
Real Estate Properties and Joint Ventures | Discount Rate | Hotel | Discounted Cash Flow | Weighted Average
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Real Estate Properties and Joint Ventures	0.100
Real Estate Properties and Joint Ventures | Capitalization Rate | Office | Discounted Cash Flow | Minimum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Real Estate Properties and Joint Ventures	0.040	0.040
Real Estate Properties and Joint Ventures | Capitalization Rate | Office | Discounted Cash Flow | Maximum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Real Estate Properties and Joint Ventures	0.075	0.075
Real Estate Properties and Joint Ventures | Capitalization Rate | Office | Discounted Cash Flow | Weighted Average
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Real Estate Properties and Joint Ventures	0.055	0.054
Real Estate Properties and Joint Ventures | Capitalization Rate | Office | Income Approach—Direct Capitalization | Minimum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Real Estate Properties and Joint Ventures	0.039	0.040
Real Estate Properties and Joint Ventures | Capitalization Rate | Office | Income Approach—Direct Capitalization | Maximum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Real Estate Properties and Joint Ventures	0.070	0.070
Real Estate Properties and Joint Ventures | Capitalization Rate | Office | Income Approach—Direct Capitalization | Weighted Average
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Real Estate Properties and Joint Ventures	0.050	0.048
Real Estate Properties and Joint Ventures | Capitalization Rate | Industrial | Discounted Cash Flow | Minimum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Real Estate Properties and Joint Ventures	0.043	0.045
Real Estate Properties and Joint Ventures | Capitalization Rate | Industrial | Discounted Cash Flow | Maximum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Real Estate Properties and Joint Ventures	0.081	0.073
Real Estate Properties and Joint Ventures | Capitalization Rate | Industrial | Discounted Cash Flow | Weighted Average
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Real Estate Properties and Joint Ventures	0.055	0.055
Real Estate Properties and Joint Ventures | Capitalization Rate | Industrial | Income Approach—Direct Capitalization | Minimum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Real Estate Properties and Joint Ventures	0.039	0.040
Real Estate Properties and Joint Ventures | Capitalization Rate | Industrial | Income Approach—Direct Capitalization | Maximum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Real Estate Properties and Joint Ventures	0.074	0.070
Real Estate Properties and Joint Ventures | Capitalization Rate | Industrial | Income Approach—Direct Capitalization | Weighted Average
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Real Estate Properties and Joint Ventures	0.049	0.049
Real Estate Properties and Joint Ventures | Capitalization Rate | Residential | Discounted Cash Flow | Minimum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Real Estate Properties and Joint Ventures	0.043	0.038
Real Estate Properties and Joint Ventures | Capitalization Rate | Residential | Discounted Cash Flow | Maximum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Real Estate Properties and Joint Ventures	0.068	0.068
Real Estate Properties and Joint Ventures | Capitalization Rate | Residential | Discounted Cash Flow | Weighted Average
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Real Estate Properties and Joint Ventures	0.051	0.050
Real Estate Properties and Joint Ventures | Capitalization Rate | Residential | Income Approach—Direct Capitalization | Minimum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Real Estate Properties and Joint Ventures	0.038	0.033
Real Estate Properties and Joint Ventures | Capitalization Rate | Residential | Income Approach—Direct Capitalization | Maximum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Real Estate Properties and Joint Ventures	0.060	0.060
Real Estate Properties and Joint Ventures | Capitalization Rate | Residential | Income Approach—Direct Capitalization | Weighted Average
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Real Estate Properties and Joint Ventures	0.046	0.045
Real Estate Properties and Joint Ventures | Capitalization Rate | Retail | Discounted Cash Flow | Minimum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Real Estate Properties and Joint Ventures	0.048	0.043
Real Estate Properties and Joint Ventures | Capitalization Rate | Retail | Discounted Cash Flow | Maximum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Real Estate Properties and Joint Ventures	0.094	0.090
Real Estate Properties and Joint Ventures | Capitalization Rate | Retail | Discounted Cash Flow | Weighted Average
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Real Estate Properties and Joint Ventures	0.054	0.053
Real Estate Properties and Joint Ventures | Capitalization Rate | Retail | Income Approach—Direct Capitalization | Minimum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Real Estate Properties and Joint Ventures	0.033	0.033
Real Estate Properties and Joint Ventures | Capitalization Rate | Retail | Income Approach—Direct Capitalization | Maximum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Real Estate Properties and Joint Ventures	0.110	0.085
Real Estate Properties and Joint Ventures | Capitalization Rate | Retail | Income Approach—Direct Capitalization | Weighted Average
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Real Estate Properties and Joint Ventures	0.049	0.047
Real Estate Properties and Joint Ventures | Capitalization Rate | Hotel | Discounted Cash Flow
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Real Estate Properties and Joint Ventures	0.078
Real Estate Properties and Joint Ventures | Capitalization Rate | Hotel | Discounted Cash Flow | Weighted Average
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Real Estate Properties and Joint Ventures	0.078
Real Estate Properties and Joint Ventures | Capitalization Rate | Hotel | Income Approach—Direct Capitalization
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Real Estate Properties and Joint Ventures	0.075
Real Estate Properties and Joint Ventures | Capitalization Rate | Hotel | Income Approach—Direct Capitalization | Weighted Average
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Real Estate Properties and Joint Ventures	0.075
Loans Payable | Loan-to-Value Ratio | Residential | Discounted Cash Flow | Minimum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans Payable	0.302	0.319
Loans Payable | Loan-to-Value Ratio | Residential | Discounted Cash Flow | Maximum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans Payable	0.690	0.636
Loans Payable | Loan-to-Value Ratio | Residential | Discounted Cash Flow | Weighted Average
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans Payable	0.478	0.481
Loans Payable | Loan-to-Value Ratio | Residential | Net Present Value | Minimum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans Payable	0.302	0.319
Loans Payable | Loan-to-Value Ratio | Residential | Net Present Value | Maximum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans Payable	0.690	0.636
Loans Payable | Loan-to-Value Ratio | Residential | Net Present Value | Weighted Average
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans Payable	0.478	0.481
Loans Payable | Loan-to-Value Ratio | Retail | Discounted Cash Flow | Minimum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans Payable	0.333	0.319
Loans Payable | Loan-to-Value Ratio | Retail | Discounted Cash Flow | Maximum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans Payable	0.633	0.553
Loans Payable | Loan-to-Value Ratio | Retail | Discounted Cash Flow | Weighted Average
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans Payable	0.411	0.393
Loans Payable | Loan-to-Value Ratio | Retail | Net Present Value | Minimum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans Payable	0.333	0.319
Loans Payable | Loan-to-Value Ratio | Retail | Net Present Value | Maximum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans Payable	0.633	0.553
Loans Payable | Loan-to-Value Ratio | Retail | Net Present Value | Weighted Average
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans Payable	0.411	0.393
Loans Payable | Loan-to-Value Ratio | Office and Industrial | Discounted Cash Flow | Minimum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans Payable	0.316	0.364
Loans Payable | Loan-to-Value Ratio | Office and Industrial | Discounted Cash Flow | Maximum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans Payable	0.595	0.678
Loans Payable | Loan-to-Value Ratio | Office and Industrial | Discounted Cash Flow | Weighted Average
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans Payable	0.463	0.476
Loans Payable | Loan-to-Value Ratio | Office and Industrial | Net Present Value | Minimum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans Payable	0.316	0.364
Loans Payable | Loan-to-Value Ratio | Office and Industrial | Net Present Value | Maximum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans Payable	0.595	0.678
Loans Payable | Loan-to-Value Ratio | Office and Industrial | Net Present Value | Weighted Average
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans Payable	0.463	0.476
Loans Payable | Equivalency Rate | Residential | Discounted Cash Flow | Minimum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans Payable	0.030	0.034
Loans Payable | Equivalency Rate | Residential | Discounted Cash Flow | Maximum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans Payable	0.036	0.046
Loans Payable | Equivalency Rate | Residential | Discounted Cash Flow | Weighted Average
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans Payable	0.033	0.041
Loans Payable | Equivalency Rate | Retail | Discounted Cash Flow | Minimum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans Payable	0.033	0.043
Loans Payable | Equivalency Rate | Retail | Discounted Cash Flow | Maximum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans Payable	0.040	0.053
Loans Payable | Equivalency Rate | Retail | Discounted Cash Flow | Weighted Average
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans Payable	0.035	0.045
Loans Payable | Equivalency Rate | Office and Industrial | Discounted Cash Flow | Minimum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans Payable	0.031	0.039
Loans Payable | Equivalency Rate | Office and Industrial | Discounted Cash Flow | Maximum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans Payable	0.043	0.062
Loans Payable | Equivalency Rate | Office and Industrial | Discounted Cash Flow | Weighted Average
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans Payable	0.034	0.046
Loans Payable | Weighted Average Cost of Capital Risk Premium Multiple | Residential | Net Present Value | Minimum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans Payable	1.20	1.10
Loans Payable | Weighted Average Cost of Capital Risk Premium Multiple | Residential | Net Present Value | Maximum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans Payable	1.70	1.40
Loans Payable | Weighted Average Cost of Capital Risk Premium Multiple | Residential | Net Present Value | Weighted Average
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans Payable	1.30	1.20
Loans Payable | Weighted Average Cost of Capital Risk Premium Multiple | Retail | Net Present Value | Minimum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans Payable	1.20	1.10
Loans Payable | Weighted Average Cost of Capital Risk Premium Multiple | Retail | Net Present Value | Maximum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans Payable	1.50	1.30
Loans Payable | Weighted Average Cost of Capital Risk Premium Multiple | Retail | Net Present Value | Weighted Average
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans Payable	1.30	1.20
Loans Payable | Weighted Average Cost of Capital Risk Premium Multiple | Office and Industrial | Net Present Value | Minimum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans Payable	1.20	1.20
Loans Payable | Weighted Average Cost of Capital Risk Premium Multiple | Office and Industrial | Net Present Value | Maximum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans Payable	1.50	1.40
Loans Payable | Weighted Average Cost of Capital Risk Premium Multiple | Office and Industrial | Net Present Value | Weighted Average
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans Payable	1.30	1.30
Loans Receivable | Loan-to-Value Ratio | Residential, Industrial, Office, Retail and Storage | Discounted Cash Flow | Minimum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans Receivable, including those with related parties		0.708
Loans Receivable | Loan-to-Value Ratio | Residential, Industrial, Office, Retail and Storage | Discounted Cash Flow | Maximum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans Receivable, including those with related parties		0.792
Loans Receivable | Loan-to-Value Ratio | Residential, Industrial, Office, Retail and Storage | Discounted Cash Flow | Weighted Average
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans Receivable, including those with related parties		0.756
Loans Receivable | Equivalency Rate | Residential, Industrial, Office, Retail and Storage | Discounted Cash Flow | Minimum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans Receivable, including those with related parties		0.060
Loans Receivable | Equivalency Rate | Residential, Industrial, Office, Retail and Storage | Discounted Cash Flow | Maximum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans Receivable, including those with related parties		0.083
Loans Receivable | Equivalency Rate | Residential, Industrial, Office, Retail and Storage | Discounted Cash Flow | Weighted Average
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans Receivable, including those with related parties		0.069
Loans Receivable, including those with related parties | Loan-to-Value Ratio | Residential, Hotel, Industrial, Office, Retail and Storage | Discounted Cash Flow | Minimum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans Receivable, including those with related parties	0.317
Loans Receivable, including those with related parties | Loan-to-Value Ratio | Residential, Hotel, Industrial, Office, Retail and Storage | Discounted Cash Flow | Maximum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans Receivable, including those with related parties	0.815
Loans Receivable, including those with related parties | Loan-to-Value Ratio | Residential, Hotel, Industrial, Office, Retail and Storage | Discounted Cash Flow | Weighted Average
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans Receivable, including those with related parties	0.725
Loans Receivable, including those with related parties | Equivalency Rate | Residential, Hotel, Industrial, Office, Retail and Storage | Discounted Cash Flow | Minimum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans Receivable, including those with related parties	0.032
Loans Receivable, including those with related parties | Equivalency Rate | Residential, Hotel, Industrial, Office, Retail and Storage | Discounted Cash Flow | Maximum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans Receivable, including those with related parties	0.084
Loans Receivable, including those with related parties | Equivalency Rate | Residential, Hotel, Industrial, Office, Retail and Storage | Discounted Cash Flow | Weighted Average
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans Receivable, including those with related parties	0.060

Assets and Liabilities Measur_6

Assets and Liabilities Measured at Fair Value on a Recurring Basis - Schedule of net unrealized gains included in changes in net assets attributable to investments and mortgage loans payable (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total net realized and unrealized gains included in changes in net assets	$ 256.4	$ 363.7
Mortgage Loans Payable
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total realized and unrealized gains, still held, included in changes in net assets	(96.8)	86.2
Real Estate Properties
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total net realized and unrealized gains included in changes in net assets	355.2	282.6
Real Estate Joint Ventures
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total net realized and unrealized gains included in changes in net assets	(94.7)	80.8
Loans Receivable
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total net realized and unrealized gains included in changes in net assets	$ (4.1)	$ 0.3

Investments in Joint Ventures_2

Investments in Joint Ventures (Details)	Dec. 31, 2019
Equity Method Investments and Joint Ventures [Abstract]
Minimum percentage of noncontrolling ownership interest in joint ventures, percent	33.30%
Maximum percentage of noncontrolling ownership interest in joint ventures, percent	98.00%

Investments in Joint Ventures -

Investments in Joint Ventures - Schedule of financial position of the joint ventures (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Assets
Real estate properties, at fair value	$ 17,455.8	$ 16,134.1
Other assets	485.9	460.3
Total assets	17,941.7	16,594.4
Liabilities & Equity
Mortgage notes payable and other obligations, at fair value	5,185.3	5,035.3
Other liabilities	256.3	262.5
Total liabilities	5,441.6	5,297.8
Total equity	12,500.1	11,296.6
Total liabilities and equity	$ 17,941.7	$ 16,594.4

Investments in Joint Ventures_3

Investments in Joint Ventures - Schedule of results of operations of the joint ventures (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Operating Revenue and Expenses
Revenues	$ 1,126.5	$ 950.6	$ 869.2
Expenses	604.1	487.1	426.9
Excess of revenues over expenses	$ 522.4	$ 463.5	$ 442.3

Investments in Real Estate Fu_3

Investments in Real Estate Funds (Details) - Variable Interest Entity, Not Primary Beneficiary $ in Millions	12 Months Ended
	Dec. 31, 2019USD ($)
Variable Interest Entity [Line Items]
Carrying Amount	$ 311.8
Maximum Exposure to Loss	$ 311.8
LCS SHIP Venture I, LLC
Variable Interest Entity [Line Items]
Account Interest	90.00%
Carrying Amount	$ 216.1
Maximum Exposure to Loss	$ 216.1
SP V - II, LLC
Variable Interest Entity [Line Items]
Account Interest	75.00%
Carrying Amount	$ 23.3
Maximum Exposure to Loss	$ 23.3
Taconic New York City GP Fund, LP
Variable Interest Entity [Line Items]
Account Interest	60.00%
Carrying Amount	$ 29.8
Maximum Exposure to Loss	$ 29.8
Veritas Trophy VI, LLC
Variable Interest Entity [Line Items]
Account Interest	90.00%
Carrying Amount	$ 4.2
Maximum Exposure to Loss	$ 4.2
IDR - Core Property Index Fund, LLC
Variable Interest Entity [Line Items]
Account Interest	2.00%
Carrying Amount	$ 25
Maximum Exposure to Loss	$ 25
Grubb Southeast Real Estate Fund VI, LLC
Variable Interest Entity [Line Items]
Account Interest	67.00%
Carrying Amount	$ 13.4
Maximum Exposure to Loss	$ 13.4

Loans Receivable - Scheduled of

Loans Receivable - Scheduled of loans receivable by property type (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Fair Value	$ 1,572.1	$ 913
Percentage	100.00%
Credit Concentration Risk | Loans Receivable
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage	100.00%	100.00%
Office
Accounts, Notes, Loans and Financing Receivable [Line Items]
Fair Value	$ 768	$ 512.1
Office | Credit Concentration Risk | Loans Receivable
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage	48.80%	56.20%
Industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Fair Value	$ 199.6	$ 176.4
Industrial | Credit Concentration Risk | Loans Receivable
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage	12.70%	19.30%
Retail
Accounts, Notes, Loans and Financing Receivable [Line Items]
Fair Value	$ 158.5	$ 101.6
Retail | Credit Concentration Risk | Loans Receivable
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage	10.10%	11.10%
Storage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Fair Value	$ 82	$ 63.2
Storage | Credit Concentration Risk | Loans Receivable
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage	5.20%	6.90%
Apartments
Accounts, Notes, Loans and Financing Receivable [Line Items]
Fair Value	$ 228.8	$ 59.7
Apartments | Credit Concentration Risk | Loans Receivable
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage	14.60%	6.50%
Hotel
Accounts, Notes, Loans and Financing Receivable [Line Items]
Fair Value	$ 135.2	$ 0
Hotel | Credit Concentration Risk | Loans Receivable
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage	8.60%	0.00%

Loans Receivable - Schedule of

Loans Receivable - Schedule of fair values and risk ratings (Details) $ in Millions	12 Months Ended
	Dec. 31, 2019USD ($)loan	Dec. 31, 2018USD ($)
Financing Receivable, Credit Quality Indicator [Line Items]
Number of Loans	27
Fair Value | $	$ 1,572.1	$ 913
Percentage	100.00%
Loans Receivable | Credit Concentration Risk
Financing Receivable, Credit Quality Indicator [Line Items]
Percentage	100.00%	100.00%
AA
Financing Receivable, Credit Quality Indicator [Line Items]
Number of Loans	1
Fair Value | $	$ 48.3
AA | Loans Receivable | Credit Concentration Risk
Financing Receivable, Credit Quality Indicator [Line Items]
Percentage	3.10%
BBB
Financing Receivable, Credit Quality Indicator [Line Items]
Number of Loans	7
Fair Value | $	$ 456.1
BBB | Loans Receivable | Credit Concentration Risk
Financing Receivable, Credit Quality Indicator [Line Items]
Percentage	29.00%
BB
Financing Receivable, Credit Quality Indicator [Line Items]
Number of Loans	13
Fair Value | $	$ 787.4
BB | Loans Receivable | Credit Concentration Risk
Financing Receivable, Credit Quality Indicator [Line Items]
Percentage	50.10%
B
Financing Receivable, Credit Quality Indicator [Line Items]
Number of Loans	3
Fair Value | $	$ 205
B | Loans Receivable | Credit Concentration Risk
Financing Receivable, Credit Quality Indicator [Line Items]
Percentage	13.00%
NR
Financing Receivable, Credit Quality Indicator [Line Items]
Number of Loans	3
Fair Value | $	$ 75.3
NR | Loans Receivable | Credit Concentration Risk
Financing Receivable, Credit Quality Indicator [Line Items]
Percentage	4.80%
Related Party
Financing Receivable, Credit Quality Indicator [Line Items]
Number of loans collateralized by interest in a joint venture	2
Unaffiliated Entity
Financing Receivable, Credit Quality Indicator [Line Items]
Number of loans collateralized by interest in a joint venture	1

Loans Receivable (Details)

Loans Receivable (Details)	Dec. 31, 2019loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of loans	27
Nonperforming Status
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of loans	0

Loans Payable - Schedule of out

Loans Payable - Schedule of outstanding mortgage loans payable secured by properties (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Mortgage Loans Payable - Schedule of outstanding mortgage loans payable secured by properties [Line Items]
Principal Amounts Outstanding	$ 2,338	$ 2,688.1
Fair Value Adjustment	27	(80.1)
Total mortgage loans payable	$ 2,365	2,608
Mass Court
Mortgage Loans Payable - Schedule of outstanding mortgage loans payable secured by properties [Line Items]
Interest Rate and Payment Frequency	2.88% paid monthly
Principal Amounts Outstanding	$ 0	90.2
Maturity	Sep. 1, 2019
Annual interest rate	2.88%
Red Canyon at Palomino Park
Mortgage Loans Payable - Schedule of outstanding mortgage loans payable secured by properties [Line Items]
Interest Rate and Payment Frequency	5.34% paid monthly
Principal Amounts Outstanding	$ 27.1	27.1
Maturity	Aug. 1, 2020
Annual interest rate	5.34%
Green River at Palomino Park
Mortgage Loans Payable - Schedule of outstanding mortgage loans payable secured by properties [Line Items]
Interest Rate and Payment Frequency	5.34% paid monthly
Principal Amounts Outstanding	$ 33.2	33.2
Maturity	Aug. 1, 2020
Annual interest rate	5.34%
Blue Ridge at Palomino Park
Mortgage Loans Payable - Schedule of outstanding mortgage loans payable secured by properties [Line Items]
Interest Rate and Payment Frequency	5.34% paid monthly
Principal Amounts Outstanding	$ 33.4	33.4
Maturity	Aug. 1, 2020
Annual interest rate	5.34%
Ashford Meadows Apartments
Mortgage Loans Payable - Schedule of outstanding mortgage loans payable secured by properties [Line Items]
Interest Rate and Payment Frequency	5.17% paid monthly
Principal Amounts Outstanding	$ 44.6	44.6
Maturity	Aug. 1, 2020
Annual interest rate	5.17%
The Knoll
Mortgage Loans Payable - Schedule of outstanding mortgage loans payable secured by properties [Line Items]
Interest Rate and Payment Frequency	3.98% paid monthly
Principal Amounts Outstanding	$ 16.4	16.9
Maturity	Dec. 5, 2020
Annual interest rate	3.98%
Ascent at Windward
Mortgage Loans Payable - Schedule of outstanding mortgage loans payable secured by properties [Line Items]
Interest Rate and Payment Frequency	3.51% paid monthly
Principal Amounts Outstanding	$ 34.6	34.6
Maturity	Jan. 1, 2022
Annual interest rate	3.51%
The Palatine
Mortgage Loans Payable - Schedule of outstanding mortgage loans payable secured by properties [Line Items]
Interest Rate and Payment Frequency	4.25% paid monthly
Principal Amounts Outstanding	$ 75.9	77.4
Maturity	Jan. 10, 2022
Annual interest rate	4.25%
The Forum at Carlsbad
Mortgage Loans Payable - Schedule of outstanding mortgage loans payable secured by properties [Line Items]
Interest Rate and Payment Frequency	4.25% paid monthly
Principal Amounts Outstanding	$ 85.7	87.3
Maturity	Mar. 1, 2022
Annual interest rate	4.25%
Fusion 1560
Mortgage Loans Payable - Schedule of outstanding mortgage loans payable secured by properties [Line Items]
Interest Rate and Payment Frequency	3.42% paid monthly
Principal Amounts Outstanding	$ 37.4	37.4
Maturity	Jun. 10, 2022
Annual interest rate	3.42%
San Diego Office Portfolio
Mortgage Loans Payable - Schedule of outstanding mortgage loans payable secured by properties [Line Items]
Interest Rate and Payment Frequency	3.62% paid monthly
Principal Amounts Outstanding, Loans Payable	$ 48.2	0
Maturity, Loans Payable	Aug. 15, 2022
Annual interest rate	3.62%
The Colorado
Mortgage Loans Payable - Schedule of outstanding mortgage loans payable secured by properties [Line Items]
Interest Rate and Payment Frequency	3.69% paid monthly
Principal Amounts Outstanding	$ 88.1	89.9
Maturity	Nov. 1, 2022
Annual interest rate	3.69%
The Legacy at Westwood
Mortgage Loans Payable - Schedule of outstanding mortgage loans payable secured by properties [Line Items]
Interest Rate and Payment Frequency	3.69% paid monthly
Principal Amounts Outstanding	$ 44.9	45.8
Maturity	Nov. 1, 2022
Annual interest rate	3.69%
Regents Court
Mortgage Loans Payable - Schedule of outstanding mortgage loans payable secured by properties [Line Items]
Interest Rate and Payment Frequency	3.69% paid monthly
Principal Amounts Outstanding	$ 38.1	38.8
Maturity	Nov. 1, 2022
Annual interest rate	3.69%
Fourth & Madison | Loan A
Mortgage Loans Payable - Schedule of outstanding mortgage loans payable secured by properties [Line Items]
Interest Rate and Payment Frequency	3.75% paid monthly
Principal Amounts Outstanding	$ 0	198.2
Maturity	Jun. 1, 2023
Annual interest rate	4.17%
Fourth & Madison | Loan B
Mortgage Loans Payable - Schedule of outstanding mortgage loans payable secured by properties [Line Items]
Interest Rate and Payment Frequency	4.17% paid monthly
Principal Amounts Outstanding	$ 0	90
Maturity	Jun. 1, 2023
Annual interest rate	4.17%
1001 Pennsylvania Avenue
Mortgage Loans Payable - Schedule of outstanding mortgage loans payable secured by properties [Line Items]
Interest Rate and Payment Frequency	3.70% paid monthly
Principal Amounts Outstanding	$ 320.7	327
Maturity	Jun. 1, 2023
Annual interest rate	3.70%
Biltmore at Midtown
Mortgage Loans Payable - Schedule of outstanding mortgage loans payable secured by properties [Line Items]
Interest Rate and Payment Frequency	3.94% paid monthly
Principal Amounts Outstanding	$ 36.4	36.4
Maturity	Jul. 5, 2023
Annual interest rate	3.94%
Cherry Knoll
Mortgage Loans Payable - Schedule of outstanding mortgage loans payable secured by properties [Line Items]
Interest Rate and Payment Frequency	3.78% paid monthly
Principal Amounts Outstanding	$ 35.3	35.3
Maturity	Jul. 5, 2023
Annual interest rate	3.78%
Lofts at SoDo
Mortgage Loans Payable - Schedule of outstanding mortgage loans payable secured by properties [Line Items]
Interest Rate and Payment Frequency	3.94% paid monthly
Principal Amounts Outstanding	$ 35.1	35.1
Maturity	Jul. 5, 2023
Annual interest rate	3.94%
1401 H Street, NW
Mortgage Loans Payable - Schedule of outstanding mortgage loans payable secured by properties [Line Items]
Interest Rate and Payment Frequency	3.65% paid monthly
Principal Amounts Outstanding	$ 115	115
Maturity	Nov. 5, 2024
Annual interest rate	3.65%
The District at La Frontera | Loan A
Mortgage Loans Payable - Schedule of outstanding mortgage loans payable secured by properties [Line Items]
Interest Rate and Payment Frequency	3.84% paid monthly
Principal Amounts Outstanding	$ 39.3	0
Maturity	Dec. 1, 2024
Annual interest rate	3.84%
The District at La Frontera | Loan B
Mortgage Loans Payable - Schedule of outstanding mortgage loans payable secured by properties [Line Items]
Interest Rate and Payment Frequency	4.96% paid monthly
Principal Amounts Outstanding	$ 4.4	0
Maturity	Dec. 1, 2024
Annual interest rate	4.96%
Circa Green Lake
Mortgage Loans Payable - Schedule of outstanding mortgage loans payable secured by properties [Line Items]
Interest Rate and Payment Frequency	3.71% paid monthly
Principal Amounts Outstanding	$ 52	52
Maturity	Mar. 5, 2025
Annual interest rate	3.71%
Union - South Lake Union
Mortgage Loans Payable - Schedule of outstanding mortgage loans payable secured by properties [Line Items]
Interest Rate and Payment Frequency	3.66% paid monthly
Principal Amounts Outstanding	$ 57	57
Maturity	Mar. 5, 2025
Annual interest rate	3.66%
Holly Street Village
Mortgage Loans Payable - Schedule of outstanding mortgage loans payable secured by properties [Line Items]
Interest Rate and Payment Frequency	3.65% paid monthly
Principal Amounts Outstanding	$ 81	81
Maturity	May 1, 2025
Annual interest rate	3.65%
Township Apartments
Mortgage Loans Payable - Schedule of outstanding mortgage loans payable secured by properties [Line Items]
Interest Rate and Payment Frequency	3.65% paid monthly
Principal Amounts Outstanding	$ 0	49
Maturity	May 1, 2025
Annual interest rate	3.65%
Henley at Kingstowne
Mortgage Loans Payable - Schedule of outstanding mortgage loans payable secured by properties [Line Items]
Interest Rate and Payment Frequency	3.60% paid monthly
Principal Amounts Outstanding	$ 71	0
Maturity	May 1, 2025
Annual interest rate	3.60%
32 South State Street
Mortgage Loans Payable - Schedule of outstanding mortgage loans payable secured by properties [Line Items]
Interest Rate and Payment Frequency	4.48% paid monthly
Principal Amounts Outstanding	$ 24	24
Maturity	Jun. 6, 2025
Annual interest rate	4.48%
Vista Station Office Portfolio | Loan A
Mortgage Loans Payable - Schedule of outstanding mortgage loans payable secured by properties [Line Items]
Interest Rate and Payment Frequency	4.00% paid monthly
Principal Amounts Outstanding	$ 20.5	0
Maturity	Jul. 1, 2025
Annual interest rate	4.00%
Vista Station Office Portfolio | Loan B
Mortgage Loans Payable - Schedule of outstanding mortgage loans payable secured by properties [Line Items]
Interest Rate and Payment Frequency	4.20% paid monthly
Principal Amounts Outstanding	$ 44.7	0
Maturity	Nov. 1, 2025
Annual interest rate	4.20%
780 Third Avenue | Loan A
Mortgage Loans Payable - Schedule of outstanding mortgage loans payable secured by properties [Line Items]
Interest Rate and Payment Frequency	3.55% paid monthly
Principal Amounts Outstanding	$ 150	150
Maturity	Aug. 1, 2025
Annual interest rate	3.55%
780 Third Avenue | Loan B
Mortgage Loans Payable - Schedule of outstanding mortgage loans payable secured by properties [Line Items]
Interest Rate and Payment Frequency	3.55% paid monthly
Principal Amounts Outstanding	$ 20	20
Maturity	Aug. 1, 2025
Annual interest rate	3.55%
701 Brickell Avenue
Mortgage Loans Payable - Schedule of outstanding mortgage loans payable secured by properties [Line Items]
Interest Rate and Payment Frequency	3.66% paid monthly
Principal Amounts Outstanding	$ 184	184
Maturity	Apr. 1, 2026
Annual interest rate	3.66%
55 Second Street
Mortgage Loans Payable - Schedule of outstanding mortgage loans payable secured by properties [Line Items]
Interest Rate and Payment Frequency	3.74% paid monthly
Principal Amounts Outstanding	$ 0	137.5
Maturity	Oct. 1, 2026
Annual interest rate	3.74%
1900 K Street, NW
Mortgage Loans Payable - Schedule of outstanding mortgage loans payable secured by properties [Line Items]
Interest Rate and Payment Frequency	3.93% paid monthly
Principal Amounts Outstanding	$ 163	163
Maturity	Apr. 1, 2028
Annual interest rate	3.93%
99 High Street
Mortgage Loans Payable - Schedule of outstanding mortgage loans payable secured by properties [Line Items]
Interest Rate and Payment Frequency	3.90% paid monthly
Principal Amounts Outstanding	$ 277	$ 277
Maturity	Mar. 1, 2030
Annual interest rate	3.90%

Loans Payable - Schedule of mat

Loans Payable - Schedule of maturities of long-term debt (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Debt Disclosure [Abstract]
2020	$ 170.9
2021	19.7
2022	455.5
2023	418.2
2024	165.4
Thereafter	1,108.3
Total maturities	$ 2,338	$ 2,688.1

Line of Credit (Details)

Line of Credit (Details) - Unsecured Revolving Credit Facility - Line of Credit	Sep. 20, 2018USD ($)loanterminstitution	Dec. 31, 2019USD ($)
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 500,000,000
Number of financial institutions | institution	4
Maximum borrowing capacity, per lender	$ 125,000,000
Number of extension periods | term	2
Extension period	12 months
Additional borrowing capacity	$ 250,000,000
Unused commitment fee, percentage	0.20%
Commitment fee		$ 1,000,000
Line of credit, at fair value		$ 250,000,000
Eurodollar Loan
Debt Instrument [Line Items]
Minimum funding requirement	$ 5,000,000
Line of credit, term (or less)	12 months
Maximum active loan limit | loan	5
Eurodollar Loan | Minimum | Adjusted LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	0.85%
Eurodollar Loan | Maximum | Adjusted LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	1.05%
Alternate Base Rate Loan
Debt Instrument [Line Items]
Minimum funding requirement	$ 5,000,000
Alternate Base Rate Loan | Adjusted LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	1.00%
Alternate Base Rate Loan | Federal Reserve Bank of New York
Debt Instrument [Line Items]
Basis spread on variable rate	0.50%

Financial Highlights - Schedule

Financial Highlights - Schedule of condensed financial information for an accumulation unit of the account (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Per Accumulation Unit Data:
Rental income (in dollars per share)	$ 18.165	$ 17.757	$ 17.132	$ 16.433	$ 15.538
Real estate property level expenses and taxes (in dollars per share)	8.734	8.548	7.722	7.534	7.319
Real estate income, net (in dollars per share)	9.431	9.209	9.410	8.899	8.219
Other income (in dollars per share)	6.752	6.162	4.762	3.594	3.342
Total income (in dollars per share)	16.183	15.371	14.172	12.493	11.561
Expense charges (in dollars per share)	3.439	3.161	3.318	3.290	3.092
Investment income, net (in dollars per share)	12.744	12.210	10.854	9.203	8.469
Net realized and unrealized gain on investments and loans payable (in dollars per share)	10.262	6.877	5.839	9.660	18.911
Net increase in Accumulation Unit Value (in dollars per share)	23.006	19.087	16.693	18.863	27.380
Accumulation Unit Value:
Beginning of period (in dollars per share)	417.416	398.329	381.636	362.773	335.393
End of period (in dollars per share)	$ 440.422	$ 417.416	$ 398.329	$ 381.636	$ 362.773
Total return	5.51%	4.79%	4.37%	5.20%	8.16%
Ratios to Average net Assets:
Expenses	0.78%	0.76%	0.83%	0.86%	0.86%
Investment income, net	2.90%	2.95%	2.72%	2.41%	2.37%
Portfolio turnover rate:
Real estate properties	7.80%	11.80%	2.70%	1.30%	5.70%
Marketable securities	28.70%	5.10%	5.70%	3.50%	10.00%
Accumulation Units outstanding at end of period (millions) (in shares)	60.8	60.7	61.3	62.4	60.4
Net assets end of period (millions)	$ 27,307.9	$ 25,842.6	$ 24,942.6	$ 24,304.7	$ 22,360

Accumulation Units - Schedule o

Accumulation Units - Schedule of changes in the number of accumulation units outstanding (Details) - shares shares in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Outstanding:
Beginning of period (in shares)	60.7	61.3	62.4
Credited for premiums (in shares)	6.2	6.5	6.6
Annuity, other periodic payments, withdrawals and death benefits (in shares)	(6.1)	(7.1)	(7.7)
End of period (in shares)	60.8	60.7	61.3

Commitments and Contingencies -

Commitments and Contingencies - Schedule of limited partners' callable commitments (Details) - USD ($)	1 Months Ended	12 Months Ended
	Aug. 31, 2019	Dec. 31, 2019	Dec. 31, 2018
Limited Partners' Capital Account [Line Items]
TOTAL COMMITMENTS		$ 678,800,000	$ 130,000,000
Real Estate Funds
Limited Partners' Capital Account [Line Items]
TOTAL COMMITMENTS		586,800,000	101,000,000
Real Estate Funds | Taconic New York City GP Fund
Limited Partners' Capital Account [Line Items]
TOTAL COMMITMENTS		11,400,000	26,000,000
Real Estate Funds | LCS SHIP Venture I, LLC
Limited Partners' Capital Account [Line Items]
TOTAL COMMITMENTS		28,100,000	75,000,000
Real Estate Funds | Veritas Trophy VI, LLC
Limited Partners' Capital Account [Line Items]
TOTAL COMMITMENTS		35,800,000	0
Right to call capital, period from initial contribution date	18 months
Reduction to committed capital, if no capital call in initial contribution period	$ 15,000,000
If capital call occurs, modified commitment period, from first call date	3 years
Real Estate Funds | SP V - II, LLC
Limited Partners' Capital Account [Line Items]
TOTAL COMMITMENTS		74,900,000	0
Real Estate Funds | Grubb Southeast Real Estate Fund VI, LLC
Limited Partners' Capital Account [Line Items]
TOTAL COMMITMENTS		86,600,000	0
Real Estate Funds | JCR Capital - REA Preferred Equity Parallel Fund
Limited Partners' Capital Account [Line Items]
TOTAL COMMITMENTS		100,000,000	0
Real Estate Funds | Townsend Strategic Ventures LP
Limited Partners' Capital Account [Line Items]
TOTAL COMMITMENTS		250,000,000	0
Loans Receivable
Limited Partners' Capital Account [Line Items]
TOTAL COMMITMENTS		92,000,000	29,000,000
Loans Receivable | 311 South Wacker Mezzanine
Limited Partners' Capital Account [Line Items]
TOTAL COMMITMENTS		7,600,000	11,900,000
Loans Receivable | Rosemont Towson Mezzanine
Limited Partners' Capital Account [Line Items]
TOTAL COMMITMENTS		1,200,000	2,300,000
Loans Receivable | 1330 Broadway Mezzanine
Limited Partners' Capital Account [Line Items]
TOTAL COMMITMENTS		14,000,000	14,800,000
Loans Receivable | SCG Oakland Portfolio Mezzanine
Limited Partners' Capital Account [Line Items]
TOTAL COMMITMENTS		7,000,000	0
Loans Receivable | BREP VIII Industrial Mezzanine
Limited Partners' Capital Account [Line Items]
TOTAL COMMITMENTS		14,100,000	0
Loans Receivable | San Diego Office Portfolio Senior Loan
Limited Partners' Capital Account [Line Items]
TOTAL COMMITMENTS		10,000,000	0
Loans Receivable | San Diego Office Portfolio Mezzanine
Limited Partners' Capital Account [Line Items]
TOTAL COMMITMENTS		3,300,000	0
Loans Receivable | MRA Hub 34 Holding, LLC
Limited Partners' Capital Account [Line Items]
TOTAL COMMITMENTS		1,500,000	0
Loans Receivable | Liberty Park Mezzanine
Limited Partners' Capital Account [Line Items]
TOTAL COMMITMENTS		5,000,000	0
Loans Receivable | Colony New England Hotel Portfolio Senior Loan
Limited Partners' Capital Account [Line Items]
TOTAL COMMITMENTS		14,100,000	0
Loans Receivable | Colony New England Hotel Portfolio Mezzanine
Limited Partners' Capital Account [Line Items]
TOTAL COMMITMENTS		4,700,000	0
Loans Receivable | Exo Apartments Senior Loan
Limited Partners' Capital Account [Line Items]
TOTAL COMMITMENTS		7,100,000	0
Loans Receivable | Exo Apartments Mezzanine
Limited Partners' Capital Account [Line Items]
TOTAL COMMITMENTS		$ 2,400,000	$ 0

Subsequent Events - Schedule of

Subsequent Events - Schedule of purchases after period end (Details) - Subsequent Event - USD ($) $ in Millions	Mar. 09, 2020	Feb. 19, 2020	Feb. 10, 2020	Jan. 15, 2020
Sole at City Center
Subsequent Event [Line Items]
Ownership Percentage				100.00%
Net Purchase Price				$ 103.6
Park Creek Apartments
Subsequent Event [Line Items]
Ownership Percentage			100.00%
Net Purchase Price			$ 41.7
Warwick Shopping Center
Subsequent Event [Line Items]
Ownership Percentage		100.00%
Net Purchase Price		$ 11.1
Overlook at King of Prussia
Subsequent Event [Line Items]
Ownership Percentage		100.00%
Net Purchase Price		$ 55.1
Shoppes At Lake Mary
Subsequent Event [Line Items]
Ownership Percentage		100.00%
Net Purchase Price		$ 21
Winslow Bay Commons
Subsequent Event [Line Items]
Ownership Percentage		100.00%
Net Purchase Price		$ 50.9
Bellevue Place
Subsequent Event [Line Items]
Ownership Percentage		100.00%
Net Purchase Price		$ 7.8
Eisenhower Crossing
Subsequent Event [Line Items]
Ownership Percentage		100.00%
Net Purchase Price		$ 10.1
Pavilion At Turkey Creek
Subsequent Event [Line Items]
Ownership Percentage		100.00%
Net Purchase Price		$ 49.9
Town And Country
Subsequent Event [Line Items]
Ownership Percentage		100.00%
Net Purchase Price		$ 30.1
Creeks At Virginia Center
Subsequent Event [Line Items]
Ownership Percentage		100.00%
Net Purchase Price		$ 41.7
Alexander Place
Subsequent Event [Line Items]
Ownership Percentage		100.00%
Net Purchase Price		$ 39.9
Market Square
Subsequent Event [Line Items]
Ownership Percentage		100.00%
Net Purchase Price		$ 20.4
Cypress Trace
Subsequent Event [Line Items]
Ownership Percentage		100.00%
Net Purchase Price		$ 39.7
Columbiana Station
Subsequent Event [Line Items]
Ownership Percentage		100.00%
Net Purchase Price		$ 43.8
Village Crossing
Subsequent Event [Line Items]
Ownership Percentage		100.00%
Net Purchase Price		$ 160.7
Birkdale Village
Subsequent Event [Line Items]
Ownership Percentage		100.00%
Net Purchase Price		$ 128.9
Birkdale Village Apartments
Subsequent Event [Line Items]
Ownership Percentage		100.00%
Net Purchase Price		$ 70.8
River Ridge
Subsequent Event [Line Items]
Ownership Percentage		100.00%
Net Purchase Price		$ 28
Woodstock Square
Subsequent Event [Line Items]
Ownership Percentage		100.00%
Net Purchase Price		$ 33.7
Newnan Pavilion
Subsequent Event [Line Items]
Ownership Percentage		100.00%
Net Purchase Price		$ 39.7
Marketplace at Mill Creek
Subsequent Event [Line Items]
Ownership Percentage		100.00%
Net Purchase Price		$ 71.5
Heritage Pavilion
Subsequent Event [Line Items]
Ownership Percentage		100.00%
Net Purchase Price		$ 41.6
Fayette Pavilion
Subsequent Event [Line Items]
Ownership Percentage		100.00%
Net Purchase Price		$ 88.4
SITE Centers Corp in DDRTC Core Retail Fund, LLC
Subsequent Event [Line Items]
Ownership Percentage		15.00%
Pacific City
Subsequent Event [Line Items]
Ownership Percentage	100.00%
Net Purchase Price	$ 153.9
DJM Capital in PC Borrower, LLC
Subsequent Event [Line Items]
Ownership Percentage	30.00%

Subsequent Events - Schedule _2

Subsequent Events - Schedule of sales after period end (Details) - Subsequent Event - USD ($) $ in Millions	Mar. 09, 2020	Feb. 19, 2020	Jan. 15, 2020	Jan. 14, 2020	Jan. 08, 2020
The Woodley
Subsequent Event [Line Items]
Ownership Percentage					100.00%
Net Sales Price					$ 176.7
Realized Gain (Loss) on Sale					$ (25.2)
Beltway North Commerce Center
Subsequent Event [Line Items]
Ownership Percentage				100.00%
Net Sales Price				$ 29.8
Realized Gain (Loss) on Sale				$ 4.3
250 North 10th Street
Subsequent Event [Line Items]
Ownership Percentage			100.00%
Net Sales Price			$ 137.1
Realized Gain (Loss) on Sale			$ (37.6)
DDRTC Core Retail Fund, LLC
Subsequent Event [Line Items]
Ownership Percentage		85.00%
Net Sales Price		$ 932.8
Realized Gain (Loss) on Sale		$ (422.2)
SITE Centers Corp in DDRTC Core Retail Fund, LLC
Subsequent Event [Line Items]
Ownership Percentage		15.00%
DJM Capital in PC Borrower, LLC
Subsequent Event [Line Items]
Ownership Percentage	30.00%
PC Borrower, LLC
Subsequent Event [Line Items]
Ownership Percentage	70.00%
Net Sales Price	$ 107.7
Realized Gain (Loss) on Sale	$ (31.3)

Subsequent Events - Schedule _3

Subsequent Events - Schedule of loans receivable after period end (Details) - Subsequent Event - USD ($) $ in Millions	Mar. 09, 2020	Jan. 30, 2020	Jan. 07, 2020
Sol Y Luna
Subsequent Event [Line Items]
Interest Rate			6.55%
Loans Receivable, Originations and purchases, Amount			$ 53
Crest at Las Colinas Station Mezzanine
Subsequent Event [Line Items]
Loans Receivable, Payoffs and sales, Amount		$ 20
Crest at Las Colinas Station Mezzanine | LIBOR
Subsequent Event [Line Items]
Interest Rate		5.11%
DJM Capital Partners Mezzanine
Subsequent Event [Line Items]
Interest Rate	5.00%
Loans Receivable, Payoffs and sales, Amount	$ 6.3

Subsequent Events - Schedule _4

Subsequent Events - Schedule of financings after period end (Details) - Subsequent Event - USD ($) $ in Millions	Mar. 09, 2020	Feb. 19, 2020
Overlook at King of Prussia
Subsequent Event [Line Items]
Ownership Percentage		100.00%
Overlook at King of Prussia | Overlook at King of Prussia, King of Prussia, PA | Overlook at King of Prussia | Mortgages
Subsequent Event [Line Items]
Ownership Percentage		100.00%
Interest Rate		3.82%
Amount		$ 40.8
Winslow Bay Commons
Subsequent Event [Line Items]
Ownership Percentage		100.00%
Winslow Bay Commons | Winslow Bay Commons, Mooresville, NC | Winslow Bay Commons | Mortgages
Subsequent Event [Line Items]
Ownership Percentage		100.00%
Interest Rate		3.82%
Amount		$ 25.8
Birkdale Village
Subsequent Event [Line Items]
Ownership Percentage		100.00%
Birkdale Village | Birksdale Village, Huntersville, NC | Birkdale Village | Mortgages
Subsequent Event [Line Items]
Ownership Percentage		100.00%
Interest Rate		4.30%
Amount		$ 78.4
Marketplace at Mill Creek
Subsequent Event [Line Items]
Ownership Percentage		100.00%
Marketplace at Mill Creek | Marketplace at Mill Creek, Buford, GA | Marketplace at Mill Creek | Mortgages
Subsequent Event [Line Items]
Ownership Percentage		100.00%
Interest Rate		3.82%
Amount		$ 39.6
Pacific City
Subsequent Event [Line Items]
Ownership Percentage	100.00%
Pacific City | Pacific City, Huntington Beach, CA | Pacific City | Mortgages
Subsequent Event [Line Items]
Ownership Percentage	100.00%
Amount	$ 105
Pacific City | Pacific City, Huntington Beach, CA | Pacific City | Mortgages | LIBOR
Subsequent Event [Line Items]
Interest Rate	2.00%
PC Borrower, LLC
Subsequent Event [Line Items]
Ownership Percentage	70.00%
Amount	$ 73.5
PC Borrower, LLC | LIBOR
Subsequent Event [Line Items]
Interest Rate	2.00%
DDRTC Core Retail Fund, LLC
Subsequent Event [Line Items]
Ownership Percentage		85.00%
Amount		$ 156.8
SITE Centers Corp in DDRTC Core Retail Fund, LLC
Subsequent Event [Line Items]
Ownership Percentage		15.00%
DJM Capital in PC Borrower, LLC
Subsequent Event [Line Items]
Ownership Percentage	30.00%

Subsequent Events - Financing -

Subsequent Events - Financing - other (Details) $ in Millions	Jan. 21, 2020USD ($)
Subsequent Event | Unsecured Revolving Credit Facility | Line of Credit
Subsequent Event [Line Items]
Amount	$ 250

Subsequent Events - Marketable

Subsequent Events - Marketable securities (Details) $ in Millions	2 Months Ended
	Feb. 29, 2020USD ($)
Subsequent Event
Subsequent Event [Line Items]
Sale, real estate-securities	$ 304