Accounting Policies and Related Matters	12 Months Ended
Dec. 31, 2016
Accounting Policies and Related Matters [Abstract]
Accounting Policies and Related Matters	2. Accounting Policies and Related Matters Principles of Consolidation The consolidated financial statements include the accounts of our wholly-owned subsidiaries and joint venture (“JV”) entities that we control, through voting rights or other means. All material intercompany transactions and balances have been eliminated in consolidation. At inception of JV transactions, we identify entities for which control is achieved through means other than voting rights (“variable interest entities” or “VIEs”) and determine which business enterprise is the primary beneficiary of its operations. A VIE is broadly defined as an entity where either (i) the equity investors as a group, if any, do not have a controlling financial interest, or (ii) the equity investment at risk is insufficient to finance that entity’s activities without additional subordinated financial support. We consolidate investments in VIEs when we are determined to be the primary beneficiary. Accounting Standards Codification Topic 810, Consolidations (“ASC 810”), requires enterprises to perform a qualitative approach to determining whether or not a VIE will need to be consolidated on a continuous basis. This evaluation is based on an enterprise’s ability to direct and influence the activities of a VIE that most significantly impact that entity’s economic performance. For investments in JVs, GAAP may preclude consolidation by the sole general partner in certain circumstances based on the type of rights held by the limited partner(s). We assess the limited partners’ rights and their impact on our consolidation conclusions, and we reassess if there is a change to the terms or in the exercisability of the rights of the limited partners, the sole general partner increases or decreases its ownership of limited partnership interests, or there is an increase or decrease in the number of outstanding limited partnership interests. We similarly evaluate the rights of managing members of limited liability companies. Use of Estimates The preparation of the financial statements in conformity with U.S. generally accepted accounting principles (“U.S. GAAP”) requires us to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. Actual results could differ from those estimates. Revenue Recognition Revenue is recorded in accordance with U.S. GAAP, which requires that revenue be recognized after four basic criteria are met. These four criteria include persuasive evidence of an arrangement, the rendering of service, fixed and determinable income and reasonably assured collectability. Interest income on loans is recognized as earned based upon the principal amount outstanding subject to an evaluation of collectability risk. Substantially all of our operating leases contain escalating rent structures. Leases with fixed annual rental escalators are generally recognized on a straight-line basis over the initial lease period, subject to a collectability assessment. Rental income related to leases with contingent rental escalators is generally recorded based on the contractual cash rental payments due for the period. Leases in our outpatient medical portfolio typically include some form of operating expense reimbursement by the tenant. Certain payments made to operators are treated as lease incentives and amortized as a reduction of revenue over the lease term. We recognize resident fees and services, other than move-in fees, monthly as services are provided. Lease agreements with residents generally have a term of one year and are cancelable by the resident with 30 days’ notice. Cash and Cash Equivalents Cash and cash equivalents consist of all highly liquid investments with an original maturity of three months or less. Restricted Cash Restricted cash primarily consists of amounts held by lenders to provide future payments for real estate taxes, insurance, tenant and capital improvements, amounts held in escrow relating to acquisitions we are entitled to receive over a period of time as outlined in the escrow agreement and net proceeds from property sales that were executed as tax-deferred dispositions. At December 31, 2016, $138,281,000 of sales proceeds is on deposit in an Internal Revenue Code Section 1031 exchange escrow account with a qualified intermediary. Deferred Loan Expenses Deferred loan expenses are costs incurred by us in connection with the issuance, assumption and amendments of debt arrangements. Deferred loan expenses related to debt instruments, excluding the primary unsecured credit facility, are recorded as a reduction of the related debt liability. Deferred loan expenses related to the primary unsecured credit facility are included in other assets. We amortize these costs over the term of the debt using the straight-line method, which approximates the effective interest method. Investments in Unconsolidated Entities Investments in entities that we do not consolidate but have the ability to exercise significant influence over operating and financial policies are reported under the equity method of accounting. Under the equity method, our share of the investee’s earnings or losses is included in our consolidated results of operations. The initial carrying value of investments in unconsolidated entities is based on the amount paid to purchase the entity interest inclusive of transaction costs. To the extent that our cost basis is different from the basis reflected at the entity level, the basis difference is generally amortized over the lives of the related assets and liabilities, and such amortization is included in our share of equity in earnings of the entity. We evaluate our equity method investments for impairment based upon a comparison of the estimated fair value of the equity method investment to its carrying value. When we determine a decline in the estimated fair value of such an investment below its carrying value is other-than-temporary, an impairment is recorded. Marketable Securities We classify marketable securities as available-for-sale. These securities are carried at their fair value with unrealized gains and losses recognized in stockholders’ equity as a component of accumulated other comprehensive income (loss). When we determine declines in fair value of marketable securities are other-than-temporary, a loss is recognized in earnings. Redeemable Noncontrolling Interests Certain noncontrolling interests are redeemable at fair value. Accordingly, we record the carrying amount of the noncontrolling interests at the greater of (i) the initial carrying amount, increased or decreased for the noncontrolling interest’s share of net income or loss and its share of other comprehensive income or loss and dividends or (ii) the redemption value. If it is probable that the interests will be redeemed in the future, we accrete the carrying value to the redemption value over the period until expected redemption, currently a weighted-average period of approximately four years. In accordance with ASC 810, the redeemable noncontrolling interests are classified outside of permanent equity, as a mezzanine item, in the balance sheet. At December 31, 2016, the current redemption value of redeemable noncontrolling interests exceeded the carrying value of $398,433,000 by $70,818,000. During the year ended December 31, 2016, we determined that an immaterial portion of our noncontrolling interests related to a 2015 transaction was misclassified in permanent equity rather than temporary equity based on a redemption feature of the partnership agreement. We have corrected the $114,714,000 misclassification by recording the change in the consolidated statement of equity for the year ended December 31, 2016. During 2014 and 2015, we entered into DownREIT partnerships which give a real estate seller the ability to exchange its property on a tax deferred basis for equity membership interests (“OP units”). The OP units may be redeemed any time following the first anniversary of the date of issuance at the election of the holders for one share of our common stock per unit or, at our option, cash. Real Property Owned Real property developed by us is recorded at cost, including the capitalization of construction period interest. Expenditures for repairs and maintenance are expensed as incurred. Property acquisitions are accounted for as business combinations where we measure the assets acquired, liabilities (including assumed debt and contingencies) and any noncontrolling interests at their fair values on the acquisition date. The cost of real property acquired, which represents substantially all of the purchase price, is allocated to net tangible and identifiable intangible assets based on their respective fair values. These properties are depreciated on a straight-line basis over their estimated useful lives which range from 15 to 40 years for buildings and 5 to 15 years for improvements. Tangible assets primarily consist of land, buildings and improvements, including those related to capital leases. We consider costs incurred in conjunction with re-leasing properties, including tenant improvements and lease commissions, to represent the acquisition of productive assets and, accordingly, such costs are reflected as investment activities in our statement of cash flows. The remaining purchase price is allocated among identifiable intangible assets primarily consisting of the above or below market component of in-place leases and the value associated with the presence of in-place tenants or residents. The value allocable to the above or below market component of the acquired in-place lease is determined based upon the present value (using a discount rate which reflects the risks associated with the acquired leases) of the difference between (i) the contractual amounts to be paid pursuant to the lease over its remaining term, and (ii) management’s estimate of the amounts that would be paid using fair market rates over the remaining term of the lease. The amounts allocated to above market leases are included in acquired lease intangibles and below market leases are included in other liabilities in the balance sheet and are amortized to rental income over the remaining terms of the respective leases. The total amount of other intangible assets acquired is further allocated to in-place lease values and customer relationship values for in-place tenants based on management’s evaluation of the specific characteristics of each tenant’s lease and our overall relationship with that respective tenant. Characteristics considered by management in allocating these values include the nature and extent of our existing business relationships with the tenant, growth prospects for developing new business with the tenant, the tenant’s credit quality and expectations of lease renewals, among other factors. The total amount of other intangible assets acquired is further allocated to in-place lease values for in-place residents with such value representing (i) value associated with lost revenue related to tenant reimbursable operating costs that would be incurred in an assumed re-leasing period, and (ii) value associated with lost rental revenue from existing leases during an assumed re-leasing period. This intangible asset will be amortized over the remaining life of the lease. The net book value of long-lived assets is reviewed quarterly on a property by property basis to determine if facts and circumstances suggest that the assets may be impaired or that the depreciable life may need to be changed. We consider external factors relating to each asset and the existence of a master lease which may link the cash flows of an individual asset to a larger portfolio of assets leased to the same tenant. If these factors and the projected undiscounted cash flows of the asset over the remaining depreciation period indicate that the asset will not be recoverable, the carrying value is reduced to the estimated fair market value. In addition, we are exposed to the risks inherent in concentrating investments in real estate, and in particular, the seniors housing and health care industries. A downturn in the real estate industry could adversely affect the value of our properties and our ability to sell properties for a price or on terms acceptable to us. Capitalization of Construction Period Interest We capitalize interest costs associated with funds used for the construction of properties owned directly by us. The amount capitalized is based upon the balance outstanding during the construction period using the rate of interest which approximates our cost of financing. Our interest expense reflected in the consolidated statements of comprehensive income has been reduced by the amounts capitalized. Gain on Sale of Assets We recognize sales of assets only upon the closing of the transaction with the purchaser. Payments received from purchasers prior to closing are recorded as deposits and classified as other assets on our consolidated balance sheets. Gains on assets sold are recognized using the full accrual method upon closing when (i) the collectability of the sales price is reasonably assured, (ii) we are not obligated to perform significant activities after the sale to earn the profit, (iii) we have received adequate initial investment from the purchaser and (iv) other profit recognition criteria have been satisfied. Gains may be deferred in whole or in part until the sales satisfy the requirements of gain recognition on sales of real estate. Real Estate Loans Receivable Real estate loans receivable consist of mortgage loans and other real estate loans. Interest income on loans is recognized as earned based upon the principal amount outstanding subject to an evaluation of collectability risks. The loans are primarily collateralized by a first, second or third mortgage lien, a leasehold mortgage on, or an assignment of the partnership interest in, the related properties, corporate guaranties and/or personal guaranties. Allowance for Losses on Loans Receivable The allowance for losses on loans receivable is maintained at a level believed adequate to absorb potential losses in our loans receivable. The determination of the allowance is based on a quarterly evaluation of these loans, including general economic conditions and estimated collectability of loan payments. We evaluate the collectability of our loans receivable based on a combination of factors, including, but not limited to, delinquency status, historical loan charge-offs, financial strength of the borrower and guarantors and value of the underlying collateral. If such factors indicate that there is greater risk of loan charge-offs, additional allowances or placement on non-accrual status may be required. A loan is impaired when, based on current information and events, it is probable that we will be unable to collect all amounts due as scheduled according to the contractual terms of the original loan agreement. Consistent with this definition, all loans on non-accrual are deemed impaired. To the extent circumstances improve and the risk of collectability is diminished, we will return these loans to full accrual status. While a loan is on non-accrual status, any cash receipts are applied against the outstanding principal balance. Any loans with collectability concerns are subjected to a projected payoff valuation. The valuation is based on the expected future cash flows and/or the estimated fair value of the underlying collateral. The valuation is compared to the outstanding balance to determine the reserve needed for each loan. We may base our valuation on a loan’s observable market price, if any, or the fair value of collateral, net of sales costs, if the repayment of the loan is expected to be provided solely by the collateral. Goodwill We account for goodwill in accordance with U.S. GAAP. Goodwill is tested annually for impairment and is tested for impairment more frequently if events and circumstances indicate that the asset might be impaired. An impairment loss is recognized to the extent that the carrying amount, including goodwill, exceeds the reporting unit’s fair value and the implied fair value of goodwill is less than the carrying amount of that goodwill. We have not had any goodwill impairments. Fair Value of Derivative Instruments Derivatives are recorded at fair value on the balance sheet as assets or liabilities. The valuation of derivative instruments requires us to make estimates and judgments that affect the fair value of the instruments. Fair values of our derivatives are estimated by pricing models that consider the forward yield curves and discount rates. The fair value of our forward exchange contracts are estimated by pricing models that consider foreign currency spot rates, forward trade rates and discount rates. Such amounts and the recognition of such amounts are subject to significant estimates that may change in the future. See Note 11 for additional information. Federal Income Tax We have elected to be treated as a REIT under the applicable provisions of the Internal Revenue Code of 1986, as amended (the “Code”), commencing with our first taxable year, and made no provision for federal income tax purposes prior to our acquisition of our “taxable REIT subsidiaries.” As a result of these as well as subsequent acquisitions, we now record income tax expense or benefit with respect to certain of our entities that are taxed as taxable REIT subsidiaries under provisions similar to those applicable to regular corporations and not under the REIT provisions. We account for deferred income taxes using the asset and liability method and recognize deferred tax assets and liabilities for the expected future tax consequences of events that have been included in our financial statements or tax returns. Under this method, we determine deferred tax assets and liabilities based on the differences between the financial reporting and tax bases of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse. Any increase or decrease in the deferred tax liability that results from a change in circumstances, and that causes a change in our judgment about expected future tax consequences of events, is included in the tax provision when such changes occur. Deferred income taxes also reflect the impact of operating loss and tax credit carryforwards. A valuation allowance is provided if we believe it is more likely than not that all or some portion of the deferred tax asset will not be realized. Any increase or decrease in the valuation allowance that results from a change in circumstances, and that causes a change in our judgment about the realizability of the related deferred tax asset, is included in the tax provision when such changes occur. See Note 18 for additional information. Foreign Currency Certain of our subsidiaries’ functional currencies are the local currencies of their respective countries. We translate the results of operations of our foreign subsidiaries into U.S. dollars using average rates of exchange in effect during the period, and we translate balance sheet accounts using exchange rates in effect at the end of the period. We record resulting currency translation adjustments in accumulated other comprehensive income, a component of stockholders’ equity, on our consolidated balance sheets. We record transaction gains and losses in our consolidated statements of comprehensive income. Earnings Per Share Basic earnings per share is computed by dividing net income available to common stockholders by the weighted-average number of shares outstanding for the period adjusted for non-vested shares of restricted stock. The computation of diluted earnings per share is similar to basic earnings per share, except that the number of shares is increased to include the number of additional common shares that would have been outstanding if the potentially dilutive common shares had been issued. Reclassifications Certain amounts in prior years have been reclassified to conform to current year presentation. Immaterial Error Correction During the year ended December 31, 2016, we identified and corrected an immaterial mathematical error in the Consolidated Statement of Comprehensive Income for the years ended December 31, 2015, 2014 and 2013. The error affected only the financial statement line item of “total comprehensive income attributable to stockholders” in the Consolidated Statement of Comprehensive Income. Total comprehensive income and total accumulated comprehensive income for all periods presented were not impacted. Additionally, no other line items within any of the other financial statements and none of the footnotes were impacted. The error resulted in an understatement of total comprehensive income attributable to stockholders of $62,332,000, $29,356,000 and $26,534,000 for the years ended December 31, 2015, 2014 and 2013, respectively. See the Consolidated Statement of Comprehensive Income for corrected total comprehensive income attributable to stockholders. New Accounting Standards In May 2014, the FASB issued ASU No. 2014-09, “Revenue from Contracts with Customers (Topic 606)” (“ASU 2014-09”). The standard is a comprehensive new revenue recognition model that requires revenue to be recognized in a manner to depict the transfer of goods or services to a customer at an amount that reflects the consideration expected to be received in exchange for those goods or services. ASU 2014-09 is effective for fiscal years, and interim periods within those years, beginning after December 15, 2017, and early adoption is permitted beginning after December 15, 2016. A reporting entity may apply the new standard using either a modified retrospective approach by recording a cumulative-effect adjustment to equity as of the beginning of the fiscal year of adoption or a full retrospective approach. We are currently evaluating the impact of the adoption on our consolidated financial statements and have not yet determined the method by which we will adopt the standard. A significant source of revenue for the Company is generated through leasing arrangements, which are specifically excluded from the new standard. We expect that the new standard will affect our accounting policies related to non-lease revenue, including certain fees in our RIDEA joint ventures, common area maintenance in our outpatient medical properties and real estate sales. Under 2014-09, revenue recognition for real estate sales is mainly based on the transfer of control versus current guidance of continuing involvement. We expect that the new guidance will result in more transactions qualifying as sales of real estate and being recognized at an earlier date than under the current guidance. In February 2015, the FASB issued ASU No. 2015-02, “Consolidation (Topic 810): Amendments to the Consolidation Analysis” (“ASU 2015-02”), which makes certain changes to both the variable interest model and the voting interest model, including changes to (1) the identification of variable interests (fees paid to a decision maker or service provider), (2) the variable interest entity characteristics for a limited partnership or similar entity and (3) the primary beneficiary determination. We adopted ASU 2015-02 on January 1, 2016. This guidance did not have a significant impact on our consolidated financial statements. In September 2015, the FASB issued ASU No. 2015-16, “Simplifying the Accounting for Measurement-Period Adjustments” (“ASU 2015-16”) to simplify the accounting for business combinations, specifically as it relates to measurement-period adjustments. Acquiring entities in a business combination must recognize measurement-period adjustments in the reporting period in which the adjustment amounts are determined. Also, ASU 2015-16 requires entities to present separately on the face of the income statement (or disclose in the notes to the financial statements) the portion of the amount recorded in the current period earnings, by line item, that would have been recorded in previous reporting periods if the adjustment to the provisional amounts had been recognized as of the acquisition date. We adopted ASU 2015-16 on January 1, 2016. This guidance did not have a significant impact on our consolidated financial statements. In January 2016, the FASB issued ASU No. 2016-01, “Financial Instruments – Overall: Recognition and Measurement of Financial Assets and Financial Liabilities,” which will require entities to measure their investments at fair value and recognize any changes in fair value in net income unless the investments qualify for the new practicability exception. The practicability exception will be available for equity investments that do not have readily determinable fair values. ASU 2016-01 is effective for fiscal years and interim periods within those years, beginning after December 15, 2017. We are currently evaluating the impact that the standard will have on our consolidated financial statements. In February 2016, the FASB issued ASU No. 2016-02, “Leases (Topic 842),” which requires lessees to recognize assets and liabilities on their balance sheet related to the rights and obligations created by most leases, while continuing to recognize expenses on their income statements over the lease term. It will also require disclosures designed to give financial statement users information regarding amount, timing, and uncertainty of cash flows arising from leases. ASU 2016-02 is effective for fiscal years, and interim periods within those years, beginning after December 15, 2018, and early adoption is permitted. Entities are required to use a modified retrospective approach for leases that exist or are entered into after the beginning of the earliest comparative period in the financial statements. We are currently evaluating the impact of this guidance on our consolidated financial statements. We believe that the adoption of this standard will likely have a material impact to our consolidated balance sheet for the recognition of certain operating leases as right-of-use assets and lease liabilities. Our operating lease obligations are described in Note 12 of the consolidated financial statements. We are in the process of analyzing our lease portfolio and evaluating systems to comply with the standard’s retrospective adoption requirements. In March 2016, the FASB issued ASU No. 2016-09, “Improvements to Employee Share-Based Payment Accounting”. This standard simplifies the accounting treatment for excess tax benefits and deficiencies, forfeitures, and cash flow considerations related to share-based compensation. ASU 2016-09 is effective for fiscal years, and interim periods within those years, beginning after December 15, 2016, and early adoption is permitted. We are currently evaluating the impact of the standard; however, we do not expect its adoption to have a significant impact on our consolidated financial statements. In June 2016, the FASB issued ASU No. 2016-13, “Measurement of Credit Losses on Financial Instruments”. This standard requires a new forward-looking “expected loss” model to be used for receivables, held-to-maturity debt, loans, and other instruments. ASU 2016-13 is effective for fiscal years, and interim periods within those years, beginning after December 15, 2019, and early adoption is permitted for fiscal years beginning after December 15, 2018. We are currently evaluating the impact that the standard will have on our consolidated financial statements. In January 2017, the FASB issued ASU No. 2017-01, “Clarifying the Definition of a Business”. This standard changes the definition of a business to assist entities with evaluating when a set of transferred assets and activities is a business. ASU 2017-01 is effective for fiscal years, and interim periods within those years, beginning after December 15, 2017, and early adoption is permitted. A reporting entity must apply ASU 2017-01 using a prospective approach. Upon adoption, we expect that the majority of our real estate acquisitions will be deemed asset acquisitions rather than business combinations. We will record identifiable assets acquired, liabilities assumed and any noncontrolling interests associated with any asset acquisitions at cost on a relative fair value basis and will capitalize transaction costs. Furthermore, contingent considerations associated with asset acquisitions will be recorded when the contingency is resolved.

2. Accounting Policies and Related Matters

Principles of Consolidation

The consolidated financial statements include the accounts of our wholly-owned subsidiaries and joint venture (“JV”) entities that we control, through voting rights or other means. All material intercompany transactions and balances have been eliminated in consolidation. At inception of JV transactions, we identify entities for which control is achieved through means other than voting rights (“variable interest entities” or “VIEs”) and determine which business enterprise is the primary beneficiary of its operations. A VIE is broadly defined as an entity where either (i) the equity investors as a group, if any, do not have a controlling financial interest, or (ii) the equity investment at risk is insufficient to finance that entity’s activities without additional subordinated financial support. We consolidate investments in VIEs when we are determined to be the primary beneficiary. Accounting Standards Codification Topic 810, Consolidations (“ASC 810”), requires enterprises to perform a qualitative approach to determining whether or not a VIE will need to be consolidated on a continuous basis. This evaluation is based on an enterprise’s ability to direct and influence the activities of a VIE that most significantly impact that entity’s economic performance. For investments in JVs, GAAP may preclude consolidation by the sole general partner in certain circumstances based on the type of rights held by the limited partner(s). We assess the limited partners’ rights and their impact on our consolidation conclusions, and we reassess if there is a change to the terms or in the exercisability of the rights of the limited partners, the sole general partner increases or decreases its ownership of limited partnership interests, or there is an increase or decrease in the number of outstanding limited partnership interests. We similarly evaluate the rights of managing members of limited liability companies.

Use of Estimates

The preparation of the financial statements in conformity with U.S. generally accepted accounting principles (“U.S. GAAP”) requires us to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. Actual results could differ from those estimates.

Revenue Recognition

Revenue is recorded in accordance with U.S. GAAP, which requires that revenue be recognized after four basic criteria are met. These four criteria include persuasive evidence of an arrangement, the rendering of service, fixed and determinable income and reasonably assured collectability. Interest income on loans is recognized as earned based upon the principal amount outstanding subject to an evaluation of collectability risk. Substantially all of our operating leases contain escalating rent structures. Leases with fixed annual rental escalators are generally recognized on a straight-line basis over the initial lease period, subject to a collectability assessment. Rental income related to leases with contingent rental escalators is generally recorded based on the contractual cash rental payments due for the period. Leases in our outpatient medical portfolio typically include some form of operating expense reimbursement by the tenant. Certain payments made to operators are treated as lease incentives and amortized as a reduction of revenue over the lease term. We recognize resident fees and services, other than move-in fees, monthly as services are provided. Lease agreements with residents generally have a term of one year and are cancelable by the resident with 30 days’ notice.

Cash and Cash Equivalents

Cash and cash equivalents consist of all highly liquid investments with an original maturity of three months or less.

Restricted Cash

Restricted cash primarily consists of amounts held by lenders to provide future payments for real estate taxes, insurance, tenant and capital improvements, amounts held in escrow relating to acquisitions we are entitled to receive over a period of time as outlined in the escrow agreement and net proceeds from property sales that were executed as tax-deferred dispositions. At December 31, 2016, $138,281,000 of sales proceeds is on deposit in an Internal Revenue Code Section 1031 exchange escrow account with a qualified intermediary.

Deferred Loan Expenses

Deferred loan expenses are costs incurred by us in connection with the issuance, assumption and amendments of debt arrangements. Deferred loan expenses related to debt instruments, excluding the primary unsecured credit facility, are recorded as a reduction of the related debt liability. Deferred loan expenses related to the primary unsecured credit facility are included in other assets. We amortize these costs over the term of the debt using the straight-line method, which approximates the effective interest method.

Investments in Unconsolidated Entities

Investments in entities that we do not consolidate but have the ability to exercise significant influence over operating and financial policies are reported under the equity method of accounting. Under the equity method, our share of the investee’s earnings or losses is included in our consolidated results of operations. The initial carrying value of investments in unconsolidated entities is based on the amount paid to purchase the entity interest inclusive of transaction costs. To the extent that our cost basis is different from the basis reflected at the entity level, the basis difference is generally amortized over the lives of the related assets and liabilities, and such amortization is included in our share of equity in earnings of the entity. We evaluate our equity method investments for impairment based upon a comparison of the estimated fair value of the equity method investment to its carrying value. When we determine a decline in the estimated fair value of such an investment below its carrying value is other-than-temporary, an impairment is recorded.

Marketable Securities

We classify marketable securities as available-for-sale. These securities are carried at their fair value with unrealized gains and losses recognized in stockholders’ equity as a component of accumulated other comprehensive income (loss). When we determine declines in fair value of marketable securities are other-than-temporary, a loss is recognized in earnings.

Redeemable Noncontrolling Interests

Certain noncontrolling interests are redeemable at fair value. Accordingly, we record the carrying amount of the noncontrolling interests at the greater of (i) the initial carrying amount, increased or decreased for the noncontrolling interest’s share of net income or loss and its share of other comprehensive income or loss and dividends or (ii) the redemption value. If it is probable that the interests will be redeemed in the future, we accrete the carrying value to the redemption value over the period until expected redemption, currently a weighted-average period of approximately four years. In accordance with ASC 810, the redeemable noncontrolling interests are classified outside of permanent equity, as a mezzanine item, in the balance sheet. At December 31, 2016, the current redemption value of redeemable noncontrolling interests exceeded the carrying value of $398,433,000 by $70,818,000.

During the year ended December 31, 2016, we determined that an immaterial portion of our noncontrolling interests related to a 2015 transaction was misclassified in permanent equity rather than temporary equity based on a redemption feature of the partnership agreement. We have corrected the $114,714,000 misclassification by recording the change in the consolidated statement of equity for the year ended December 31, 2016.

During 2014 and 2015, we entered into DownREIT partnerships which give a real estate seller the ability to exchange its property on a tax deferred basis for equity membership interests (“OP units”). The OP units may be redeemed any time following the first anniversary of the date of issuance at the election of the holders for one share of our common stock per unit or, at our option, cash.

Real Property Owned

Real property developed by us is recorded at cost, including the capitalization of construction period interest. Expenditures for repairs and maintenance are expensed as incurred. Property acquisitions are accounted for as business combinations where we measure the assets acquired, liabilities (including assumed debt and contingencies) and any noncontrolling interests at their fair values on the acquisition date. The cost of real property acquired, which represents substantially all of the purchase price, is allocated to net tangible and identifiable intangible assets based on their respective fair values. These properties are depreciated on a straight-line basis over their estimated useful lives which range from 15 to 40 years for buildings and 5 to 15 years for improvements. Tangible assets primarily consist of land, buildings and improvements, including those related to capital leases. We consider costs incurred in conjunction with re-leasing properties, including tenant improvements and lease commissions, to represent the acquisition of productive assets and, accordingly, such costs are reflected as investment activities in our statement of cash flows.

The remaining purchase price is allocated among identifiable intangible assets primarily consisting of the above or below market component of in-place leases and the value associated with the presence of in-place tenants or residents. The value allocable to the above or below market component of the acquired in-place lease is determined based upon the present value (using a discount rate which reflects the risks associated with the acquired leases) of the difference between (i) the contractual amounts to be paid pursuant to the lease over its remaining term, and (ii) management’s estimate of the amounts that would be paid using fair market rates over the remaining term of the lease. The amounts allocated to above market leases are included in acquired lease intangibles and below market leases are included in other liabilities in the balance sheet and are amortized to rental income over the remaining terms of the respective leases.

The total amount of other intangible assets acquired is further allocated to in-place lease values and customer relationship values for in-place tenants based on management’s evaluation of the specific characteristics of each tenant’s lease and our overall relationship with that respective tenant. Characteristics considered by management in allocating these values include the nature and extent of our existing business relationships with the tenant, growth prospects for developing new business with the tenant, the tenant’s credit quality and expectations of lease renewals, among other factors. The total amount of other intangible assets acquired is further allocated to in-place lease values for in-place residents with such value representing (i) value associated with lost revenue related to tenant reimbursable operating costs that would be incurred in an assumed re-leasing period, and (ii) value associated with lost rental revenue from existing leases during an assumed re-leasing period. This intangible asset will be amortized over the remaining life of the lease.

The net book value of long-lived assets is reviewed quarterly on a property by property basis to determine if facts and circumstances suggest that the assets may be impaired or that the depreciable life may need to be changed. We consider external factors relating to each asset and the existence of a master lease which may link the cash flows of an individual asset to a larger portfolio of assets leased to the same tenant. If these factors and the projected undiscounted cash flows of the asset over the remaining depreciation period indicate that the asset will not be recoverable, the carrying value is reduced to the estimated fair market value. In addition, we are exposed to the risks inherent in concentrating investments in real estate, and in particular, the seniors housing and health care industries. A downturn in the real estate industry could adversely affect the value of our properties and our ability to sell properties for a price or on terms acceptable to us.

Capitalization of Construction Period Interest

We capitalize interest costs associated with funds used for the construction of properties owned directly by us. The amount capitalized is based upon the balance outstanding during the construction period using the rate of interest which approximates our cost of financing. Our interest expense reflected in the consolidated statements of comprehensive income has been reduced by the amounts capitalized.

Gain on Sale of Assets

We recognize sales of assets only upon the closing of the transaction with the purchaser. Payments received from purchasers prior to closing are recorded as deposits and classified as other assets on our consolidated balance sheets. Gains on assets sold are recognized using the full accrual method upon closing when (i) the collectability of the sales price is reasonably assured, (ii) we are not obligated to perform significant activities after the sale to earn the profit, (iii) we have received adequate initial investment from the purchaser and (iv) other profit recognition criteria have been satisfied. Gains may be deferred in whole or in part until the sales satisfy the requirements of gain recognition on sales of real estate.

Real Estate Loans Receivable

Real estate loans receivable consist of mortgage loans and other real estate loans. Interest income on loans is recognized as earned based upon the principal amount outstanding subject to an evaluation of collectability risks. The loans are primarily collateralized by a first, second or third mortgage lien, a leasehold mortgage on, or an assignment of the partnership interest in, the related properties, corporate guaranties and/or personal guaranties.

Allowance for Losses on Loans Receivable

The allowance for losses on loans receivable is maintained at a level believed adequate to absorb potential losses in our loans receivable. The determination of the allowance is based on a quarterly evaluation of these loans, including general economic conditions and estimated collectability of loan payments. We evaluate the collectability of our loans receivable based on a combination of factors, including, but not limited to, delinquency status, historical loan charge-offs, financial strength of the borrower and guarantors and value of the underlying collateral. If such factors indicate that there is greater risk of loan charge-offs, additional allowances or placement on non-accrual status may be required. A loan is impaired when, based on current information and events, it is probable that we will be unable to collect all amounts due as scheduled according to the contractual terms of the original loan agreement. Consistent with this definition, all loans on non-accrual are deemed impaired. To the extent circumstances improve and the risk of collectability is diminished, we will return these loans to full accrual status. While a loan is on non-accrual status, any cash receipts are applied against the outstanding principal balance. Any loans with collectability concerns are subjected to a projected payoff valuation. The valuation is based on the expected future cash flows and/or the estimated fair value of the underlying collateral. The valuation is compared to the outstanding balance to determine the reserve needed for each loan. We may base our valuation on a loan’s observable market price, if any, or the fair value of collateral, net of sales costs, if the repayment of the loan is expected to be provided solely by the collateral.

Goodwill

We account for goodwill in accordance with U.S. GAAP. Goodwill is tested annually for impairment and is tested for impairment more frequently if events and circumstances indicate that the asset might be impaired. An impairment loss is recognized to the extent that the carrying amount, including goodwill, exceeds the reporting unit’s fair value and the implied fair value of goodwill is less than the carrying amount of that goodwill. We have not had any goodwill impairments.

Fair Value of Derivative Instruments

Derivatives are recorded at fair value on the balance sheet as assets or liabilities. The valuation of derivative instruments requires us to make estimates and judgments that affect the fair value of the instruments. Fair values of our derivatives are estimated by pricing models that consider the forward yield curves and discount rates. The fair value of our forward exchange contracts are estimated by pricing models that consider foreign currency spot rates, forward trade rates and discount rates. Such amounts and the recognition of such amounts are subject to significant estimates that may change in the future. See Note 11 for additional information.

Federal Income Tax

We have elected to be treated as a REIT under the applicable provisions of the Internal Revenue Code of 1986, as amended (the “Code”), commencing with our first taxable year, and made no provision for federal income tax purposes prior to our acquisition of our “taxable REIT subsidiaries.” As a result of these as well as subsequent acquisitions, we now record income tax expense or benefit with respect to certain of our entities that are taxed as taxable REIT subsidiaries under provisions similar to those applicable to regular corporations and not under the REIT provisions. We account for deferred income taxes using the asset and liability method and recognize deferred tax assets and liabilities for the expected future tax consequences of events that have been included in our financial statements or tax returns. Under this method, we determine deferred tax assets and liabilities based on the differences between the financial reporting and tax bases of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse. Any increase or decrease in the deferred tax liability that results from a change in circumstances, and that causes a change in our judgment about expected future tax consequences of events, is included in the tax provision when such changes occur. Deferred income taxes also reflect the impact of operating loss and tax credit carryforwards. A valuation allowance is provided if we believe it is more likely than not that all or some portion of the deferred tax asset will not be realized. Any increase or decrease in the valuation allowance that results from a change in circumstances, and that causes a change in our judgment about the realizability of the related deferred tax asset, is included in the tax provision when such changes occur. See Note 18 for additional information.

Foreign Currency

Certain of our subsidiaries’ functional currencies are the local currencies of their respective countries. We translate the results of operations of our foreign subsidiaries into U.S. dollars using average rates of exchange in effect during the period, and we translate balance sheet accounts using exchange rates in effect at the end of the period. We record resulting currency translation adjustments in accumulated other comprehensive income, a component of stockholders’ equity, on our consolidated balance sheets. We record transaction gains and losses in our consolidated statements of comprehensive income.

Earnings Per Share

Basic earnings per share is computed by dividing net income available to common stockholders by the weighted-average number of shares outstanding for the period adjusted for non-vested shares of restricted stock. The computation of diluted earnings per share is similar to basic earnings per share, except that the number of shares is increased to include the number of additional common shares that would have been outstanding if the potentially dilutive common shares had been issued.

Reclassifications

Certain amounts in prior years have been reclassified to conform to current year presentation.

Immaterial Error Correction

During the year ended December 31, 2016, we identified and corrected an immaterial mathematical error in the Consolidated Statement of Comprehensive Income for the years ended December 31, 2015, 2014 and 2013. The error affected only the financial statement line item of “total comprehensive income attributable to stockholders” in the Consolidated Statement of Comprehensive Income. Total comprehensive income and total accumulated comprehensive income for all periods presented were not impacted. Additionally, no other line items within any of the other financial statements and none of the footnotes were impacted. The error resulted in an understatement of total comprehensive income attributable to stockholders of $62,332,000, $29,356,000 and $26,534,000 for the years ended December 31, 2015, 2014 and 2013, respectively. See the Consolidated Statement of Comprehensive Income for corrected total comprehensive income attributable to stockholders.

New Accounting Standards

In May 2014, the FASB issued ASU No. 2014-09, “Revenue from Contracts with Customers (Topic 606)” (“ASU 2014-09”). The standard is a comprehensive new revenue recognition model that requires revenue to be recognized in a manner to depict the transfer of goods or services to a customer at an amount that reflects the consideration expected to be received in exchange for those goods or services. ASU 2014-09 is effective for fiscal years, and interim periods within those years, beginning after December 15, 2017, and early adoption is permitted beginning after December 15, 2016. A reporting entity may apply the new standard using either a modified retrospective approach by recording a cumulative-effect adjustment to equity as of the beginning of the fiscal year of adoption or a full retrospective approach. We are currently evaluating the impact of the adoption on our consolidated financial statements and have not yet determined the method by which we will adopt the standard. A significant source of revenue for the Company is generated through leasing arrangements, which are specifically excluded from the new standard. We expect that the new standard will affect our accounting policies related to non-lease revenue, including certain fees in our RIDEA joint ventures, common area maintenance in our outpatient medical properties and real estate sales. Under 2014-09, revenue recognition for real estate sales is mainly based on the transfer of control versus current guidance of continuing involvement. We expect that the new guidance will result in more transactions qualifying as sales of real estate and being recognized at an earlier date than under the current guidance.

In February 2015, the FASB issued ASU No. 2015-02, “Consolidation (Topic 810): Amendments to the Consolidation Analysis” (“ASU 2015-02”), which makes certain changes to both the variable interest model and the voting interest model, including changes to (1) the identification of variable interests (fees paid to a decision maker or service provider), (2) the variable interest entity characteristics for a limited partnership or similar entity and (3) the primary beneficiary determination. We adopted ASU 2015-02 on January 1, 2016. This guidance did not have a significant impact on our consolidated financial statements.

In September 2015, the FASB issued ASU No. 2015-16, “Simplifying the Accounting for Measurement-Period Adjustments” (“ASU 2015-16”) to simplify the accounting for business combinations, specifically as it relates to measurement-period adjustments. Acquiring entities in a business combination must recognize measurement-period adjustments in the reporting period in which the adjustment amounts are determined. Also, ASU 2015-16 requires entities to present separately on the face of the income statement (or disclose in the notes to the financial statements) the portion of the amount recorded in the current period earnings, by line item, that would have been recorded in previous reporting periods if the adjustment to the provisional amounts had been recognized as of the acquisition date. We adopted ASU 2015-16 on January 1, 2016. This guidance did not have a significant impact on our consolidated financial statements.

In January 2016, the FASB issued ASU No. 2016-01, “Financial Instruments – Overall: Recognition and Measurement of Financial Assets and Financial Liabilities,” which will require entities to measure their investments at fair value and recognize any changes in fair value in net income unless the investments qualify for the new practicability exception. The practicability exception will be available for equity investments that do not have readily determinable fair values. ASU 2016-01 is effective for fiscal years and interim periods within those years, beginning after December 15, 2017. We are currently evaluating the impact that the standard will have on our consolidated financial statements.

In February 2016, the FASB issued ASU No. 2016-02, “Leases (Topic 842),” which requires lessees to recognize assets and liabilities on their balance sheet related to the rights and obligations created by most leases, while continuing to recognize expenses on their income statements over the lease term. It will also require disclosures designed to give financial statement users information regarding amount, timing, and uncertainty of cash flows arising from leases. ASU 2016-02 is effective for fiscal years, and interim periods within those years, beginning after December 15, 2018, and early adoption is permitted. Entities are required to use a modified retrospective approach for leases that exist or are entered into after the beginning of the earliest comparative period in the financial statements. We are currently evaluating the impact of this guidance on our consolidated financial statements. We believe that the adoption of this standard will likely have a material impact to our consolidated balance sheet for the recognition of certain operating leases as right-of-use assets and lease liabilities. Our operating lease obligations are described in Note 12 of the consolidated financial statements. We are in the process of analyzing our lease portfolio and evaluating systems to comply with the standard’s retrospective adoption requirements.

In March 2016, the FASB issued ASU No. 2016-09, “Improvements to Employee Share-Based Payment Accounting”. This standard simplifies the accounting treatment for excess tax benefits and deficiencies, forfeitures, and cash flow considerations related to share-based compensation. ASU 2016-09 is effective for fiscal years, and interim periods within those years, beginning after December 15, 2016, and early adoption is permitted. We are currently evaluating the impact of the standard; however, we do not expect its adoption to have a significant impact on our consolidated financial statements.

In June 2016, the FASB issued ASU No. 2016-13, “Measurement of Credit Losses on Financial Instruments”. This standard requires a new forward-looking “expected loss” model to be used for receivables, held-to-maturity debt, loans, and other instruments. ASU 2016-13 is effective for fiscal years, and interim periods within those years, beginning after December 15, 2019, and early adoption is permitted for fiscal years beginning after December 15, 2018. We are currently evaluating the impact that the standard will have on our consolidated financial statements.

In January 2017, the FASB issued ASU No. 2017-01, “Clarifying the Definition of a Business”. This standard changes the definition of a business to assist entities with evaluating when a set of transferred assets and activities is a business. ASU 2017-01 is effective for fiscal years, and interim periods within those years, beginning after December 15, 2017, and early adoption is permitted. A reporting entity must apply ASU 2017-01 using a prospective approach. Upon adoption, we expect that the majority of our real estate acquisitions will be deemed asset acquisitions rather than business combinations. We will record identifiable assets acquired, liabilities assumed and any noncontrolling interests associated with any asset acquisitions at cost on a relative fair value basis and will capitalize transaction costs. Furthermore, contingent considerations associated with asset acquisitions will be recorded when the contingency is resolved.