Description of Business and Significant Accounting Policies	12 Months Ended
Dec. 31, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Description of Business and Significant Accounting Policies	Description of Business and Significant Accounting Policies Description of Business Highwoods Properties, Inc. (the “Company”) is a fully integrated real estate investment trust (“REIT”) that provides leasing, management, development, construction and other customer-related services for its properties and for third parties. The Company conducts its activities through Highwoods Realty Limited Partnership (the “Operating Partnership”). At December 31, 2019, we owned or had an interest in 31.7 million rentable square feet of in-service properties, 1.2 million rentable square feet of office properties under development and approximately 275 acres of development land. The Company is the sole general partner of the Operating Partnership. At December 31, 2019, the Company owned all of the Preferred Units and 103.3 million, or 97.4%, of the Common Units in the Operating Partnership. Limited partners owned the remaining 2.7 million Common Units. In the event the Company issues shares of Common Stock, the net proceeds of the issuance are contributed to the Operating Partnership in exchange for additional Common Units. Generally, the Operating Partnership is obligated to redeem each Common Unit at the request of the holder thereof for cash equal to the value of one share of Common Stock based on the average of the market price for the 10 trading days immediately preceding the notice date of such redemption, provided that the Company, at its option, may elect to acquire any such Common Units presented for redemption for cash or one share of Common Stock. The Common Units owned by the Company are not redeemable. During 2019, the Company redeemed 15,000 Common Units for a like number of shares of Common Stock. Basis of Presentation Our Consolidated Financial Statements are prepared in conformity with accounting principles generally accepted in the United States of America (“GAAP”). The Company's Consolidated Financial Statements include the Operating Partnership, wholly owned subsidiaries and those entities in which the Company has the controlling interest. The Operating Partnership's Consolidated Financial Statements include wholly owned subsidiaries and those entities in which the Operating Partnership has the controlling interest. We consolidate joint venture investments, such as interests in partnerships and limited liability companies, when we control the major operating and financial policies of the investment through majority ownership, in our capacity as a general partner or managing member or through some other contractual right. At December 31, 2019, three properties owned through a joint venture investment were consolidated. We also consolidate those entities deemed to be variable interest entities in which we are determined to be the primary beneficiary. At December 31, 2019, we have involvement with, and are the primary beneficiary in, an entity that we concluded to be a variable interest entity (see Note 4). In addition, during 2019, we acquired a building using a special purpose entity owned by a qualified intermediary to facilitate a potential Section 1031 reverse exchange under the Internal Revenue Code. To realize the tax deferral available under the Section 1031 exchange, we must complete the Section 1031 exchange, and take title to the to-be-exchanged building within 180 days of the acquisition date. We have determined that this entity is a variable interest entity of which we are the primary beneficiary and therefore, we consolidate this entity. As of December 31, 2019, this variable interest entity had total assets, liabilities and cash flows of $425.0 million, $24.0 million and $2.5 million, respectively. All intercompany transactions and accounts have been eliminated. Certain amounts within the Consolidated Statements of Income for the years ended December 31, 2018 and 2017 were removed and/or combined to conform to the current year presentation. Use of Estimates The preparation of consolidated financial statements in accordance with GAAP requires us to make estimates and assumptions that affect the amounts reported in our Consolidated Financial Statements and accompanying notes. Actual results could differ from those estimates. Insurance We are primarily self-insured for health care claims for participating employees. We have stop-loss coverage to limit our exposure to significant claims on a per claim and annual aggregate basis. We determine our liabilities for claims, including incurred but not reported losses, based on all relevant information, including actuarial estimates of claim liabilities. At December 31, 2019, a reserve of $0.6 million was recorded to cover estimated reported and unreported claims. Other Events During the third quarter of 2019, we announced a series of planned investment activities. First, during the fourth quarter of 2019, we acquired Bank of America Tower at Legacy Union in Charlotte’s uptown CBD submarket for a total investment of $436 million. Bank of America Tower at Legacy Union is a trophy, LEED gold-registered office building encompassing 841,000 square feet with structured parking that delivered in 2019. Second, we have a two-phased plan to exit the Greensboro and Memphis markets. The first phase consists of selling a select portfolio of assets in Greensboro and Memphis by mid-2020 with a total sales price that approximates the $436 million total investment for Bank of America Tower at Legacy Union (with the intent of executing a reverse 1031 exchange) and closing the division offices. In 2020, we sold 35 buildings and land in Greensboro for an aggregate sale price of $193.4 million. We can provide no assurances, however, that we will dispose of the remainder of these assets on favorable terms, or at all. The second phase is the planned sale of the remaining assets in both markets. There is no pre-determined timetable for the second phase. As a result of the announced plan to exit the Greensboro and Memphis markets and close our division offices, we recorded $1.8 million of severance costs in 2019. During the first quarter of 2019, Laser Spine Institute, which leased a 176,000 square foot building with structured parking in Tampa’s Westshore submarket, suddenly ceased operations. As a result of this sudden closure, we incurred $5.6 million of credit losses on operating lease receivables and $2.3 million of write-offs of lease incentives (in rental and other revenues), $4.1 million of write-offs of notes receivable (in other income/(loss)) and $11.6 million of write-offs of tenant improvements and deferred leasing costs (in depreciation and amortization). Real Estate and Related Assets Real estate and related assets are recorded at cost and stated at cost less accumulated depreciation. Renovations, replacements and other expenditures that improve or extend the life of assets are capitalized and depreciated over their estimated useful lives. Expenditures for ordinary maintenance and repairs are charged to expense as incurred. Depreciation is computed using the straight-line method over the estimated useful life of 40 years for buildings and depreciable land infrastructure costs, 15 years for building improvements and five to seven years for furniture, fixtures and equipment. Tenant improvements are amortized using the straight-line method over initial fixed terms of the respective leases, which generally are from three to 10 years. Depreciation expense for real estate assets was $214.7 million, $191.0 million and $184.4 million for the years ended December 31, 2019, 2018 and 2017, respectively. Expenditures directly related to the development and construction of real estate assets are included in net real estate assets and are stated at depreciated cost. Development expenditures include pre-construction costs essential to the development of properties, development and construction costs, interest costs on qualifying assets, real estate taxes, development personnel salaries and related costs and other costs incurred during the period of development. Interest and other carrying costs are capitalized until the building is ready for its intended use, but not later than a year from cessation of major construction activity. We consider a construction project as substantially completed and ready for its intended use upon the completion of tenant improvements. We cease capitalization on the portion that is substantially completed and occupied or held available for occupancy and capitalize only those costs associated with the portion under construction. We record liabilities for the performance of asset retirement activities when the obligation to perform such activities is probable even when uncertainty exists about the timing and/or method of settlement. Upon the acquisition of real estate assets accounted for as asset acquisitions, we assess the fair value of acquired tangible assets such as land, buildings and tenant improvements, intangible assets and liabilities such as above and below market leases, acquired in-place leases and other identifiable intangible assets and assumed liabilities. We allocate fair value on a relative basis based on estimated cash flow projections that utilize discount and/or capitalization rates as well as available market information. The fair value of the tangible assets of an acquired property considers the value of the property as if it were vacant. The above and below market rate portions of leases acquired in connection with property acquisitions are recorded in deferred leasing costs and in accounts payable, accrued expenses and other liabilities, respectively, at fair value and amortized into rental revenue over the remaining term of the respective leases as described below. Fair value is calculated as the present value of the difference between (1) the contractual amounts to be paid pursuant to each in-place lease and (2) our estimate of fair market lease rates for each corresponding in-place lease, using a discount rate that reflects the risks associated with the leases acquired and measured over a period equal to the remaining initial term of the lease for above-market leases and the remaining initial term plus the term of any renewal option that the customer would be economically compelled to exercise for below-market leases. In-place leases acquired are recorded at fair value in deferred leasing costs and are amortized to depreciation and amortization expense over the remaining term of the respective lease. The value of in-place leases is based on our evaluation of the specific characteristics of each customer's lease. Factors considered include estimates of carrying costs during hypothetical expected lease-up periods, current market conditions, the customer's credit quality and costs to execute similar leases. In estimating carrying costs, we include real estate taxes, insurance and other operating expenses and estimates of lost rentals at market rates during the expected lease-up periods, depending on local market conditions. In estimating costs to execute similar leases, we consider tenant improvements, leasing commissions and legal and other related expenses. Real estate and other assets are classified as long-lived assets held for use or as long-lived assets held for sale. Real estate is classified as held for sale when the sale of the asset is probable, has been duly approved by the Company, a legally enforceable contract has been executed and the buyer's due diligence period, if any, has expired. Impairments of Real Estate Assets and Investments in Unconsolidated Affiliates With respect to assets classified as held for use, we perform an impairment analysis if our evaluation of events or changes in circumstances indicate that the carrying value may not be recoverable, such as a significant decline in occupancy, identification of materially adverse legal or environmental factors, change in our designation of an asset from core to non-core, which may impact the anticipated holding period, or a decline in market value to an amount less than cost. This analysis is generally performed at the property level, except when an asset is part of an interdependent group such as an office park, and consists of determining whether the asset's carrying amount will be recovered from its undiscounted estimated future operating and residual cash flows. These cash flows are estimated based on a number of assumptions that are subject to economic and market uncertainties including, among others, demand for space, competition for customers, changes in market rental rates, costs to operate each property and expected ownership periods. For properties under development, the cash flows are based on expected service potential of the asset or asset group when development is substantially complete. If the carrying amount of a held for use asset exceeds the sum of its undiscounted future operating and residual cash flows, an impairment loss is recorded for the difference between estimated fair value of the asset and the carrying amount. We generally estimate the fair value of assets held for use by using discounted cash flow analyses. In some instances, appraisal information may be available and is used in addition to a discounted cash flow analysis. As the factors used in generating these cash flows are difficult to predict and are subject to future events that may alter our assumptions, the discounted and/or undiscounted future operating and residual cash flows estimated by us in our impairment analyses or those established by appraisal may not be achieved and we may be required to recognize future impairment losses on properties held for use. We record assets held for sale at the lower of the carrying amount or estimated fair value. Fair value of assets held for sale is equal to the estimated or contracted sales price with a potential buyer, less costs to sell. The impairment loss is the amount by which the carrying amount exceeds the estimated fair value. We also analyze our investments in unconsolidated affiliates for impairment. This analysis consists of determining whether an expected loss in market value of an investment is other than temporary by evaluating the length of time and the extent to which the market value has been less than cost, the financial condition and near-term prospects of the investment, and our intent and ability to retain our investment for a period of time sufficient to allow for any anticipated recovery in market value. As the factors used in this analysis are difficult to predict and are subject to future events that may alter our assumptions, we may be required to recognize future impairment losses on our investments in unconsolidated affiliates. Sales of Real Estate For sales of real estate where we have collected the consideration to which we are entitled in exchange for transferring the real estate, the related assets and liabilities are removed from the balance sheet and the resultant gain or loss is recorded in the period the transaction closes. Any post sale involvement is accounted for as separate performance obligations and when the separate performance obligations are satisfied, the sales price allocated to each is recognized. Leases See Note 2 for significant accounting policies and related disclosures with respect to revenue recognition for our leases, accounting for initial direct costs and lease incentive costs and credit losses on operating lease receivables as a result of the lease standard adoption effective January 1, 2019. Discontinued Operations Properties that are sold or classified as held for sale are classified as discontinued operations provided that the disposal represents a strategic shift that has (or will have) a major effect on our operations and financial results. Interest expense is included in discontinued operations if a related loan securing the sold property is to be paid off or assumed by the buyer in connection with the sale. Investments in Unconsolidated Affiliates We account for our joint venture investments using the equity method of accounting when our interests represent a general partnership interest but substantive participating rights or substantive kick out rights have been granted to the limited partners or when our interests do not represent a general partnership interest and we do not control the major operating and financial policies of the investment. These investments are initially recorded at cost as investments in unconsolidated affiliates and are subsequently adjusted for our share of earnings and cash contributions and distributions. To the extent our cost basis at formation of the joint venture is different than the basis reflected at the joint venture level, the basis difference is amortized over the life of the related assets and included in our share of equity in earnings of unconsolidated affiliates. Cash Equivalents We consider highly liquid investments with an original maturity of three months or less when purchased to be cash equivalents. Restricted Cash Restricted cash represents cash deposits that are legally restricted or held by third parties on our behalf, such as construction-related escrows, property disposition proceeds set aside and designated or intended to fund future tax-deferred exchanges of qualifying real estate investments and escrows and reserves for debt service, real estate taxes and property insurance established pursuant to certain mortgage financing arrangements. Redeemable Common Units and Preferred Units Limited partners holding Common Units other than the Company (“Redeemable Common Units”) have the right to put any and all of the Common Units to the Operating Partnership and the Company has the right to put any and all of the Preferred Units to the Operating Partnership in exchange for their liquidation preference plus accrued and unpaid distributions in the event of a corresponding redemption by the Company of the underlying Preferred Stock. Consequently, these Redeemable Common Units and Preferred Units are classified outside of permanent partners’ capital in the Operating Partnership's accompanying balance sheets. The recorded value of the Redeemable Common Units is based on fair value at the balance sheet date as measured by the closing price of Common Stock on that date multiplied by the total number of Redeemable Common Units outstanding. The recorded value of the Preferred Units is based on their redemption value. Income Taxes The Company has elected and expects to continue to qualify as a REIT under Sections 856 through 860 of the Internal Revenue Code of 1986, as amended (the “Code”). A corporate REIT is a legal entity that holds real estate assets and, through the payment of dividends to stockholders, is generally permitted to reduce or avoid the payment of federal and state income taxes at the corporate level. To maintain qualification as a REIT, the Company is required to pay dividends to its stockholders equal to at least 90.0% of its annual REIT taxable income, excluding net capital gains. The partnership agreement requires the Operating Partnership to pay economically equivalent distributions on outstanding Common Units at the same time that the Company pays dividends on its outstanding Common Stock. Other than income taxes related to its taxable REIT subsidiary, the Operating Partnership does not reflect any federal income taxes in its financial statements, since as a partnership the taxable effects of its operations are attributed to its partners. The Operating Partnership does record state income tax for states that tax partnership income directly. We conduct certain business activities through a taxable REIT subsidiary, as permitted under the Code. The taxable REIT subsidiary is subject to federal, state and local income taxes on its taxable income. We record provisions for income taxes based on its income recognized for financial statement purposes, including the effects of differences between such income and the amount recognized for tax purposes. Concentration of Credit Risk At December 31, 2019, properties that we wholly own were leased to 1,785 customers. The geographic locations that comprise greater than 10.0% of our rental and other revenues are Atlanta, Nashville, Raleigh and Tampa. Our customers engage in a wide variety of businesses. No single customer generated more than 5% of our consolidated revenues during 2019. We maintain our cash and cash equivalents and our restricted cash at financial or other intermediary institutions. The combined account balances at each institution may exceed FDIC insurance coverage and, as a result, there is a concentration of credit risk related to amounts on deposit in excess of FDIC insurance coverage. Additionally, from time to time in connection with tax-deferred 1031 transactions, our restricted cash balances may be commingled with other funds being held by any such intermediary institution, which would subject our balance to the credit risk of the institution. Derivative Financial Instruments We borrow funds at a combination of fixed and variable rates. Borrowings under our revolving credit facility and bank term loans bear interest at variable rates. Our long-term debt, which consists of secured and unsecured long-term financings, typically bears interest at fixed rates. Our interest rate risk management objectives are to limit generally the impact of interest rate changes on earnings and cash flows and lower our overall borrowing costs. To achieve these objectives, from time to time, we enter into interest rate hedge contracts such as collars, swaps, caps and treasury lock agreements in order to mitigate our interest rate risk with respect to existing and prospective debt instruments. We generally do not hold or issue these derivative contracts for trading or speculative purposes. The interest rate on all of our variable rate debt is generally adjusted at one or three month intervals, subject to settlements under these interest rate hedge contracts. Interest rate swaps involve the receipt of variable rate amounts from a counterparty in exchange for making fixed-rate payments over the life of the agreements without exchange of the underlying notional amount. Changes in the fair value of derivatives designated and that qualify as cash flow hedges are recorded in accumulated other comprehensive income/(loss) and are subsequently reclassified into interest expense as interest payments are made on our debt. We account for terminated derivative instruments by recognizing the related accumulated other comprehensive income/(loss) balance in current earnings, unless the hedged forecasted transaction continues as originally planned, in which case we continue to amortize the accumulated other comprehensive income/(loss) into earnings over the originally designated hedge period. Earnings Per Share and Per Unit Basic earnings per share of the Company is computed by dividing net income available for common stockholders by the weighted Common Shares outstanding - basic. Diluted earnings per share is computed by dividing net income available to common stockholders (inclusive of noncontrolling interests in the Operating Partnership) by the weighted Common Shares outstanding - basic plus the dilutive effect of options, warrants and convertible securities outstanding, including Common Units, using the treasury stock method. Weighted Common Shares outstanding - basic includes all unvested restricted stock where dividends received on such restricted stock are non-forfeitable. Basic earnings per unit of the Operating Partnership is computed by dividing net income available for common unitholders by the weighted Common Units outstanding - basic. Diluted earnings per unit is computed by dividing net income available to common unitholders by the weighted Common Units outstanding - basic plus the dilutive effect of options and warrants, using the treasury stock method. Weighted Common Units outstanding - basic includes all of the Company's unvested restricted stock where distributions received on such restricted stock are non-forfeitable. Recently Issued Accounting Standards The Financial Accounting Standards Board ("FASB") issued an accounting standards update ("ASU") that eliminates the requirement to separately measure and report hedge ineffectiveness and generally requires the entire change in the fair value of a hedging instrument to be presented in the same income statement line as the hedged item when the hedged item affects earnings. We adopted the ASU as of January 1, 2019 with no material effect on our Consolidated Financial Statements. The FASB issued an ASU that changes certain disclosure requirements for fair value measurements. The ASU is required to be adopted in 2020 and applied prospectively. We do not expect such adoption to have a material effect on our Notes to Consolidated Financial Statements.

Highwoods Properties, Inc. (the “Company”) is a fully integrated real estate investment trust (“REIT”) that provides leasing, management, development, construction and other customer-related services for its properties and for third parties. The Company conducts its activities through Highwoods Realty Limited Partnership (the “Operating Partnership”). At December 31, 2019, we owned or had an interest in 31.7 million rentable square feet of in-service properties, 1.2 million rentable square feet of office properties under development and approximately 275 acres of development land.

The Company is the sole general partner of the Operating Partnership. At December 31, 2019, the Company owned all of the Preferred Units and 103.3 million, or 97.4%, of the Common Units in the Operating Partnership. Limited partners owned the remaining 2.7 million Common Units. In the event the Company issues shares of Common Stock, the net proceeds of the issuance are contributed to the Operating Partnership in exchange for additional Common Units. Generally, the Operating Partnership is obligated to redeem each Common Unit at the request of the holder thereof for cash equal to the value of one share of Common Stock based on the average of the market price for the 10 trading days immediately preceding the notice date of such redemption, provided that the Company, at its option, may elect to acquire any such Common Units presented for redemption for cash or one share of Common Stock. The Common Units owned by the Company are not redeemable. During 2019, the Company redeemed 15,000 Common Units for a like number of shares of Common Stock.

The Company's Consolidated Financial Statements include the Operating Partnership, wholly owned subsidiaries and those entities in which the Company has the controlling interest. The Operating Partnership's Consolidated Financial Statements include wholly owned subsidiaries and those entities in which the Operating Partnership has the controlling interest. We consolidate joint venture investments, such as interests in partnerships and limited liability companies, when we control the major operating and financial policies of the investment through majority ownership, in our capacity as a general partner or managing member or through some other contractual right. At December 31, 2019, three properties owned through a joint venture investment were consolidated. We also consolidate those entities deemed to be variable interest entities in which we are determined to be the primary beneficiary. At December 31, 2019, we have involvement with, and are the primary beneficiary in, an entity that we concluded to be a variable interest entity (see Note 4).

In addition, during 2019, we acquired a building using a special purpose entity owned by a qualified intermediary to facilitate a potential Section 1031 reverse exchange under the Internal Revenue Code. To realize the tax deferral available under the Section 1031 exchange, we must complete the Section 1031 exchange, and take title to the to-be-exchanged building within 180 days of the acquisition date. We have determined that this entity is a variable interest entity of which we are the primary beneficiary and therefore, we consolidate this entity. As of December 31, 2019, this variable interest entity had total assets, liabilities and cash flows of $425.0 million, $24.0 million and $2.5 million, respectively.

The preparation of consolidated financial statements in accordance with GAAP requires us to make estimates and assumptions that affect the amounts reported in our Consolidated Financial Statements and accompanying notes. Actual results could differ from those estimates.

We are primarily self-insured for health care claims for participating employees. We have stop-loss coverage to limit our exposure to significant claims on a per claim and annual aggregate basis. We determine our liabilities for claims, including incurred but not reported losses, based on all relevant information, including actuarial estimates of claim liabilities. At December 31, 2019, a reserve of $0.6 million was recorded to cover estimated reported and unreported claims.

During the third quarter of 2019, we announced a series of planned investment activities. First, during the fourth quarter of 2019, we acquired Bank of America Tower at Legacy Union in Charlotte’s uptown CBD submarket for a total investment of $436 million. Bank of America Tower at Legacy Union is a trophy, LEED gold-registered office building encompassing 841,000 square feet with structured parking that delivered in 2019. Second, we have a two-phased plan to exit the Greensboro and Memphis markets. The first phase consists of selling a select portfolio of assets in Greensboro and Memphis by mid-2020 with a total sales price that approximates the $436 million total investment for Bank of America Tower at Legacy Union (with the intent of executing a reverse 1031 exchange) and closing the division offices. In 2020, we sold 35 buildings and land in Greensboro for an aggregate sale price of $193.4 million. We can provide no assurances, however, that we will dispose of the remainder of these assets on favorable terms, or at all. The second phase is the planned sale of the remaining assets in both markets. There is no pre-determined timetable for the second phase. As a result of the announced plan to exit the Greensboro and Memphis markets and close our division offices, we recorded $1.8 million of severance costs in 2019.

During the first quarter of 2019, Laser Spine Institute, which leased a 176,000 square foot building with structured parking in Tampa’s Westshore submarket, suddenly ceased operations. As a result of this sudden closure, we incurred $5.6 million of credit losses on operating lease receivables and $2.3 million of write-offs of lease incentives (in rental and other revenues), $4.1 million of write-offs of notes receivable (in other income/(loss)) and $11.6 million of write-offs of tenant improvements and deferred leasing costs (in depreciation and amortization).

Real estate and related assets are recorded at cost and stated at cost less accumulated depreciation. Renovations, replacements and other expenditures that improve or extend the life of assets are capitalized and depreciated over their estimated useful lives. Expenditures for ordinary maintenance and repairs are charged to expense as incurred. Depreciation is computed using the straight-line method over the estimated useful life of 40 years for buildings and depreciable land infrastructure costs, 15 years for building improvements and five to seven years for furniture, fixtures and equipment. Tenant improvements are amortized using the straight-line method over initial fixed terms of the respective leases, which generally are from three to 10 years. Depreciation expense for real estate assets was $214.7 million, $191.0 million and $184.4 million for the years ended December 31, 2019, 2018 and 2017, respectively.

Expenditures directly related to the development and construction of real estate assets are included in net real estate assets and are stated at depreciated cost. Development expenditures include pre-construction costs essential to the development of properties, development and construction costs, interest costs on qualifying assets, real estate taxes, development personnel salaries and related costs and other costs incurred during the period of development. Interest and other carrying costs are capitalized until the building is ready for its intended use, but not later than a year from cessation of major construction activity. We consider a construction project as substantially completed and ready for its intended use upon the completion of tenant improvements. We cease capitalization on the portion that is substantially completed and occupied or held available for occupancy and capitalize only those costs associated with the portion under construction.

acquired in-place leases and other identifiable intangible assets and assumed liabilities. We allocate fair value on a relative basis based on estimated cash flow projections that utilize discount and/or capitalization rates as well as available market information. The fair value of the tangible assets of an acquired property considers the value of the property as if it were vacant.

The above and below market rate portions of leases acquired in connection with property acquisitions are recorded in deferred leasing costs and in accounts payable, accrued expenses and other liabilities, respectively, at fair value and amortized into rental revenue over the remaining term of the respective leases as described below. Fair value is calculated as the present value of the difference between (1) the contractual amounts to be paid pursuant to each in-place lease and (2) our estimate of fair market lease rates for each corresponding in-place lease, using a discount rate that reflects the risks associated with the leases acquired and measured over a period equal to the remaining initial term of the lease for above-market leases and the remaining initial term plus the term of any renewal option that the customer would be economically compelled to exercise for below-market leases.

In-place leases acquired are recorded at fair value in deferred leasing costs and are amortized to depreciation and amortization expense over the remaining term of the respective lease. The value of in-place leases is based on our evaluation of the specific characteristics of each customer's lease. Factors considered include estimates of carrying costs during hypothetical expected lease-up periods, current market conditions, the customer's credit quality and costs to execute similar leases. In estimating carrying costs, we include real estate taxes, insurance and other operating expenses and estimates of lost rentals at market rates during the expected lease-up periods, depending on local market conditions. In estimating costs to execute similar leases, we consider tenant improvements, leasing commissions and legal and other related expenses.

Real estate and other assets are classified as long-lived assets held for use or as long-lived assets held for sale. Real estate is classified as held for sale when the sale of the asset is probable, has been duly approved by the Company, a legally enforceable contract has been executed and the buyer's due diligence period, if any, has expired.

With respect to assets classified as held for use, we perform an impairment analysis if our evaluation of events or changes in circumstances indicate that the carrying value may not be recoverable, such as a significant decline in occupancy, identification of materially adverse legal or environmental factors, change in our designation of an asset from core to non-core, which may impact the anticipated holding period, or a decline in market value to an amount less than cost. This analysis is generally performed at the property level, except when an asset is part of an interdependent group such as an office park, and consists of determining whether the asset's carrying amount will be recovered from its undiscounted estimated future operating and residual cash flows. These cash flows are estimated based on a number of assumptions that are subject to economic and market uncertainties including, among others, demand for space, competition for customers, changes in market rental rates, costs to operate each property and expected ownership periods. For properties under development, the cash flows are based on expected service potential of the asset or asset group when development is substantially complete.

If the carrying amount of a held for use asset exceeds the sum of its undiscounted future operating and residual cash flows, an impairment loss is recorded for the difference between estimated fair value of the asset and the carrying amount. We generally estimate the fair value of assets held for use by using discounted cash flow analyses. In some instances, appraisal information may be available and is used in addition to a discounted cash flow analysis. As the factors used in generating these cash flows are difficult to predict and are subject to future events that may alter our assumptions, the discounted and/or undiscounted future operating and residual cash flows estimated by us in our impairment analyses or those established by appraisal may not be achieved and we may be required to recognize future impairment losses on properties held for use.

We record assets held for sale at the lower of the carrying amount or estimated fair value. Fair value of assets held for sale is equal to the estimated or contracted sales price with a potential buyer, less costs to sell. The impairment loss is the amount by which the carrying amount exceeds the estimated fair value.

We also analyze our investments in unconsolidated affiliates for impairment. This analysis consists of determining whether an expected loss in market value of an investment is other than temporary by evaluating the length of time and the extent to which the market value has been less than cost, the financial condition and near-term prospects of the investment, and our intent and ability to retain our investment for a period of time sufficient to allow for any anticipated recovery in market value. As the factors used in this analysis are difficult to predict and are subject to future events that may alter our assumptions, we may be required to recognize future impairment losses on our investments in unconsolidated affiliates.

For sales of real estate where we have collected the consideration to which we are entitled in exchange for transferring the real estate, the related assets and liabilities are removed from the balance sheet and the resultant gain or loss is recorded in the period the transaction closes. Any post sale involvement is accounted for as separate performance obligations and when the separate performance obligations are satisfied, the sales price allocated to each is recognized.

See Note 2 for significant accounting policies and related disclosures with respect to revenue recognition for our leases, accounting for initial direct costs and lease incentive costs and credit losses on operating lease receivables as a result of the lease standard adoption effective January 1, 2019.

Properties that are sold or classified as held for sale are classified as discontinued operations provided that the disposal represents a strategic shift that has (or will have) a major effect on our operations and financial results. Interest expense is included in discontinued operations if a related loan securing the sold property is to be paid off or assumed by the buyer in connection with the sale.

We account for our joint venture investments using the equity method of accounting when our interests represent a general partnership interest but substantive participating rights or substantive kick out rights have been granted to the limited partners or when our interests do not represent a general partnership interest and we do not control the major operating and financial policies of the investment. These investments are initially recorded at cost as investments in unconsolidated affiliates and are subsequently adjusted for our share of earnings and cash contributions and distributions. To the extent our cost basis at formation of the joint venture is different than the basis reflected at the joint venture level, the basis difference is amortized over the life of the related assets and included in our share of equity in earnings of unconsolidated affiliates.

Restricted cash represents cash deposits that are legally restricted or held by third parties on our behalf, such as construction-related escrows, property disposition proceeds set aside and designated or intended to fund future tax-deferred exchanges of qualifying real estate investments and escrows and reserves for debt service, real estate taxes and property insurance established pursuant to certain mortgage financing arrangements.

Limited partners holding Common Units other than the Company (“Redeemable Common Units”) have the right to put any and all of the Common Units to the Operating Partnership and the Company has the right to put any and all of the Preferred Units to the Operating Partnership in exchange for their liquidation preference plus accrued and unpaid distributions in the event of a corresponding redemption by the Company of the underlying Preferred Stock. Consequently, these Redeemable Common Units and Preferred Units are classified outside of permanent partners’ capital in the Operating Partnership's accompanying balance sheets. The recorded value of the Redeemable Common Units is based on fair value at the balance sheet date as measured by the closing price of Common Stock on that date multiplied by the total number of Redeemable Common Units outstanding. The recorded value of the Preferred Units is based on their redemption value.

The Company has elected and expects to continue to qualify as a REIT under Sections 856 through 860 of the Internal Revenue Code of 1986, as amended (the “Code”). A corporate REIT is a legal entity that holds real estate assets and, through the payment of dividends to stockholders, is generally permitted to reduce or avoid the payment of federal and state income taxes at the corporate level. To maintain qualification as a REIT, the Company is required to pay dividends to its stockholders equal to at least 90.0% of its annual REIT taxable income, excluding net capital gains. The partnership agreement requires the Operating Partnership to pay

Other than income taxes related to its taxable REIT subsidiary, the Operating Partnership does not reflect any federal income taxes in its financial statements, since as a partnership the taxable effects of its operations are attributed to its partners. The Operating Partnership does record state income tax for states that tax partnership income directly.

We conduct certain business activities through a taxable REIT subsidiary, as permitted under the Code. The taxable REIT subsidiary is subject to federal, state and local income taxes on its taxable income. We record provisions for income taxes based on its income recognized for financial statement purposes, including the effects of differences between such income and the amount recognized for tax purposes.

At December 31, 2019, properties that we wholly own were leased to 1,785 customers. The geographic locations that comprise greater than 10.0% of our rental and other revenues are Atlanta, Nashville, Raleigh and Tampa. Our customers engage in a wide variety of businesses. No single customer generated more than 5% of our consolidated revenues during 2019.

We maintain our cash and cash equivalents and our restricted cash at financial or other intermediary institutions. The combined account balances at each institution may exceed FDIC insurance coverage and, as a result, there is a concentration of credit risk related to amounts on deposit in excess of FDIC insurance coverage. Additionally, from time to time in connection with tax-deferred 1031 transactions, our restricted cash balances may be commingled with other funds being held by any such intermediary institution, which would subject our balance to the credit risk of the institution.

We borrow funds at a combination of fixed and variable rates. Borrowings under our revolving credit facility and bank term loans bear interest at variable rates. Our long-term debt, which consists of secured and unsecured long-term financings, typically bears interest at fixed rates. Our interest rate risk management objectives are to limit generally the impact of interest rate changes on earnings and cash flows and lower our overall borrowing costs. To achieve these objectives, from time to time, we enter into interest rate hedge contracts such as collars, swaps, caps and treasury lock agreements in order to mitigate our interest rate risk with respect to existing and prospective debt instruments. We generally do not hold or issue these derivative contracts for trading or speculative purposes. The interest rate on all of our variable rate debt is generally adjusted at one or three month intervals, subject to settlements under these interest rate hedge contracts.

Interest rate swaps involve the receipt of variable rate amounts from a counterparty in exchange for making fixed-rate payments over the life of the agreements without exchange of the underlying notional amount. Changes in the fair value of derivatives designated and that qualify as cash flow hedges are recorded in accumulated other comprehensive income/(loss) and are subsequently reclassified into interest expense as interest payments are made on our debt.

We account for terminated derivative instruments by recognizing the related accumulated other comprehensive income/(loss) balance in current earnings, unless the hedged forecasted transaction continues as originally planned, in which case we continue to amortize the accumulated other comprehensive income/(loss) into earnings over the originally designated hedge period.

Basic earnings per share of the Company is computed by dividing net income available for common stockholders by the weighted Common Shares outstanding - basic. Diluted earnings per share is computed by dividing net income available to common stockholders (inclusive of noncontrolling interests in the Operating Partnership) by the weighted Common Shares outstanding - basic plus the dilutive effect of options, warrants and convertible securities outstanding, including Common Units, using the treasury stock method. Weighted Common Shares outstanding - basic includes all unvested restricted stock where dividends received on such restricted stock are non-forfeitable.

Basic earnings per unit of the Operating Partnership is computed by dividing net income available for common unitholders by the weighted Common Units outstanding - basic. Diluted earnings per unit is computed by dividing net income available to common unitholders by the weighted Common Units outstanding - basic plus the dilutive effect of options and warrants, using the treasury stock method. Weighted Common Units outstanding - basic includes all of the Company's unvested restricted stock where distributions received on such restricted stock are non-forfeitable.

The Financial Accounting Standards Board ("FASB") issued an accounting standards update ("ASU") that eliminates the requirement to separately measure and report hedge ineffectiveness and generally requires the entire change in the fair value of a hedging instrument to be presented in the same income statement line as the hedged item when the hedged item affects earnings. We adopted the ASU as of January 1, 2019 with no material effect on our Consolidated Financial Statements.

The FASB issued an ASU that changes certain disclosure requirements for fair value measurements. The ASU is required to be adopted in 2020 and applied prospectively. We do not expect such adoption to have a material effect on our Notes to Consolidated Financial Statements.