2.SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

A summary of the significant accounting policies applied in the preparation of the accompanying consolidated financial statements is as follows:

Principles of Consolidation

The consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”) and include the Company and its majority and wholly-owned subsidiaries. All significant intercompany accounts and transactions have been eliminated in consolidation.

Use of Estimates

The preparation of the consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying notes. The significant estimates made by management relate to the allowance for doubtful accounts, the costs and revenue relating to the Company’s construction contracts, stock-based compensation assumptions, valuation allowance related to deferred tax assets, fair value of long-lived assets, the useful lives of towers and intangible assets, anticipated property tax assessments, fair value of investments and asset retirement obligations. Management develops estimates based on historical experience and on various assumptions about the future that are believed to be reasonable based on the information available. These estimates ultimately may differ from actual results and such differences could be material.

Cash and Cash Equivalents

Cash and cash equivalents consist primarily of cash in banks, money market funds, commercial paper, highly liquid short-term investments, and other marketable securities with an original maturity of three months or less at the time of purchase. These investments are carried at cost, which approximates fair value.

Restricted Cash

The Company classifies all cash pledged as collateral to secure certain obligations and all cash whose use is limited as restricted cash. This includes cash held in escrow to fund certain reserve accounts relating to the Tower Securities as well as for payment and performance bonds and surety bonds issued for the benefit of the Company in the ordinary course of business, as well as collateral associated with workers’ compensation plans (see Note 4).

Investments

Investment securities with original maturities of more than three months but less than one year at time of purchase are considered short-term investments. The Company’s short-term investments primarily consist of certificates of deposit with maturities of less than a year. Investment securities with maturities of more than a year are considered long-term investments and are classified in other assets on the accompanying Consolidated Balance Sheets. Long-term investments primarily consist of U.S. Treasuries, mutual funds, and preferred securities. Gross purchases and sales of the Company’s investments are presented within “Cash flows from investing activities” on the Company’s Consolidated Statements of Cash Flows.

The Company accounts for its investments in privately held companies under the cost and equity method. The Company evaluates its investments for impairment at least annually. The Company determines the fair value of its investments by considering available evidence, including general market conditions, the investee’s financial condition, near-term prospects, market comparables and subsequent rounds of financing. The Company measures and records its investments at fair value when they are deemed to be other-than-temporarily impaired. The Company did not recognize any impairment loss associated with its investments during the years ended December 31, 2017, 2016, and 2015.

During the years ended December 31, 2017 and 2016, the Company received proceeds related to the sale or maturity of investments of $0.2 million and $0.7 million, respectively. During the year ended December 31, 2017 and 2016, no gain or loss was recorded related to the sale or maturity of investments. The proceeds are reflected in Net cash used in investing activities on the Consolidated Statements of Cash Flows, and the related gain or loss on sale or maturity is reflected in Other income (expense), net in the accompanying Consolidated Statement of Operations. The aggregate carrying value of the Company’s investments was approximately $8.6 million and $8.1 million as of December 31, 2017 and 2016, respectively, and is classified within short-term investments and other assets on the Company’s consolidated balance sheets.

Property and Equipment

Property and equipment are recorded at cost or at estimated fair value (in the case of acquired properties), adjusted for asset impairment and estimated asset retirement obligations. Costs for self-constructed towers include direct materials and labor, indirect costs and capitalized interest. Approximately $1.1 million, $1.0 million, and $0.8 million of interest cost was capitalized in 2017, 2016 and 2015, respectively.

Depreciation on towers and related components is provided using the straight-line method over the estimated useful lives, not to exceed the minimum lease term of the underlying ground lease. The Company defines the minimum lease term as the shorter of the period from lease inception through the end of the term of all tenant lease obligations in existence at ground lease inception, including renewal periods, or the ground lease term, including renewal periods. If no tenant lease obligation exists at the date of ground lease inception, the initial term of the ground lease is considered the minimum lease term. Leasehold improvements are amortized on a straight-line basis over the shorter of the useful life of the improvement or the minimum lease term of the lease. For all other property and equipment, depreciation is provided using the straight-line method over the estimated useful lives.

The Company performs ongoing evaluations of the estimated useful lives of its property and equipment for depreciation purposes. The estimated useful lives are determined and continually evaluated based on the period over which services are expected to be rendered by the asset. If the useful lives of assets are reduced, depreciation may be accelerated in future years. Property and equipment under capital leases are amortized on a straight-line basis over the term of the lease or the remaining estimated life of the leased property, whichever is shorter, and the related amortization is included in depreciation expense. Expenditures for maintenance and repair are expensed as incurred.

Asset classes and related estimated useful lives are as follows:



Towers and related components	3 - 15 years
Furniture, equipment and vehicles	2 - 7 years
Buildings and improvements	10 - 30 years

Betterments, improvements, and significant repairs, which increase the value or extend the life of an asset, are capitalized and depreciated over the estimated useful life of the respective asset. Changes in an asset’s estimated useful life are accounted for prospectively, with the book value of the asset at the time of the change being depreciated over the revised remaining useful life. There has been no material impact for changes in estimated useful lives for any years presented.

Deferred Financing Fees

Financing fees related to the issuance of debt have been deferred and are being amortized using the effective interest rate method over the expected duration of the related indebtedness (see Note 12). For all of the Company’s debt, except for the Revolving Credit Facility where the debt issuance costs are being presented as an asset on the accompanying Consolidated Balance Sheet, debt issuance costs are presented on the balance sheet as a direct deduction from the related debt liability rather than as an asset.

Deferred Lease Costs

The Company defers certain initial direct costs associated with the origination of tenant leases and lease amendments and amortizes these costs over the initial lease term or over the lease term remaining if related to a lease amendment. Such deferred costs were approximately $11.0 million, $10.2 million, and $10.9 million in 2017, 2016, and 2015, respectively. Amortization expense was $13.1 million, $11.3 million, and $9.0 million for the years ended December 31, 2017, 2016 and 2015, respectively, and is included in cost of site leasing on the accompanying Consolidated Statements of Operations. As of December 31, 2017 and 2016, unamortized deferred lease costs were $27.7 million and $29.7 million, respectively, and are included in other assets on the accompanying Consolidated Balance Sheets.

Intangible Assets

The Company classifies as intangible assets the fair value of current leases in place at the acquisition date of towers and related assets (referred to as the “Current contract intangibles”), and the fair value of future tenant leases anticipated to be added to the acquired towers (referred to as the “Network location intangibles”). These intangibles are estimated to have a useful life consistent with the useful life of the related tower assets, which is typically 15 years. For all intangible assets, amortization is provided using the straight-line method over the estimated useful lives as the benefit associated with these intangible assets is anticipated to be derived evenly over the life of the asset.

Impairment of Long-Lived Assets

The Company evaluates its individual long-lived and related assets with finite lives for indicators of impairment to determine when an impairment analysis should be performed. The Company evaluates its tower assets and Current contract intangibles at the tower level, which is the lowest level for which identifiable cash flows exists. The Company evaluates its Network location intangibles for impairment at the tower leasing business level whenever indicators of impairment are present. The Company has established a policy to at least annually evaluate its tower assets and Current contract intangibles for impairment.

The Company records an impairment charge when the Company believes an investment in towers or related assets has been impaired, such that future undiscounted cash flows would not recover the then current carrying value of the investment in the tower and related intangible. If the future undiscounted cash flows are lower than the carrying value of the investment in the tower and related intangible, the Company calculates future discounted cash flows and compares those amounts to the carrying value. The Company records an impairment charge for any amounts lower than the carrying value. Estimates and assumptions inherent in the impairment evaluation include, but are not limited to, general market and economic conditions, historical operating results, geographic location, lease-up potential and expected timing of lease-up. In addition, the Company makes certain assumptions in determining an asset’s fair value for the purpose of calculating the amount of an impairment charge.

The Company recognized impairment charges of $36.7 million, $30.2 million, and $94.8 million for the years ended December 31, 2017, 2016 and 2015, respectively. Refer to Note 3 for further detail of these amounts.

Fair Value Measurements

The Company determines the fair market values of its financial instruments based on the fair value hierarchy, which requires an entity to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. The following three levels of inputs may be used to measure fair value:




Level 1	Quoted prices in active markets for identical assets or liabilities that the Company has the ability to access at the measurement date.

Level 2	Observable inputs other than Level 1 prices, such as quoted prices for similar assets or liabilities; quoted prices in markets that are not active; or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities.

Level 3	Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities.

Revenue Recognition

Revenue from site leasing is recorded monthly and recognized on a straight-line basis over the current term of the related lease agreements, which are generally five to ten years. Receivables recorded related to the straight-lining of site leases are reflected in other assets on the Consolidated Balance Sheets. Rental amounts received in advance are recorded as deferred revenue on the Consolidated Balance Sheets.

Site development projects in which the Company performs consulting services include contracts on a time and materials basis or a fixed price basis. Time and materials based contracts are billed at contractual rates and revenue is recognized as the services are rendered. For those site development contracts in which the Company performs work on a fixed price basis, site development billing (and revenue recognition) is based on the completion of agreed upon phases of the project on a per site basis. Upon the completion of each phase on a per site basis, the Company recognizes the revenue related to that phase. Site development projects generally take from 3 to 12 months to complete. Amounts billed in advance (collected or uncollected) are recorded as deferred revenue on the Company’s Consolidated Balance Sheets.

Revenue from construction projects is recognized on the percentage-of-completion method of accounting, determined by the percentage of cost incurred to date compared to management’s estimated total cost for each contract. This method is used because management considers total cost to be the best available measure of progress on the contracts. These amounts are based on estimates, and the uncertainty inherent in the estimates initially is reduced as work on the contracts nears completion. The asset “costs and estimated earnings in excess of billings on uncompleted contracts” represents costs incurred and revenues recognized in excess of amounts billed. The liability “billings in excess of costs and estimated earnings on uncompleted contracts,” included within other current liabilities on the Company’s Consolidated Balance Sheets, represents billings in excess of costs incurred and revenues recognized. Provisions for estimated losses on uncompleted contracts are made in the period in which such losses are determined to be probable.

Allowance for Doubtful Accounts

The Company performs periodic credit evaluations of its customers. The Company monitors collections and payments from its customers and maintains a provision for estimated credit losses based upon historical experience, specific customer collection issues identified, and past due balances as determined based on contractual terms. Interest is charged on outstanding receivables from customers on a case by case basis in accordance with the terms of the respective contracts or agreements with those customers. Amounts determined to be uncollectible are written off against the allowance for doubtful accounts in the period in which uncollectibility is determined to be probable.

The following is a rollforward of the allowance for doubtful accounts:



	For the year ended December 31,
	2017		2016		2015

		(in thousands)
Beginning balance	$	24,518	$	1,681	$	889
Provision for doubtful accounts		2,909		22,516		896
Write-offs, net of recoveries		(647)		(614)		(72)
Currency translation adjustment		(299)		935		(32)
Ending balance	$	26,481	$	24,518	$	1,681

On June 20, 2016, Oi, S.A. (“Oi”), the Company’s largest customer in Brazil, filed a petition for judicial reorganization in Brazil. Prior to the filing of the reorganization petition, Oi was current in all payment obligations to the Company. These obligations related to periods ending on or before April 30, 2016. As a result of the relief provisions available in a judicial reorganization proceeding, obligations of Oi to the Company arising from the periods from May 1, 2016 to June 20, 2016 remain unpaid. Due to the uncertainty surrounding the recoverability of amounts owed by Oi relating to services provided prior to the date of Oi’s petition, the Company has recorded a $16.5 million bad debt provision (the “Oi reserve”) which covers amounts owed or potentially owed by Oi as of the filing date. Under Brazilian law governing judicial reorganizations, the contracts governing post-petition obligations such as tower rents remain unchanged, and debtors do not have the ability to reject or terminate the contracts other than pursuant to their original terms. Since the filing, the Company has received all rental payments due in connection with obligations of Oi accruing post-petition. The Oi reserve was recorded in Selling, general, and administrative expense on the consolidated statement of operations for the year ended December 31, 2016. On January 8, 2018, Oi’s reorganization plan was approved by the Brazilian courts and Oi is expected to fully resolve all its pre-petition obligations in accordance with the terms of the plan.

Cost of Revenue

Cost of site leasing revenue includes ground lease rent, property taxes, amortization of deferred lease costs, maintenance and other tower operating expenses. All ground lease rental obligations due to be paid out over the lease term, including fixed escalations, are recorded on a straight-line basis over the minimum lease term. Liabilities recorded related to the straight-lining of ground leases are reflected in other long-term liabilities on the Consolidated Balance Sheets. Cost of site development revenue includes the cost of materials, salaries and labor costs, including payroll taxes, subcontract labor, vehicle expense and other costs directly and indirectly related to the projects. All costs related to site development projects are recognized as incurred.

Income Taxes

The Company recognizes deferred tax assets and liabilities for the estimated future tax consequences attributable to differences between the financial reporting and tax bases of existing assets and liabilities. Deferred tax assets and liabilities are measured using tax rates in effect for the year in which the temporary differences are expected to reverse. A valuation allowance is recorded to reduce the carrying amounts of deferred tax assets if it is "more-likely-than-not" that those assets will not be realized. The Company considers many factors when assessing the likelihood of future realization, including the Company's recent cumulative earnings experience by taxing jurisdiction, expectations of future taxable income, prudent and feasible tax planning strategies that are available, the carryforward periods available to the Company for tax reporting purposes and other relevant factors.

The Company began operating as a REIT for federal income tax purposes effective January 1, 2016. As a REIT, the Company generally is not subject to corporate level federal income tax on taxable income it distributes to its stockholders as long as it meets the organizational and operational requirements under the REIT rules. However, certain subsidiaries have made an election with the IRS to be treated as a taxable REIT subsidiary (“TRS”) in conjunction with the Company's REIT election. The TRS elections permit SBA to engage in certain business activities in which the REIT may not engage directly, so long as these activities are conducted in entities that elect to be treated as TRSs under the Internal Revenue Code. A TRS is subject to federal and state income taxes on the income from these activities. Additionally, the Company has included in TRSs the Company’s tower operations in most foreign jurisdictions; however, the REIT holds selected tower assets in Puerto Rico and USVI. Those operations will continue to be subject to foreign taxes in the jurisdiction in which such assets and operations are located regardless of whether they are included in a TRS.

The Company will continue to file separate federal tax returns for the REIT and TRS for the year ended December 31, 2017. The REIT had taxable income and utilized net operating losses (“NOLs”) to offset its distribution requirement. The TRS generated a NOL which will be carried forward to use in future years. The NOLs generated by the TRS are fully reserved by a valuation allowance.

The Company records a liability for unrecognized tax benefits resulting from uncertain tax positions taken or expected to be taken in a tax return. The Company has not identified any tax exposures that require a reserve. To the extent that the Company records unrecognized tax exposures, any related interest and penalties will be recognized as interest expense in the Company’s Consolidated Statements of Operations.

Stock-Based Compensation

The Company measures and recognizes compensation expense for all share-based payment awards made to employees and directors, including stock options, restricted stock units and employee stock purchases under employee stock purchase plans. The Company records compensation expense, for stock options and restricted stock units on a straight-line basis over the vesting period. Compensation expense for employee stock options is based on the estimated fair value of the options on the date of the grant using the Black-Scholes option-pricing model. Compensation expense for restricted stock units is based on the fair market value of the units awarded at the date of the grant.

Asset Retirement Obligations

The Company has entered into ground leases for the land underlying the majority of the Company’s towers. A majority of these leases require the Company to restore land interests to their original condition upon termination of the ground lease.

The Company recognizes asset retirement obligations in the period in which they are incurred, if a reasonable estimate of a fair value can be made, and accretes such liability through the obligation’s estimated settlement date. The associated asset retirement costs are capitalized as part of the carrying amount of the related tower fixed assets, and over time, the liability is accreted to its present value each period and the capitalized cost is depreciated over the estimated useful life of the tower.

The asset retirement obligation is included in other long-term liabilities on the Consolidated Balance Sheets. Upon settlement of the obligations, any difference between the cost to retire an asset and the recorded liability is recorded in the Consolidated Statements of Operations. In determining the measurement of the asset retirement obligations, the Company considered the nature and scope of the contractual restoration obligations contained in the Company’s ground leases, the historical retirement experience as an indicator of future restoration probabilities, intent in renewing existing ground leases through lease termination dates, current and future value and timing of estimated restoration costs and the credit adjusted risk-free rate used to discount future obligations.

The following summarizes the activity of the asset retirement obligation liability:



	For the year ended December 31,
	2017		2016		2015

	(in thousands)
Beginning balance	$	6,442	$	6,309	$	5,856
Additions		818		1,091		781
Currency translation adjustment		(10)		121		(57)
Accretion expense		665		318		373
Removal		(280)		(290)		(50)
Revision in estimates		(421)		(1,107)		(594)
Ending balance	$	7,214	$	6,442	$	6,309

Comprehensive Income (Loss)

Comprehensive income (loss) is defined as the change in equity (net assets) of a business enterprise during a period from transactions and other events and circumstances from non-owner sources, and is comprised of net income (loss) and other foreign currency adjustments.

Foreign Currency Translation

All assets and liabilities of foreign subsidiaries that do not utilize the U.S. dollar as its functional currency are translated at period-end rates of exchange, while revenues and expenses are translated at monthly average rates of exchange prevailing during the year. Unrealized remeasurement gains and losses are reported as foreign currency translation adjustments through Accumulated Other Comprehensive Loss in the accompanying Consolidated Statement of Shareholders’ Deficit.

For foreign subsidiaries where the U.S. dollar is the functional currency, monetary assets and liabilities of such subsidiaries, which are not denominated in U.S. dollars, are remeasured at exchange rates in effect at the balance sheet date, and revenues and expenses are remeasured at monthly average rates prevailing during the year. Unrealized translation gains and losses are reported as other income (expense), net in the Consolidated Statement of Operations.

Acquisitions

In January 2017, the FASB issued ASU 2017-01, Clarifying the Definition of a Business. ASU 2017-01 provides revised guidance to determine when an acquisition meets the definition of a business or when the acquisition should be accounted for as an asset acquisition. The Company adopted this standard effective January 1, 2017 and all changes are being accounted for prospectively. The adoption of ASU 2017-01 did not have a material impact on the Company’s unaudited consolidated financial statements and related disclosures.

Under the new standard, the Company’s acquisitions will generally qualify for asset acquisition treatment under ASC 360, Property, Plant, and Equipment, rather than business combination treatment under ASC 805 Business Combinations. For acquisitions which qualify as asset acquisitions, the aggregate purchase price is allocated on a relative fair value basis to towers and related intangible assets. For asset acquisitions, external, direct transaction costs will be capitalized as a component of the cost of the asset acquired. The Company will continue to expense internal acquisition costs as incurred.

The Company accounts for business combinations under the acquisition method of accounting. The assets and liabilities acquired are recorded at fair market value at the date of each acquisition and the results of operations of the acquired assets are included with those from the dates of the respective acquisitions. The Company continues to evaluate all acquisitions for a period not to exceed one year after the applicable closing date of each transaction to determine whether any additional adjustments are needed to the allocation of the purchase price paid for the assets acquired and liabilities assumed as a result of information available at the acquisition date.

The fair values of net assets acquired are based on management’s estimates and assumptions, as well as other information compiled by management, including valuations that utilize customary valuation procedures and techniques. The fair value estimates are based on available historical information and on future expectations and assumptions deemed reasonable by management at the time. If the actual results differ from the estimates and judgments used in these fair values, the amounts recorded in the consolidated financial statements could be subject to a possible impairment of the intangible assets, or require acceleration of the amortization expense of intangible assets in subsequent periods.

In connection with certain acquisitions, the Company may agree to pay contingent consideration (or earnouts) in cash or stock if the communication sites or businesses that are acquired meet or exceed certain performance targets over a period of one to three years after they have been acquired. The Company accrues for contingent consideration in connection with business combinations at fair value as of the date of the acquisition. All subsequent changes in fair value of contingent consideration payable in cash are recorded through Consolidated Statements of Operations. Contingent consideration in connection with asset acquisitions will be recognized at the time when the contingency is resolved or becomes payable and will increase the cost basis of the assets acquired.

Intercompany Loans Subject to Remeasurement

The Company has two wholly owned subsidiaries, Brazil Shareholder I, LLC, a Florida limited liability company, and SBA Torres Brasil, Limitada, a limitada existing under the laws of the Republic of Brazil, which have entered into intercompany loan agreements pursuant to which the entities may from time to time agree to lend/borrow amounts under the terms of each agreement. The first agreement entered into in November 2014 was for $750.0 million and was created to fund the acquisition of 1,641 towers in Brazil. The second agreement entered into in December 2017 was for $500.0 million and was created to fund the acquisition of 941 towers in Brazil.

In accordance with ASC 830, the Company remeasures foreign denominated intercompany loans with the corresponding change in the balance being recorded in Other income (expense), net in the Consolidated Statements of Operations as settlement is anticipated or planned in the foreseeable future. For the years ended December 31, 2017, 2016, and 2015, the Company recorded a $8.8 million loss, a $90.0 million gain, and a $178.9 million loss, respectively, on the remeasurement of intercompany loans due to changes in foreign exchange rates. As of December 31, 2017, the aggregate amount outstanding under the two intercompany loan agreements with the Company’s Brazilian subsidiary was $560.9 million.

Recent Accounting Pronouncements Not Yet Adopted

In May 2014, the FASB released an updated standard regarding the recognition of revenue from contracts with customers, exclusive of those contracts within lease accounting. The core principle of the standard is that an entity should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. To achieve that core principle, an entity should apply the following steps: (1) identify the contracts with the customer; (2) identify the performance obligations in the contract; (3) determine the contract price; (4) allocate the transaction price to the performance obligations in the contract; and (5) recognize revenue when (or as) the entity satisfies a performance obligation. This standard is effective for the Company in the first quarter of 2018. This standard is required to be applied retrospectively to each prior reporting period presented (full retrospective) or with the cumulative effect being recognized at the date of initial application (modified retrospective). The Company will apply the modified retrospective transition method upon adoption. The Company has finalized its review of the impact of adopting this new guidance, and there will not be any material changes to the timing or measurement of revenue recognition. The standard only affects the Company’s site development segment, which represents approximately 6% of the Company’s total revenues.

In February 2016, the FASB issued ASU 2016-02, Leases. The standard requires lessees to recognize a right-of-use asset and a lease liability, initially measured at the present value of the lease payments for all leases with a term greater than 12 months. The accounting for lessors remains largely unchanged from existing guidance. This standard is effective for annual and interim periods beginning after December 15, 2018. Early adoption is permitted; however, the Company does not currently plan to early adopt. The Company has established a cross functional project plan and is assessing the impact of the standard on its consolidated financial statements. The Company expects this guidance to have a material impact on its consolidated balance sheet due to the recognition of right-of-use assets and lease liabilities for its ground leases. The Company does not expect adoption to have a significant impact on its lease classification or to have a material impact on its consolidated statement of operations.