Basis of Presentation, Business and Summary of Significant Accounting Policies | 1. Basis of Presentation, Business and Summary of Significant Accounting Policies The terms "we", "our", "us", "Successor" or the "Company" refer to GMS Inc. and its subsidiaries. When such terms are used in this manner throughout the notes to the consolidated financial statements, they are in reference only to the corporation, GMS Inc. and its subsidiaries, and are not used in reference to the Board of Directors, corporate officers, management, or any individual employee or group of employees. On April 1, 2014, GYP Holdings I Corp., or the Successor, acquired, through its wholly-owned entities, GYP Holdings II Corp. and GYP Holdings III Corp., all of the capital stock of Gypsum Management and Supply, Inc. (the "Predecessor"). Successor is majority owned by certain affiliates of AEA Investors LP, or "AEA", and certain of our other stockholders. We refer to this acquisition as the "Acquisition" and April 1, 2014 as the "Acquisition Date". We were previously known as GYP Holdings I Corp. and changed our name to GMS Inc. on July 6, 2015. We have no independent operations and our only asset is our investment in the Predecessor. Revision of Previously Issued Statements of Cash Flows During the preparation of the Annual Report on Form 10-K for the year ended April 30, 2017, the Company determined that cash flows related to payments of working capital settlements were inappropriately classified as financing activities in the Consolidated Statements of Cash Flows for the fiscal years ended April 30, 2016 and 2015. This resulted in understatements of "Cash used in investing activities" (specifically the line item "Acquisitions of businesses, net of cash acquired") and "Cash provided by financing activities" (specifically the line item "Cash paid for contingent consideration") of $6,598 and $1,001 in the Consolidated Statements of Cash Flows for the years ended April 30, 2016 and 2015, respectively. The Company assessed the materiality of the misstatement in accordance with SEC Staff Accounting Bulletin No. 99, Materiality, and concluded that this misstatement was not material to the Company's previously issued financial statements and that amendments of previously filed reports were therefore not required. However, the Company has elected to revise the previously reported amounts in the 2016 and 2015 Consolidated Statements of Cash Flows in this Form 10-K filing. Disclosure of the revised amounts for applicable fiscal 2017 interim periods will also be reflected in future filings containing such interim periods. The effect of this revision on the line items within the Company's Consolidated Statement of Cash Flows for the year ended April 30, 2016 was as follows: Year Ended April 30, 2016 As previously Adjustment As revised Cash flows from investing activities: Acquisition of businesses, net of cash acquired $ ) $ ) $ ) Cash used in investing activities $ ) $ ) $ ) Cash flows from financing activities: Cash paid for contingent consideration $ ) $ $ — Cash flows from financing activities $ $ $ The effect of this revision on the line items within the Company's Consolidated Statement of Cash Flows for the year ended April 30, 2015 was as follows: Year Ended April 30, 2015 As previously Adjustment As revised Cash flows from investing activities: Acquisition of businesses, net of cash acquired ) $ ) ) Cash used in investing activities $ ) $ ) $ ) Cash flows from financing activities: Cash paid for contingent consideration $ ) $ $ — Cash flows from financing activities $ $ $ Business Founded in 1971, we are a distributor of specialty building products including wallboard, suspended ceiling systems, or ceilings, steel framing and other complementary specialty building products. We purchase products from a large number of manufacturers and then distribute these goods to a customer base consisting of wallboard and ceilings contractors and homebuilders, and to a lesser extent, general contractors and individuals. We have created a national footprint with more than 205 branches across 42 states. Initial and Secondary Public Offerings On May 13, 2016, we amended and restated our certificate of incorporation to increase our authorized share count to 550,000,000 shares of stock, including 500,000,000 shares of common stock and 50,000,000 shares of preferred stock, each with a par value $0.01 per share and to split our common stock 10.158-for-1. Unless otherwise noted herein, historic share data has been adjusted to give effect to the stock split. On June 1, 2016, we completed our initial public offering, or IPO, of 8,050,000 shares of common stock at a price of $21.00 per share, including 1,050,000 shares of common stock that were issued as a result of the exercise in full by the underwriters of an option to purchase additional shares to cover over-allotments. Our common stock began trading on the New York Stock Exchange, or the NYSE, on May 26, 2016 under the ticker symbol "GMS". After underwriting discounts and commissions, but before expenses, we received net proceeds from the IPO of approximately $156.9 million. We used these proceeds together with cash on hand to repay $160.0 million principal amount of our term loan debt outstanding under our senior secured second lien term loan facility, or the Second Lien Facility, which was a payment in full of the entire loan balance due under the Second Lien Facility. On February 22, 2017, certain stockholders of the Company completed a secondary public offering of 7,992,500 shares of the Company's common stock at a price to the public of $29.25 per share, including 1,042,500 shares of common stock that were issued as a result of the exercise in full by the underwriters of an option to purchase additional shares that was granted by the selling stockholders. The common stock offered in the secondary offering included 3,549,302 shares offered by affiliates of AEA. Principles of Consolidation The Consolidated Financial Statements present the results of operations, financial position and cash flows of the Company and its subsidiaries. All material intercompany balances and transactions have been eliminated in consolidation. Results of operations of businesses acquired are included from their respective dates of acquisition. Use of Estimates The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America ("GAAP") requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates. Revenue Recognition We recognize revenue at the point of sale or upon delivery to the customer's site when the following four basic criteria are met: • persuasive evidence of an arrangement exists; • delivery has occurred or services have been rendered; • the price to the buyer is fixed or determinable; and • collectability is reasonably assured. Revenue, net of estimated returns and allowances, is recognized when sales transactions occur and title is passed and the related product is delivered. Revenue includes any applicable shipping and handling costs invoiced to the customer. The expense related to such costs is included in "Selling, general and administrative" expenses in the accompanying Consolidated Statements of Operations and Comprehensive Income (Loss). Cost of Sales "Cost of sales" reflects the direct cost of goods purchased from third parties, rebates earned from vendors, adjustments for inventory reserves, and the cost of inbound freight. Operating Expenses "Operating expenses" include "Selling, general and administrative" expenses and "Depreciation and amortization". "Selling, general and administrative" expenses include expenses related to the delivery and warehousing of our products, as well as employee compensation and benefits expenses for employees in our branches and yard support center, as well as other administrative expenses, such as legal, accounting, and IT costs. Included in "Selling, general and administrative" expenses are delivery expenses of $205,019, $159,098 and $128,381 for 2017, 2016 and 2015, respectively. "Depreciation and amortization" expenses include depreciation expense on our property and equipment as well as amortization expense on our finite lived intangible assets. Cash and Cash Equivalents The Company considers all highly liquid investments with a maturity of three months or less when purchased to be cash equivalents. The carrying values of cash and cash equivalents approximate their fair values due to the short-term nature of these investments. Trade Accounts Receivable Accounts receivable are evaluated for collectability based on numerous factors including the age of the receivable and the history of writeoffs. We maintain allowances for doubtful accounts for estimated losses due to the failure of our customers to make required payments, as well as allowances for sales returns and cash discounts. Our estimate of the allowance for doubtful accounts is based on an assessment of individual past due accounts, historical write-off experience, accounts receivable aging and the current economic trends. Account balances are written off when the potential for recovery is considered remote. Our estimates for cash discounts and returns are based on an analysis of historical write-offs. Based on our evaluation, we have established estimated reserves for uncollectible accounts, returns and cash discounts of $9,851 and $8,607 as of April 30, 2017 and 2016, respectively. Inventories "Inventories, net" consist of materials purchased for resale and include wallboard, ceilings, steel framing and other specialty building products. The cost of our inventories is determined by the moving average cost method, which approximates the first-in, first-out approach. We monitor our inventory levels by branch and record provisions for excess inventories based on slower moving inventory. We define excess inventory as the amount of inventory on hand in excess of the historical usage, excluding items purchased in the last 12 months. We then review our most recent history of sales and adjustments of such excess inventory and apply our judgment as to forecasted demand and other factors, including liquidation value, to determine the required adjustments to net realizable value. In addition, at the end of each year, we evaluate our inventory at each branch and write off and dispose of obsolete products. Our inventories are generally not susceptible to technological obsolescence. Vendor Rebates Typical arrangements with our vendors provide for us to receive a rebate of a specified amount after we achieve any of a number of measures generally related to the volume of our purchases over a period of time. We record these rebates to effectively reduce our cost of sales in the period in which we sell the product. Throughout the year, we estimate the amount of rebates receivable for the periodic programs based upon the expected level of purchases. We accrue for the receipt of vendor rebates based on purchases and also reduce inventory to reflect the deferral of cost of sales. Property and Equipment "Property and equipment, net" is recorded at cost. Buildings, furniture, fixtures and equipment are depreciated using the straight-line method over the estimated useful lives of the assets. Expenditures for improvements and betterments, which extend the useful lives of assets, are capitalized while maintenance and repairs are charged to expense as incurred. Property and equipment obtained through acquisition are stated at estimated fair value as of the acquisition date, and are depreciated over their estimated remaining useful lives. Gains and losses related to the sale of property and equipment are recorded as "Selling, general and administrative" expenses. Property and equipment is depreciated and amortized using the following estimated useful lives: Life (years) Buildings 25 - 39 Leasehold improvements 1 - 15 Furniture, fixtures, and automobiles 3 - 5 Warehouse and delivery equipment 4 - 5 Assets held under capital lease 2 - 11 Leased property and equipment meeting capital lease criteria are capitalized at the lower of the present value of the related lease payments or the fair value of the leased asset at the inception of the lease. Leasehold improvements and assets under capital leases are amortized using the straight-line method over the shorter of their estimated useful lives or the initial term of the related lease. Long-lived assets to be held and used are reviewed for impairment whenever facts and circumstances indicate that the carrying amount of an asset may not be recoverable. For impairment testing of long-lived assets, we identify asset groups at the lowest level for which identifiable cash flows are largely independent of the cash flows for other groups of assets and liabilities. Recoverability of assets to be held and used is measured by a comparison of the carrying amount of an asset to the estimated undiscounted future cash flows expected to be generated by the assets. If the carrying amount of an asset exceeds its estimated future cash flows, an impairment charge is recognized in an amount by which the carrying amount of the asset exceeds the estimated fair value of the asset. Assets are classified as held for sale if the Company commits to a plan to sell the asset within one year and actively markets the asset in its current condition for a price that is reasonable in comparison to its estimated fair value. Assets held for sale are stated at lower of depreciated cost or estimated fair value less expected disposition costs and are recorded within "Prepaid expenses and other current assets". During 2017, 2016 and 2015, the Company recognized impairment losses of $485, $373 and $173, respectively, related to land and buildings held for sale. These losses were included in "Selling, general and administrative" expenses in the Consolidated Statements of Operations and Comprehensive Income (Loss). Goodwill Goodwill represents the excess of purchase price over fair value of net assets acquired. We do not amortize goodwill, but do assess goodwill for impairment in the fourth quarter of each fiscal year or whenever events or circumstances indicate that it is "more likely than not" that the fair value of a reporting unit had dropped below its carrying value. For the fiscal 2017, 2016 and 2015 annual impairment tests, the fair values of our identified reporting units were estimated using a discounted cash flow ("DCF") analysis, a market comparable method, and a market transaction approach. The weighting of each approach used was 50%, 40%, and 10% for the DCF approach, the market comparable approach and the transaction approach respectively. There were no goodwill impairment charges recorded. See Note 5, "Goodwill and Intangible Assets," for a complete description of the Company's goodwill. Intangible Assets The Company typically uses an income method to estimate the fair value of "Intangible assets", which is based on forecasts of the expected future cash flows attributable to the respective assets. Significant estimates and assumptions inherent in the valuations reflect a consideration of other marketplace participants and include the amount and timing of future cash flows (including expected growth rates and profitability), the underlying product, the economic barriers to entry and the discount rate applied to the cash flows. Unanticipated market or macroeconomic events and circumstances may occur that could affect the accuracy or validity of the estimates and assumptions. Determining the useful life of an intangible asset also requires judgment. Certain intangibles are expected to have indefinite lives based on their history and the Company's plans to continue to support and build the acquired brands. Other acquired intangible assets such as customer relationships and other brand or trade names are expected to have definite useful lives. All of the Company's customer-related intangibles are expected to have definite useful lives. The costs of definite lived intangibles are amortized over their estimated lives. Deferred Financing Costs The Company capitalizes debt issuance costs and amortizes them over the term of the related debt. The Company uses the straight-line method to amortize debt issuance costs related to the ABL Facility (as defined below), while the effective interest method is used to amortize debt issuance costs related to the Term Loan Facilities (as defined below). Amortization of debt issuance costs is recorded in "Interest expense" within the Consolidated Statements of Operations and Comprehensive Income (Loss). Lender and third party deferred financing costs are reported as a reduction of the Term Loan Facilities of $5,712 and $11,147 as of April 30, 2017 and 2016, respectively, in the Consolidated Balance Sheets. Lender and third party deferred financing costs related to the ABL Facility are reported as an asset of $2,950 and $2,544 as of April 30, 2017 and 2016, respectively, in the Consolidated Balance Sheets. Amortization of the Term Loan Facilities and ABL Facility costs were $2,247, $2,961 and $2,907 in 2017, 2016 and 2015, respectively. In addition, in connection with refinancing of the ABL and term loans, $7,103 was written off in 2017. Derivative Instruments The Derivative financial instruments are recognized as either assets or liabilities in the Consolidated Balance Sheets and measured at fair value. Derivatives that do not qualify as a hedge must be adjusted to fair value in earnings. If the derivative does qualify as a hedge, under the Financial Accounting Standards Board ("FASB") issued Accounting Standards Codification ("ASC") Topic 815, " Derivatives and hedging ", changes in the fair value will either be offset against the change in fair value of the hedged assets, liabilities or firm commitments or recognized in accumulated other comprehensive income until the hedged item is recognized in earnings. The ineffective portion of a hedge's change in fair value is immediately recognized in earnings. We enter into interest rate derivative agreements, commonly referred to as caps or swaps, with the objective of minimizing the risks and costs associated with financing activities, as well as to maintain an appropriate mix of fixed-and floating-rate debt. These agreements are contracts to exchange variable-rate for fixed-interest rate payments over the life of the agreements. For derivative instruments designated as hedges per ASC 815, we record the effective portions of changes in their fair value, net of taxes, in "Comprehensive income (loss)" to the extent the derivative is considered perfectly effective in achieving offsetting changes in fair value or cash flows attributable to the risk being hedged, until the hedged item is recognized in earnings (commonly referred to as the "hedge accounting" method). The effectiveness of the hedges is periodically assessed by management during the lives of the hedges by: 1) comparing the current terms of the hedges with the related hedged debt to assure they continue to coincide and 2) evaluating the ability of the counterparties to the hedges to honor their obligations under the hedges. Any ineffective portions of the hedges are recognized in earnings through interest expense, financing costs and other expenses. During the year ended April 30, 2015, we elected to designate a derivative instrument as a cash flow hedge in accordance with ASC 815. This instrument is an interest rate cap on quarterly resetting 3-month LIBOR, based on a strike rate of 2.0% and payable quarterly. This instrument effectively caps the interest rate at 5.75% on an initial notional amount of $275,000 of our variable rate debt obligation under the First Lien Facility, or any replacement facility with similar terms. The interest rate cap was purchased for $4,638 on October 31, 2014, designated as a hedge on January 31, 2015, and expires on October 31, 2018. This derivative instrument is recorded in the Consolidated Balance Sheet as of April 30, 2017 and 2016, respectively, as an asset at its fair value of $88 and $271 within "Other assets". The valuation of this instrument was determined using widely accepted valuation techniques including a discounted cash flow analysis on the expected cash flows of the derivative. This analysis reflected the contractual terms of the derivatives, including the period to maturity, and used observable market-based inputs, including interest rate curves and implied volatilities. The decrease in fair value of the instrument from the purchase date to the date of hedge designation was $2,494 and is reflected in earnings through "Change in fair value of financial instruments" on the Consolidated Statements of Operations and Comprehensive Income (Loss) for the year ended April 30, 2015. The increase in fair value from the effective hedge date to the year ended April 30, 2015 was $10 and was recorded in "(Decrease) increase in fair value of financial instruments, net of tax" in "Comprehensive income (loss)". The decrease in fair value for the year ended April 30, 2016 was $1,158 and was recorded in "(Decrease) increase in fair value of financial instruments, net of tax" in "Comprehensive income (loss)". The increase in fair value for the year ended April 30, 2017 was $264 and was recorded in "(Decrease) increase in fair value of financial instruments, net of tax" in "Comprehensive income (loss)". The Company believes there have been no material changes in the creditworthiness of the counterparty to this cap agreement and believes the risk of nonperformance by such party is minimal. See Note 16, "Accumulated Other Comprehensive (Loss) Income." We consider the interest rate cap to be a Level 2 fair value measurement for which market-based pricing inputs are observable. Generally, we obtain our Level 2 pricing inputs from our counterparties. Substantially all of these assumptions are observable in the marketplace throughout the full term of the instrument, which can be derived from observable data or are supported by observable levels at which transactions are executed in the marketplace. For derivatives that do not qualify or are not designated as hedging instruments for accounting purposes, changes in fair value are recorded in current period earnings (commonly referred to as the "mark-to-market" method). We did not have any derivatives that did not qualify or were not designated as hedging instruments for accounting purposes, during the years ended April 30, 2017, 2016 and 2015, other than as noted above. Insurance Liabilities The Company is self-insured for certain losses related to medical claims. The Company has deductible-based insurance policies for certain losses related to general liability, workers' compensation and automobile. The deductible amount is $250, $500 and $1,000 for general liability, workers' compensation and automobile, respectively. The Company has stop-loss coverage to limit the exposure arising from claims. The coverage consists of a primary layer and an excess layer. The primary layer of coverage is from $500 to $2,000 and the excess layer covers claims from $2,000 to $100,000. The expected ultimate cost for claims incurred as of the balance sheet date is not discounted and is recognized as a liability. Insurance losses for claims filed and claims incurred but not reported are accrued based upon estimates of the aggregate liability for uninsured claims using loss development factors and actuarial assumptions followed in the insurance industry and historical loss development experience. At April 30, 2017 and 2016, the aggregate liabilities for medical self-insurance were $3,429 and $3,342, respectively, and are recorded in "Other accrued expenses and current liabilities" within the Consolidated Balance Sheets. At April 30, 2017 and 2016, reserves for general liability, automobile and workers' compensation totaled approximately $15,934 and $12,213 respectively, and are recorded in "Other accrued expenses and current liabilities" and "Other liabilities" in the Consolidated Balance Sheets. During the year ended April 30, 2016, an insured automobile claim related to prior years, subject to a $500 deductible, was paid by our insurance carrier in the amount of approximately $26,300. At April 30, 2017 and 2016, expected recoveries for general liability, automobile and workers' compensation totaled approximately $6,708 and $4,832, respectively and are recorded in "Prepaid expenses and other current assets" and "Other assets" in the Consolidated Balance Sheets. Income Taxes Income taxes are accounted for in accordance with ASC 740 " Income Taxes ," which requires the use of the asset and liability method. Deferred tax assets and liabilities are recognized based on the difference between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases. Inherent in the measurement of deferred balances are certain judgments and interpretations of existing tax law and published guidance as applicable to our operations. We evaluate our deferred tax assets to determine if valuation allowances are required. In assessing the realizability of deferred tax assets, we consider both positive and negative evidence in determining whether it is more likely than not that some portion or all of the deferred tax assets will not be realized. The primary negative evidence considered includes the cumulative operating losses generated in prior periods. The primary positive evidence considered includes the reversal of deferred tax liabilities related to depreciation and amortization that would occur within the same jurisdiction and during the carry-forward period necessary to absorb the federal and state net operating losses and other deferred tax assets. The reversal of such liabilities would utilize the federal and state net operating losses and other deferred tax assets. We record amounts for uncertain tax positions that management believes are supportable, but are potentially subject to successful challenge by the applicable taxing authority. Consequently, changes in our assumptions and judgments could materially affect amounts recognized related to income tax uncertainties and may affect our results of operations or financial position. We believe our assumptions for estimates are reasonable, although actual results may have a positive or negative material impact on the balances of such tax positions. Historically, the variation of estimates to actual results is not significant and material variation is not expected in the future. Credit and Economic Risk The Company's sources of liquidity have been and are expected to be cash from operating activities, available cash balances and the ABL Facility and the Term Loan Facilities. Financial instruments that potentially subject the Company to significant concentrations of credit risk consist principally of cash and cash equivalents and trade accounts and notes receivable. The Company assesses the credit standing of counterparties as considered necessary. The Company routinely assesses the financial strength of its customers and generally does not require collateral. Concentrations of credit risk with respect to trade accounts receivable are limited due to the large number of entities comprising the Company's customer base. The Company provides for doubtful accounts based on historical experience and when current conditions indicate that collection is doubtful. Accounts are written off when deemed uncollectible. In certain situations, the Company provides the customer with the right of product return; we have established a reserve for returns based on historic returns. The Company does not enter into financial instruments for trading or speculative purposes. The Company purchases a majority of its inventories from a select group of vendors. Without these vendors, the Company's ability to acquire inventory would be significantly impaired. Fair Value of Financial Instruments Fair value is the price that would be received to sell an asset or paid to transfer a liability in the principal or most advantageous market in an orderly transaction between market participants on the measurement date. The carrying values of cash and cash equivalents, receivables, accounts payable, other current liabilities and accrued interest approximates fair value due to its short-term nature. Based on borrowing rates available to the Company for loans with similar terms, the carrying values of the ABL Facility and other debt approximate fair value. Accounting guidance establishes a three-level hierarchy, which requires an entity to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. The valuation hierarchy is based upon the transparency of inputs to the valuation of an asset or liability on the measurement date. The three levels are defined as follows: Level 1 Inputs to the valuation methodology are quoted prices (unadjusted) for an identical asset or liability in an active market. Level 2 Inputs to the valuation methodology include quoted prices for a similar asset or liability in an active market or model-derived valuations in which all significant inputs are observable for substantially the full term of the asset or liability. The fair values of our liabilities for Stock Appreciation Rights, Liabilities to Non-controlling interest holders, and Deferred Compensation liabilities are based on Level 2 inputs. Level 3 Inputs to the valuation methodology are unobservable and significant to the fair value measurement of the asset or liability. Advertising Expense The cost of advertising is expensed as incurred and presented within "Selling, general and administrative" expenses in the Consolidated Statements of Operations and Comprehensive Income (Loss). The Company incurred approximately $2,270, $2,043, and $1,805 in advertising costs for the years ended April 30, 2017, 2016, and 2015, respectively. Equity-Based Compensation We account for stock options granted to employees and directors by recording compensation expense based on the award's fair value, estimated on the date of grant using the Black-Scholes option-pricing model. Equity-based compensation expense is recognized on a schedule that approximates the graded vesting of the awards. Determining the fair value of stock options under the Black-Scholes option-pricing model requires judgment, including estimating the fair value per share of our common stock, volatility, expected term of the awards, dividend yield and risk-free interest rate. The assumptions used in calculating the fair value of stock options represent our best estimates, based on management's judgment and subjective future expectations. These estimates involve inherent uncertainties. If any of the assumptions used in the model change significantly, share-based compensation recorded for future awards may differ materially from that recorded for awards granted previously. We estimate potential forfeitures of stock options and adjust share-based compensation expense accordingly. The estimate of forfeitures is adjusted over the requisite service period to the extent that actual forfeitures differ from prior estimates. We estimate forfeitures based upon our historical experience with employee turnover, and, on an annual basis, review the estimated forfeiture rate and make changes as factors affecting the forfeiture rate calculations and assumptions changes. We intend to use authorized and unissued shares to satisfy share award exercises, unless otherwise noted. Stock Appreciation Rights, Deferred Compensation and Liabilities to Noncontrolling Interest Holders Certain subsidiaries have equity based compensation agreements with the subsidiary's employees and minority shareholders. These agreements are stock appreciation rights, deferred compensation agreements and liabilities to noncontrolling interest holders. Since these agreements are typically settled in cash or notes, and do not meet the criteria established by ASC 718, " Compensation—Stock Compensation " to be accounted for in "Stockholders' equity", they are accounted for as liability awards. See Note 12, "Stock Appreciation Rights, Deferred Compensation and Redeemable Noncontrolling In |