GMS (GMS) 10-Q 4 Mar 21 2021 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Jan. 31, 2021	Feb. 28, 2021
Document and Entity Information
Document Type	10-Q
Document Quarterly Report	true
Document Transition Report	false
Document Period End Date	Jan. 31, 2021
Entity File Number	001-37784
Entity Registrant Name	GMS INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	46-2931287
Entity Address, Address Line One	100 Crescent Centre Parkway, Suite 800
Entity Address, City or Town	Tucker
Entity Address, State or Province	GA
Entity Address, Postal Zip Code	30084
City Area Code	800
Local Phone Number	392-4619
Title of 12(b) Security	Common Stock
Trading Symbol	GMS
Security Exchange Name	NYSE
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		42,846,578
Entity Central Index Key	0001600438
Current Fiscal Year End Date	--04-30
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q3
Amendment Flag	false

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Jan. 31, 2021	Apr. 30, 2020
Current assets:
Cash and cash equivalents	$ 150,573	$ 210,909
Trade accounts and notes receivable, net of allowances of $6,020 and $5,141, respectively	410,125	405,254
Inventories, net	327,725	299,815
Prepaid expenses and other current assets	17,684	14,972
Total current assets	906,107	930,950
Property and equipment, net of accumulated depreciation of $184,410 and $158,554, respectively	305,144	305,467
Operating lease right-of-use assets	119,434	115,257
Goodwill	562,204	553,073
Intangible assets, net	333,766	361,884
Deferred income taxes	13,488	8,904
Other assets	11,616	13,247
Total assets	2,251,759	2,288,782
Current liabilities:
Accounts payable	157,892	213,230
Accrued compensation and employee benefits	55,995	67,590
Other accrued expenses and current liabilities	81,913	63,812
Current portion of long-term debt	51,552	50,201
Current portion of operating lease liabilities	32,847	33,040
Total current liabilities	380,199	427,873
Non-current liabilities:
Long-term debt, less current portion	942,598	1,047,279
Long-term operating lease liabilities	92,109	89,605
Deferred income taxes, net	8,965	12,018
Other liabilities	66,874	78,026
Total liabilities	1,490,745	1,654,801
Commitments and contingencies
Stockholders' equity:
Common stock, par value $0.01 per share, 500,000 shares authorized; 42,854 and 42,554 shares issued and outstanding as of January 31, 2021 and April 30, 2020, respectively	428	426
Preferred stock, par value $0.01 per share, 50,000 shares authorized; 0 shares issued and outstanding as of January 31, 2021 and April 30, 2020
Additional paid-in capital	539,289	529,662
Retained earnings	240,789	168,975
Accumulated other comprehensive loss	(19,492)	(65,082)
Total stockholders' equity	761,014	633,981
Total liabilities and stockholders' equity	$ 2,251,759	$ 2,288,782

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) shares in Thousands, $ in Thousands	Jan. 31, 2021	Apr. 30, 2020
Condensed Consolidated Balance Sheets
Trade accounts and notes receivable, allowances (in dollars)	$ 6,020	$ 5,141
Property and equipment, accumulated depreciation (in dollars)	$ 184,410	$ 158,554
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized	500,000	500,000
Common stock, shares issued	42,854	42,554
Common stock, shares outstanding	42,854	42,554
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized	50,000	50,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations and Comprehensive Income - USD ($) shares in Thousands, $ in Thousands		3 Months Ended		9 Months Ended
		Jan. 31, 2021	Jan. 31, 2020	Jan. 31, 2021	Jan. 31, 2020
Condensed Consolidated Statements of Operations and Comprehensive Income
Net sales		$ 751,191	$ 761,352	$ 2,366,620	$ 2,470,457
Cost of sales (exclusive of depreciation and amortization shown separately below)		507,867	507,879	1,597,767	1,658,837
Gross profit		243,324	253,473	768,853	811,620
Operating expenses:
Selling, general and administrative		184,844	193,384	556,308	588,472
Depreciation and amortization		25,562	29,422	79,904	88,215
Total operating expenses		210,406	222,806	636,212	676,687
Operating income		32,918	30,667	132,641	134,933
Other (expense) income:
Interest expense		(13,454)	(16,474)	(41,060)	(52,310)
Gain on legal settlement		1,382		1,382
Write-off of debt discount and deferred financing fees					(707)
Other income (expense), net		989	(498)	2,441	1,254
Total other expense, net		(11,083)	(16,972)	(37,237)	(51,763)
Income before taxes		21,835	13,695	95,404	83,170
Provision for income taxes		5,709	2,816	23,590	18,333
Net income		$ 16,126	$ 10,879	$ 71,814	$ 64,837
Weighted average common shares outstanding:
Basic (in shares)		42,726	42,223	42,691	41,663
Diluted (in shares)		43,361	42,949	43,184	42,401
Net income per common share:
Basic (in dollars per share)	[1]	$ 0.38	$ 0.26	$ 1.68	$ 1.55
Diluted (in dollars per share)	[1]	$ 0.37	$ 0.25	$ 1.66	$ 1.52
Comprehensive income
Net income		$ 16,126	$ 10,879	$ 71,814	$ 64,837
Foreign currency translation income (loss)		20,373	(2,504)	39,813	8,947
Changes in other comprehensive income (loss), net of tax		1,974	(547)	5,777	(10,214)
Comprehensive income		$ 38,473	$ 7,828	$ 117,404	$ 63,570
[1]	See Note 15 for detailed calculations .

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($) shares in Thousands, $ in Thousands	Common Stock	Exchangeable Shares	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Loss	Total
Balance at Apr. 30, 2019	$ 404	$ 29,639	$ 480,113	$ 145,594	$ (26,574)	$ 629,176
Balance (in shares) at Apr. 30, 2019	40,375
Increase (Decrease) in Stockholders' Equity
Net income				24,820		24,820
Exercise of Exchangeable Shares	$ 11	(29,639)	29,628
Exercise of Exchangeable Shares (in shares)	1,129
Foreign currency translation adjustments					11,860	11,860
Other comprehensive loss, net of tax					(6,065)	(6,065)
Equity-based compensation			1,349			1,349
Exercise of stock options			133			133
Exercise of stock options (in shares)	9
Issuance of common stock pursuant to employee stock purchase plan	$ 1		1,021			1,022
Issuance of common stock pursuant to employee stock purchase plan (in shares)	76
Balance at Jul. 31, 2019	$ 416		512,244	170,414	(20,779)	662,295
Balance (in shares) at Jul. 31, 2019	41,589
Balance at Apr. 30, 2019	$ 404	$ 29,639	480,113	145,594	(26,574)	629,176
Balance (in shares) at Apr. 30, 2019	40,375
Increase (Decrease) in Stockholders' Equity
Net income						64,837
Foreign currency translation adjustments						8,947
Balance at Jan. 31, 2020	$ 423		524,313	210,431	(27,841)	707,326
Balance (in shares) at Jan. 31, 2020	42,310
Balance at Jul. 31, 2019	$ 416		512,244	170,414	(20,779)	662,295
Balance (in shares) at Jul. 31, 2019	41,589
Increase (Decrease) in Stockholders' Equity
Net income				29,138		29,138
Foreign currency translation adjustments					(409)	(409)
Other comprehensive loss, net of tax					(3,602)	(3,602)
Equity-based compensation			2,271			2,271
Exercise of stock options	$ 5		6,623			6,628
Exercise of stock options (in shares)	525
Vesting of restricted stock units	$ 1		(1)
Vesting of restricted stock units (in shares)	55
Tax withholding related to net share settlements of stock options/equity awards			(282)			(282)
Balance at Oct. 31, 2019	$ 422		520,855	199,552	(24,790)	696,039
Balance (in shares) at Oct. 31, 2019	42,169
Increase (Decrease) in Stockholders' Equity
Net income				10,879		10,879
Foreign currency translation adjustments					(2,504)	(2,504)
Other comprehensive loss, net of tax					(547)	(547)
Equity-based compensation			1,419			1,419
Exercise of stock options	$ 1		1,518			1,519
Exercise of stock options (in shares)	85
Vesting of restricted stock units (in shares)	17
Tax withholding related to net share settlements of stock options/equity awards			(250)			(250)
Issuance of common stock pursuant to employee stock purchase plan			771			771
Issuance of common stock pursuant to employee stock purchase plan (in shares)	39
Balance at Jan. 31, 2020	$ 423		524,313	210,431	(27,841)	707,326
Balance (in shares) at Jan. 31, 2020	42,310
Balance at Apr. 30, 2020	$ 426		529,662	168,975	(65,082)	$ 633,981
Balance (in shares) at Apr. 30, 2020	42,554					42,554
Increase (Decrease) in Stockholders' Equity
Net income				27,219		$ 27,219
Foreign currency translation adjustments					16,281	16,281
Other comprehensive loss, net of tax					959	959
Equity-based compensation			1,575			1,575
Exercise of stock options			691			691
Exercise of stock options (in shares)	54
Vesting of restricted stock units (in shares)	7
Tax withholding related to net share settlements of stock options/equity awards			(105)			(105)
Issuance of common stock pursuant to employee stock purchase plan	$ 1		1,269			1,270
Issuance of common stock pursuant to employee stock purchase plan (in shares)	58
Balance at Jul. 31, 2020	$ 427		533,092	196,194	(47,842)	681,871
Balance (in shares) at Jul. 31, 2020	42,673
Balance at Apr. 30, 2020	$ 426		529,662	168,975	(65,082)	$ 633,981
Balance (in shares) at Apr. 30, 2020	42,554					42,554
Increase (Decrease) in Stockholders' Equity
Net income						$ 71,814
Foreign currency translation adjustments						39,813
Balance at Jan. 31, 2021	$ 428		539,289	240,789	(19,492)	$ 761,014
Balance (in shares) at Jan. 31, 2021	42,854					42,854
Balance at Jul. 31, 2020	$ 427		533,092	196,194	(47,842)	$ 681,871
Balance (in shares) at Jul. 31, 2020	42,673
Increase (Decrease) in Stockholders' Equity
Net income				28,469		28,469
Foreign currency translation adjustments					3,159	3,159
Other comprehensive loss, net of tax					2,844	2,844
Repurchase and retirement of common stock	$ (1)		(1,221)			(1,222)
Repurchase and retirement of common stock (in shares)	(50)
Equity-based compensation			3,253			3,253
Exercise of stock options			172			172
Exercise of stock options (in shares)	5
Vesting of restricted stock units	$ 1		(1)
Vesting of restricted stock units (in shares)	62
Tax withholding related to net share settlements of stock options/equity awards			(649)			(649)
Balance at Oct. 31, 2020	$ 427		534,646	224,663	(41,839)	717,897
Balance (in shares) at Oct. 31, 2020	42,690
Increase (Decrease) in Stockholders' Equity
Net income				16,126		16,126
Foreign currency translation adjustments					20,373	20,373
Other comprehensive loss, net of tax					1,974	1,974
Repurchase and retirement of common stock			(778)			(778)
Repurchase and retirement of common stock (in shares)	(30)
Equity-based compensation			1,876			1,876
Exercise of stock options	$ 1		2,792			2,793
Exercise of stock options (in shares)	152
Vesting of restricted stock units (in shares)	4
Tax withholding related to net share settlements of stock options/equity awards			(53)			(53)
Issuance of common stock pursuant to employee stock purchase plan			806			806
Issuance of common stock pursuant to employee stock purchase plan (in shares)	38
Balance at Jan. 31, 2021	$ 428		$ 539,289	$ 240,789	$ (19,492)	$ 761,014
Balance (in shares) at Jan. 31, 2021	42,854					42,854

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Jan. 31, 2021	Jan. 31, 2020
Cash flows from operating activities:
Net income	$ 71,814	$ 64,837
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	79,904	88,215
Write-off and amortization of debt discount and debt issuance costs	2,257	2,964
Equity-based compensation	10,318	6,345
Gain on disposal and impairment of assets	(529)	(872)
Deferred income taxes	(9,645)	174
Other items, net	105	2,387
Changes in assets and liabilities net of effects of acquisitions:
Trade accounts and notes receivable	1,352	16,561
Inventories	(24,391)	317
Prepaid expenses and other assets	1,040	4,210
Accounts payable	(58,104)	(30,420)
Accrued compensation and employee benefits	(11,932)	(11,729)
Other accrued expenses and liabilities	6,307	(7,622)
Cash provided by operating activities	68,496	135,367
Cash flows from investing activities:
Purchases of property and equipment	(17,857)	(20,884)
Proceeds from sale of assets	1,233	1,299
Acquisition of businesses, net of cash acquired	(51)	(20,803)
Cash used in investing activities	(16,675)	(40,388)
Cash flows from financing activities:
Repayments on revolving credit facilities	(102,189)	(794,623)
Borrowings from revolving credit facilities	14,750	760,444
Payments of principal on long-term debt	(7,476)	(57,476)
Payments of principal on finance lease obligations	(22,662)	(17,971)
Repurchases of common stock	(2,000)
Debt issuance costs		(1,286)
Proceeds from exercises of stock options	3,656	8,280
Payments for taxes related to net share settlement of equity awards	(807)	(532)
Other financing activities	2,076	1,793
Cash used in financing activities	(114,652)	(101,371)
Effect of exchange rates on cash and cash equivalents	2,495	3
Decrease in cash and cash equivalents	(60,336)	(6,389)
Cash and cash equivalents, beginning of period	210,909	47,338
Cash and cash equivalents, end of period	150,573	40,949
Supplemental cash flow disclosures:
Cash paid for income taxes	31,942	30,199
Cash paid for interest	$ 38,114	$ 49,224

Business, Basis of Presentation

Business, Basis of Presentation and Summary of Significant Accounting Policies	9 Months Ended
	Jan. 31, 2021
Business, Basis of Presentation and Summary of Significant Accounting Policies
Business, Basis of Presentation and Summary of Significant Accounting Policies	1. Business, Basis of Presentation and Summary of Significant Accounting Policies ​ Business ​ Founded in 1971, GMS Inc. (“we,” “our,” “us,” or the “Company”), through its wholly-owned operating subsidiaries, is a distributor of specialty building products including wallboard, suspended ceilings systems, or ceilings, steel framing and other complementary building products. We purchase products from many 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 operate a network of more than 265 distribution centers across the United States and Canada. ​ Basis of Presentation ​ The condensed consolidated financial statements included in this Quarterly Report on Form 10-Q have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”) that permit reduced disclosure for interim periods. In the opinion of management, the accompanying unaudited condensed consolidated financial statements contain all normal and recurring adjustments necessary for a fair presentation of the results of operations, financial position and cash flows. All adjustments are of a normal recurring nature unless otherwise disclosed. The results of operations for interim periods are not necessarily indicative of results for any other interim period or the entire fiscal year. As a result, the unaudited condensed consolidated financial statements should be read in conjunction with our audited consolidated financial statements included in our Annual Report on Form 10-K for the fiscal year ended April 30, 2020. ​ Principles of Consolidation ​ The condensed consolidated financial statements present the results of operations, financial position, stockholders’ equity and cash flows of the Company and its subsidiaries. All material intercompany balances and transactions have been eliminated in consolidation. The 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 Generally Accepted Accounting Principles (“GAAP”) requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities as of 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. ​ Foreign Currency Translation ​ Assets and liabilities of the Company’s Canadian subsidiaries are translated at the exchange rate prevailing at the balance sheet date, while income and expenses are translated at average rates for the period. Translation gains and losses are reported as a separate component of stockholders’ equity and other comprehensive income. Gains and losses on foreign currency transactions are recognized in the Condensed Consolidated Statements of Operations and Comprehensive Income within other (expense) income, net. ​ Insurance Liabilities ​ The Company is self-insured for certain losses related to medical claims. The Company has stop-loss coverage to limit the exposure arising from medical claims. In addition, the Company has deductible-based insurance policies for certain losses related to general liability, workers’ compensation and automobile. The coverage consists of a deductible layer, a primary layer, a self-insured buffer layer, a lead umbrella layer and excess layers. The deductible amount per incident is $0.3 million, $0.5 million and $1.0 million for general liability, workers’ compensation and automobile, respectively. The primary layer of coverage is from $0.3 million, $0.5 million and $1.0 million for general liability, workers’ compensation, and automobile liability, respectively, to $5.0 million. The Company self-insures a buffer layer from $5.0 million to $10.0 million. The umbrella and excess layers cover claims from $10.0 million to $100.0 million. 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 historical loss development factors and actuarial assumptions followed in the insurance industry. The following table presents the Company’s aggregate liabilities for medical self-insurance, reserves for general liability, automobile and workers’ compensation and the expected recoveries for medical self-insurance, general liability, automobile and workers’ compensation. Liabilities for medical self-insurance are included in other accrued expenses and current liabilities. Reserves for general liability, automobile and workers’ compensation are included in other accrued expenses and current liabilities and other liabilities. Expected recoveries for insurance liabilities are included in prepaid expenses and other current assets and other assets in the Condensed Consolidated Balance Sheets. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ January 31, ​ April 30, ​ ​ 2021 2020 ​ ​ (in thousands) Medical self‑insurance ​ $ 3,778 ​ $ 3,770 General liability, automobile and workers’ compensation ​ ​ 20,520 ​ ​ 19,410 Expected recoveries for insurance liabilities ​ (7,813) ​ (6,037) ​ Income Taxes ​ The Company considers each interim period an integral part of the annual period and measures tax expense (benefit) using an estimated annual effective income tax rate. Estimates of the annual effective income tax rate at the end of interim periods are, out of necessity, based on evaluation of possible future events and transactions and may be subject to subsequent refinement or revision. The Company forecasts its estimated annual effective income tax rate and then applies that rate to its year-to-date pre-tax ordinary income (loss), subject to certain loss limitation provisions. In addition, certain specific transactions are excluded from the Company’s estimated annual effective tax rate computation, but are discretely recognized within income tax expense (benefit) in their respective interim period. Future changes in the forecasted annual income (loss) projections, tax rate changes, or discrete tax items could result in significant adjustments to quarterly income tax expense (benefit) in future periods. ​ The Company evaluates its deferred tax assets quarterly to determine if valuation allowances are required. In this evaluation, the Company considers 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 primarily related to depreciation and amortization that would occur within the same jurisdiction and during the carryforward period necessary to absorb the federal and state net operating losses and other deferred tax assets. ​ Deferred tax assets and liabilities are computed by applying the federal, provincial and state income tax rates in effect to the gross amounts of temporary differences and other tax attributes, such as net operating loss carry-forwards. In assessing if the deferred tax assets will be realized, the Company considers whether it is more likely than not that some or all of these deferred tax assets will be realized. The ultimate realization of deferred tax assets is dependent upon the generation of future taxable income during the period in which these deductible temporary differences reverse. ​ Earnings Per Share ​ Basic earnings per share is computed by dividing net income available to common stockholders by the weighted average number of outstanding shares of common stock for the period. Diluted earnings per share reflects the potential dilution that could occur if securities or other contracts to issue common stock, including stock options and restricted stock units (collectively “Common Stock Equivalents”), were exercised or converted into common stock. The dilutive effect of outstanding stock options and restricted stock units is reflected in diluted earnings per share by application of the treasury stock method. In applying the treasury stock method for stock-based compensation arrangements, the assumed proceeds are computed as the sum of the amount the employee must pay upon exercise and the amount of compensation cost attributed to future services and not yet recognized. Diluted earnings per share is computed by increasing the weighted-average number of outstanding shares of common stock computed in basic earnings per share to include the dilutive effect of Common Stock Equivalents for the period. In periods of net loss, the number of shares used to calculate diluted loss per share is the same as basic net loss per share. ​ The holders of the Company’s Exchangeable Shares (as defined in Note 8, “Stockholders’ Equity”) were entitled to receive dividends or distributions that are equal to any dividends or distributions on the Company’s common stock. As a result, when the Exchangeable Shares were outstanding, they were classified as a participating security and thereby required the allocation of income that would have otherwise been available to common stockholders when calculating earnings per share. Diluted earnings per share was calculated by utilizing the most dilutive result of the if-converted and two-class methods. In both methods, net income attributable to common stockholders and the weighted-average common shares outstanding are adjusted to account for the impact of the assumed issuance of potential common shares that are dilutive, subject to dilution sequencing rules. ​ Reclassifications ​ Certain amounts in the prior period financial statements have been reclassified to conform to the current year presentation. ​ Recently Adopted Accounting Pronouncements ​ Credit Losses – ​ Fair Value Measurement Disclosures – ​ Recently Issued Accounting Pronouncements ​ Reference Rate Reform

Revenue

Revenue	9 Months Ended
	Jan. 31, 2021
Revenue
Revenue	2. Revenue ​ Revenue Recognition ​ Revenue is recognized upon transfer of control of promised goods to customers at an amount that reflects the consideration the Company expects to receive in exchange for those goods. Revenue is recognized net of any taxes collected from customers, which are subsequently remitted to governmental authorities. The Company includes shipping and handling costs billed to customers in net sales. These costs are recognized as a component of selling, general and administrative expenses. ​ See Note 14, “Segments,” for information regarding disaggregation of revenue, including revenue by product and by geographic area. ​ Performance Obligations ​ The Company satisfies its performance obligations at a point in time, which is upon delivery of products. The Company’s payment terms vary by the type and location of its customers. The amount of time between point of sale and when payment is due is not significant and the Company has determined its contracts do not include a significant financing component. ​ The Company’s contracts with customers involve performance obligations that are one year or less. Therefore, the Company applied the standard’s optional exemption that permits the omission of information about its unfulfilled performance obligations as of the balance sheet dates. ​ Significant Judgments ​ The Company’s contracts may include terms that could cause variability in the transaction price, including customer rebates, returns and cash discounts for early payment. Variable consideration is estimated and included in the transaction price based on the expected value method. These estimates are based on historical experience, anticipated performance and other factors known at the time. The Company only includes estimated amounts in the transaction price to the extent it is probable that a significant reversal of cumulative revenue recognized will not occur when the uncertainty associated with the variable consideration is resolved. ​ Contract Balances ​ Receivables from contracts with customers, net of allowances, were $392.8 million and $393.6 million as of January 31, 2021 and April 30, 2020, respectively. The Company did not have material amounts of contract assets or liabilities as of January 31, 2021 or April 30, 2020. ​

Accounts Receivable

Accounts Receivable	9 Months Ended
	Jan. 31, 2021
Accounts Receivable
Accounts Receivable	3. Accounts Receivable ​ The Company’s trade accounts and notes receivable consisted of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ January 31, ​ April 30, ​ 2021 2020 ​ ​ (in thousands) Trade receivables ​ $ 398,794 ​ $ 398,739 Other receivables ​ 17,351 ​ 11,656 Allowance for expected credit losses ​ (3,308) ​ (2,861) Other allowances ​ (2,712) ​ ​ (2,280) Trade accounts and notes receivable ​ $ 410,125 ​ $ 405,254 ​ The Company records accounts and notes receivable net of allowances, including the allowance for expected credit losses. The Company maintains an allowance for estimated losses due to the failure of customers to make required payments, as well as allowances for cash discounts. The Company’s estimate of the allowance for expected credit losses is based on an assessment of individual past due accounts, historical loss information, accounts receivable aging and current economic factors and the Company’s expectation of future economic conditions. Account balances are written off when the potential for recovery is considered remote. Other receivables primarily includes vendor rebate receivables. Other allowances includes reserves for cash discounts and reserves for service charges. 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 geographically diverse customers comprising the Company’s customer base. ​ The following table presents the change in the allowance for expected credit losses during the nine months ended January 31, 2021: ​ ​ ​ ​ ​ ​ ​ (in thousands) Balance as of April 30, 2020 ​ $ 2,861 Provision ​ ​ 1,136 Write-offs ​ (689) Balance as of January 31, 2021 ​ $ 3,308 ​

Goodwill and Intangible Assets

Goodwill and Intangible Assets	9 Months Ended
	Jan. 31, 2021
Goodwill and Intangible Assets
Goodwill and Intangible Assets	4. Goodwill and Intangible Assets Goodwill The following table presents changes in the carrying amount of goodwill during the nine months ended January 31, 2021: ​ ​ ​ ​ ​ ​ Carrying ​ ​ Amount ​ ​ (in thousands) Balance as of April 30, 2020 ​ ​ ​ Goodwill ​ $ 616,147 Accumulated impairment loss ​ ​ (63,074) ​ ​ ​ 553,073 ​ ​ ​ ​ Working capital settlements ​ ​ (159) Translation adjustment ​ 9,290 ​ ​ ​ ​ Balance as of January 31, 2021 ​ ​ ​ Goodwill ​ ​ 625,278 Accumulated impairment loss ​ ​ (63,074) ​ ​ $ 562,204 ​ Intangible Assets The following tables present the components of the Company’s definite-lived intangible assets: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Estimated ​ Weighted ​ January 31, 2021 ​ ​ Useful ​ Average ​ Gross ​ ​ ​ Net ​ ​ Lives ​ Amortization ​ Carrying ​ Accumulated ​ Carrying ​ (years) Period Amount Amortization Value ​ ​ (dollars in thousands) Customer relationships ​ 5 - 16 ​ 12.8 ​ $ 537,256 ​ $ 314,191 ​ $ 223,065 Definite-lived tradenames ​ 5 - 20 ​ 16.3 ​ 58,203 ​ 13,603 ​ 44,600 Vendor agreements ​ 8 - 10 ​ 8.3 ​ 6,644 ​ 5,171 ​ 1,473 Developed technology ​ 5 ​ 4.9 ​ ​ 5,477 ​ ​ 2,970 ​ ​ 2,507 Other ​ 3 - 5 ​ 3.3 ​ ​ 4,390 ​ ​ 3,636 ​ ​ 754 Totals ​ ​ ​ ​ ​ $ 611,970 ​ $ 339,571 ​ $ 272,399 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Estimated ​ Weighted ​ April 30, 2020 ​ ​ Useful ​ Average ​ Gross ​ ​ ​ Net ​ ​ Lives Amortization Carrying Accumulated Carrying ​ (years) Period Amount Amortization Value ​ ​ (dollars in thousands) Customer relationships ​ 5 - 16 ​ 12.8 ​ $ 516,928 ​ $ 270,029 ​ $ 246,899 Definite-lived tradenames ​ 5 - 20 ​ 16.3 ​ 55,654 ​ 10,474 ​ 45,180 Vendor agreements ​ 8 - 10 ​ 8.3 ​ 6,644 ​ 4,567 ​ 2,077 Developed technology ​ 5 ​ 4.9 ​ ​ 5,036 ​ ​ 1,963 ​ ​ 3,073 Other ​ 1 - 15 ​ 5.3 ​ ​ 7,836 ​ ​ 4,548 ​ ​ 3,288 Totals ​ ​ ​ ​ ​ $ 592,098 ​ $ 291,581 ​ $ 300,517 ​ Definite-lived intangible assets are amortized over their estimated useful lives. The Company amortizes its customer relationships using an accelerated method to match the estimated cash flows generated by such assets, and amortizes its other definite-lived intangibles using the straight-line method because a pattern to which the expected benefits will be consumed or otherwise used up cannot be reliably determined. Amortization expense related to definite-lived intangible assets was $14.2 million and $16.5 million for the three months ended January 31, 2021 and 2020, respectively, and $43.0 million and $50.3 million for the nine months ended January 31, 2021 and 2020, respectively. Amortization expense is recorded in depreciation and amortization expense in the Condensed Consolidated Statements of Operations and Comprehensive Income. The following table summarizes the estimated future amortization expense for definite-lived intangible assets. Actual amortization expense to be reported in future periods could differ materially from these estimates as a result of acquisitions, changes in useful lives, foreign currency exchange rate fluctuations and other relevant factors. ​ ​ ​ ​ Year Ending April 30, (in thousands) 2021 (remaining three months) $ 13,088 2022 47,346 2023 39,511 2024 32,259 2025 26,682 Thereafter 113,513 Total $ 272,399 ​ The Company’s indefinite-lived intangible assets consist of tradenames that had a carrying amount of $61.4 million as of January 31, 2021 and April 30, 2020.

Long-Term Debt

Long-Term Debt	9 Months Ended
	Jan. 31, 2021
Long-Term Debt
Long-Term Debt	5. Long-Term Debt The Company’s long-term debt consisted of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ January 31, ​ April 30, ​ 2021 2020 ​ ​ (in thousands) Term Loan Facility ​ $ 869,426 ​ $ 876,903 Unamortized discount and deferred financing costs on Term Loan Facility ​ ​ (9,011) ​ ​ (10,602) ABL Facility ​ — ​ 80,000 Finance lease obligations ​ 122,020 ​ 128,767 Installment notes at fixed rates up to 5.0%, due in monthly and annual installments through 2024 ​ 12,544 ​ 16,316 Unamortized discount on installment notes ​ ​ (829) ​ ​ (1,098) Canadian Facility ​ — ​ ​ 7,194 Carrying value of debt ​ 994,150 ​ 1,097,480 Less current portion ​ 51,552 ​ 50,201 Long-term debt ​ $ 942,598 ​ $ 1,047,279 ​ Term Loan Facility ​ The Company has a senior secured first lien term loan facility (the “ ” Asset Based Lending Facility The Company has an asset based revolving credit facility (the “ABL Facility”) that provides for aggregate revolving commitments of $445.0 million (including same day swing line borrowings of $44.5 million). Extensions of credit under the ABL Facility are limited by a borrowing base calculated periodically based on specified percentages of the value of eligible inventory and eligible accounts receivable, subject to certain reserves and other adjustments. At the Company’s option, the interest rates applicable to the loans under the ABL Facility are based on LIBOR or base rate plus, in each case, an applicable margin. The margins applicable for each elected interest rate are subject to a pricing grid, as defined in the ABL Facility agreement, based on average daily availability for the most recent fiscal quarter. The ABL Facility also contains an unused commitment fee. As of January 31, 2021, the Company had available borrowing capacity of approximately $383.5 million under the ABL Facility. The ABL Facility matures on September 30, 2024 unless the individual affected lenders agree to extend the maturity of their respective loans under the ABL Facility upon the Company’s request and without the consent of any other lender. The ABL Facility contains a cross default provision with the Term Loan Facility. Covenants under the Term Loan Facility and ABL Facility The Term Loan Facility contains a number of covenants that limit our ability and the ability of our restricted subsidiaries, as described in the respective credit agreement, to: incur more indebtedness; pay dividends, redeem or repurchase stock or make other distributions; make investments; create restrictions on the ability of our restricted subsidiaries to pay dividends to us or make other intercompany transfers; create liens securing indebtedness; transfer or sell assets; merge or consolidate; enter into certain transactions with our affiliates; and prepay or amend the terms of certain indebtedness. The Company was in compliance with all restrictive covenants as of January 31, 2021. The ABL Facility contains certain affirmative covenants, including financial and other reporting requirements. The Company was in compliance with all such covenants as of January 31, 2021. Canadian Revolving Credit Facility Through its WSB Titan (“Titan”) subsidiary, the Company has a revolving credit facility (the “Canadian Facility”) that provides for aggregate revolving commitments of $23.5 million ($30.0 million Canadian dollars). The Canadian Facility bears interest at the Canadian prime rate plus a marginal rate based on the level determined by Titan ’ Debt Maturities As of January 31, 2021, the maturities of long-term debt were as follows ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Term Loan ​ Finance ​ Installment ​ ​ ​ ​ Facility Leases Notes ​ Total Year ending April 30, ​ (in thousands) 2021 (remaining three months) ​ $ 2,492 ​ $ 8,794 ​ $ 680 ​ $ 11,966 2022 ​ 9,968 ​ ​ 35,855 ​ ​ 4,538 ​ 50,361 2023 ​ 9,968 ​ ​ 30,660 ​ ​ 4,505 ​ 45,133 2024 ​ 9,968 ​ ​ 23,714 ​ ​ 1,881 ​ 35,563 2025 ​ 9,968 ​ ​ 13,763 ​ ​ 921 ​ 24,652 Thereafter ​ 827,062 ​ ​ 9,234 ​ ​ 19 ​ 836,315 ​ ​ $ 869,426 ​ $ 122,020 ​ $ 12,544 ​ $ 1,003,990 ​

Leases

Leases	9 Months Ended
	Jan. 31, 2021
Leases
Leases	6. Leases ​ The Company leases office and warehouse facilities, distribution equipment and its fleet of vehicles. The Company’s leases have lease terms ranging from one one Any payment deemed probable is included in the Company’s lease liability. The Company’s lease agreements do not contain any material restrictive covenants. ​ The Company determines if an arrangement is a lease at inception and evaluates whether the lease meets the classification criteria of a finance or operating lease. Operating leases are included in operating lease right-of-use assets, current portion of operating lease liabilities and long-term operating lease liabilities in the Condensed Consolidated Balance Sheets. Finance leases are included in property and equipment, current portion of long-term debt and long-term debt in the Condensed Consolidated Balance Sheets. ​ Lease ROU assets and lease liabilities are recognized at the commencement date based on the present value of the future lease payments over the lease term. For leases that do not provide an implicit rate, the Company uses its incremental borrowing rate in determining the present value of future payments. The Company determines its incremental borrowing rate based on the applicable lease terms and the current economic environment. Lease ROU assets also include any lease payments made in advance and excludes lease incentives and initial direct costs incurred. Some of the Company’s lease agreements contain rent escalation clauses (including index-based escalations), rent holidays, capital improvements funding or other lease concessions. Lease expense is recognized on a straight-line basis based on the fixed component over the lease term. Variable lease costs consist primarily of taxes, insurance and common area or other maintenance costs for leased facilities and vehicles and equipment, which are expensed as incurred. ​ The components of lease expense were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ Nine Months Ended ​ ​ January 31, ​ January 31, ​ ​ 2021 ​ 2020 ​ 2021 ​ 2020 ​ ​ (in thousands) Finance lease cost: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Amortization of right-of-use assets ​ $ 5,898 ​ $ 6,007 ​ $ 17,997 ​ $ 18,120 Interest on lease liabilities ​ ​ 2,748 ​ ​ 3,300 ​ ​ 8,673 ​ ​ 10,089 Operating lease cost ​ ​ 10,601 ​ ​ 10,646 ​ ​ 31,930 ​ ​ 31,555 Variable lease cost ​ ​ 3,197 ​ ​ 3,311 ​ ​ 9,329 ​ ​ 9,924 Total lease cost ​ $ 22,444 ​ $ 23,264 ​ $ 67,929 ​ $ 69,688 ​ Operating lease cost, including variable lease cost, is included in selling, general and administrative expenses; amortization of finance ROU assets is included in depreciation and amortization; and interest on finance lease liabilities is included in interest expense in the Condensed Consolidated Statements of Operations and Comprehensive Income. ​ Supplemental cash flow information related to leases was as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Nine Months Ended ​ ​ January 31, ​ ​ 2021 ​ 2020 ​ ​ (in thousands) Cash paid for amounts included in the measurement of lease liabilities ​ ​ ​ ​ ​ ​ Operating cash flows from operating leases ​ $ 32,208 ​ $ 30,976 Operating cash flows from finance leases ​ ​ 8,673 ​ ​ 10,089 Financing cash flows from finance leases ​ ​ 22,662 ​ ​ 17,971 Right-of-use assets obtained in exchange for lease obligations ​ ​ ​ ​ ​ ​ Operating leases ​ ​ 27,918 ​ ​ 32,042 Finance leases ​ ​ 22,408 ​ ​ 39,379 ​ Other information related to leases was as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ January 31, ​ April 30, ​ ​ ​ 2021 2020 ​ ​ ​ (in thousands) ​ Finance leases included in property and equipment ​ ​ ​ ​ ​ ​ ​ Property and equipment ​ $ 176,529 ​ $ 171,380 ​ Accumulated depreciation ​ ​ (49,717) ​ ​ (41,737) ​ Property and equipment, net ​ $ 126,812 ​ $ 129,643 ​ Weighted-average remaining lease term (years) ​ ​ ​ ​ ​ ​ ​ Operating leases ​ ​ 4.8 ​ ​ 4.9 ​ Finance leases ​ ​ 3.5 ​ ​ 3.6 ​ Weighted-average discount rate ​ ​ ​ ​ ​ ​ ​ Operating leases ​ ​ 5.5 % ​ 5.5 % Finance leases ​ ​ 4.9 % ​ 5.0 % ​ Future minimum lease payments under non-cancellable leases as of January 31, 2021 were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ Finance Operating Year Ending April 30, ​ (in thousands) 2021 (remaining three months) ​ $ 11,216 ​ $ 10,494 2022 ​ 43,251 ​ 36,897 2023 ​ 34,553 ​ 30,224 2024 ​ 25,279 ​ 24,785 2025 ​ 14,296 ​ 17,423 Thereafter ​ 9,387 ​ 23,445 Total lease payments ​ ​ 137,982 ​ ​ 143,268 Less imputed interest ​ 15,962 ​ 18,312 Total ​ $ 122,020 ​ $ 124,956 ​

Income Taxes

Income Taxes	9 Months Ended
	Jan. 31, 2021
Income Taxes
Income Taxes	7. Income Taxes General. Valuation allowance Uncertain tax positions ​ ​

Stockholders' Equity

Stockholders' Equity	9 Months Ended
	Jan. 31, 2021
Stockholders' Equity
Stockholders' Equity	8. Stockholders’ Equity Exchangeable Shares In connection with the acquisition of Titan on June 1, 2018, the Company issued 1.1 million shares of equity that were exchangeable for the Company’s common stock on a one-for-one basis (“Exchangeable Shares”). The Exchangeable Shares were issued by an indirect wholly-owned subsidiary of the Company. The Exchangeable Shares ranked senior to the Company’s common stock with respect to dividend rights and rights on liquidation, dissolution and winding-up. The holders of the Exchangeable Shares were entitled to receive dividends or distributions that were equal to any dividends or distributions on the Company’s common stock. The holders of the Exchangeable Shares did not have voting rights. The Exchangeable Shares contained rights that allowed the holders to exchange their Exchangeable Shares for GMS common stock at any time on a one-for-one basis. On June 13, 2019, the holders of the Exchangeable Shares exchanged all of the Exchangeable Shares for 1.1 million shares of the Company’s common stock. Following such exchange, the Exchangeable Shares ceased to be outstanding. Share Repurchase Program The Company has a common stock repurchase program authorized by its Board of Directors to repurchase up to $75.0 million of outstanding common stock. The Company may conduct repurchases under the share repurchase program through open market transactions, under trading plans in accordance with SEC Rule 10b5-1 and/or in privately negotiated transactions, in compliance with Rule 10b-18 under the Exchange Act of 1934, as amended. These repurchases are subject to a variety of factors, including, but not limited to, our liquidity, credit availability, general business and market conditions, our debt covenant restrictions and the availability of alternative investment opportunities. The share repurchase program does not obligate us to acquire any particular amount of common stock, and it may be suspended or terminated at any time at the Company’s discretion. The Company repurchased approximately 80,000 shares of its common stock for $2.0 million during the nine months ended January 31, 2021. The Company did not repurchase any shares of its common stock during the nine months ended January 31, 2020. As of January 31, 2021, the Company had $56.5 million of remaining repurchase authorization under the stock repurchase program. Accumulated Other Comprehensive Loss The following table sets forth the changes to accumulated other comprehensive loss, net of tax, by component for the nine months ended January 31, 2021: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Accumulated ​ ​ Foreign ​ Derivative ​ Other ​ ​ Currency ​ Financial ​ Comprehensive ​ ​ Translation ​ Instruments ​ Loss ​ ​ (in thousands) Balance as of April 30, 2020 ​ $ (40,577) ​ $ (24,505) ​ $ (65,082) Other comprehensive income (loss) before reclassification ​ ​ 39,813 ​ ​ (763) ​ ​ 39,050 Reclassification to earnings from accumulated other comprehensive loss ​ ​ — ​ ​ 6,540 ​ 6,540 Balance as of January 31, 2021 ​ $ (764) ​ $ (18,728) ​ $ (19,492) ​ Other comprehensive loss on derivative instruments for the nine months ended January 31, 2021 is net of $0.2 million of tax and reclassification to earnings from accumulated other comprehensive loss is net of $2.1 million of tax.

Equity-Based Compensation

Equity-Based Compensation	9 Months Ended
	Jan. 31, 2021
Equity-Based Compensation
Equity-Based Compensation	9. Equity-Based Compensation General The Company measures compensation cost for all share-based awards at fair value on the grant date (or measurement date if different) and recognizes compensation expense, net of estimated forfeitures, over the requisite service period for awards expected to vest. The Company estimates the fair value of stock options using the Black-Scholes valuation model, and determines the fair value of restricted stock units based on the quoted price of GMS ’ . Equity-based compensation expense related to stock options and restricted stock units was $6.3 million and $4.8 million during the nine months ended January 31, 2021 and 2020, respectively, and is included in selling, general and administrative expenses in the Condensed Consolidated Statements of Operations and Comprehensive Income. Stock Option Awards The following table presents stock option activity for the nine months ended January 31, 2021: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ ​ ​ ​ ​ ​ Weighted ​ Average ​ ​ ​ ​ ​ ​ ​ Average ​ Remaining ​ Aggregate ​ ​ Number of ​ Exercise ​ Contractual ​ Intrinsic ​ ​ Options ​ Price ​ Life (years) ​ Value ​ ​ (shares and dollars in thousands) Outstanding as of April 30, 2020 1,487 ​ $ 18.85 6.4 ​ $ 3,895 Options granted 321 ​ ​ 23.43 ​ Options exercised (195) ​ 17.53 ​ Options forfeited (48) ​ 25.97 ​ Outstanding as of January 31, 2021 1,565 ​ $ 19.73 6.5 ​ $ 14,933 Exercisable as of January 31, 2021 948 ​ $ 17.65 4.9 ​ $ 11,176 Vested and expected to vest as of January 31, 2021 1,558 ​ $ 19.72 6.5 ​ $ 14,895 ​ The aggregate intrinsic value represents the excess of the Company’s closing stock price on the last trading day of the period over the weighted average exercise price multiplied by the number of options outstanding, exercisable or expected to vest. Options expected to vest are unvested shares net of expected forfeitures. The total intrinsic value of options exercised during the nine months ended January The fair value weighted average grant date fair value ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Nine Months Ended ​ ​ January 31, ​ ​ 2021 ​ 2020 Volatility ​ 51.28 % ​ 49.86 % Expected life (years) ​ 6.0 ​ ​ 6.0 ​ Risk-free interest rate ​ 0.30 % ​ 1.97 % Dividend yield ​ — % ​ — % Grant date fair value ​ $ 11.13 ​ ​ $ 10.59 ​ ​ ​ Restricted Stock Units The following table presents restricted stock unit activity for the nine months ended January 31, 2021: ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ ​ Number of ​ Average ​ ​ Restricted ​ Grant Date ​ ​ Stock Units ​ Fair Value ​ ​ (shares in thousands) Outstanding as of April 30, 2020 ​ 286 ​ $ 22.71 Granted ​ 214 ​ ​ 23.48 Vested ​ (110) ​ ​ 23.21 Forfeited ​ (28) ​ ​ 23.93 Outstanding as of January 31, 2021 ​ 362 ​ $ 22.92 ​ As of January 31, 2021, there was $5.2 million of total unrecognized compensation cost related to nonvested restricted stock units. That cost is expected to be recognized over a weighted-average period of 1.8 years. Employee Stock Purchase Plan ​ The Company has an employee stock purchase plan (“ESPP”), the terms of which allow for qualified employees to participate in the purchase of shares of the Company’s common stock at a price equal to 90% of the lower of the closing price at the beginning or end of the purchase period, which is a six-month period ending on December 31 and June 30 of each year. During the nine months ended January 31, 2021, 0.1 million shares of the Company’s common stock were purchased under the ESPP at a price of $21.78 per share. The Company recognized $0.4 million and $0.4 million of stock-based compensation expense during the nine months ended January 31, 2021 and 2020, respectively, related to the ESPP.

Stock Appreciation Rights, Defe

Stock Appreciation Rights, Deferred Compensation and Redeemable Noncontrolling Interests	9 Months Ended
	Jan. 31, 2021
Stock Appreciation Rights, Deferred Compensation and Redeemable Noncontrolling Interests
Stock Appreciation Rights, Deferred Compensation and Redeemable Noncontrolling Interests	10. Stock Appreciation Rights, Deferred Compensation and Redeemable Noncontrolling Interests The following table presents a summary of changes to the liabilities for stock appreciation rights, deferred compensation and redeemable noncontrolling interests for the nine months ended January 31, 2021: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Stock ​ ​ ​ ​ Redeemable ​ ​ Appreciation ​ Deferred ​ Noncontrolling ​ Rights Compensation Interests ​ ​ (in thousands) Balance as of April 30, 2020 ​ $ 24,205 ​ $ 1,660 ​ $ 8,300 Amounts redeemed ​ (583) ​ — ​ — Change in fair value ​ 2,552 ​ 177 ​ 885 Balance as of January 31, 2021 ​ $ 26,174 ​ $ 1,837 ​ $ 9,185 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Classified as current as of April 30, 2020 ​ $ 624 ​ $ — ​ $ — Classified as long-term as of April 30, 2020 ​ ​ 23,581 ​ ​ 1,660 ​ ​ 8,300 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Classified as current as of January 31, 2021 ​ $ 1,200 ​ $ — ​ $ — Classified as long-term as of January 31, 2021 ​ ​ 24,974 ​ ​ 1,837 ​ ​ 9,185 ​ Total expense related to these instruments was $3.6 million and $1.3 million during the nine months ended January 31, 2021 and 2020, respectively, and was included in selling, general and administrative expenses in the Condensed Consolidated Statements of Operations and Comprehensive Income. The Company uses a lognormal binomial method to determine the fair value of stock appreciation rights, deferred compensation and redeemable noncontrolling interests at redemption date. Significant inputs used in this method include volatility rates, a discount rate, the expected time to redemption of the liabilities, historical values of the book equity of certain subsidiaries and market information for comparable entities. The use of these inputs to derive the fair value of the liabilities at a point in time can result in volatility to the financial statements. Stock Appreciation Rights Certain subsidiaries have granted stock appreciation rights to certain employees under which payments are dependent on the appreciation in the book value per share, adjusted for certain provisions, of the applicable subsidiary. Settlements of the awards can be made in a combination of cash or installment notes, generally paid over five years, upon a triggering event. As of January 31, 2021, all stock appreciation rights were vested. Liabilities related to these agreements are classified as share-based liability awards and are measured at fair value. Deferred Compensation Subsidiaries’ stockholders have entered into other deferred compensation agreements that granted the stockholders a payment based on a percentage in excess of book value, adjusted for certain provisions, upon an occurrence as defined in the related agreements. These instruments are redeemed in cash or installment notes, generally paid in annual installments over the five years following termination of employment. Liabilities related to these agreements are classified as share-based liability awards and are measured at fair value. Redeemable Noncontrolling Interests Noncontrolling interests were issued to certain employees of certain of the Company’s subsidiaries. All of the noncontrolling interest awards are subject to mandatory redemption on termination of employment for any reason. These instruments are redeemed in cash or installment notes, generally paid in annual installments over the five years following termination of employment. Liabilities related to these agreements are classified as share-based liability awards and are measured at fair value. Under the terms of the employee agreements, the redemption value is determined based on the book value of the subsidiary, as adjusted for certain items. Upon the termination of employment or other triggering events including death or disability of the noncontrolling stockholders in the Company’s subsidiaries, we are obligated to purchase, or redeem, the noncontrolling interests at either an agreed upon price or a formula value provided in the stockholder agreements. This formula value is typically based on the book value per share of the subsidiary’s equity, including certain adjustments.

Fair Value Measurements

Fair Value Measurements	9 Months Ended
	Jan. 31, 2021
Fair Value Measurements
Fair Value Measurements	11. Fair Value Measurements Assets and Liabilities Measured at Fair Value on a Recurring Basis The following table presents the estimated carrying amount and fair value of the Company’s liabilities measured at fair value on a recurring basis: ​ ​ ​ ​ ​ ​ ​ ​ ​ January 31, ​ April 30, ​ ​ 2021 ​ 2020 ​ ​ (in thousands) Interest rate swaps (Level 2) ​ $ 24,566 ​ $ 32,218 ​ The Company has interest rate swap agreements with a notional amount of $500.0 million that convert the variable interest rate on its Term Loan Facility to a fixed interest rate . The contracts were effective on and terminate on rate swaps as a cash flow hedges. The Company believes there have been no material changes in the creditworthiness of the counterparty to this interest rate swap and believes the risk of nonperformance by such party is minimal. ​ As of January 31, 2021, $11.9 million of the interest rate swap liability was classified in other accrued expenses and current liabilities and $12.6 million was classified in other liabilities in the Condensed Consolidated Balance Sheet. The Company recognized losses, net of tax, of $2.2 million and $6.5 million in earnings during the three and nine months ended January 31, 2021, respectively, related to its interest rate swaps. These losses are included in interest expense in the Condensed Consolidated Statements of Operations and Comprehensive Income. As of January 31, 2021, the Company expects that approximately $11.9 million of pre-tax net losses will be reclassified from accumulated other comprehensive income (loss) into earnings during the next twelve months. ​ The fair value of interest rate swaps is determined using Level 2 inputs. Generally, the Company obtains the Level 2 inputs from its counterparties. Substantially all of the inputs throughout the full term of the instruments can be derived from observable data or are supported by observable levels at which transactions are executed in the marketplace. The fair value of the Company’s interest rate swap 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. ​ Assets and Liabilities Measured at Fair Value on a Nonrecurring Basis Disclosures are required for certain assets and liabilities that are measured at fair value on a nonrecurring basis in periods subsequent to initial recognition. Such measurements of fair value relate primarily to assets and liabilities measured at fair value in connection with business combinations and long-lived asset impairments. The Company recorded a $1.0 million impairment of operating lease ROU assets during the nine months ended January 31, 2021. There were no other material long-lived asset impairments during the nine months ended January 31, 2021 or 2020.

Transactions With Related Parti

Transactions With Related Parties	9 Months Ended
	Jan. 31, 2021
Transactions With Related Parties
Transactions With Related Parties	12. Transactions With Related Parties The Company purchases inventories from Southern Wall Products, Inc. (“SWP”) on a continuing basis. During the nine months ended January 31, 2021 and 2020 certain former executive officers and stockholders and certain directors and stockholders of the Company were stockholders of SWP. As of October 31, 2020, these executive officers and directors were no longer with the Company. The Company purchased inventory from SWP for distribution in the amount of $3.2 million during the three months ended January 31, 2020 and $7.3 million and $10.5 million during the nine months ended January 31, 2021 and 2020, respectively. The amount due to SWP for purchases of inventory for distribution was $1.2 million as of April 30, 2020 and is included in accounts payable in the Condensed Consolidated Balance Sheet.

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Jan. 31, 2021
Commitments and Contingencies
Commitments and Contingencies	13. Commitments and Contingencies ​ General ​ The Company is a defendant in various lawsuits and administrative actions associated with personal injuries, claims of former employees and other events arising in the normal course of business. As discussed in Note 1 “—Insurance Liabilities”, the Company records liabilities for these claims, and assets for amounts recoverable from the insurer, for claims covered by insurance. ​ Favorable Class Action Settlement ​ In November 2020, the Company received proceeds as part of a class action settlement against certain drywall manufacturers related to purchases made during calendar years 2012 and 2013. The Company recorded a gain on legal settlement of $1.4 million during the three and nine months ended January 31, 2021. This was the final payment related to this class action settlement. ​

Segments

Segments	9 Months Ended
	Jan. 31, 2021
Segments
Segments	14. Segments General The Company has eight operating segments based on geographic operations that it aggregates into one reportable segment. The Company defines operating segments as components of the organization for which discrete financial information is available and operating results are evaluated on a regular basis by the Chief Operating Decision Maker (“CODM”) in order to assess performance and allocate resources. The Company’s CODM is its Chief Executive Officer. The Company determined it has eight operating segments based on the Company’s eight geographic divisions, which are Central, Midwest, Northeast, Southern, Southeast, Southwest, Western and Canada. During the nine months ended January 31, 2021, the Company divided its Southern operating segment into two operating segments, Southern and Southwest, which resulted in an increase (from seven to eight) in the number of operating segments. The Company performed a goodwill impairment test immediately before and after the change in operating segments, which indicated the fair values of the Company’s reporting units exceeded their carrying values. The Company aggregates its operating segments into a single reportable segment based on similarities between the operating segments’ economic characteristics, nature of products sold, production process, type of customer and methods of distribution. The accounting policies of the operating segments are the same as those described in the summary of significant policies. In addition to the Company’s reportable segment, the Company’s consolidated results include both corporate activities and certain other activities. Corporate includes the Company’s corporate office building and support services provided to its subsidiaries. Other includes Tool Source Warehouse, Inc., which functions primarily as an internal distributor of tools. Segment Results The CODM assesses the Company’s performance based on the periodic review of net sales, Adjusted EBITDA and certain other measures for each of the operating segments. Adjusted EBITDA is not a recognized financial measure under GAAP. However, we believe it assists investors and analysts in comparing our operating performance across reporting periods on a consistent basis by excluding items that we do not believe are indicative of our core operating performance. Management believes Adjusted EBITDA is helpful in highlighting trends in our operating results, while other measures can differ significantly depending on long-term strategic decisions regarding capital structure, the tax jurisdictions in which companies operate and capital investments. See “Management’s Discussion and Analysis of Financial Condition and Results of Operations -- Non-GAAP Financial Measures” for a further discussion of this non-GAAP measure. The following tables present segment results: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended January 31, 2021 ​ ​ ​ ​ ​ ​ Depreciation and ​ Adjusted ​ ​ Net Sales ​ Gross Profit ​ Amortization ​ EBITDA ​ ​ (in thousands) Geographic divisions ​ $ 741,885 ​ $ 240,536 ​ $ 24,942 ​ $ 61,916 Other ​ ​ 9,306 ​ 2,788 ​ 92 ​ ​ 671 Corporate ​ ​ — ​ — ​ 528 ​ ​ — ​ ​ $ 751,191 ​ $ 243,324 ​ $ 25,562 ​ $ 62,587 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended January 31, 2020 ​ ​ ​ ​ ​ ​ Depreciation and ​ Adjusted ​ ​ Net Sales ​ Gross Profit ​ Amortization ​ EBITDA ​ ​ (in thousands) Geographic divisions ​ $ 754,916 ​ $ 251,086 ​ $ 28,791 ​ $ 62,169 Other ​ 6,436 ​ 2,387 ​ 56 ​ ​ 528 Corporate ​ — ​ — ​ 575 ​ ​ — ​ ​ $ 761,352 ​ $ 253,473 ​ $ 29,422 ​ $ 62,697 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Nine Months Ended January 31, 2021 ​ ​ ​ ​ ​ ​ Depreciation and ​ Adjusted ​ ​ Net Sales ​ Gross Profit ​ Amortization ​ EBITDA ​ ​ (in thousands) Geographic divisions ​ $ 2,341,430 ​ $ 760,908 ​ $ 78,507 ​ $ 226,588 Other ​ 25,190 ​ 7,945 ​ 274 ​ ​ 1,575 Corporate ​ — ​ — ​ 1,123 ​ ​ — ​ ​ $ 2,366,620 ​ $ 768,853 ​ $ 79,904 ​ $ 228,163 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Nine Months Ended January 31, 2020 ​ ​ ​ ​ ​ Depreciation and ​ Adjusted ​ ​ Net Sales ​ Gross Profit ​ Amortization ​ EBITDA ​ ​ (in thousands) Geographic divisions ​ $ 2,449,926 ​ $ 804,340 ​ $ 86,747 ​ $ 234,422 Other ​ 20,531 ​ 7,280 ​ 164 ​ ​ 1,768 Corporate ​ — ​ — ​ 1,304 ​ ​ — ​ ​ $ 2,470,457 ​ $ 811,620 ​ $ 88,215 ​ $ 236,190 ​ The following table presents a reconciliation of Adjusted EBITDA to net income: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ Nine Months Ended ​ ​ January 31, ​ January 31, ​ 2021 2020 ​ 2021 ​ 2020 ​ ​ (in thousands) Net income ​ $ 16,126 ​ $ 10,879 ​ $ 71,814 ​ $ 64,837 Interest expense ​ 13,454 ​ 16,474 ​ 41,060 ​ 52,310 Write-off of debt discount and deferred financing fees ​ ​ — ​ ​ — ​ ​ — ​ ​ 707 Interest income ​ (6) ​ (8) ​ (57) ​ (26) Provision for income taxes ​ 5,709 ​ 2,816 ​ 23,590 ​ 18,333 Depreciation expense ​ 11,371 ​ 12,930 ​ 36,908 ​ 37,944 Amortization expense ​ 14,191 ​ 16,492 ​ 42,996 ​ 50,271 Stock appreciation rights(a) ​ ​ 1,446 ​ ​ (347) ​ ​ 2,552 ​ ​ 980 Redeemable noncontrolling interests(b) ​ 624 ​ (318) ​ 1,062 ​ 326 Equity-based compensation(c) ​ 1,877 ​ 1,465 ​ 6,734 ​ 5,175 Severance and other permitted costs(d) ​ (83) ​ 1,700 ​ 2,626 ​ 3,648 Transaction costs (acquisitions and other)(e) ​ 664 ​ 434 ​ 789 ​ 1,733 Gain on disposal and impairment of assets(f) ​ (1,404) ​ (130) ​ (529) ​ (872) Effects of fair value adjustments to inventory(g) ​ — ​ 310 ​ — ​ 461 Gain on legal settlement ​ ​ (1,382) ​ ​ — ​ ​ (1,382) ​ ​ — Secondary public offering costs(h) ​ ​ — ​ ​ — ​ ​ — ​ ​ 363 Adjusted EBITDA ​ $ 62,587 ​ $ 62,697 ​ $ 228,163 ​ $ 236,190 (a) Represents changes in the fair value of stock appreciation rights. (b) Represents changes in the fair value of noncontrolling interests . (c) Represents non-cash equity-based compensation expense related to the issuance of share-based awards. (d) Represents severance expenses and other costs permitted in the calculation of Adjusted EBITDA under the ABL Facility and the Term Loan Facility, including certain unusual, nonrecurring costs and credits received due to the COVID-19 pandemic. (e) Represents costs related to acquisitions paid to third parties. (f) Includes gains from the sale of assets and impairment of assets resulting from restructuring plans to close certain facilities. (g) Represents the non-cash cost of sales impact of acquisition accounting adjustments to increase inventory to its estimated fair value. (h) Represents costs paid to third-party advisors related to secondary offerings of our common stock. Revenues by Product The following table presents the Company’s net sales to external customers by main product lines: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ Nine Months Ended ​ ​ January 31, ​ January 31, ​ ​ 2021 ​ 2020 ​ 2021 2020 ​ ​ (in thousands) Wallboard $ 311,122 $ 314,391 $ 969,634 ​ $ 1,006,604 Ceilings ​ 101,909 112,768 326,904 364,685 Steel framing ​ 103,956 118,823 325,736 386,811 Other products ​ 234,204 215,370 744,346 712,357 Total net sales ​ $ 751,191 $ 761,352 $ 2,366,620 $ 2,470,457 ​ Geographic Information ​ The following table presents the Company’s net sales by major geographic area: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ Nine Months Ended ​ ​ January 31, ​ January 31, ​ 2021 2020 ​ 2021 2020 ​ ​ (in thousands) United States ​ $ 637,568 $ 661,491 $ 2,001,020 ​ $ 2,136,968 Canada ​ 113,623 99,861 365,600 ​ ​ 333,489 Total net sales ​ $ 751,191 $ 761,352 ​ $ 2,366,620 ​ $ 2,470,457 ​ The following table presents the Company’s property and equipment, net, by major geographic area: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ January 31, ​ April 30, ​ 2021 2020 ​ ​ (in thousands) United States ​ $ 268,826 ​ $ 270,855 Canada ​ 36,318 34,612 Total property and equipment, net ​ $ 305,144 $ 305,467 ​

Earnings Per Common Share

Earnings Per Common Share	9 Months Ended
	Jan. 31, 2021
Earnings Per Common Share
Earnings Per Common Share	15. Earnings Per Common Share The following table sets forth the computation of basic and diluted earnings per share of common stock: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ Nine Months Ended ​ ​ January 31, ​ January 31, ​ 2021 ​ 2020 2021 2020 ​ ​ (in thousands, except per share data) Net income ​ $ 16,126 ​ $ 10,879 ​ $ 71,814 ​ $ 64,837 Less: Net income allocated to participating securities ​ ​ — ​ ​ — ​ ​ — ​ ​ 273 Net income attributable to common stockholders ​ $ 16,126 $ 10,879 ​ $ 71,814 ​ $ 64,564 Basic earnings per common share: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Basic weighted average common shares outstanding ​ 42,726 ​ 42,223 ​ 42,691 ​ 41,663 Basic earnings per common share ​ $ 0.38 ​ $ 0.26 ​ $ 1.68 ​ $ 1.55 Diluted earnings per common share: ​ ​ ​ ​ Basic weighted average common shares outstanding ​ 42,726 ​ 42,223 ​ 42,691 ​ 41,663 Add: Common Stock Equivalents ​ 635 ​ 726 ​ 493 ​ 738 Diluted weighted average common shares outstanding ​ 43,361 ​ 42,949 ​ 43,184 ​ 42,401 Diluted earnings per common share ​ $ 0.37 ​ $ 0.25 ​ $ 1.66 ​ $ 1.52 ​ ​ During the three and nine months ended January 31, 2021, approximately 0.3 million and 0.4 million, respectively, Common Stock Equivalents were excluded from the calculation of diluted earnings per share because their effect would have been anti-dilutive. Anti-dilutive securities could be dilutive in future periods.

Subsequent Event

Subsequent Event	9 Months Ended
	Jan. 31, 2021
Subsequent Event
Subsequent Event	16. Subsequent Event ​ On February 1, 2021, the Company acquired D.L. Building Materials, Inc. (“D.L. Building Materials”) for a purchase price of approximately $39.1 million ($50.0 million Canadian dollars). D.L. Building Materials distributes wallboard, acoustical ceilings, steel framing, insulation and related building products in the Eastern Ontario and Western Quebec markets through two locations in Gatineau, Quebec and Kingston, Ontario. ​

Business, Basis of Presentati_2

Business, Basis of Presentation and Summary of Significant Accounting Policies (Policies)	9 Months Ended
	Jan. 31, 2021
Business, Basis of Presentation and Summary of Significant Accounting Policies
Basis of Presentation	Basis of Presentation ​ The condensed consolidated financial statements included in this Quarterly Report on Form 10-Q have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”) that permit reduced disclosure for interim periods. In the opinion of management, the accompanying unaudited condensed consolidated financial statements contain all normal and recurring adjustments necessary for a fair presentation of the results of operations, financial position and cash flows. All adjustments are of a normal recurring nature unless otherwise disclosed. The results of operations for interim periods are not necessarily indicative of results for any other interim period or the entire fiscal year. As a result, the unaudited condensed consolidated financial statements should be read in conjunction with our audited consolidated financial statements included in our Annual Report on Form 10-K for the fiscal year ended April 30, 2020. ​
Principles of Consolidation	Principles of Consolidation ​ The condensed consolidated financial statements present the results of operations, financial position, stockholders’ equity and cash flows of the Company and its subsidiaries. All material intercompany balances and transactions have been eliminated in consolidation. The results of operations of businesses acquired are included from their respective dates of acquisition. ​
Use of Estimates	Use of Estimates ​ The preparation of financial statements in conformity with Generally Accepted Accounting Principles (“GAAP”) requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities as of 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. ​
Foreign Currency Translation	Foreign Currency Translation ​ Assets and liabilities of the Company’s Canadian subsidiaries are translated at the exchange rate prevailing at the balance sheet date, while income and expenses are translated at average rates for the period. Translation gains and losses are reported as a separate component of stockholders’ equity and other comprehensive income. Gains and losses on foreign currency transactions are recognized in the Condensed Consolidated Statements of Operations and Comprehensive Income within other (expense) income, net. ​
Insurance Liabilities	Insurance Liabilities ​ The Company is self-insured for certain losses related to medical claims. The Company has stop-loss coverage to limit the exposure arising from medical claims. In addition, the Company has deductible-based insurance policies for certain losses related to general liability, workers’ compensation and automobile. The coverage consists of a deductible layer, a primary layer, a self-insured buffer layer, a lead umbrella layer and excess layers. The deductible amount per incident is $0.3 million, $0.5 million and $1.0 million for general liability, workers’ compensation and automobile, respectively. The primary layer of coverage is from $0.3 million, $0.5 million and $1.0 million for general liability, workers’ compensation, and automobile liability, respectively, to $5.0 million. The Company self-insures a buffer layer from $5.0 million to $10.0 million. The umbrella and excess layers cover claims from $10.0 million to $100.0 million. 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 historical loss development factors and actuarial assumptions followed in the insurance industry. The following table presents the Company’s aggregate liabilities for medical self-insurance, reserves for general liability, automobile and workers’ compensation and the expected recoveries for medical self-insurance, general liability, automobile and workers’ compensation. Liabilities for medical self-insurance are included in other accrued expenses and current liabilities. Reserves for general liability, automobile and workers’ compensation are included in other accrued expenses and current liabilities and other liabilities. Expected recoveries for insurance liabilities are included in prepaid expenses and other current assets and other assets in the Condensed Consolidated Balance Sheets. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ January 31, ​ April 30, ​ ​ 2021 2020 ​ ​ (in thousands) Medical self‑insurance ​ $ 3,778 ​ $ 3,770 General liability, automobile and workers’ compensation ​ ​ 20,520 ​ ​ 19,410 Expected recoveries for insurance liabilities ​ (7,813) ​ (6,037)
Income Taxes	Income Taxes ​ The Company considers each interim period an integral part of the annual period and measures tax expense (benefit) using an estimated annual effective income tax rate. Estimates of the annual effective income tax rate at the end of interim periods are, out of necessity, based on evaluation of possible future events and transactions and may be subject to subsequent refinement or revision. The Company forecasts its estimated annual effective income tax rate and then applies that rate to its year-to-date pre-tax ordinary income (loss), subject to certain loss limitation provisions. In addition, certain specific transactions are excluded from the Company’s estimated annual effective tax rate computation, but are discretely recognized within income tax expense (benefit) in their respective interim period. Future changes in the forecasted annual income (loss) projections, tax rate changes, or discrete tax items could result in significant adjustments to quarterly income tax expense (benefit) in future periods. ​ The Company evaluates its deferred tax assets quarterly to determine if valuation allowances are required. In this evaluation, the Company considers 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 primarily related to depreciation and amortization that would occur within the same jurisdiction and during the carryforward period necessary to absorb the federal and state net operating losses and other deferred tax assets. ​ Deferred tax assets and liabilities are computed by applying the federal, provincial and state income tax rates in effect to the gross amounts of temporary differences and other tax attributes, such as net operating loss carry-forwards. In assessing if the deferred tax assets will be realized, the Company considers whether it is more likely than not that some or all of these deferred tax assets will be realized. The ultimate realization of deferred tax assets is dependent upon the generation of future taxable income during the period in which these deductible temporary differences reverse.
Earnings Per Share	Earnings Per Share ​ Basic earnings per share is computed by dividing net income available to common stockholders by the weighted average number of outstanding shares of common stock for the period. Diluted earnings per share reflects the potential dilution that could occur if securities or other contracts to issue common stock, including stock options and restricted stock units (collectively “Common Stock Equivalents”), were exercised or converted into common stock. The dilutive effect of outstanding stock options and restricted stock units is reflected in diluted earnings per share by application of the treasury stock method. In applying the treasury stock method for stock-based compensation arrangements, the assumed proceeds are computed as the sum of the amount the employee must pay upon exercise and the amount of compensation cost attributed to future services and not yet recognized. Diluted earnings per share is computed by increasing the weighted-average number of outstanding shares of common stock computed in basic earnings per share to include the dilutive effect of Common Stock Equivalents for the period. In periods of net loss, the number of shares used to calculate diluted loss per share is the same as basic net loss per share. ​ The holders of the Company’s Exchangeable Shares (as defined in Note 8, “Stockholders’ Equity”) were entitled to receive dividends or distributions that are equal to any dividends or distributions on the Company’s common stock. As a result, when the Exchangeable Shares were outstanding, they were classified as a participating security and thereby required the allocation of income that would have otherwise been available to common stockholders when calculating earnings per share. Diluted earnings per share was calculated by utilizing the most dilutive result of the if-converted and two-class methods. In both methods, net income attributable to common stockholders and the weighted-average common shares outstanding are adjusted to account for the impact of the assumed issuance of potential common shares that are dilutive, subject to dilution sequencing rules.
Reclassifications	Reclassifications ​ Certain amounts in the prior period financial statements have been reclassified to conform to the current year presentation.
Recently Adopted Accounting Pronouncements	Recently Adopted Accounting Pronouncements ​ Credit Losses – ​ Fair Value Measurement Disclosures – ​ Recently Issued Accounting Pronouncements ​ Reference Rate Reform

Business, Basis of Presentati_3

Business, Basis of Presentation and Summary of Significant Accounting Policies (Tables)	9 Months Ended
	Jan. 31, 2021
Business, Basis of Presentation and Summary of Significant Accounting Policies
Schedule of medical self-insurance liabilities and recoveries	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ January 31, ​ April 30, ​ ​ 2021 2020 ​ ​ (in thousands) Medical self‑insurance ​ $ 3,778 ​ $ 3,770 General liability, automobile and workers’ compensation ​ ​ 20,520 ​ ​ 19,410 Expected recoveries for insurance liabilities ​ (7,813) ​ (6,037)

Accounts Receivable (Tables)

Accounts Receivable (Tables)	9 Months Ended
	Jan. 31, 2021
Accounts Receivable
Schedule of trade accounts and notes receivable	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ January 31, ​ April 30, ​ 2021 2020 ​ ​ (in thousands) Trade receivables ​ $ 398,794 ​ $ 398,739 Other receivables ​ 17,351 ​ 11,656 Allowance for expected credit losses ​ (3,308) ​ (2,861) Other allowances ​ (2,712) ​ ​ (2,280) Trade accounts and notes receivable ​ $ 410,125 ​ $ 405,254
Schedule of change in allowance for expected credit losses	​ ​ ​ ​ ​ ​ ​ (in thousands) Balance as of April 30, 2020 ​ $ 2,861 Provision ​ ​ 1,136 Write-offs ​ (689) Balance as of January 31, 2021 ​ $ 3,308

Goodwill and Intangible Assets

Goodwill and Intangible Assets (Tables)	9 Months Ended
	Jan. 31, 2021
Goodwill and Intangible Assets
Schedule of changes in the carrying amount of goodwill	​ ​ ​ ​ ​ ​ Carrying ​ ​ Amount ​ ​ (in thousands) Balance as of April 30, 2020 ​ ​ ​ Goodwill ​ $ 616,147 Accumulated impairment loss ​ ​ (63,074) ​ ​ ​ 553,073 ​ ​ ​ ​ Working capital settlements ​ ​ (159) Translation adjustment ​ 9,290 ​ ​ ​ ​ Balance as of January 31, 2021 ​ ​ ​ Goodwill ​ ​ 625,278 Accumulated impairment loss ​ ​ (63,074) ​ ​ $ 562,204
Schedule of components of definite-lived intangible assets	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Estimated ​ Weighted ​ January 31, 2021 ​ ​ Useful ​ Average ​ Gross ​ ​ ​ Net ​ ​ Lives ​ Amortization ​ Carrying ​ Accumulated ​ Carrying ​ (years) Period Amount Amortization Value ​ ​ (dollars in thousands) Customer relationships ​ 5 - 16 ​ 12.8 ​ $ 537,256 ​ $ 314,191 ​ $ 223,065 Definite-lived tradenames ​ 5 - 20 ​ 16.3 ​ 58,203 ​ 13,603 ​ 44,600 Vendor agreements ​ 8 - 10 ​ 8.3 ​ 6,644 ​ 5,171 ​ 1,473 Developed technology ​ 5 ​ 4.9 ​ ​ 5,477 ​ ​ 2,970 ​ ​ 2,507 Other ​ 3 - 5 ​ 3.3 ​ ​ 4,390 ​ ​ 3,636 ​ ​ 754 Totals ​ ​ ​ ​ ​ $ 611,970 ​ $ 339,571 ​ $ 272,399 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Estimated ​ Weighted ​ April 30, 2020 ​ ​ Useful ​ Average ​ Gross ​ ​ ​ Net ​ ​ Lives Amortization Carrying Accumulated Carrying ​ (years) Period Amount Amortization Value ​ ​ (dollars in thousands) Customer relationships ​ 5 - 16 ​ 12.8 ​ $ 516,928 ​ $ 270,029 ​ $ 246,899 Definite-lived tradenames ​ 5 - 20 ​ 16.3 ​ 55,654 ​ 10,474 ​ 45,180 Vendor agreements ​ 8 - 10 ​ 8.3 ​ 6,644 ​ 4,567 ​ 2,077 Developed technology ​ 5 ​ 4.9 ​ ​ 5,036 ​ ​ 1,963 ​ ​ 3,073 Other ​ 1 - 15 ​ 5.3 ​ ​ 7,836 ​ ​ 4,548 ​ ​ 3,288 Totals ​ ​ ​ ​ ​ $ 592,098 ​ $ 291,581 ​ $ 300,517 ​
Schedule of estimated future aggregate amortization expense	​ ​ ​ ​ Year Ending April 30, (in thousands) 2021 (remaining three months) $ 13,088 2022 47,346 2023 39,511 2024 32,259 2025 26,682 Thereafter 113,513 Total $ 272,399

Long-Term Debt (Tables)

Long-Term Debt (Tables)	9 Months Ended
	Jan. 31, 2021
Long-Term Debt
Schedule of long-term debt	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ January 31, ​ April 30, ​ 2021 2020 ​ ​ (in thousands) Term Loan Facility ​ $ 869,426 ​ $ 876,903 Unamortized discount and deferred financing costs on Term Loan Facility ​ ​ (9,011) ​ ​ (10,602) ABL Facility ​ — ​ 80,000 Finance lease obligations ​ 122,020 ​ 128,767 Installment notes at fixed rates up to 5.0%, due in monthly and annual installments through 2024 ​ 12,544 ​ 16,316 Unamortized discount on installment notes ​ ​ (829) ​ ​ (1,098) Canadian Facility ​ — ​ ​ 7,194 Carrying value of debt ​ 994,150 ​ 1,097,480 Less current portion ​ 51,552 ​ 50,201 Long-term debt ​ $ 942,598 ​ $ 1,047,279
Scheduled of maturities of long-term debt	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Term Loan ​ Finance ​ Installment ​ ​ ​ ​ Facility Leases Notes ​ Total Year ending April 30, ​ (in thousands) 2021 (remaining three months) ​ $ 2,492 ​ $ 8,794 ​ $ 680 ​ $ 11,966 2022 ​ 9,968 ​ ​ 35,855 ​ ​ 4,538 ​ 50,361 2023 ​ 9,968 ​ ​ 30,660 ​ ​ 4,505 ​ 45,133 2024 ​ 9,968 ​ ​ 23,714 ​ ​ 1,881 ​ 35,563 2025 ​ 9,968 ​ ​ 13,763 ​ ​ 921 ​ 24,652 Thereafter ​ 827,062 ​ ​ 9,234 ​ ​ 19 ​ 836,315 ​ ​ $ 869,426 ​ $ 122,020 ​ $ 12,544 ​ $ 1,003,990

Leases (Tables)

Leases (Tables)	9 Months Ended
	Jan. 31, 2021
Leases
Summary of components of lease expense	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ Nine Months Ended ​ ​ January 31, ​ January 31, ​ ​ 2021 ​ 2020 ​ 2021 ​ 2020 ​ ​ (in thousands) Finance lease cost: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Amortization of right-of-use assets ​ $ 5,898 ​ $ 6,007 ​ $ 17,997 ​ $ 18,120 Interest on lease liabilities ​ ​ 2,748 ​ ​ 3,300 ​ ​ 8,673 ​ ​ 10,089 Operating lease cost ​ ​ 10,601 ​ ​ 10,646 ​ ​ 31,930 ​ ​ 31,555 Variable lease cost ​ ​ 3,197 ​ ​ 3,311 ​ ​ 9,329 ​ ​ 9,924 Total lease cost ​ $ 22,444 ​ $ 23,264 ​ $ 67,929 ​ $ 69,688
Summary of components of supplemental cash flow information related to leases	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Nine Months Ended ​ ​ January 31, ​ ​ 2021 ​ 2020 ​ ​ (in thousands) Cash paid for amounts included in the measurement of lease liabilities ​ ​ ​ ​ ​ ​ Operating cash flows from operating leases ​ $ 32,208 ​ $ 30,976 Operating cash flows from finance leases ​ ​ 8,673 ​ ​ 10,089 Financing cash flows from finance leases ​ ​ 22,662 ​ ​ 17,971 Right-of-use assets obtained in exchange for lease obligations ​ ​ ​ ​ ​ ​ Operating leases ​ ​ 27,918 ​ ​ 32,042 Finance leases ​ ​ 22,408 ​ ​ 39,379
Summary of other lease information	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ January 31, ​ April 30, ​ ​ ​ 2021 2020 ​ ​ ​ (in thousands) ​ Finance leases included in property and equipment ​ ​ ​ ​ ​ ​ ​ Property and equipment ​ $ 176,529 ​ $ 171,380 ​ Accumulated depreciation ​ ​ (49,717) ​ ​ (41,737) ​ Property and equipment, net ​ $ 126,812 ​ $ 129,643 ​ Weighted-average remaining lease term (years) ​ ​ ​ ​ ​ ​ ​ Operating leases ​ ​ 4.8 ​ ​ 4.9 ​ Finance leases ​ ​ 3.5 ​ ​ 3.6 ​ Weighted-average discount rate ​ ​ ​ ​ ​ ​ ​ Operating leases ​ ​ 5.5 % ​ 5.5 % Finance leases ​ ​ 4.9 % ​ 5.0 %
Schedule of maturities for finance leases	​ ​ ​ ​ ​ ​ ​ ​ ​ Finance Operating Year Ending April 30, ​ (in thousands) 2021 (remaining three months) ​ $ 11,216 ​ $ 10,494 2022 ​ 43,251 ​ 36,897 2023 ​ 34,553 ​ 30,224 2024 ​ 25,279 ​ 24,785 2025 ​ 14,296 ​ 17,423 Thereafter ​ 9,387 ​ 23,445 Total lease payments ​ ​ 137,982 ​ ​ 143,268 Less imputed interest ​ 15,962 ​ 18,312 Total ​ $ 122,020 ​ $ 124,956
Schedule of maturities for operating leases	​ ​ ​ ​ ​ ​ ​ ​ ​ Finance Operating Year Ending April 30, ​ (in thousands) 2021 (remaining three months) ​ $ 11,216 ​ $ 10,494 2022 ​ 43,251 ​ 36,897 2023 ​ 34,553 ​ 30,224 2024 ​ 25,279 ​ 24,785 2025 ​ 14,296 ​ 17,423 Thereafter ​ 9,387 ​ 23,445 Total lease payments ​ ​ 137,982 ​ ​ 143,268 Less imputed interest ​ 15,962 ​ 18,312 Total ​ $ 122,020 ​ $ 124,956

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	9 Months Ended
	Jan. 31, 2021
Stockholders' Equity
Schedule of changes to accumulated other comprehensive loss, net of tax, by component	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Accumulated ​ ​ Foreign ​ Derivative ​ Other ​ ​ Currency ​ Financial ​ Comprehensive ​ ​ Translation ​ Instruments ​ Loss ​ ​ (in thousands) Balance as of April 30, 2020 ​ $ (40,577) ​ $ (24,505) ​ $ (65,082) Other comprehensive income (loss) before reclassification ​ ​ 39,813 ​ ​ (763) ​ ​ 39,050 Reclassification to earnings from accumulated other comprehensive loss ​ ​ — ​ ​ 6,540 ​ 6,540 Balance as of January 31, 2021 ​ $ (764) ​ $ (18,728) ​ $ (19,492)

Equity-Based Compensation - (Ta

Equity-Based Compensation - (Tables)	9 Months Ended
	Jan. 31, 2021
Equity-Based Compensation
Summary of stock option activity	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ ​ ​ ​ ​ ​ Weighted ​ Average ​ ​ ​ ​ ​ ​ ​ Average ​ Remaining ​ Aggregate ​ ​ Number of ​ Exercise ​ Contractual ​ Intrinsic ​ ​ Options ​ Price ​ Life (years) ​ Value ​ ​ (shares and dollars in thousands) Outstanding as of April 30, 2020 1,487 ​ $ 18.85 6.4 ​ $ 3,895 Options granted 321 ​ ​ 23.43 ​ Options exercised (195) ​ 17.53 ​ Options forfeited (48) ​ 25.97 ​ Outstanding as of January 31, 2021 1,565 ​ $ 19.73 6.5 ​ $ 14,933 Exercisable as of January 31, 2021 948 ​ $ 17.65 4.9 ​ $ 11,176 Vested and expected to vest as of January 31, 2021 1,558 ​ $ 19.72 6.5 ​ $ 14,895
Schedule of weighted average assumptions used in Black-Scholes option-pricing model	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Nine Months Ended ​ ​ January 31, ​ ​ 2021 ​ 2020 Volatility ​ 51.28 % ​ 49.86 % Expected life (years) ​ 6.0 ​ ​ 6.0 ​ Risk-free interest rate ​ 0.30 % ​ 1.97 % Dividend yield ​ — % ​ — % Grant date fair value ​ $ 11.13 ​ ​ $ 10.59 ​
Summary of restricted stock unity activity	​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ ​ Number of ​ Average ​ ​ Restricted ​ Grant Date ​ ​ Stock Units ​ Fair Value ​ ​ (shares in thousands) Outstanding as of April 30, 2020 ​ 286 ​ $ 22.71 Granted ​ 214 ​ ​ 23.48 Vested ​ (110) ​ ​ 23.21 Forfeited ​ (28) ​ ​ 23.93 Outstanding as of January 31, 2021 ​ 362 ​ $ 22.92

Stock Appreciation Rights, De_2

Stock Appreciation Rights, Deferred Compensation and Redeemable Noncontrolling Interests (Tables)	9 Months Ended
	Jan. 31, 2021
Stock Appreciation Rights, Deferred Compensation and Redeemable Noncontrolling Interests
Summary of changes to the liabilities for stock appreciation rights, deferred compensation and redeemable noncontrolling interests	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Stock ​ ​ ​ ​ Redeemable ​ ​ Appreciation ​ Deferred ​ Noncontrolling ​ Rights Compensation Interests ​ ​ (in thousands) Balance as of April 30, 2020 ​ $ 24,205 ​ $ 1,660 ​ $ 8,300 Amounts redeemed ​ (583) ​ — ​ — Change in fair value ​ 2,552 ​ 177 ​ 885 Balance as of January 31, 2021 ​ $ 26,174 ​ $ 1,837 ​ $ 9,185 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Classified as current as of April 30, 2020 ​ $ 624 ​ $ — ​ $ — Classified as long-term as of April 30, 2020 ​ ​ 23,581 ​ ​ 1,660 ​ ​ 8,300 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Classified as current as of January 31, 2021 ​ $ 1,200 ​ $ — ​ $ — Classified as long-term as of January 31, 2021 ​ ​ 24,974 ​ ​ 1,837 ​ ​ 9,185

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	9 Months Ended
	Jan. 31, 2021
Fair Value Measurements
Schedule of liabilities measured at fair value on a recurring basis	​ ​ ​ ​ ​ ​ ​ ​ ​ January 31, ​ April 30, ​ ​ 2021 ​ 2020 ​ ​ (in thousands) Interest rate swaps (Level 2) ​ $ 24,566 ​ $ 32,218

Segments (Tables)

Segments (Tables)	9 Months Ended
	Jan. 31, 2021
Segments
Schedule of segment results	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended January 31, 2021 ​ ​ ​ ​ ​ ​ Depreciation and ​ Adjusted ​ ​ Net Sales ​ Gross Profit ​ Amortization ​ EBITDA ​ ​ (in thousands) Geographic divisions ​ $ 741,885 ​ $ 240,536 ​ $ 24,942 ​ $ 61,916 Other ​ ​ 9,306 ​ 2,788 ​ 92 ​ ​ 671 Corporate ​ ​ — ​ — ​ 528 ​ ​ — ​ ​ $ 751,191 ​ $ 243,324 ​ $ 25,562 ​ $ 62,587 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended January 31, 2020 ​ ​ ​ ​ ​ ​ Depreciation and ​ Adjusted ​ ​ Net Sales ​ Gross Profit ​ Amortization ​ EBITDA ​ ​ (in thousands) Geographic divisions ​ $ 754,916 ​ $ 251,086 ​ $ 28,791 ​ $ 62,169 Other ​ 6,436 ​ 2,387 ​ 56 ​ ​ 528 Corporate ​ — ​ — ​ 575 ​ ​ — ​ ​ $ 761,352 ​ $ 253,473 ​ $ 29,422 ​ $ 62,697 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Nine Months Ended January 31, 2021 ​ ​ ​ ​ ​ ​ Depreciation and ​ Adjusted ​ ​ Net Sales ​ Gross Profit ​ Amortization ​ EBITDA ​ ​ (in thousands) Geographic divisions ​ $ 2,341,430 ​ $ 760,908 ​ $ 78,507 ​ $ 226,588 Other ​ 25,190 ​ 7,945 ​ 274 ​ ​ 1,575 Corporate ​ — ​ — ​ 1,123 ​ ​ — ​ ​ $ 2,366,620 ​ $ 768,853 ​ $ 79,904 ​ $ 228,163 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Nine Months Ended January 31, 2020 ​ ​ ​ ​ ​ Depreciation and ​ Adjusted ​ ​ Net Sales ​ Gross Profit ​ Amortization ​ EBITDA ​ ​ (in thousands) Geographic divisions ​ $ 2,449,926 ​ $ 804,340 ​ $ 86,747 ​ $ 234,422 Other ​ 20,531 ​ 7,280 ​ 164 ​ ​ 1,768 Corporate ​ — ​ — ​ 1,304 ​ ​ — ​ ​ $ 2,470,457 ​ $ 811,620 ​ $ 88,215 ​ $ 236,190
Reconciliation of Adjusted EBITDA to net income	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ Nine Months Ended ​ ​ January 31, ​ January 31, ​ 2021 2020 ​ 2021 ​ 2020 ​ ​ (in thousands) Net income ​ $ 16,126 ​ $ 10,879 ​ $ 71,814 ​ $ 64,837 Interest expense ​ 13,454 ​ 16,474 ​ 41,060 ​ 52,310 Write-off of debt discount and deferred financing fees ​ ​ — ​ ​ — ​ ​ — ​ ​ 707 Interest income ​ (6) ​ (8) ​ (57) ​ (26) Provision for income taxes ​ 5,709 ​ 2,816 ​ 23,590 ​ 18,333 Depreciation expense ​ 11,371 ​ 12,930 ​ 36,908 ​ 37,944 Amortization expense ​ 14,191 ​ 16,492 ​ 42,996 ​ 50,271 Stock appreciation rights(a) ​ ​ 1,446 ​ ​ (347) ​ ​ 2,552 ​ ​ 980 Redeemable noncontrolling interests(b) ​ 624 ​ (318) ​ 1,062 ​ 326 Equity-based compensation(c) ​ 1,877 ​ 1,465 ​ 6,734 ​ 5,175 Severance and other permitted costs(d) ​ (83) ​ 1,700 ​ 2,626 ​ 3,648 Transaction costs (acquisitions and other)(e) ​ 664 ​ 434 ​ 789 ​ 1,733 Gain on disposal and impairment of assets(f) ​ (1,404) ​ (130) ​ (529) ​ (872) Effects of fair value adjustments to inventory(g) ​ — ​ 310 ​ — ​ 461 Gain on legal settlement ​ ​ (1,382) ​ ​ — ​ ​ (1,382) ​ ​ — Secondary public offering costs(h) ​ ​ — ​ ​ — ​ ​ — ​ ​ 363 Adjusted EBITDA ​ $ 62,587 ​ $ 62,697 ​ $ 228,163 ​ $ 236,190 (a) Represents changes in the fair value of stock appreciation rights. (b) Represents changes in the fair value of noncontrolling interests . (c) Represents non-cash equity-based compensation expense related to the issuance of share-based awards. (d) Represents severance expenses and other costs permitted in the calculation of Adjusted EBITDA under the ABL Facility and the Term Loan Facility, including certain unusual, nonrecurring costs and credits received due to the COVID-19 pandemic. (e) Represents costs related to acquisitions paid to third parties. (f) Includes gains from the sale of assets and impairment of assets resulting from restructuring plans to close certain facilities. (g) Represents the non-cash cost of sales impact of acquisition accounting adjustments to increase inventory to its estimated fair value. (h) Represents costs paid to third-party advisors related to secondary offerings of our common stock.
Schedule of net sales to external customers by main product lines	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ Nine Months Ended ​ ​ January 31, ​ January 31, ​ ​ 2021 ​ 2020 ​ 2021 2020 ​ ​ (in thousands) Wallboard $ 311,122 $ 314,391 $ 969,634 ​ $ 1,006,604 Ceilings ​ 101,909 112,768 326,904 364,685 Steel framing ​ 103,956 118,823 325,736 386,811 Other products ​ 234,204 215,370 744,346 712,357 Total net sales ​ $ 751,191 $ 761,352 $ 2,366,620 $ 2,470,457
Schedule of net sales by major geographic area	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ Nine Months Ended ​ ​ January 31, ​ January 31, ​ 2021 2020 ​ 2021 2020 ​ ​ (in thousands) United States ​ $ 637,568 $ 661,491 $ 2,001,020 ​ $ 2,136,968 Canada ​ 113,623 99,861 365,600 ​ ​ 333,489 Total net sales ​ $ 751,191 $ 761,352 ​ $ 2,366,620 ​ $ 2,470,457
Schedule of property and equipment by major geographic area	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ January 31, ​ April 30, ​ 2021 2020 ​ ​ (in thousands) United States ​ $ 268,826 ​ $ 270,855 Canada ​ 36,318 34,612 Total property and equipment, net ​ $ 305,144 $ 305,467

Earnings Per Common Share (Tabl

Earnings Per Common Share (Tables)	9 Months Ended
	Jan. 31, 2021
Earnings Per Common Share
Schedule of computation of basic and diluted earnings per share of common stock	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ Nine Months Ended ​ ​ January 31, ​ January 31, ​ 2021 ​ 2020 2021 2020 ​ ​ (in thousands, except per share data) Net income ​ $ 16,126 ​ $ 10,879 ​ $ 71,814 ​ $ 64,837 Less: Net income allocated to participating securities ​ ​ — ​ ​ — ​ ​ — ​ ​ 273 Net income attributable to common stockholders ​ $ 16,126 $ 10,879 ​ $ 71,814 ​ $ 64,564 Basic earnings per common share: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Basic weighted average common shares outstanding ​ 42,726 ​ 42,223 ​ 42,691 ​ 41,663 Basic earnings per common share ​ $ 0.38 ​ $ 0.26 ​ $ 1.68 ​ $ 1.55 Diluted earnings per common share: ​ ​ ​ ​ Basic weighted average common shares outstanding ​ 42,726 ​ 42,223 ​ 42,691 ​ 41,663 Add: Common Stock Equivalents ​ 635 ​ 726 ​ 493 ​ 738 Diluted weighted average common shares outstanding ​ 43,361 ​ 42,949 ​ 43,184 ​ 42,401 Diluted earnings per common share ​ $ 0.37 ​ $ 0.25 ​ $ 1.66 ​ $ 1.52

Business, Basis of Presentati_4

Business, Basis of Presentation and Summary of Significant Accounting Policies - Business (Details)	9 Months Ended
	Jan. 31, 2021item
Business
Number of distribution centers	265

Business, Basis of Presentati_5

Business, Basis of Presentation and Summary of Significant Accounting Policies - Insurance Liabilities (Details) - USD ($) $ in Thousands	Jan. 31, 2021	Apr. 30, 2020
General liability
Insurance Liabilities
Deductible amount	$ 300
Primary layer of insurance coverage	300
Workers' compensation
Insurance Liabilities
Deductible amount	500
Primary layer of insurance coverage	500
Automobile
Insurance Liabilities
Deductible amount	1,000
Primary layer of insurance coverage	1,000
General liability, workers' compensation and automobile | Other accrued expenses and current liabilities.
Insurance Liabilities
Medical self-insurance	3,778	$ 3,770
General liability, automobile and workers' compensation	20,520	19,410
General liability, workers' compensation and automobile | Prepaid expenses and other current assets
Insurance Liabilities
Expected recoveries for insurance liabilities	(7,813)	$ (6,037)
General liability, workers' compensation and automobile | Minimum
Insurance Liabilities
Buffer layer of insurance coverage	5,000
Excess layer of insurance coverage	10,000
General liability, workers' compensation and automobile | Maximum
Insurance Liabilities
Primary layer of insurance coverage	5,000
Buffer layer of insurance coverage	10,000
Excess layer of insurance coverage	$ 100,000

Revenue (Details)

Revenue (Details) - USD ($) $ in Millions	9 Months Ended
	Jan. 31, 2021	Apr. 30, 2020
Revenue
Revenue, Practical Expedient, Financing Component [true false]	true
Revenue, Practical Expedient, Remaining Performance Obligation [true/false]	true
Receivables from contracts with customers	$ 392.8	$ 393.6

Accounts Receivable - Trade Acc

Accounts Receivable - Trade Accounts And Notes Receivable (Details) - USD ($) $ in Thousands	Jan. 31, 2021	Apr. 30, 2020
Accounts Receivable
Trade receivables	$ 398,794	$ 398,739
Other receivables	17,351	11,656
Allowance for expected credit losses	(3,308)	(2,861)
Other allowances	(2,712)	(2,280)
Trade accounts and notes receivable	$ 410,125	$ 405,254

Accounts Receivable - Change In

Accounts Receivable - Change In Allowance (Details) $ in Thousands	9 Months Ended
	Jan. 31, 2021USD ($)
Change in allowance
Beginning balance	$ 2,861
Ending balance	3,308
Accounts receivable.
Change in allowance
Beginning balance	2,861
Provision	1,136
Write-offs	(689)
Ending balance	$ 3,308

Goodwill and Intangible Asset_2

Goodwill and Intangible Assets - Goodwill (Details) $ in Thousands	9 Months Ended
	Jan. 31, 2021USD ($)
Carrying Amount of Goodwill
Goodwill	$ 616,147
Accumulated impairment loss	(63,074)
Balance	553,073
Working capital settlement	(159)
Translation adjustment	9,290
Goodwill	625,278
Accumulated impairment loss	(63,074)
Balance	$ 562,204

Goodwill and Intangible Asset_3

Goodwill and Intangible Assets - Definite-Lived Intangible Assets (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Jan. 31, 2021	Apr. 30, 2020
Definite-lived intangible assets
Gross Carrying Amount	$ 611,970	$ 592,098
Accumulated Amortization	339,571	291,581
Total	$ 272,399	$ 300,517
Customer relationships
Definite-lived intangible assets
Weighted Average Amortization Period (in years)	12 years 9 months 18 days	12 years 9 months 18 days
Gross Carrying Amount	$ 537,256	$ 516,928
Accumulated Amortization	314,191	270,029
Total	$ 223,065	$ 246,899
Customer relationships | Minimum
Definite-lived intangible assets
Estimated Useful Lives (years)	5 years	5 years
Customer relationships | Maximum
Definite-lived intangible assets
Estimated Useful Lives (years)	16 years	16 years
Tradenames
Definite-lived intangible assets
Weighted Average Amortization Period (in years)	16 years 3 months 18 days	16 years 3 months 18 days
Gross Carrying Amount	$ 58,203	$ 55,654
Accumulated Amortization	13,603	10,474
Total	$ 44,600	$ 45,180
Tradenames | Minimum
Definite-lived intangible assets
Estimated Useful Lives (years)	5 years	5 years
Tradenames | Maximum
Definite-lived intangible assets
Estimated Useful Lives (years)	20 years	20 years
Vendor agreements
Definite-lived intangible assets
Weighted Average Amortization Period (in years)	8 years 3 months 18 days	8 years 3 months 18 days
Gross Carrying Amount	$ 6,644	$ 6,644
Accumulated Amortization	5,171	4,567
Total	$ 1,473	$ 2,077
Vendor agreements | Minimum
Definite-lived intangible assets
Estimated Useful Lives (years)	8 years	8 years
Vendor agreements | Maximum
Definite-lived intangible assets
Estimated Useful Lives (years)	10 years	10 years
Developed technology
Definite-lived intangible assets
Estimated Useful Lives (years)	5 years	5 years
Weighted Average Amortization Period (in years)	4 years 10 months 24 days	4 years 10 months 24 days
Gross Carrying Amount	$ 5,477	$ 5,036
Accumulated Amortization	2,970	1,963
Total	$ 2,507	$ 3,073
Other intangible assets
Definite-lived intangible assets
Weighted Average Amortization Period (in years)	3 years 3 months 18 days	5 years 3 months 18 days
Gross Carrying Amount	$ 4,390	$ 7,836
Accumulated Amortization	3,636	4,548
Total	$ 754	$ 3,288
Other intangible assets | Minimum
Definite-lived intangible assets
Estimated Useful Lives (years)	3 years	1 year
Other intangible assets | Maximum
Definite-lived intangible assets
Estimated Useful Lives (years)	5 years	15 years

Goodwill and Intangible Asset_4

Goodwill and Intangible Assets - Amortization (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jan. 31, 2021	Jan. 31, 2020	Jan. 31, 2021	Jan. 31, 2020
Intangible assets
Amortization expense	$ 14,191	$ 16,492	$ 42,996	$ 50,271
Depreciation and amortization expense
Intangible assets
Amortization expense	$ 14,200	$ 16,500	$ 43,000	$ 50,300

Goodwill and Intangible Asset_5

Goodwill and Intangible Assets - Estimated Aggregate Amortization Expense (Details) - USD ($) $ in Thousands	Jan. 31, 2021	Apr. 30, 2020
Estimated aggregate future amortization expense
2021 (remaining three months)	$ 13,088
2022	47,346
2023	39,511
2024	32,259
2025	26,682
Thereafter	113,513
Total	$ 272,399	$ 300,517

Goodwill and Intangible Asset_6

Goodwill and Intangible Assets - Indefinite-Lived Intangible Assets (Details) - USD ($) $ in Millions	Oct. 31, 2020	Apr. 30, 2020
Goodwill and Intangible Assets
Tradenames	$ 61.4	$ 61.4

Long-Term Debt - Components (De

Long-Term Debt - Components (Details) - USD ($) $ in Thousands	Jan. 31, 2021	Apr. 30, 2020
Long-term debt
Carrying value of debt	$ 994,150	$ 1,097,480
Less current portion	51,552	50,201
Long-term debt	942,598	1,047,279
Term Loan Facility
Long-term debt
Carrying value of debt	869,426	876,903
Unamortized discount and deferred financing costs	(9,011)	(10,602)
ABL Facility
Long-term debt
Carrying value of debt		80,000
Finance lease obligations
Long-term debt
Carrying value of debt	122,020	128,767
Installment notes
Long-term debt
Carrying value of debt	12,544	16,316
Unamortized discount	$ (829)	$ (1,098)
Interest rate	5.00%	5.00%
Canadian Facility
Long-term debt
Carrying value of debt		$ 7,194

Long-Term Debt - Acquisition De

Long-Term Debt - Acquisition Debt (Details) - Term Loan Facility $ in Millions	9 Months Ended
	Jan. 31, 2021USD ($)
Long-term debt
Borrowing interest rate (as a percent)	2.87%
Loan quarterly payments	$ 2.5
Loan quarterly payments of the principal amount (as a percent)	0.25%
LIBOR
Long-term debt
Margin added to variable rate (as a percent)	2.75%
Variable rate floor (as a percent)	0.00%

Long-Term Debt - Asset-Based Le

Long-Term Debt - Asset-Based Lending Facility (Details) - ABL Facility $ in Millions	Jan. 31, 2021USD ($)
Long-term debt
Maximum amount under the facility	$ 445
Available borrowings under the facility	383.5
Swing-line
Long-term debt
Maximum amount under the facility	$ 44.5

Long-Term Debt - Canadian Revol

Long-Term Debt - Canadian Revolving Credit Facility (Details) - Canadian Facility $ in Millions, $ in Millions	Jan. 31, 2021USD ($)	Jun. 01, 2018USD ($)	Jun. 01, 2018CAD ($)
Debt Instrument [Line Items]
Maximum amount under the facility		$ 23.5	$ 30
Available borrowings under the facility	$ 23.5

Long-Term Debt - Maturities (De

Long-Term Debt - Maturities (Details) $ in Thousands	Jan. 31, 2021USD ($)
Debt maturities
2021 (remaining three months)	$ 11,966
2022	50,361
2023	45,133
2024	35,563
2025	24,652
Thereafter	836,315
Total	1,003,990
Term Loan Facility
Debt maturities
2021 (remaining three months)	2,492
2022	9,968
2023	9,968
2024	9,968
2025	9,968
Thereafter	827,062
Total	869,426
Finance lease obligations
Debt maturities
2021 (remaining three months)	8,794
2022	35,855
2023	30,660
2024	23,714
2025	13,763
Thereafter	9,234
Total	122,020
Installment notes
Debt maturities
2021 (remaining three months)	680
2022	4,538
2023	4,505
2024	1,881
2025	921
Thereafter	19
Total	$ 12,544

Leases (Details)

Leases (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jan. 31, 2021	Jan. 31, 2020	Jan. 31, 2021	Jan. 31, 2020
Leases
Option to extend			true
Finance lease cost:
Amortization of right-of-use assets	$ 5,898	$ 6,007	$ 17,997	$ 18,120
Interest on lease liabilities	2,748	3,300	8,673	10,089
Operating lease cost	10,601	10,646	31,930	31,555
Variable lease cost	3,197	3,311	9,329	9,924
Total lease cost	$ 22,444	$ 23,264	$ 67,929	$ 69,688
Minimum
Leases
Lease term (in years)	1 year		1 year
Renewal lease term (in years)	1 year		1 year
Maximum
Leases
Lease term (in years)	11 years		11 years
Renewal lease term (in years)	5 years		5 years

Leases - Supplemental cash flow

Leases - Supplemental cash flow information (Details) - USD ($) $ in Thousands	9 Months Ended
	Jan. 31, 2021	Jan. 31, 2020
Cash paid for amounts included in the measurement of lease liabilities
Operating cash flows from operating leases	$ 32,208	$ 30,976
Operating cash flows from finance leases	8,673	10,089
Financing cash flows from finance leases	22,662	17,971
Right-of-use assets obtained in exchange for lease obligations - Operating leases	27,918	32,042
Right-of-use assets obtained in exchange for lease obligations - Finance leases	$ 22,408	$ 39,379

Leases - Other information (Det

Leases - Other information (Details) - USD ($) $ in Thousands	Jan. 31, 2021	Apr. 30, 2020
Finance leases included in property and equipment
Accumulated depreciation	$ (184,410)	$ (158,554)
Property and equipment, net	$ 305,144	$ 305,467
Weighted-average remaining lease term (years) - Operating leases	4 years 9 months 18 days	4 years 10 months 24 days
Weighted-average remaining lease term (years) - Finance leases	3 years 6 months	3 years 7 months 6 days
Weighted-average discount rate - Operating leases	5.50%	5.50%
Weighted-average discount rate - Finance leases	4.90%	5.00%
Finance Leased Assets
Finance leases included in property and equipment
Property and equipment	$ 176,529	$ 171,380
Accumulated depreciation	(49,717)	(41,737)
Property and equipment, net	$ 126,812	$ 129,643

Leases - Future minimum lease p

Leases - Future minimum lease payments under non-cancellable leases (Details) $ in Thousands	Jan. 31, 2021USD ($)
Finance lease
2021 (remaining three months)	$ 11,216
2022	43,251
2023	34,553
2024	25,279
2025	14,296
Thereafter	9,387
Total lease payments	137,982
Less imputed interest	15,962
Total	122,020
Operating lease
2021 (remaining three months)	10,494
2022	36,897
2023	30,224
2024	24,785
2025	17,423
Thereafter	23,445
Total lease payments	143,268
Less imputed interest	18,312
Total	$ 124,956

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Millions	9 Months Ended
	Jan. 31, 2021	Jan. 31, 2020	Apr. 30, 2020
Effective income tax rate (as a percent)	24.70%	22.00%
Valuation allowance	$ 10.7		$ 10.2
Reserve for uncertain tax positions	$ 0		$ 0
Domestic
Federal statutory rate (as a percent)	21.00%

Stockholders' Equity - Exchange

Stockholders' Equity - Exchangeable Shares, Share Repurchase Program and Secondary Public Offering (Details) $ in Millions	Jun. 13, 2019shares	Jun. 01, 2018shares	Jan. 31, 2021USD ($)shares	Nov. 30, 2018USD ($)
Exchangeable Shares and Share Repurchase Program
Number of shares repurchased | shares			80,000
Shares repurchased, cost | $			$ 2
Remaining amount under repurchase program | $			$ 56.5
Maximum
Exchangeable Shares and Share Repurchase Program
Stock repurchase program, authorized amount | $				$ 75
Titan
Exchangeable Shares and Share Repurchase Program
Issuance of shares to current shareholders of Titan (in shares) | shares		1,100,000
Exchangeable shares conversion ratio		1
Exchangeable shares converted | shares	1,100,000

Stockholders' Equity - Accumula

Stockholders' Equity - Accumulated Other Comprehensive Loss (Details) $ in Thousands	9 Months Ended
	Jan. 31, 2021USD ($)
Accumulated other comprehensive (loss) income
Balance	$ 633,981
Balance	761,014
Other comprehensive loss on derivative instruments before reclassification, tax	200
Reclassification of (decrease) increase in fair value financial instruments from Accumulated other comprehensive income (loss)
Amount expected to be reclassified to earnings during next twelve months	(2,100)
Accumulated Other Comprehensive Loss
Accumulated other comprehensive (loss) income
Balance	(65,082)
Other comprehensive income (loss) before reclassification	39,050
Reclassification to earnings from accumulated other comprehensive loss	6,540
Balance	(19,492)
Foreign Currency Translation
Accumulated other comprehensive (loss) income
Balance	(40,577)
Other comprehensive income (loss) before reclassification	39,813
Balance	(764)
Derivative Financial Instruments
Accumulated other comprehensive (loss) income
Balance	(24,505)
Other comprehensive income (loss) before reclassification	(763)
Reclassification to earnings from accumulated other comprehensive loss	6,540
Balance	$ (18,728)

Equity-Based Compensation - Sto

Equity-Based Compensation - Stock Option Activity (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Jan. 31, 2021	Jan. 31, 2020	Jan. 31, 2021	Jan. 31, 2020	Apr. 30, 2020
Other disclosures
Equity-based compensation	$ 1,877	$ 1,465	$ 6,734	$ 5,175
Selling, general and administrative expenses
Other disclosures
Equity-based compensation			$ 6,300	4,800
Stock Options
Number of Options
Outstanding, beginning of the period (in shares)			1,487
Options granted (in shares)			321
Options exercised (in shares)			(195)
Options forfeited (in shares)			(48)
Outstanding, end of the period (in shares)	1,565		1,565		1,487
Exercisable at end of period (in shares)	948		948
Vested and expected to vest at end of period (in shares)	1,558		1,558
Weighted Average Exercise Price
Outstanding, beginning of period (in dollars per share)			$ 18.85
Options granted (in dollars per share)			23.43
Options exercised (in dollars per share)			17.53
Options forfeited (in dollars per share)			25.97
Outstanding, end of the period (in dollars per share)	$ 19.73		19.73		$ 18.85
Exercisable at end of period (in dollars per share)	17.65		17.65
Vested and expected to vest at end of period (in dollars per share)	$ 19.72		$ 19.72
Other disclosures
Weighted Average Remaining Contractual Life, Outstanding (in years)			6 years 6 months		6 years 4 months 24 days
Weighted Average Remaining Contractual Life, Exercisable at end of period (in years)			4 years 10 months 24 days
Weighted Average Remaining Contractual Life, Vested and expected to vest at end of period (in years)			6 years 6 months
Aggregate Intrinsic Value, Outstanding	$ 14,933		$ 14,933		$ 3,895
Aggregate Intrinsic Value, Exercisable at end of period	11,176		11,176
Aggregate Intrinsic Value, Vested and expected to vest at end of period	14,895		14,895
Intrinsic value of options exercised			2,500	$ 9,400
Unrecognized compensation cost	$ 4,600		$ 4,600
Weighted-average period for recognition of unrecognized compensation expense (in years)			2 years

Equity-Based Compensation - Bla

Equity-Based Compensation - Black Scholes Options - Pricing Model (Details) - Stock Options - $ / shares	9 Months Ended
	Jan. 31, 2021	Jan. 31, 2020
Stock options
Volatility (as a percent)	51.28%	49.86%
Expected life (years)	6 years	6 years
Risk-free interest rate (as a percent)	0.30%	1.97%
Dividend yield (as a percent)	0.00%	0.00%
Grant date fair value (in dollars per share)	$ 11.13	$ 10.59

Equity-Based Compensation - Res

Equity-Based Compensation - Restricted Stock Units (Details) - Restricted stock units $ / shares in Units, shares in Thousands, $ in Millions	9 Months Ended
	Jan. 31, 2021USD ($)$ / sharesshares
Number of Restricted Stock Units
Outstanding, beginning of the period (in shares) | shares	286
Granted (in shares) | shares	214
Vested (in shares) | shares	(110)
Forfeited (in shares) | shares	(28)
Outstanding, end of the period (in shares) | shares	362
Weighted Average Exercise Price
Outstanding, beginning of period (in dollars per share) | $ / shares	$ 22.71
Granted (in dollars per share) | $ / shares	23.48
Vested (in dollars per share) | $ / shares	23.21
Forfeited (in dollars per share) | $ / shares	23.93
Outstanding, end of the period (in dollars per share) | $ / shares	$ 22.92
Unrecognized compensation cost | $	$ 5.2
Weighted-average period for recognition of unrecognized compensation expense (in years)	1 year 9 months 18 days

Equity-Based Compensation - Emp

Equity-Based Compensation - Employee Stock Purchase Plan (Details) - USD ($) $ / shares in Units, $ in Thousands, shares in Millions	3 Months Ended		9 Months Ended
	Jan. 31, 2021	Jan. 31, 2020	Jan. 31, 2021	Jan. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	$ 1,877	$ 1,465	$ 6,734	$ 5,175
ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of common stock price based on closing price at the beginning or end of the last day of the purchase period			90.00%
Purchase period			6 months
Number of shares purchased under ESPP			0.1
Average price per share	$ 21.78		$ 21.78
Share-based compensation expense			$ 400	$ 400

Stock Appreciation Rights, De_3

Stock Appreciation Rights, Deferred Compensation and Redeemable Noncontrolling Interests (Details) - USD ($) $ in Thousands	9 Months Ended
	Jan. 31, 2021	Jan. 31, 2020	Apr. 30, 2020
Selling, general and administrative expenses
Equity based compensation arrangements
Expense related to equity based compensation arrangements	$ 3,600	$ 1,300
Stock Appreciation Rights
Equity based compensation arrangements
Award liability as of beginning of period	24,205
Amounts redeemed	(583)
Change in fair value	2,552
Award liability as of end of period	26,174
Award liability, Classified as current	1,200		$ 624
Award liability, Classified as long-term	$ 24,974		23,581
Settlement period	5 years
Deferred Compensation
Equity based compensation arrangements
Award liability as of beginning of period	$ 1,660
Change in fair value	177
Award liability as of end of period	1,837
Award liability, Classified as long-term	$ 1,837		1,660
Settlement period	5 years
Redeemable Noncontrolling Interests
Equity based compensation arrangements
Award liability as of beginning of period	$ 8,300
Change in fair value	885
Award liability as of end of period	9,185
Award liability, Classified as long-term	$ 9,185		$ 8,300
Settlement period	5 years

Fair Value Measurements (Detail

Fair Value Measurements (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Jan. 31, 2021	Jan. 31, 2021	Jan. 31, 2020	Apr. 30, 2020	Feb. 28, 2019
Fair Value Measurements
Impairment charges			$ 1,000
Interest rate swap agreements
Fair Value Measurements
Interest rate swap gains (losses)	$ (2,200)	$ (6,500)
Expected amount of pre-tax net losses will be reclassified from accumulated other comprehensive income (loss) into earnings during the next twelve months		(11,900)
Interest rate swap agreements | Fair Value, Measurements, Recurring | Level 2
Fair Value Measurements
Derivative liabilities	24,566	24,566		$ 32,218
Interest rate swap agreements | Term Loan Facility
Fair Value Measurements
Notional amount					$ 500,000
Interest rate swap agreements | LIBOR | Term Loan Facility
Fair Value Measurements
Fixed interest rate					2.46%
Other accrued expenses and current liabilities | Interest rate swap agreements
Fair Value Measurements
Derivative liabilities	11,900	11,900
Other liabilities | Interest rate swap agreements
Fair Value Measurements
Derivative liabilities	$ 12,600	$ 12,600

Transactions With Related Par_2

Transactions With Related Parties - Purchased Inventories (Details) - Southern Wall Products, Inc. - Inventory purchases - USD ($) $ in Millions	3 Months Ended	9 Months Ended
	Jan. 31, 2020	Jan. 31, 2021	Jan. 31, 2020	Apr. 30, 2020
Transactions with related parties
Purchases from related party	$ 3.2	$ 7.3	$ 10.5
Accounts payable
Transactions with related parties
Due to SWP				$ 1.2

Commitments and Contingencies (

Commitments and Contingencies (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Jan. 31, 2021	Jan. 31, 2021
Commitments and Contingencies
Gain on legal settlement	$ 1,382	$ 1,382

Segments (Details)

Segments (Details)	9 Months Ended	12 Months Ended
	Jan. 31, 2021segmentdivision	Apr. 30, 2020segment
Segments
Number of operating segments | segment	8	7
Number of reportable segments | segment	1
Number of geographic divisions | division	8
Number of operating segment, divisions | division	2

Segments - Net Sales, Adjusted

Segments - Net Sales, Adjusted EBITDA and Certain Other Measures (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jan. 31, 2021	Jan. 31, 2020	Jan. 31, 2021	Jan. 31, 2020
Segment information
Net sales	$ 751,191	$ 761,352	$ 2,366,620	$ 2,470,457
Gross Profit	243,324	253,473	768,853	811,620
Depreciation and Amortization	25,562	29,422	79,904	88,215
Adjusted EBITDA	62,587	62,697	228,163	236,190
Geographic divisions
Segment information
Net sales	741,885	754,916	2,341,430	2,449,926
Gross Profit	240,536	251,086	760,908	804,340
Depreciation and Amortization	24,942	28,791	78,507	86,747
Adjusted EBITDA	61,916	62,169	226,588	234,422
Other.
Segment information
Net sales	9,306	6,436	25,190	20,531
Gross Profit	2,788	2,387	7,945	7,280
Depreciation and Amortization	92	56	274	164
Adjusted EBITDA	671	528	1,575	1,768
Corporate
Segment information
Depreciation and Amortization	$ 528	$ 575	$ 1,123	$ 1,304

Segments - Reconciliation of Ne

Segments - Reconciliation of Net Income to Adjusted EBITDA (Details) - USD ($) $ in Thousands	3 Months Ended						9 Months Ended
	Jan. 31, 2021	Oct. 31, 2020	Jul. 31, 2020	Jan. 31, 2020	Oct. 31, 2019	Jul. 31, 2019	Jan. 31, 2021	Jan. 31, 2020
Segments
Net income	$ 16,126	$ 28,469	$ 27,219	$ 10,879	$ 29,138	$ 24,820	$ 71,814	$ 64,837
Interest expense	13,454			16,474			41,060	52,310
Write-off of debt discount and deferred financing fees								707
Interest income	(6)			(8)			(57)	(26)
Provision for income taxes	5,709			2,816			23,590	18,333
Depreciation expense	11,371			12,930			36,908	37,944
Amortization expense	14,191			16,492			42,996	50,271
Stock appreciation expense	1,446			(347)			2,552	980
Redeemable noncontrolling interests	624			(318)			1,062	326
Equity-based compensation	1,877			1,465			6,734	5,175
Severance and other permitted costs	(83)			1,700			2,626	3,648
Transaction costs (acquisitions and other)	664			434			789	1,733
Gain on disposal and impairment of assets	(1,404)			(130)			(529)	(872)
Effects of fair value adjustments to inventory				310				461
Gain on legal settlement	(1,382)						(1,382)
Secondary public offering costs								363
Adjusted EBITDA	$ 62,587			$ 62,697			$ 228,163	$ 236,190

Segments - Net Sales by Main Pr

Segments - Net Sales by Main Product Lines (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jan. 31, 2021	Jan. 31, 2020	Jan. 31, 2021	Jan. 31, 2020
Revenue from external customers
Total net sales	$ 751,191	$ 761,352	$ 2,366,620	$ 2,470,457
Wallboard
Revenue from external customers
Total net sales	311,122	314,391	969,634	1,006,604
Ceilings
Revenue from external customers
Total net sales	101,909	112,768	326,904	364,685
Steel framing
Revenue from external customers
Total net sales	103,956	118,823	325,736	386,811
Other products
Revenue from external customers
Total net sales	$ 234,204	$ 215,370	$ 744,346	$ 712,357

Segments - Net sales by major g

Segments - Net sales by major geographic area (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jan. 31, 2021	Jan. 31, 2020	Jan. 31, 2021	Jan. 31, 2020
Revenues from External Customers and Long-Lived Assets [Line Items]
Total net sales	$ 751,191	$ 761,352	$ 2,366,620	$ 2,470,457
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Total net sales	637,568	661,491	2,001,020	2,136,968
Canada
Revenues from External Customers and Long-Lived Assets [Line Items]
Total net sales	$ 113,623	$ 99,861	$ 365,600	$ 333,489

Segments - Property and equipme

Segments - Property and equipment, net, by major geographic area (Details) - USD ($) $ in Thousands	Jan. 31, 2021	Apr. 30, 2020
Revenues from External Customers and Long-Lived Assets [Line Items]
Property and equipment, net	$ 305,144	$ 305,467
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Property and equipment, net	268,826	270,855
Canada
Revenues from External Customers and Long-Lived Assets [Line Items]
Property and equipment, net	$ 36,318	$ 34,612

Earnings Per Common Share (Deta

Earnings Per Common Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands		3 Months Ended						9 Months Ended
		Jan. 31, 2021	Oct. 31, 2020	Jul. 31, 2020	Jan. 31, 2020	Oct. 31, 2019	Jul. 31, 2019	Jan. 31, 2021	Jan. 31, 2020
Computation of basic and diluted earnings per share of common stock
Net income		$ 16,126	$ 28,469	$ 27,219	$ 10,879	$ 29,138	$ 24,820	$ 71,814	$ 64,837
Less: Net income allocated to participating securities									273
Net income attributable to common stockholders		$ 16,126			$ 10,879			$ 71,814	$ 64,564
Basic earnings per common share:
Basic weighted average common shares outstanding (in shares)		42,726			42,223			42,691	41,663
Basic earnings per common share (in dollars per share)	[1]	$ 0.38			$ 0.26			$ 1.68	$ 1.55
Diluted earnings per common share:
Basic weighted average common shares outstanding (in shares)		42,726			42,223			42,691	41,663
Add: Common Stock Equivalents		635			726			493	738
Diluted weighted average common shares outstanding (in shares)		43,361			42,949			43,184	42,401
Diluted earnings per common share (in dollars per share)	[1]	$ 0.37			$ 0.25			$ 1.66	$ 1.52
Shares were not included in the calculation of Diluted loss per common share
Anti-dilutive shares		300						400
[1]	See Note 15 for detailed calculations .

Subsequent Events (Details)

Subsequent Events (Details) - Subsequent Events. - D.L. Building Materials, Inc $ in Millions, $ in Millions	Feb. 01, 2021USD ($)item	Feb. 01, 2021CAD ($)item
Subsequent Events
Aggregate purchase price	$ 39.1	$ 50
Number Of Locations	2	2