Griffon (GFF) 10-K 13 Nov 20 2020 FY Annual report Financial data

Cover

Cover - USD ($)	12 Months Ended
	Sep. 30, 2020	Oct. 31, 2020	Mar. 31, 2020
Cover [Abstract]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Sep. 30, 2020
Document Transition Report	false
Entity File Number	1-06620
Entity Registrant Name	GRIFFON CORP
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	11-1893410
Entity Address, Address Line One	712 Fifth Ave, 18th Floor
Entity Address, City or Town	New York
Entity Address, State or Province	NY
Entity Address, Postal Zip Code	10019
City Area Code	212
Local Phone Number	957-5000
Title of 12(b) Security	Common Stock, $0.25 par value
Trading Symbol	GFF
Security Exchange Name	NYSE
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
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
ICFR Auditor Attestation Flag	true
Entity Shell Company	false
Entity Public Float			$ 527,000,000
Entity Common Stock, Shares Outstanding		56,124,504
Documents Incorporated by Reference	Part III — (Items 10, 11, 12, 13 and 14). Registrant’s definitive proxy statement to be filed pursuant to Regulation 14A of the Securities Exchange Act of 1934.
Current Fiscal Year End Date	--09-30
Amendment Flag	false
Entity Central Index Key	0000050725
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	FY

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Sep. 30, 2020	Sep. 30, 2019
CURRENT ASSETS
Cash and equivalents	$ 218,089	$ 72,377
Accounts receivable, net of allowances of $17,758 and $7,881	348,124	264,450
Contract assets, net of progress payments of $24,175 and $11,259	84,426	105,111
Inventories	413,825	442,121
Prepaid and other current assets	46,897	40,799
Assets of discontinued operations	2,091	321
Total Current Assets	1,113,452	925,179
PROPERTY, PLANT AND EQUIPMENT, net	343,964
PROPERTY, PLANT AND EQUIPMENT, net		337,326
OPERATING LEASE RIGHT-OF-USE ASSETS	161,627
GOODWILL	442,643	437,067
INTANGIBLE ASSETS, net	355,028	356,639
OTHER ASSETS	32,897	15,840
ASSETS OF DISCONTINUED OPERATIONS	6,406	2,888
Total Assets	2,456,017	2,074,939
CURRENT LIABILITIES
Notes payable and current portion of long-term debt	9,922	10,525
Accounts payable	232,107	250,576
Accrued liabilities	171,572	124,665
Current portion of operating lease liabilities	31,848
Liabilities of discontinued operations	3,797	4,333
Total Current Liabilities	449,246	390,099
LONG-TERM DEBT, net	1,037,042	1,093,749
LONG-TERM OPERATING LEASE LIABILITIES	136,054
OTHER LIABILITIES	126,510	109,997
LIABILITIES OF DISCONTINUED OPERATIONS	7,014	3,331
Total Liabilities	1,755,866	1,597,176
COMMITMENTS AND CONTINGENCIES - See Note 14
SHAREHOLDERS’ EQUITY
Preferred stock, par value $0.25 per share, authorized 3,000 shares, no shares issued	0	0
Common stock, par value $0.25 per share, authorized 85,000 shares, issued shares of 83,739 and 82,775, respectively.	20,935	20,694
Capital in excess of par value	583,008	519,017
Retained earnings	607,518	568,516
Treasury shares, at cost, 27,610 common shares and 35,969 common shares	(413,493)	(536,308)
Accumulated other comprehensive loss	(72,092)	(65,916)
Deferred compensation	(25,725)	(28,240)
Total Shareholders’ Equity	700,151	477,763
Total Liabilities and Shareholders’ Equity	$ 2,456,017	$ 2,074,939

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parentheticals) - USD ($) $ in Thousands	Sep. 30, 2020	Sep. 30, 2019
Statement of Financial Position [Abstract]
Accounts receivable, net allowances	$ 17,758	$ 7,881
Contract costs, net of progress payments	$ 24,175	$ 11,259
Preferred stock, par value (in dollars per share)	$ 0.25	$ 0.25
Preferred stock, share authorized (in shares)	3,000,000	3,000,000
Preferred stock, shares issued (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.25	$ 0.25
Common stock, share authorized (in shares)	85,000,000	85,000,000
Common stock, shares issued (in shares)	83,739,000	82,775,000
Treasury shares (in shares)	27,610,000	35,969,000

CONSOLIDATED STATEMENTS OF OPER

CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Income Statement [Abstract]
Revenue	$ 2,407,522	$ 2,209,289	$ 1,977,918
Cost of goods and services	1,766,096	1,625,815	1,466,600
Gross profit	641,426	583,474	511,318
Selling, general and administrative expenses	486,398	447,163	418,517
Income from continuing operations	155,028	136,311	92,801
Other income (expense)
Interest expense	(66,544)	(68,066)	(65,568)
Interest income	753	806	1,697
Loss from debt extinguishment	(7,925)	0	0
Other, net	1,445	3,127	4,880
Total other income (expense)	(72,271)	(64,133)	(58,991)
Income before taxes from continuing operations	82,757	72,178	33,810
Provision for income taxes	29,328	26,556	555
Income (loss) from continuing operations	53,429	45,622	33,255
Discontinued operations:
Income (loss) from operations of discontinued businesses	0	(11,050)	119,981
Provision for income taxes	0	(2,715)	27,558
Income (loss) from discontinued operations	0	(8,335)	92,423
Net income	$ 53,429	$ 37,287	$ 125,678
Income from continuing operations (in usd per share)	$ 1.25	$ 1.11	$ 0.81
Income from discontinued operations (in usd per share)	0	(0.20)	2.25
Basic earnings per common share (in usd per share)	$ 1.25	$ 0.91	$ 3.06
Weighted-average shares outstanding (in shares)	42,588	40,934	41,005
Income from continuing operations (in usd per share)	$ 1.19	$ 1.06	$ 0.78
Income from discontinued operations (in usd per share)	0	(0.20)	2.18
Diluted earnings per common share (in usd per share)	$ 1.19	$ 0.87	$ 2.96
Weighted-average shares outstanding (in shares)	45,015	42,888	42,422
Other comprehensive income (loss), net of taxes:
Foreign currency translation adjustments	$ 5,601	$ (8,460)	$ 9,403
Pension and other post retirement plans	(11,784)	(23,055)	16,381
Gain (loss) on cash flow hedge	7	(289)	585
Total other comprehensive income (loss), net of taxes	(6,176)	(31,804)	26,369
Comprehensive income	$ 47,253	$ 5,483	$ 152,047

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
CASH FLOWS FROM OPERATING ACTIVITIES - CONTINUING OPERATIONS:
Net income	$ 53,429	$ 37,287	$ 125,678
Net (income) loss from discontinued operations	0	8,335	(92,423)
Adjustments to reconcile net income to net cash provided by operating activities of continuing operations:
Depreciation and amortization	62,409	61,848	55,803
Stock-based compensation	17,580	15,914	19,610
Asset impairment charges - restructuring	4,692	0	0
Provision for losses on accounts receivable	1,332	535	96
Amortization of deferred financing costs and debt discounts	3,661	5,393	5,219
Loss from debt extinguishment	7,925	0	0
Deferred income tax	2,095	(2,222)	(17,633)
(Gain)/ loss on sale/disposal of assets and investments	(287)	(179)	290
Change in assets and liabilities, net of assets and liabilities acquired:
(Increase) decrease in accounts receivable and contract assets	(62,366)	8,279	2,681
(Increase) decrease in inventories	34,080	(24,938)	(52,122)
Increase in prepaid and other assets	(13,582)	(4,285)	(2,285)
Increase in accounts payable, accrued liabilities and income taxes payable	25,044	7,638	11,078
Other changes, net	1,017	353	2,200
Net cash provided by operating activities - continuing operations	137,029	113,958	58,192
CASH FLOWS FROM INVESTING ACTIVITIES - CONTINUING OPERATIONS:
Acquisition of property, plant and equipment	(48,998)	(45,361)	(50,138)
Acquired business, net of cash acquired	(10,531)	(9,219)	(430,932)
Investment purchases	(130)	(149)	0
Proceeds (payments) from sale of business	0	(9,500)	474,727
Insurance proceeds (payments)	0	(10,604)	8,254
Proceeds from sale of property, plant and equipment	352	280	663
Net cash provided by (used in) investing activities - continuing operations	(59,307)	(74,553)	2,574
CASH FLOWS FROM FINANCING ACTIVITIES - CONTINUING OPERATIONS:
Proceeds from issuance of common stock	178,165	0	0
Dividends paid	(14,529)	(13,676)	(49,797)
Purchase of shares for treasury	(7,479)	(1,478)	(45,605)
Proceeds from long-term debt	1,240,080	201,748	443,058
Payments of long-term debt	(1,308,915)	(218,248)	(300,993)
Change in short-term borrowings	0	(366)	144
Financing costs	(17,384)	(1,090)	(7,793)
Contingent consideration for acquired businesses	(1,733)	(1,686)	0
Other, net	(15)	(180)	51
Net cash provided by (used) in financing activities - continuing operations	68,190	(34,976)	39,065
CASH FLOWS FROM DISCONTINUED OPERATIONS:
Net cash used in operating activities	(3,021)	(2,123)	(45,624)
Net cash provided by (used in) investing activities	444	0	(10,762)
Net cash used in financing activities	0	0	(22,541)
Net cash used in discontinued operations	(2,577)	(2,123)	(78,927)
Effect of exchange rate changes on cash and equivalents	2,377	313	1,173
NET INCREASE IN CASH AND EQUIVALENTS	145,712	2,619	22,077
CASH AND EQUIVALENTS AT BEGINNING OF PERIOD	72,377	69,758	47,681
CASH AND EQUIVALENTS AT END OF PERIOD	218,089	72,377	69,758
Supplemental Disclosure of Cash Flow Information:
Cash paid for interest	63,139	63,334	59,793
Cash paid for taxes	$ 21,016	$ 25,339	$ 32,140

CONSOLIDATED STATEMENTS OF SHAR

CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY - USD ($) $ in Thousands	Total	COMMON STOCK	CAPITAL IN EXCESS OF PAR VALUE	RETAINED EARNINGS	TREASURY SHARES	ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS)	DEFERRED COMPENSATION	Series of Individually Immaterial Business Acquisitions	Series of Individually Immaterial Business AcquisitionsCAPITAL IN EXCESS OF PAR VALUE	Cumulative Effect, Period of Adoption, Adjustment	Cumulative Effect, Period of Adoption, AdjustmentRETAINED EARNINGS
Balance (in shares) at Sep. 30, 2017		80,663,000			33,557,000
Balance at Sep. 30, 2017	$ 398,808	$ 20,166	$ 487,077	$ 480,347	$ (489,225)	$ (60,481)	$ (39,076)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	125,678			125,678
Dividends	(55,502)			(55,502)
Shares withheld on employee taxes on vested equity awards (in shares)					200,000
Shares withheld on employee taxes on vested equity awards	(4,495)				$ (4,495)
Amortization of deferred compensation	8,110						8,110
Common stock acquired (in shares)					2,089,000
Common stock acquired	(41,110)				$ (41,110)
Equity awards granted, net (in shares)		857,000
Equity awards granted, net		$ 214	(214)
ESOP allocation of common stock	4,756		4,756
Stock-based compensation	10,078		10,078					$ 1,699	$ 1,699
Other comprehensive loss, net of tax	26,369					26,369
Balance (in shares) at Sep. 30, 2018		81,520,000			35,846,000
Balance at Sep. 30, 2018	474,391	$ 20,380	503,396	550,523	$ (534,830)	(34,112)	(30,966)			$ (5,618)	$ (5,618)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	37,287			37,287
Dividends	(13,676)			(13,676)
Shares withheld on employee taxes on vested equity awards (in shares)					86,000
Shares withheld on employee taxes on vested equity awards	(1,106)				$ (1,106)
Amortization of deferred compensation	2,726						2,726
Common stock acquired (in shares)					37,000
Common stock acquired	(372)				$ (372)
Equity awards granted, net (in shares)		1,255,000
Equity awards granted, net		$ 314	(314)
ESOP allocation of common stock	1,512		1,512
Stock-based compensation	13,285		13,285					1,138	1,138
Other comprehensive loss, net of tax	(31,804)					(31,804)
Balance (in shares) at Sep. 30, 2019		82,775,000			35,969,000
Balance at Sep. 30, 2019	477,763	$ 20,694	$ 519,017	568,516	$ (536,308)	(65,916)	(28,240)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	53,429			53,429
Dividends	$ (14,427)			(14,427)
Shares withheld on employee taxes on vested equity awards (in shares)	340,775				341,000
Shares withheld on employee taxes on vested equity awards	$ (7,479)				$ (7,479)
Amortization of deferred compensation	2,515						2,515
Common stock issued (in shares)			46,900,000		(8,700,000)
Common stock issued	177,194				$ 130,294
Equity awards granted, net (in shares)		964,000
Equity awards granted, net		$ 241	$ (241)
ESOP allocation of common stock	1,985		1,985
Stock-based compensation	14,702		14,702					$ 645	$ 645
Other comprehensive loss, net of tax	(6,176)					(6,176)
Balance (in shares) at Sep. 30, 2020		83,739,000			27,610,000
Balance at Sep. 30, 2020	$ 700,151	$ 20,935	$ 583,008	$ 607,518	$ (413,493)	$ (72,092)	$ (25,725)

DESCRIPTION OF BUSINESS AND SUM

DESCRIPTION OF BUSINESS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	12 Months Ended
	Sep. 30, 2020
Accounting Policies [Abstract]
DESCRIPTION OF BUSINESS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	DESCRIPTION OF BUSINESS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Description of business Griffon Corporation (the “Company”, “Griffon”, "we" or "us") is a diversified management and holding company that conducts business through wholly-owned subsidiaries. Griffon oversees the operations of its subsidiaries, allocates resources among them and manages their capital structures. Griffon provides direction and assistance to its subsidiaries in connection with acquisition and growth opportunities as well as in connection with divestitures. In order to further diversify, Griffon also seeks out, evaluates and, when appropriate, will acquire additional businesses that offer potentially attractive returns on capital. The Company was founded in 1959, is a Delaware corporation headquartered in New York, N.Y. and is listed on the New York Stock Exchange (NYSE:GFF). In August 2020 Griffon Corporation completed the public offering of 8,700,000 shares of our common stock for total net proceeds of $178,165 (the "Public Offering"). The Company used a portion of the net proceeds to repay outstanding borrowings under its Credit Agreement. The Company intends to use the remainder of the proceeds for general corporate purposes, including to expand its current business through acquisitions of, or investments in, other businesses or products. On February 19, 2020, Griffon issued, at par, $850,000 of 5.75% Senior Notes due in 2028 (the “2028 Senior Notes”) and on June 8, 2020 Griffon issued an additional $150,000 of notes under the same indenture, at 100.25% of par (collectively, the "2028 Senior Notes"). Proceeds from the 2028 Senior Notes were used to redeem the $1,000,000 of 5.25% Senior Notes due 2022 (the "2022 Senior Notes"). In January 2020, Griffon amended its credit agreement to increase the total amount available for borrowing from $350,000 to $400,000 , extend its maturity date from March 22, 2021 to March 22, 2025 and modify certain other provisions of the facility (the "Credit Agreement"). In November 2019, Griffon announced the development of a next-generation business platform for CPP to enhance the growth, efficiency, and competitiveness of its U.S. operations, and on November 12, 2020, Griffon announced that CPP is broadening this strategic initiative to include additional North American facilities, the AMES UK and Australia businesses, and a manufacturing facility in China. The expanded focus of this initiative leverages the same three key development areas being executed within our U.S. operations. First, multiple independent information systems will be unified into a single data and analytics platform, which will serve the whole AMES global enterprise. Second, certain AMES global operations will be consolidated to optimize facilities footprint and talent. Third, strategic investments in automation and facilities expansion will be made to increase the efficiency of our manufacturing and fulfillment operations, and support e-commerce growth. The cost to implement this new business platform, over the duration of the project, will include one-time charges of approximately $65,000 (increased from $35,000 ) and capital investments of approximately $65,000 (increased from $40,000 ). The one-time charges are comprised of $46,000 of cash charges, which includes $26,000 of personnel-related costs such as training, severance, and duplicate personnel costs as well as $20,000 of facility and lease exit costs. The remaining $19,000 of charges are non-cash and are primarily related to asset write-downs. In March 2020, the World Health Organization declared the outbreak of COVID-19 a pandemic, which continues to spread throughout the U.S. and the world. While Griffon has not incurred significant disruptions to its manufacturing or supply chain thus far, the Company continues to actively monitor the situation and evaluate the nature and extent of the impact of the COVID-19 pandemic on its businesses, consolidated results of operations and financial condition. Griffon places a high priority on the health and safety of its employees, customers and their families, and has implemented a variety of new policies and procedures, including additional cleaning, social distancing, staggered shifts and prohibiting or significantly restricting on-site visitors, to minimize the risk to its employees of contracting COVID-19. Although many U.S. states lifted initial executive orders issued earlier in the year requiring all workers to remain at home unless their work is critical, essential, or life-sustaining, some states and localities have recently put in place new restrictions regarding the operation of many types of businesses, or have tightened up restrictions already in place, in response to the recent worsening of the COVID-19 outbreak. As of the date of this filing, all of Griffon's facilities are fully operational and the Company’s supply chains have not experienced significant disruption. Griffon manufactures a substantial majority of its products that it sells, with the majority of manufacturing activities conducted in the United States. As a result, Griffon has been able to mitigate the adverse impact of the COVID-19 pandemic on the global supply chain. While Griffon is unable to determine or predict the nature, duration or scope of the overall impact the COVID-19 pandemic will have on its businesses, results of operations, liquidity or capital resources, Griffon will continue to actively monitor the situation and may take further actions that impact its operations as may be required by federal, state or local authorities or that it determines is in the best interests of its employees, customers, suppliers and shareholders. For additional factors to consider, see Part 1, Item 1A, “Risk Factors” in this Form 10-K. Griffon currently conducts its operations through three reportable segments: • Consumer and Professional Products ("CPP") conducts its operations through The AMES Companies, Inc. (“AMES”). Founded in 1774, AMES is the leading North American manufacturer and a global provider of branded consumer and professional tools and products for home storage and organization, landscaping, and enhancing outdoor lifestyles. CPP sells products globally through a portfolio of leading brands including True Temper, AMES, and ClosetMaid. • Home and Building Products ("HBP") conducts its operations through Clopay. Founded in 1964, Clopay is the largest manufacturer and marketer of garage doors and rolling steel doors in North America. Residential and commercial sectional garage doors are sold through professional dealers and leading home center retail chains throughout North America under the brands Clopay, Ideal, and Holmes. Rolling steel door and grille products designed for commercial, industrial, institutional, and retail use are sold under the CornellCookson brand. • Defense Electronics ("DE") conducts its operations through Telephonics Corporation ("Telephonics"), founded in 1933, a globally recognized leading provider of highly sophisticated intelligence, surveillance and communications solutions for defense, aerospace and commercial customers. Consolidation The consolidated financial statements include the accounts of Griffon and all subsidiaries. Intercompany accounts and transactions have been eliminated in consolidation. The results of operations of acquired businesses are included from the dates of acquisitions. Earnings per share Due to rounding, the sum of earnings per share may not equal earnings per share of Net income. Discontinued operations On November 16, 2017, Griffon announced it entered into a definitive agreement to sell Plastics and on February 6, 2018, completed the sale to Berry for approximately $465,000 , net of certain post-closing adjustments. As a result, Griffon classified the results of operations of the Plastics business as discontinued operations in the Consolidated Statements of Operations for all periods presented and classified the related assets and liabilities associated with the discontinued operations in the consolidated balance sheets. All results and information presented exclude Plastics unless otherwise noted. See Note 7, Discontinued Operations. Reclassifications Certain amounts in prior years have been reclassified to conform to the current year presentation. Use of estimates The preparation of financial statements in conformity with accounting principles generally accepted in the United States requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosure of contingent assets and liabilities at the date of the financial statements, and the reported amounts of revenue and expenses during the reporting periods. These estimates may be adjusted due to changes in economic, industry or customer financial conditions, as well as changes in technology or demand. Significant estimates include allowances for doubtful accounts receivable and returns, net realizable value of inventories, restructuring reserves, valuation of goodwill and intangible assets, sales, profits and loss recognition for performance obligations satisfied over time, assumptions associated with pension benefit obligations and income or expenses, useful lives associated with depreciation and amortization of intangible and fixed assets, warranty reserves, sales incentive accruals, assumption associated with stock based compensation valuation, income taxes and tax valuation reserves, environmental reserves, legal reserves, insurance reserves, the valuation of assets and liabilities of discontinued operations, assumptions associated with valuation of acquired assets and assumed liabilities of acquired companies and the accompanying disclosures. These estimates are based on management’s best knowledge of current events and actions Griffon may undertake in the future. Actual results may ultimately differ from these estimates. Cash and equivalents Griffon considers all highly liquid investments purchased with an initial maturity of three months or less to be cash equivalents. Cash equivalents primarily consist of overnight commercial paper, highly-rated liquid money market funds backed by U.S. Treasury securities and U.S. Agency securities, as well as insured bank deposits. Griffon had cash in non-U.S. bank accounts of approximately $55,000 and $34,200 at September 30, 2020 and 2019, respectively. Substantially all U.S. cash and equivalents are in excess of FDIC insured limits. Griffon regularly evaluates the financial stability of all institutions and funds that hold its cash and equivalents. Fair value of financial instruments The carrying values of cash and cash equivalents, accounts receivable, accounts and notes payable and revolving credit debt approximate fair value due to either the short-term nature of such instruments or the fact that the interest rate of the revolving credit debt is based upon current market rates. The fair value hierarchy, as outlined in the applicable accounting guidance, establishes a fair value hierarchy that requires the Company to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. A financial instrument’s categorization within the hierarchy is based on the lowest level of input that is significant to the fair value measurement. The accounting guidance establishes three levels of inputs that may be used to measure fair value, as follows: • Level 1 inputs are measured and recorded at fair value based upon quoted prices in active markets for identical assets. • Level 2 inputs include inputs other than Level 1 that are observable, either directly or indirectly, such as quoted prices in active markets for similar assets and liabilities, quoted prices for identical or similar assets or liabilities in markets that are not active, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of assets or liabilities. • Level 3 inputs are unobservable inputs in which little or no market data exists, therefore requiring an entity to develop its own assumptions. The fair value of Griffon’s 2028 Senior Notes approximated $1,040,000 , on September 30, 2020 . Fair values were based upon quoted market prices (level 1 inputs). Insurance contracts with a value of $3,436 at September 30, 2020 are measured and recorded at fair value based upon quoted prices in active markets for similar assets (level 2 inputs) and are included in Other current assets on the consolidated balance sheet. Items Measured at Fair Value on a Recurring Basis At September 30, 2020 and 2019, trading securities, measured at fair value based on quoted prices in active markets for similar assets (level 2 inputs), with a fair value of $1,703 ( $1,000 cost basis) and $1,518 ( $1,000 cost basis), respectively, were included in Prepaid and other current assets on the Consolidated Balance Sheets. In the normal course of business, Griffon’s operations are exposed to the effect of changes in foreign currency exchange rates. To manage these risks, Griffon may enter into various derivative contracts such as foreign currency exchange contracts, including forwards and options. During 2020 and 2019, Griffon entered into several such contracts in order to lock into a foreign currency rate for planned settlements of trade and inter-company liabilities payable in USD. At September 30, 2020 and 2019, Griffon had $32,000 and $14,000 of Australian dollar contracts at a weighted average rate of $1.41 and $1.48 , respectively, which qualified for hedge accounting. These hedges were all deemed effective as cash flow hedges with gains and losses related to changes in fair value deferred and recorded in Other comprehensive income (loss) and Prepaid and other current assets, or Accrued liabilities, until settlement. Upon settlement, gains and losses were recognized in the Consolidated Statements of Operations and Comprehensive Income (Loss) in Cost of goods and services. AOCI included deferred losses of $168 ( $109 , net of tax) and deferred gains of $327 ( $213 , net of tax) at September 30, 2020 and 2019, respectively. Upon settlement, gains (losses) of $(2,163) and $1,361 were recognized in the Consolidated Statements of Operations and Comprehensive Income (Loss) in Cost of goods and services ("COGS") during 2020 and 2019, respectively. Contracts expire in 30 to 146 days . At September 30, 2020 and 2019, Griffon had $7,900 and $3,500 , respectively, of Canadian dollar contracts at a weighted average rate of $1.33 and $1.32 . These contracts, which protect Canadian operations from currency fluctuations for U.S. dollar based purchases, do not qualify for hedge accounting and fair value gains (losses) of $(92) and $14 were recorded in Other assets and to Other income for the outstanding contracts, based on similar contract values (level 2 inputs), for the years ended September 30, 2020 and 2019, respectively. Realized gains of $189 and $68 , were recorded in Other income during 2020 and 2019, respectively. Contracts expire in 30 to 360 days . At September 30, 2020, Griffon had $5,400 of Great Britain Pound contracts at a weighted average rate of $0.77 . These contracts, which protect U.K. operations from currency fluctuations for U.S. dollar based purchases, do not qualify for hedge accounting and fair value gains of $39 were recorded in Other assets and to Other income for the outstanding contracts, based on similar contract values (level 2 inputs), for the years ended September 30, 2020. There were no realized gains or losses recorded for these contracts during the year ended September 30, 2020. Contracts expire in 2 to 208 days . Pension plan assets with a fair value of $147,145 at September 30, 2020 , are measured and recorded at fair value based upon quoted prices in active markets for identical assets (level 1 inputs), quoted market prices for similar assets (level 2 inputs) and fair value assumptions for unobservable inputs in which little or no market data exists (level 3). Non-U.S. currency translation Assets and liabilities of non-U.S. subsidiaries, where the functional currency is not the U.S. dollar, have been translated at year-end exchange rates and profit and loss accounts have been translated using weighted average exchange rates. Adjustments resulting from currency translation have been recorded in the equity section of the balance sheet in AOCI as cumulative translation adjustments. Cumulative translation adjustments were gains (losses) of $5,601 and $(8,460) for 2020 and 2019, respectively. As of September 30, 2020 and 2019, the foreign currency translation components of Accumulated other comprehensive loss were $25,683 and $31,284 , respectively. Assets and liabilities of an entity that are denominated in currencies other than that entity’s functional currency are re-measured into the functional currency using period end exchange rates, or historical rates where applicable to certain balances. Gains and losses arising on remeasurements are recorded within the Consolidated Statement of Operations and Comprehensive Income as a component of Other income (expense). Revenue recognition Effective October 1, 2018, the Company adopted Accounting Standard Codification (“ASC”) Topic 606, Revenue from Contracts with Customers. Our statement of operations for the year ended September 30, 2020 and 2019 and our balance sheet as of September 30, 2020 and 2019 are presented under ASC 606, while our statement of operations for the year ended September 30, 2018 is presented under ASC 605, Revenue Recognition. Under ASC Topic 606, performance obligation is a promise in a contract to transfer a distinct good or service, or a bundle of goods or services, to the customer, and is the unit of accounting under ASC Topic 606. A contract with a customer is an agreement which both parties have approved, that creates enforceable rights and obligations, has commercial substance and with respect to which payment terms are identified and collectability is probable. Once the Company has entered into a contract or purchase order, it is evaluated to identify performance obligations. For each performance obligation, revenue is recognized when control of the promised products is transferred to the customer, or services are satisfied under the contract or purchase order, in an amount that reflects the consideration the Company expects to be entitled to in exchange for those products or services (the transaction price). A contract's transaction price is allocated to each distinct performance obligation and recognized as revenue when each performance obligation is satisfied. A majority of the Company’s contracts have a single performance obligation which represents, in most cases, the product being sold to the customer. To a lesser extent, some contracts include multiple performance obligations such as a product, the related installation, and extended warranty services. These contracts require judgment in determining the number of performance obligations. For contracts with multiple performance obligations, judgment is required to determine whether performance obligations specified in these contacts are distinct and should be accounted for as separate revenue transactions for recognition purposes. In these types of contracts, the Company allocates the total transaction price to each performance obligation in an amount based on the estimated relative standalone selling prices of the promised goods or services underlying each performance obligation. The Company uses an observable price to determine the stand-alone selling price for separate performance obligations or a cost plus margin approach when one is not available. The transaction price includes variable consideration, such as discounts and volume rebates, when it is probable that a significant reversal of revenue recognized will not occur. Variable consideration is determined using either the expected value or the most likely amount of consideration to be received based on historical experience and the specific facts and circumstances at the time of evaluation. Approximately 86% of the Company’s performance obligations are recognized at a point in time related to the manufacture and sale of a broad range of products and components primarily within the CPP and HBP Segments, and revenue is recognized when title, and risk and rewards of ownership, have transferred to the customer, which is generally upon shipment. Approximately 14% of the Company’s performance obligations are recognized over time and relate to prime or subcontractors from contract awards with the U.S. Government, as well as foreign governments and other commercial customers within our DE Segment. Revenue recognized over time are generally accounted for using an input measure to determine progress completed at the end of the period. We believe that cumulative costs incurred to date as a percentage of estimated total contract costs at completion (cost-to-cost method) is an appropriate measure of progress towards satisfaction of performance obligations recognized over time, as it most accurately depicts the progress of our work and transfer of control to our customers. Refer to Note 2 - Revenue for a discussion of our revenue recognition practices for each of our reportable segments. Accounts receivable, allowance for doubtful accounts and concentrations of credit risk Accounts receivable is composed principally of trade accounts receivable, that arise from the sale of goods or services on account, and is stated at historical cost. A substantial portion of Griffon’s trade receivables are from customers within the CPP and HBP businesses, of which the largest customer is Home Depot, whose financial condition is dependent on the construction and related retail sectors of the economy. As a percentage of consolidated accounts receivable, U.S. Government related programs were 9% and Home Depot was 18% . Griffon performs continuing evaluations of the financial condition of its customers, and although Griffon generally does not require collateral, letters of credit may be required from customers in certain circumstances. Trade receivables are recorded at the stated amount, less allowance for doubtful accounts and, when appropriate, for customer program reserves and cash discounts. The allowance represents estimated uncollectible receivables associated with potential customer defaults on contractual obligations (usually due to customers’ potential insolvency). The allowance for doubtful accounts includes amounts for certain customers where a risk of default has been specifically identified, as well as an amount for customer defaults based on a formula when it is determined the risk of some default is probable and estimable, but cannot yet be associated with specific customers. The provision related to the allowance for doubtful accounts is recorded in Selling, general and administrative ("SG&A") expenses. The Company writes-off accounts receivable when they are deemed to be uncollectible. Customer program reserves and cash discounts are netted against accounts receivable when it is customer practice to reduce invoices for these amounts. The amounts netted against accounts receivable in 2020 and 2019 were $27,607 and $17,322 , respectively. All accounts receivable amounts are expected to be collected in less than one year. The Company does not currently have customers or contracts that prescribe specific retainage provisions. Contract assets Contract assets consists of amounts accounted for under the cost-to-cost method of accounting, recoverable costs and accrued profit that cannot yet be invoiced under the terms of certain long-term contracts. Amounts will be invoiced when applicable contract terms, such as the achievement of specified milestones or product delivery, are met. At September 30, 2020 and 2019, approximately $7,500 and $13,100 , respectively, of contract assets were expected to be collected after one year. Inventories Inventories, stated at the lower of cost (first-in, first-out or average) or market, include material, labor and manufacturing overhead costs. Griffon’s businesses typically do not require inventory that is susceptible to becoming obsolete or dated. In general, Telephonics sells products in connection with programs authorized and approved under contracts awarded by the U.S. Government or agencies thereof and in accordance with customer specifications. HBP produces residential and commercial sectional garage doors, commercial rolling steel door and grille products, and CPP produces long-handled tools and landscaping products, and storage and organizational products, both in response to orders from customers of retailers and dealers or based on expected orders, as applicable. Property, plant and equipment Property, plant and equipment includes the historical cost of land, buildings, equipment and significant improvements to existing plant and equipment or, in the case of acquisitions, a fair market value appraisal of such assets completed at the time of acquisition. Expenditures for maintenance, repairs and minor renewals are expensed as incurred. When property or equipment is sold or otherwise disposed of, the related cost and accumulated depreciation is removed from the respective accounts and the gain or loss is recognized. No event or indicator of impairment occurred during the three years ended September 30, 2020 , which would require additional impairment testing of property, plant and equipment. Depreciation expense, which includes amortization of assets under capital leases, was $52,819 , $51,926 and $46,733 in 2020, 2019 and 2018, respectively, and was calculated on a straight-line basis over the estimated useful lives of the assets. Depreciation included in SG&A expenses was $19,656 , $19,026 and $16,306 in 2020, 2019 and 2018, respectively. The remaining components of depreciation, attributable to manufacturing operations, are included in Cost of goods and services. Estimated useful lives for property, plant and equipment are as follows: buildings and building improvements, 25 to 40 years ; machinery and equipment, 2 to 15 years ; and leasehold improvements, over the term of the lease or life of the improvement, whichever is shorter. Capitalized interest costs included in Property, plant and equipment were $2,520 , $2,925 and $2,896 for the years ended September 30, 2020 , 2019 and 2018, respectively. The original cost of fully-depreciated property, plant and equipment remaining in use at September 30, 2020 was approximately $262,255 . Goodwill and indefinite-lived intangibles Griffon has significant intangible and tangible long-lived assets on its balance sheet that includes goodwill and other intangible assets related to acquisitions. Goodwill represents the excess of the cost of net assets acquired in business combinations over the fair value of the identifiable tangible and intangible assets acquired and liabilities assumed in a business combination. We review goodwill and indefinite-lived intangibles for impairment at least annually in the fourth quarter, or more frequently whenever events or circumstances change that would more likely than not reduce the fair value of a reporting unit below the carrying amount. Such events or changes in circumstance include significant deterioration in overall economic conditions, changes in the business climate in which our reporting units operate, a decline in our market capitalization, operating performance indicators, when some portion of a reporting unit is disposed of or classified as held for sale, or when a change in the composition of reporting units occurs for other reasons, such as a change in operating segments. We had three reporting units at September 30, 2020 and 2019, which are our operating segments. We use both qualitative and quantitative approaches when testing goodwill and indefinite-lived intangibles for impairment. When determining the approach to use, we consider the current facts and circumstances of each reporting unit, as well as the excess of each reporting unit’s estimated fair value over its carrying value based on our most recent quantitative assessment. In addition, our qualitative approach evaluates industry and market conditions and various events impacting a reporting unit including, but not limited to, macroeconomic conditions, changes in the business environment in which our reporting units operate and other reporting unit specific events and circumstances. If, based on the qualitative assessment, we determine that it is more likely than not that the fair value of a reporting unit is greater than its carrying value, then a quantitative assessment is not necessary. However, if a quantitative assessment is necessary, we use the income approach methodology of valuation that includes the present value of expected future cash flows. We performed a quantitative annual impairment test as of September 30, 2019, and an interim quantitative impairment test as of March 31, 2020, to assess the impact of the global outbreak of COVID-19, using discounted future cash flows for each reporting unit, which did not result in impairments to goodwill. The more significant assumptions used for the interim impairment test as of March 31, 2020 were a five-year cash flow projection and a 3.0% terminal value to which discount rates between 7.1% and 9% were applied to calculate each unit’s fair value. To substantiate fair values derived from the income approach methodology of valuation, the implied fair value was compared to the marketplace fair value of a comparable industry grouping for reasonableness. Further, the fair values were reconciled to Griffon’s market capitalization. We performed a qualitative assessment as of September 30, 2020, as the estimated fair values of each reporting unit significantly exceeded the carrying value based on our most recent quantitative assessment, which was performed as of March 31, 2020. Our qualitative assessment determined that indicators that the fair value of each reporting unit was less than the carrying value were not present. With respect to indefinite-lived intangibles we performed a quantitative annual impairment test as of September 30, 2019, and an interim quantitative impairment test as of March 31, 2020, to assess the impact of the global outbreak of COVID-19, using a relief from royalty method, which did not result in impairments. We performed a qualitative assessment as of September 30, 2020 considering all the above factors and determined that indefinite-lived intangibles fair values were greater than their book values. Long-lived amortizable intangible assets, such as customer relationships and software, and tangible assets, primarily property, plant and equipment, are amortized over their expected useful lives, which involve significant assumptions and estimates. Long-lived intangible and tangible assets are tested for impairment by comparing estimated future undiscounted cash flows to the carrying value of the asset when an impairment indicator, such as change in business, customer loss or obsolete technology, exists. Fair value estimates are based on assumptions believed to be reasonable at the time, but such assumptions are subject to inherent uncertainty. Actual results may differ materially from those estimates. Any changes in key assumptions or management judgment with respect to a reporting unit or its prospects, which may result from a decline in Griffon’s stock price, a change in market conditions, market trends, interest rates or other factors outside of Griffon’s control, or significant underperformance relative to historical or projected future operating results, could result in a significantly different estimate of the fair value of Griffon’s reporting units, which could result in an impairment charge in the future. Leases On October 1, 2019, the Company adopted the Accounting Standards Codifications ("ASC") Topic 842, Leases, which requires the recording of operating lease Right-of-Use ("ROU") assets and operating lease liabilities. Finance leases were not impacted by the adoption of ASC Topic 842, as finance lease liabilities and the corresponding assets were already recorded in the balance sheet under the previous guidance, ASC Topic 840. The Company has elected the package of practical expedients permitted under the transition guidance within the new standard, which among other things, allows us to carry forward the historical lease classification. We also elected a practical expedient to determine the reasonably certain lease term. The Company applied the modified retrospective ap

REVENUE

REVENUE	12 Months Ended
	Sep. 30, 2020
Revenue from Contract with Customer [Abstract]
REVENUE	REVENUE The Company recognizes revenue when performance obligations identified under the terms of contracts with its customers are satisfied. A performance obligation is a promise in a contract to transfer a distinct good or service, or a bundle of goods or services, to the customer, and is the unit of accounting. A contract with a customer is an agreement which both parties have approved, that creates enforceable rights and obligations, has commercial substance and with respect to which payment terms are identified and collectability is probable. Once the Company has entered into a contract or purchase order, it is evaluated to identify performance obligations. For each performance obligation, revenue is recognized when control of the promised products is transferred to the customer, or services are satisfied under the contract or purchase order, in an amount that reflects the consideration the Company expects to be entitled to in exchange for those products or services (the transaction price). A contract's transaction price is allocated to each distinct performance obligation and recognized as revenue when each performance obligation is satisfied. A majority of the Company’s contracts have a single performance obligation which represents, in most cases, the product being sold to the customer. To a lesser extent, some contracts include multiple performance obligations such as a product, the related installation, and extended warranty services. These contracts require judgment in determining the number of performance obligations. For contracts with multiple performance obligations, judgment is required to determine whether performance obligations specified in these contacts are distinct and should be accounted for as separate revenue transactions for recognition purposes. In these types of contracts, the Company allocates the total transaction price to each performance obligation in an amount based on the estimated relative standalone selling prices of the promised goods or services underlying each performance obligation. The Company uses an observable price to determine the stand-alone selling price for separate performance obligations or a cost plus margin approach when one is not available. The transaction price includes variable consideration, such as discounts and volume rebates, when it is probable that a significant reversal of revenue recognized will not occur. Variable consideration is determined using either the expected value or the most likely amount of consideration to be received based on historical experience and the specific facts and circumstances at the time of evaluation. See Note 19 - Business Segments for revenue from contracts with customers disaggregated by end markets, segments and geographic location. Revenue from CPP and HBP Segments Approximately 86% of the Company’s performance obligations are recognized at a point in time related to the manufacture and sale of a broad range of products and components primarily within the CPP and HBP Segments, and revenue is recognized when title, and risk and rewards of ownership, have transferred to the customer, which is generally upon shipment. A majority of CPP's and HBP's revenue is short cycle in nature with shipments occurring within one year from order and does not include a material long-term financing component, implicitly or explicitly. Payment terms generally range between 15 to 90 days and vary by the location of the business, the type of products manufactured to be sold and the volume of products sold, among other factors. The Company’s CPP and HBP Segments recognize revenue from product sales when all factors are met, including when control of a product transfers to the customer upon its shipment, completion of installation, testing, certification or other substantive acceptance required under the contract. Other than standard product warranty provisions, sales arrangements provide for no other significant post-shipment obligations on the Company. From time-to-time and for certain customers, rebates and other sales incentives, promotional allowances or discounts are offered, typically related to customer purchase volumes, all of which are fixed or determinable and are classified as a reduction of revenue and recorded at the time of sale. Griffon provides for sales returns and allowances based upon historical returns experience. The Company includes shipping costs billed to customers in revenue and the related shipping costs in Cost of Goods and Services. The majority of the Company’s contracts in the CPP and HBP Segments offer assurance-type warranties in connection with the sale of a product to a customer. Assurance-type warranties provide a customer with assurance that the related product will function as the parties intended because it complies with agreed-upon specifications. Such warranties do not represent a separate performance obligation. Payment terms in the CPP and HBP Segments vary depending on the type and location of the customer and the products or services offered. Generally, the period between the time revenue is recognized and the time payment is due is not significant. Shipping and handling charges are not considered a separate performance obligation. Additionally, all taxes assessed by a governmental authority that are both imposed on and concurrent with a specific revenue-producing transaction and collected from a customer (e.g., sales, use, value added, and some excise taxes) are excluded from revenue. Revenue from Defense Electronics Segment Approximately 14% of the Company’s performance obligations are recognized over time and relate to prime or subcontractors from contract awards with the U.S. Government, as well as foreign governments and other commercial customers within our DE Segment. Revenue recognized over time is generally accounted for using an input measure to determine progress completed at the end of the period. We believe that cumulative costs incurred to date as a percentage of estimated total contract costs at completion (cost-to-cost method) is an appropriate measure of progress towards satisfaction of performance obligations recognized over time, as it most accurately depicts the progress of our work and transfer of control to our customers. The Company’s DE Segment earns a substantial portion of its revenue as either a prime contractor or subcontractor from contract awards with the U.S. Government, as well as foreign governments and other commercial customers to design, develop and manufacture highly sophisticated intelligence, surveillance and communications solutions. These contracts are typically long-term in nature, usually greater than one year, and do not include a material long-term financing component, either implicitly or explicitly. Revenue and profits from such contracts are recognized over time as work is performed because control of the work in process transfers continuously to the customer. For U.S. Government contracts, the continuous transfer of control to the customer is supported by contract clauses that provide for: (i) progress or performance-based payments or (ii) the unilateral right of the customer to terminate the contract for convenience, in which case we have the right to receive payment for costs incurred plus a reasonable profit for products and services that do not have alternative use to us. Foreign government and certain commercial contracts contain similar termination for convenience clauses, or we have a legally enforceable right to receive payment for costs incurred and a reasonable profit for product or services that do not have alternative use to us. Revenue and profits on fixed-price and cost-plus contracts that include performance obligations satisfied over time are recorded at amounts equal to the ratio of actual cumulative costs incurred divided by total estimated costs at completion, multiplied by the total estimated contract revenue, less the cumulative revenue recognized in prior periods. The profit recorded on a contract using this method is equal to the current estimated total profit margin multiplied by the cumulative revenue recognized, less the amount of cumulative profit previously recorded for the contract in prior periods. Accounting for the sales and profits on performance obligations for which progress is measured using the cost-to-cost method relies on the substantial use of estimates, these projections may be revised throughout the life of a contract. Components of this formula and ratio that may be estimated include gross profit margin and total costs at completion. The cost performance and estimates to complete long-term contracts are reviewed, at a minimum, on a quarterly basis, as well as when information becomes available that would necessitate a review of the current estimate. Adjustments to estimates for a contract's estimated costs at completion and estimated profit or loss are often required as experience is gained, more information is obtained (even though the scope of work required under the contract may or may not change) and contract modifications occur. The impact of such adjustments to estimates is made on a cumulative basis in the period when such information has become known. The 2020, 2019, and 2018 income from operations included net favorable/(unfavorable) catch-up adjustments approximating $(10,650) , $(4,500) and $1,400 , respectively. Gross profit is impacted by a variety of factors, including the mix of products, systems and services, production efficiencies, price competition and general economic conditions. Under fixed-price contracts, the Company agrees to perform the specified work for a pre-determined price. To the extent actual costs vary from the estimates upon which the price was negotiated, more or less profit will be generated, or a loss could be incurred. Cost-reimbursable type contracts provide for the payment of allowable costs incurred on the contract plus the estimated profit on those costs. The estimated profit on a cost-reimbursable contract may be fixed or variable based on the contractual fee arrangement. We provide our products and services under cost-plus-fixed-fee arrangements. The fixed fee is negotiated at the inception of the contract and that fixed-fee does not vary with actual costs. For contracts in which anticipated total costs exceed the total expected revenue, an estimated loss is recognized in the period when identifiable. A provision for the entire amount of the estimated loss is recorded on a cumulative basis. The estimated remaining costs to complete loss contracts as of September 30, 2020 was $10,800 and is recorded as a reduction to gross margin on the Consolidated Statements of Operations and Comprehensive Income (Loss). This loss had an immaterial impact on Griffon's Consolidated Financial Statements. Contract modifications routinely occur to account for changes in contract specifications or requirements. Depending on the nature of the modification, we consider whether to account for the modification as an adjustment to the existing contract or as a separate contract. Contract modifications for goods or services that are not distinct are accounted for as part of the existing contract on a cumulative catch-up basis. From time to time, Telephonics may combine contracts if they are negotiated together, have specific requirements to combine, or are otherwise closely related. Transaction Price Allocated to the Remaining Performance Obligations On September 30, 2020, we had $380,000 of remaining performance obligations, which we also refer to as total backlog. We expect to recognize approximately 67% of our remaining performance obligations as revenue within one year, with the balance to be completed thereafter. Backlog represents the dollar value of funded orders for which work has not been performed. Backlog generally increases with bookings, and converts into revenue as we incur costs related to contractual commitments or the shipment of product. Given the nature of our business and a larger dependency on international customers, our bookings, and therefore our backlog, is impacted by the longer maturation cycles resulting in delays in the timing and amounts of such awards, which are subject to numerous factors, including fiscal constraints placed on customer budgets; political uncertainty; the timing of customer negotiations; and the timing of governmental approvals. Contract Balances Contract assets were $84,426 as of September 30, 2020 compared to $105,111 as of September 30, 2019. The $20,685 decrease in our contract assets balance was primarily due to the timing of billings and work performed on various radar and surveillance programs. Contract assets primarily relate to the Company's right to consideration for work completed but not billed at the reporting date and are recorded in Contract assets, net of progress payments in the Consolidated Balance Sheets. Contract assets are transferred to receivables when the right to consideration becomes unconditional. Contract costs and recognized income not yet billed consists of amounts accounted for under the percentage of completion method of accounting, recoverable costs and accrued profit that cannot yet be invoiced under the terms of certain long-term contracts. Amounts will be invoiced when applicable contract terms, such as the achievement of specified milestones or product delivery, are met. At September 30, 2020 and 2019, approximately $7,500 and $13,100 , respectively, of contract assets were expected to be collected after one year. Contract liabilities were $24,386 as of September 30, 2020 compared to $26,259 as of September 30, 2019. The $1,873

ACQUISITIONS

ACQUISITIONS	12 Months Ended
	Sep. 30, 2020
Business Combinations [Abstract]
ACQUISITIONS	ACQUISITIONS Griffon accounts for acquisitions under the acquisition method, in which assets acquired and liabilities assumed are recorded at fair value as of the date of acquisition using a method substantially similar to the goodwill impairment test methodology (level 3 inputs). The operating results of the acquired companies are included in Griffon’s consolidated financial statements from the date of acquisition in each instance. On November 29, 2019, AMES acquired 100% of the outstanding stock of Vatre Group Limited ("Apta"), a leading United Kingdom supplier of innovative garden pottery and associated products sold to leading UK and Ireland garden centers for approximately $10,500 (GBP 8,750 ), inclusive of a post-closing working capital adjustment, net of cash acquired. This acquisition broadens AMES' product offerings in the UK market and increases its in-country operational footprint. The excess of the purchase price over the fair value of the net tangible and intangible assets was recorded as goodwill and is deductible for tax purposes. The purchase price was primarily allocated to goodwill of GBP 3,449 , acquired intangible assets of GBP 3,454 , inventory of GBP 2,914 , accounts receivable and other assets of GBP 2,492 and accounts payable and other accrued liabilities of GBP 3,765 . On June 4, 2018, Clopay completed the acquisition of 100% of the outstanding stock of CornellCookson, a leading US manufacturer and marketer of rolling steel door and grille products designed for commercial, industrial, institutional and retail use, for approximately $180,000 , excluding the estimated present value of tax benefits, and $12,426 of post-closing adjustments, primarily consisting of a working capital adjustment. CornellCookson revenue in 2018 was $66,654 . The acquisition of CornellCookson substantially expanded Clopay’s non-residential product offerings, and added an established professional dealer network focused on rolling steel door and grille products for commercial, industrial, institutional and retail use. CornellCookson’s accounts, affected for adjustments to reflect fair market values assigned to assets purchased and liabilities assumed, and results of operations are included in the Company’s consolidated financial statements from the date of acquisition. The Company has recorded an allocation of the purchase price to the Company’s tangible and identifiable intangible assets acquired and liabilities assumed based on their fair market values (level 3 inputs) at the acquisition date. The excess of the purchase price over the fair value of the net tangible and intangible assets was recorded as goodwill and is deductible for tax purposes. Goodwill recognized at the acquisition date represents the other intangible benefits that the Company will derive from the ownership of CornellCookson, however, such intangible benefits do not meet the criteria for recognition of separately identifiable intangible assets. The calculation of the purchase price allocation is as follows: Accounts receivable (1) $ 30,400 Inventories (2) 12,336 Property, plant and equipment 49,426 Goodwill 43,183 Intangible assets 67,600 Other current and non-current assets 2,648 Total assets acquired 205,593 Accounts payable and accrued liabilities 12,507 Long-term liabilities 660 Total liabilities assumed 13,167 Total $ 192,426 (1) Includes $30,818 of gross accounts receivable of which $418 was not expected to be collected. The fair value of accounts receivable approximated book value acquired. (2) Includes $13,434 of gross inventory of which $1,098 was reserved for obsolete items. The amounts assigned to goodwill and major intangible asset classifications, all of which are tax deductible, for the CornellCookson acquisition are as follows: Average Goodwill $ 43,183 N/A Indefinite-lived intangibles 53,500 N/A Definite-lived intangibles 14,100 12 Total goodwill and intangible assets $ 110,783 On February 13, 2018, AMES acquired 100% of the outstanding stock of Kelkay Limited ("Kelkay"), a leading United Kingdom manufacturer and distributor of decorative outdoor landscaping products sold to garden centers, retailers and grocers in the UK and Ireland for $56,118 (GBP 40,452 ), subject to contingent consideration of up to GBP 7,000 , of which approximately GBP 2,200 was earned. This acquisition broadened AMES' product offerings in the market and increased its in-country operational footprint. The purchase price was primarily allocated to tradenames of GBP 19,000 , customer related intangibles of GBP 6,640 , accounts receivable and inventory of GBP 8,894 and fixed assets and land of GBP 8,241 . On November 6, 2017, AMES acquired substantially all of the assets of Harper Brush Works ("Harper"), a division of Horizon Global, for $4,383 , inclusive of post-closing adjustments. Harper is a leading U.S. manufacturer of cleaning products for professional, home, and industrial use. The acquisition expanded AMES’ long-handled tool offering in North America to include brooms, brushes, and other cleaning tools and accessories. The purchase price was primarily allocated to intangible assets of $2,300 , inventory and accounts receivable of $3,900 and fixed assets of $900 . On October 2, 2017, Griffon Corporation completed the acquisition of 100% of the outstanding equity interests of ClosetMaid, a market leader of home storage and organization products, for approximately $185,700 , inclusive of certain post-closing adjustments and excluding the present value of net tax benefits resulting from the transaction. The acquisition of ClosetMaid expanded Griffon’s Home and Building Products segment into the highly complementary home storage and organization category with a leading brand and product portfolio. ClosetMaid's accounts, affected for adjustments to reflect fair market values assigned to assets purchased and liabilities assumed, and results of operations, are included in the Company’s consolidated financial statements from the date of acquisition. The Company has recorded an allocation of the purchase price to the Company’s tangible and identifiable intangible assets acquired and liabilities assumed based on their fair market values (level 3 inputs) at the acquisition date. The excess of the purchase price over the fair value of the net tangible and intangible assets was recorded as goodwill and is deductible for tax purposes. Goodwill recognized at the acquisition date represents the other intangible benefits that the Company will derive from the ownership of ClosetMaid, however, such intangible benefits do not meet the criteria for recognition of separately identifiable intangible assets. The calculation of the purchase price allocation is as follows: Accounts receivable (1) $ 32,234 Inventories (2) 28,411 Property, plant and equipment 47,464 Goodwill 70,159 Intangible assets 74,580 Other current and non-current assets 3,852 Total assets acquired 256,700 Accounts payable and accrued liabilities 68,251 Long-term liabilities 2,720 Total liabilities assumed 70,971 Total $ 185,729 (1) Includes $32,956 of gross accounts receivable of which $722 was not expected to be collected. The fair value of accounts receivable approximated book value acquired. (2) Includes $1,500 in inventory basis step-up, which was charged to cost of goods sold over the inventory turns of the acquired entity. The amounts assigned to goodwill and major intangible asset classifications, all of which are tax deductible, for the ClosetMaid acquisition are as follows: Average Goodwill $ 70,159 N/A Indefinite-lived intangibles 47,740 N/A Definite-lived intangibles 26,840 21 Total goodwill and intangible assets $ 144,739 During the year ended September 30, 2020, SG&A included acquisition costs of $2,960 . There were no acquisition-related costs in 2019. In 2018, SG&A and Cost of goods and services included $6,097 and $1,500

INVENTORIES

INVENTORIES	12 Months Ended
	Sep. 30, 2020
Inventory Disclosure [Abstract]
INVENTORIES	INVENTORIES The following table details the components of inventory: At September 30, At September 30, Raw materials and supplies $ 135,083 $ 121,791 Work in process 81,624 93,830 Finished goods 197,118 226,500 Total $ 413,825 $ 442,121

PROPERTY, PLANT AND EQUIPMENT

PROPERTY, PLANT AND EQUIPMENT	12 Months Ended
	Sep. 30, 2020
Property, Plant and Equipment [Abstract]
PROPERTY, PLANT AND EQUIPMENT	PROPERTY, PLANT AND EQUIPMENT The following table details the components of property, plant and equipment, net: At September 30, At September 30, Land, building and building improvements $ 167,005 $ 133,036 Machinery and equipment 595,126 580,698 Leasehold improvements 53,386 49,808 815,517 763,542 Accumulated depreciation and amortization (471,553 ) (426,216 ) Total $ 343,964 $ 337,326

GOODWILL AND OTHER INTANGIBLES

GOODWILL AND OTHER INTANGIBLES	12 Months Ended
	Sep. 30, 2020
Goodwill and Intangible Assets Disclosure [Abstract]
GOODWILL AND OTHER INTANGIBLES	GOODWILL AND OTHER INTANGIBLES Griffon usually performs its annual goodwill impairment testing in the fourth quarter of each year. In addition to the annual impairment test, the Company is required to regularly assess whether a triggering event has occurred which would require interim impairment testing. Given the general deterioration in economic and market conditions surrounding the COVID-19 pandemic, the Company considered the impact that the COVID-19 pandemic may have on its near and long-term forecasts and completed an interim impairment test as of March 31, 2020. The Company determined that there was no impairment to either its goodwill or indefinite-lived intangible assets at March 31, 2020. As of September 30, 2020 , the Company performed a qualitative assessment and determined it was not more likely than not that the fair value of any of its reporting units or its indefinite-lived intangible assets was less than their carrying values. Based upon the results of the annual impairment qualitative review, it was determined that the fair value of each reporting unit substantially exceeded the carrying value of the assets, as performed under step one, and no impairment existed. See Note 1, Description of Business and Summary of Significant Accounting Policies, for a description of the Company's goodwill and indefinite-lived intangible impairment testing methodology. The following table provides changes in carrying value of goodwill by segment through the year ended September 30, 2020 : At September 30, Goodwill from acquisitions Reallocation of Goodwill (1) Foreign currency translation adjustments At September 30, Goodwill from acquisitions Foreign currency translation adjustments At September 30, Consumer and Professional Products $ 378,046 $ — $ (148,076 ) $ (2,701 ) $ 227,269 $ 4,451 $ 1,125 $ 232,845 Home and Building Products 42,804 300 148,076 73 191,253 — — 191,253 Defense Electronics 18,545 — — — 18,545 — — 18,545 Total $ 439,395 $ 300 $ — $ (2,628 ) $ 437,067 $ 4,451 $ 1,125 $ 442,643 (1) In accordance with the guidance set forth in ASC 350, and in connection with the modification of the Company's reportable segment structure, using a relative fair value approach, the Company reallocated $148,076 of goodwill between the CPP and HBP segments. The following table provides the gross carrying value and accumulated amortization for each major class of intangible asset: At September 30, 2020 At September 30, 2019 Gross Carrying Amount Accumulated Amortization Average Life (Years) Gross Carrying Amount Accumulated Amortization Customer relationships & other $ 185,940 $ 66,656 23 $ 183,515 $ 57,783 Unpatented technology 19,464 8,360 13 19,167 7,329 Total amortizable intangible assets 205,404 75,016 202,682 65,112 Trademarks 224,640 — 219,069 — Total intangible assets $ 430,044 $ 75,016 $ 421,751 $ 65,112 Amortization expense for intangible assets subject to amortization was $9,590 , $9,922 and $9,070 in 2020, 2019 and 2018, respectively. Amortization expense for each of the next five years and thereafter, based on current intangible balances and classifications, is estimated as follows: 2021 - $9,443 ; 2022 - $9,436 ; 2023 - $9,357 ; 2024 - $9,331 and 2025 - $9,331 ; thereafter - $83,490 .

DISCONTINUED OPERATIONS

DISCONTINUED OPERATIONS	12 Months Ended
	Sep. 30, 2020
Discontinued Operations and Disposal Groups [Abstract]
DISCONTINUED OPERATIONS	DISCONTINUED OPERATIONS During 2019, Griffon recorded an $11,050 charge ( $8,335 , net of tax) to discontinued operations. The charge consisted primarily of a purchase price adjustment to resolve a claim related to the $465,000 Plastics divestiture and included an additional reserve for a legacy environmental matter. The following amounts summarize the total assets and liabilities of Plastics and Installation Services and other discontinued activities which have been segregated from Griffon’s continuing operations and are reported as assets and liabilities of discontinued operations in the consolidated balance sheets: At September 30, At September 30, Assets of discontinued operations: Prepaid and other current assets $ 2,091 $ 321 Other long-term assets 6,406 2,888 Total assets of discontinued operations $ 8,497 $ 3,209 Liabilities of discontinued operations: Accrued liabilities, current $ 3,797 $ 4,333 Other long-term liabilities 7,014 3,331 Total liabilities of discontinued operations $ 10,811 $ 7,664 At September 30, 2020 , Griffon’s liabilities for Plastics, Installations Services and other discontinued operations primarily related to insurance claims, income taxes and product liability, warranty and environmental reserves totaling liabilities of approximately $10,811 . The increase in assets and liabilities were primarily associated with insurance claims receivable and payable. Plastics On November 16, 2017, Griffon announced it entered into a definitive agreement to sell Plastics and on February 6, 2018, completed the sale to Berry for approximately $465,000 , net of certain post-closing adjustments. As a result, Griffon classified the results of operations of the Plastics business as discontinued operations in the Consolidated Statements of Operations for all periods presented and classified the related assets and liabilities associated with the discontinued operations in the consolidated balance sheets. Plastics is a global leader in the development and production of embossed, laminated and printed specialty plastic films for hygienic, health-care and industrial products and sells to some of the world's largest consumer products companies. In connection with the sale of Plastics, the Company recorded a $9,500 post-closing adjustment ( $7,085 , net of tax) during 2019 and recorded a gain on sale of $112,964 ( $81,041 , net of tax) during 2018. The following amounts related to the Plastics segment have been segregated from Griffon's continuing operations and are reported as discontinued operations: For the Year Ended September 30, 2019 2018 Revenue $ — $ 166,262 Cost of goods and services — 132,100 Gross profit — 34,162 Selling, general and administrative expenses 9,500 26,303 Restructuring charges — — Total operating expenses 9,500 26,303 Income from discontinued operations (9,500 ) 7,859 Other income (expense) Gain on sale of business — 112,964 Interest expense, net — (155 ) Other, net — (687 ) Total other income (expense) — 112,122 Income from operations of discontinued operations (9,500 ) 119,981 Installation Services and Other Discontinued Activities There was no reported revenue in 2020, 2019 and 2018.

ACCRUED LIABILITIES

ACCRUED LIABILITIES	12 Months Ended
	Sep. 30, 2020
Payables and Accruals [Abstract]
ACCRUED LIABILITIES	ACCRUED LIABILITIES The following table details the components of accrued liabilities: At September 30, At September 30, Compensation $ 83,308 $ 61,639 Interest 4,371 4,501 Warranties and rebates 18,687 13,171 Insurance 10,997 11,996 Rent, utilities and freight 8,816 5,326 Income and other taxes 14,707 7,814 Marketing and advertising 7,968 4,417 Restructuring 2,965 — Other 19,753 15,801 Total $ 171,572 $ 124,665

RESTRUCTURING CHARGES

RESTRUCTURING CHARGES	12 Months Ended
	Sep. 30, 2020
Restructuring and Related Activities [Abstract]
RESTRUCTURING CHARGES	RESTRUCTURING CHARGES In September 2020, Telephonics initiated a Voluntary Employee Retirement Plan, which was subsequently followed by a reduction in force in November 2020, to improve efficiencies by combining functions and responsibilities. The combined actions are expected to incur severance charges of approximately $4,500 , with $2,120 recognized in the fourth quarter, and the balance to be recognized in the first quarter of 2021. At the conclusion of these actions, headcount is expected to be reduced by approximately 90 people. In addition, during fiscal 2020 Telephonics commenced a facility project to consolidate three Long Island based facilities into two company owned facilities with a total cost of approximately $4.0 million primarily comprised of capital expenditures in 2021. In November 2019, Griffon announced the development of a next-generation business platform for CPP to enhance the growth, efficiency, and competitiveness of its U.S. operations, and on November 12, 2020, Griffon announced that CPP is broadening this strategic initiative to include additional North American facilities, the AMES UK and Australia businesses, and a manufacturing facility in China. The expanded focus of this initiative leverages the same three key development areas being executed within our U.S. operations. First, multiple independent information systems will be unified into a single data and analytics platform, which will serve the whole AMES global enterprise. Second, certain AMES global operations will be consolidated to optimize facilities footprint and talent. Third, strategic investments in automation and facilities expansion will be made to increase the efficiency of our manufacturing and fulfillment operations, and support e-commerce growth. The cost to implement this new business platform, over the five years duration of the project, will include approximately $65,000 (increased from $35,000 ) of one-time charges and approximately $65,000 (increased from $40,000 ) in capital investments. The one-time charges are comprised of $46,000 of cash charges, which includes $26,000 of personnel-related costs such as training, severance, and duplicate personnel costs as well as $20,000 of facility and lease exit costs. The remaining $19,000 of charges are non-cash and are primarily related to asset write-downs. In the year ended September 30, 2020, CPP incurred pre-tax restructuring and related exit costs approximating $13,669 . For the year ended September 30, 2020, cash charges totaled $8,977 and non-cash, asset-related charges totaled $4,692 ; the cash charges included $5,620 for one-time termination benefits and other personnel-related costs and $3,357 for facility exit costs. Non-cash charges included a $1,968 impairment charge related to a facility’s operating lease as well as $671 of leasehold improvements made to the leased facility and $304 of inventory that have no recoverable value, and a $1,749 impairment charge related to machinery and equipment that have no recoverable value at one of the Company's owned manufacturing locations. As a result of these transactions, headcount was reduced by 167 . A summary of the restructuring and other related charges included in Cost of goods and services and Selling, general and administrative expenses in the Company's Consolidated Statements of Operations were as follows: For the Year Ended September 30, 2020 Cost of goods and services $ 4,159 Selling, general and administrative expenses 11,630 Total restructuring charges $ 15,789 For the Year Ended September 30, 2020 Personnel related costs $ 7,740 Facilities, exit costs and other 3,357 Non-cash facility and other 4,692 Total $ 15,789 The following table summarizes the accrued liabilities of the Company's restructuring actions: Cash Charges Cash Charges Non Cash Charges Personnel related costs Facilities & Facility and Other Costs Total Accrued liability at September 30, 2019 $ — $ — $ — $ — Charges 7,740 3,357 4,692 15,789 Payments (5,039 ) (3,093 ) — (8,132 ) Non-cash charges (1) — $ — (4,692 ) (4,692 ) Accrued liability at September 30, 2020 $ 2,701 $ 264 $ — $ 2,965 (1) Non-cash charges in Facility and Other Costs primarily represent the non-cash write-off of certain long-lived assets in connection with certain facility closures.

WARRANTY LIABILITY

WARRANTY LIABILITY	12 Months Ended
	Sep. 30, 2020
Product Warranties Disclosures [Abstract]
WARRANTY LIABILITY	WARRANTY LIABILITY DE offers warranties against product defects for periods generally ranging from one to two years , depending on the specific product and terms of the customer purchase agreement. CPP and HBP also offers warranties against product defects for periods generally ranging from one to ten years, with limited lifetime warranties on certain door models. Typical warranties require CPP, HBP and DE to repair or replace the defective products during the warranty period at no cost to the customer. At the time revenue is recognized, Griffon records a liability for warranty costs, estimated based on historical experience, and periodically assesses its warranty obligations and adjusts the liability as necessary. CPP offers an express limited warranty for a period of ninety days on all products from the date of the original purchase unless otherwise stated on the product or packaging from the date of original purchase. Changes in Griffon’s warranty liability, included in Accrued liabilities, were as follows: Years Ended September 30, 2020 2019 Balance, beginning of period $ 7,894 $ 8,174 Warranties issued and changes in estimated pre-existing warranties 20,474 16,938 Actual warranty costs incurred (17,525 ) (17,218 ) Balance, end of period $ 10,843 $ 7,894

LONG-TERM DEBT

LONG-TERM DEBT	12 Months Ended
	Sep. 30, 2020
Debt Disclosure [Abstract]
LONG-TERM DEBT	LONG-TERM DEBT Debt at September 30, 2020 and 2019 consisted of the following: At September 30, 2020 Outstanding Balance Original Issuer Premium Capitalized Fees & Expenses Balance Sheet Coupon Interest Rate Senior notes due 2028 (a) $ 1,000,000 $ 363 $ (15,376 ) $ 984,987 5.75 % Revolver due 2025 (b) 12,858 — (2,209 ) 10,649 Variable Finance lease - real estate (e) 17,218 — (30 ) 17,188 Variable Non U.S. lines of credit (f) — — (30 ) (30 ) Variable Non U.S. term loans (f) 31,086 — (160 ) 30,926 Variable Other long term debt (g) 3,260 — (16 ) 3,244 Variable Totals 1,064,422 363 (17,821 ) 1,046,964 less: Current portion (9,922 ) — — (9,922 ) Long-term debt $ 1,054,500 $ 363 $ (17,821 ) $ 1,037,042 At September 30, 2019 Outstanding Balance Original Issuer Premium Capitalized Balance Sheet Coupon Interest Rate Senior notes due 2022 (a) $ 1,000,000 $ 867 $ (9,175 ) $ 991,692 5.25 % Revolver due 2021 (b) 50,000 — (1,243 ) 48,757 Variable Finance lease - real estate (e) 4,388 — (55 ) 4,333 5.00 % Non U.S. lines of credit (f) 17,576 — (45 ) 17,531 Variable Non U.S. term loans (f) 36,977 — (188 ) 36,789 Variable Other long term debt (g) 5,190 — (18 ) 5,172 Variable Totals 1,114,131 867 (10,724 ) 1,104,274 less: Current portion (10,525 ) — — (10,525 ) Long-term debt $ 1,103,606 $ 867 $ (10,724 ) $ 1,093,749 Interest expense consists of the following for 2020, 2019 and 2018. Year Ended September 30, 2020 Effective Interest Rate Cash Interest Amort. Debt Premium Amort. Deferred Cost & Other Fees Total Interest Expense Senior notes due 2028 (a) 5.90 % $ 32,511 $ — $ 1,072 $ 33,583 Senior notes due 2022 (a) 5.67 % $ 22,816 $ 122 $ 1,735 $ 24,673 Revolver due 2025 (b) Variable 5,866 — 635 6,501 Finance lease - real estate (e) Variable 386 — 25 411 Non U.S. lines of credit (f) Variable 12 — 15 27 Non U.S. term loans (f) Variable 975 — 55 1,030 Other long term debt (g) Variable 445 — 2 447 Capitalized interest (128 ) — — (128 ) Totals $ 62,883 $ 122 $ 3,539 $ 66,544 Year Ended September 30, 2019 Effective Interest Rate Cash Interest Amort. Debt Premium Amort. Deferred Cost & Other Fees Total Interest Expense Senior notes due 2022 (a) 5.66 % $ 52,500 $ 270 $ 3,803 $ 56,573 Revolver due 2025 (b) Variable 6,998 — 980 7,978 ESOP Loans (d) 6.3 % 937 — 186 1,123 Finance lease - real estate (e) Variable 372 — 25 397 Non U.S. lines of credit (f) Variable 19 — 15 34 Non U.S. term loan (f) Variable 1,592 — 109 1,701 Other long term debt (g) Variable 640 — 5 645 Capitalized interest (385 ) — — (385 ) Totals $ 62,673 $ 270 $ 5,123 $ 68,066 Year Ended September 30, 2018 Effective Interest Rate Cash Interest Amort. Debt Amort. Deferred Cost & Other Fees Total Interest Expense Senior notes due 2022 (a) 5.66 % $ 52,500 $ 270 $ 3,803 $ 56,573 Revolver due 2025 (b) Variable 3,718 — 565 4,283 Real estate mortgages (c) 6.3 % 1,802 — 124 1,926 ESOP Loans (d) 3.3 % 349 — 320 669 Finance lease - real estate (e) Variable 581 — 25 606 Non U.S. lines of credit (f) Variable 34 — 15 49 Non U.S. term loan (f) Variable 1,420 — 90 1,510 Other long term debt (g) Variable 494 — 7 501 Capitalized interest (549 ) — — (549 ) Totals $ 60,349 $ 270 $ 4,949 $ 65,568 Minimum payments under debt agreements for the next five years are as follows: $9,922 in 2021 , $12,667 in 2022 , $16,124 in 2023 , $1,730 in 2024 , $14,628 in 2025 and $1,009,351 thereafter. (a) On June 22, 2020, in an unregistered offering through a private placement, Griffon completed the add-on offering of $150,000 principal amount of its 5.75% senior notes due 2028, at 100.25% of par, to Griffon's previously issued $850,000 principal amount of its 5.75% senior notes due 2028, at of par, completed on February 19, 2020 (collectively, the "Senior Notes"). Proceeds from the Senior Notes were used to redeem the $1,000,000 of 5.25% senior notes due 2022 (the "2022 Senior Notes"). As of September 30, 2020, outstanding Senior Notes due totaled $1,000,000 ; interest is payable semi-annually on March 1 and September 1. The Senior Notes are senior unsecured obligations of Griffon guaranteed by certain domestic subsidiaries, and subject to certain covenants, limitations and restrictions. On April 22, 2020 and August 3, 2020, Griffon exchanged substantially all of the Senior Notes for substantially identical Senior Notes registered under the Securities Act of 1933, as amended (the "Securities Act"), via an exchange offer. The fair value of the 2028 Senior Notes approximated $1,040,000 on September 30, 2020 based upon quoted market prices (level 1 inputs). In connection with these transactions, Griffon capitalized $16,448 of underwriting fees and other expenses incurred related to the issuance and exchange of the Senior Notes, which will amortize over the term of such notes, and, at September 30, 2020, $15,376 remained to be amortized. Furthermore, all of the obligations associated with the 2022 Senior Notes were discharged. Additionally, Griffon recognized a $7,925 loss on the early extinguishment of debt of the 5.25% $1,000,000 2022 Senior Notes, comprised primarily of the write-off of $6,725 of remaining deferred financing fees, $607 of tender offer net premium expense and $593 of redemption interest expense. (b) On January 30, 2020, Griffon amended its Credit Agreement to increase the maximum borrowing availability from $350,000 to $400,000 , extend its maturity from March 22, 2021 to March 22, 2025 and modify certain other provisions of the facility. The facility includes a letter of credit sub-facility with a limit of $100,000 (increased from $50,000 ); and a multi-currency sub-facility of $100,000 . The Credit Agreement provides for same day borrowings of base rate loans. Borrowings under the Credit Agreement may be repaid and re-borrowed at any time. Interest is payable on borrowings at either a LIBOR or base rate benchmark rate, plus an applicable margin, which adjusts based on financial performance. Current margins are 0.75% for base rate loans and 1.75% for LIBOR loans. The Credit Agreement has certain financial maintenance tests including a maximum total leverage ratio, a maximum senior secured leverage ratio and a minimum interest coverage ratio, as well as customary affirmative and negative covenants and events of default. The negative covenants place limits on Griffon's ability to, among other things, incur indebtedness, incur liens, and make restricted payments and investments. Borrowings under the Credit Agreement are guaranteed by Griffon’s material domestic subsidiaries and are secured, on a first priority basis, by substantially all domestic assets of the Company and the guarantors, and a pledge of not greater than 65% of the equity interest in Griffon’s material, first-tier foreign subsidiaries. At September 30, 2020 , under the Credit Agreement, there were $12,858 in outstanding borrowings; outstanding standby letters of credit were $16,867 ; and $370,275 was available, subject to certain loan covenants, for borrowing at that date. (c) In September 2015 and March 2016, Griffon entered into mortgage loans in the amount of $32,280 and $8,000 , respectively, that were due to mature in September 2025 and April 2018, respectively. The mortgage loans were secured and collateralized by four properties occupied by Griffon's subsidiaries and were guaranteed by Griffon. The loans had an interest at a rate of LIBOR plus 1.50% . The loans were paid off during 2018. (d) In August 2016 and as amended on June 30, 2017, Griffon’s ESOP entered into a Term Loan with a bank (the "ESOP Agreement"). The Term Loan interest rate was LIBOR plus 3.00% . The Term Loan required quarterly principal payments of $569 with a balloon payment due at maturity. The Term Loan was secured by shares purchased with the proceeds of the loan and with a lien on a specific amount of Griffon assets (which ranked pari passu with the lien granted on such assets under the Credit Agreement) and was guaranteed by Griffon. On March 13, 2019, the ESOP Term Loan was refinanced with an internal loan from Griffon which was funded with cash and a draw under its Credit Agreement. The internal loan interest rate is fixed at 2.91% , matures in June 2033 and requires quarterly payments of principal, currently $635 , and interest. The internal loan is secured by shares purchased with the proceeds of the loan. The amount outstanding on the internal loan at September 30, 2020 was $29,878 . (e) Two Griffon subsidiaries have finance leases outstanding for real estate located in Troy, Ohio and Ocala, Florida. The leases mature in 2021 and 2025, respectively, and bear interest at fixed rates of approximately 5.0% and 5.6% , respectively. The Troy, Ohio lease is secured by a mortgage on the real estate and is guaranteed by Griffon. The Ocala, Florida lease contains two five-year renewal options. As of September 30, 2020, $17,188 was outstanding, net of issuance costs. Refer to Note 22 - Leases for further details. (f) In November 2012, Garant G.P. (“Garant”), a Griffon subsidiary, entered into a CAD 15,000 ( $11,210 as of September 30, 2020) revolving credit facility. The facility accrues interest at LIBOR (USD) or the Bankers Acceptance Rate (CDN) plus 1.3% per annum ( 1.44% LIBOR USD and 1.55% Bankers Acceptance Rate CDN as of September 30, 2020 ). The revolving facility matures in October 2022. Garant is required to maintain a certain minimum equity. As of September 30, 2020 , there were no borrowings under the revolving credit facility with CAD 15,000 ( $11,210 as of September 30, 2020 ) available for borrowing. In July 2016, Griffon Australia Holdings Pty Ltd and its Australian subsidiaries ("Griffon Australia") entered into an AUD 29,625 term loan, AUD 20,000 revolver and AUD 10,000 receivable purchase facility agreement; the agreement was amended in March 2019. As amended, the term loan requires quarterly principal payments of AUD 1,250 plus interest with a balloon payment of AUD 9,625 due upon maturity in March 2022, and accrues interest at Bank Bill Swap Bid Rate “BBSY” plus 1.95% per annum ( 2.09% at September 30, 2020 ). During the year ended September 30, 2020, the term loan balance was reduced by AUD 5,000 from AUD 23,375 to AUD 18,375 with proceeds from an AUD 5,000 increase in the commitment of the receivables purchase line from AUD 10,000 to AUD 15,000 . As of September 30, 2020 , the term loan had an outstanding balance of AUD 15,875 ( $11,287 as of September 30, 2020). The revolving facility and receivable purchase facility mature in March 2022, but are renewable upon mutual agreement with the lender. The revolving facility and receivable purchase facility accrue interest at BBSY plus 1.9% and 1.35% , respectively, per annum ( 2.04% and 1.49% , respectively, at September 30, 2020). At September 30, 2020, there were no balances outstanding under the revolver and the receivable purchase facility. The revolver, receivable purchase facility and term loan are all secured by substantially all of the assets of Griffon Australia and its subsidiaries. Griffon Australia is required to maintain a certain minimum equity level and is subject to a maximum leverage ratio and a minimum fixed charges cover ratio. In July 2018, the AMES Companies UK Ltd and its subsidiaries (collectively, "Ames UK") entered into a GBP 14,000 term loan, GBP 4,000 mortgage loan and GBP 5,000 revolver. The term loan and mortgage loan require quarterly principal payments of GBP 438 and GBP 105 plus interest, respectively, and have balloon payments due upon maturity, July 2023, of GBP 7,088 and GBP 2,349 , respectively. The term loan and mortgage loan accrue interest at the GBP LIBOR Rate plus 2.25% and 1.8% , respectively ( 2.30% and 1.85% at September 30, 2020, respectively). The revolving facility matures in May 2021, but is renewable upon mutual agreement with the lender, and accrues interest at the Bank of England Base Rate plus 1.5% ( 1.85% as of September 30, 2020). As of September 30, 2020, the revolver had no outstanding balance while the term and mortgage loan balances amounted to GBP 15,398 ( $19,799 as of September 30, 2020). The revolver and the term loan are both secured by substantially all of the assets of AMES UK and its subsidiaries. AMES UK is subject to a maximum leverage ratio and a minimum fixed charges cover ratio. An invoice discounting arrangement was canceled and replaced by the above loan facilities. (g) Other long-term debt primarily consists of a loan with the Pennsylvania Industrial Development Authority, with the balance consisting of capital leases. At September 30, 2020 , Griffon and its subsidiaries were in compliance with the terms and covenants of its credit and loan agreements.

EMPLOYEE BENEFIT PLANS

EMPLOYEE BENEFIT PLANS	12 Months Ended
	Sep. 30, 2020
Retirement Benefits [Abstract]
EMPLOYEE BENEFIT PLANS	EMPLOYEE BENEFIT PLANS Griffon offers defined contribution plans to most of its U.S. employees. In addition to employee contributions to the plans, Griffon makes contributions based upon various percentages of compensation and/or employee contributions, which were $11,956 in 2020 , $11,788 in 2019 and $11,053 in 2018. The Company also provides healthcare and life insurance benefits for certain groups of retirees through several plans. For certain employees, the benefits are at fixed amounts per retiree and are partially contributory by the retiree. The post-retirement benefit obligation was $1,833 and $1,852 as of September 30, 2020 and 2019 . The accumulated other comprehensive income (loss) for these plans was $(196) and ($146) as of September 30, 2020 and 2019 , respectively, and the 2020 and 2019 benefit expense was $46 and $50 , respectively. It is the Company’s practice to fund these benefits as incurred. Griffon also has qualified and non-qualified defined benefit plans covering certain employees with benefits based on years of service and employee compensation. Over time, these amounts will be recognized as part of net periodic pension costs in the Consolidated Statements of Operations and Comprehensive Income (Loss). Griffon is responsible for overseeing the management of the investments of the qualified defined benefit plan and uses the services of an investment manager to manage these assets based on agreed upon risk profiles. The primary objective of the qualified defined benefit plan is to secure participant retirement benefits. As such, the key objective in this plan’s financial management is to promote stability and, to the extent appropriate, growth in the funded status. Financial objectives are established in conjunction with a review of current and projected plan financial requirements. The fair values of a majority of the plan assets were determined by the plans’ trustee using quoted market prices for identical instruments (level 1 inputs) as of September 30, 2020 and 2019. The fair value of various other investments was determined by the plan’s trustee using direct observable market corroborated inputs, including quoted market prices for similar assets (level 2 inputs). A small amount of plan assets are invested in private equity which consist primarily of investments in private companies which are valued using the net asset values provided by the underlying private investment companies as a practical expedient (level 3 inputs). The Clopay AMES Pension Plan and the AMES supplemental executive retirement plan are frozen to new entrants and participants in the plans no longer accrue benefits. The Company’s non-service cost components of net periodic benefit plan cost was a benefit of $1,559 , $3,148 and $3,649 during 2020, 2019, and 2018 respectively. Griffon uses judgment to establish the assumptions used in determining the future liability of the plan, as well as the investment returns on the plan assets. The expected return on assets assumption used for pension expense was developed through analysis of historical market returns, current market conditions and past experience of plan investments. The long-term rate of return assumption represents the expected average rate of earnings on the funds invested, or to be invested, to provide for the benefits included in the benefit obligations. The assumption is based on several factors including historical market index returns, the anticipated long-term asset allocation of plan assets and the historical return. The discount rate assumption is determined by developing a yield curve based on high quality bonds with maturities matching the plans’ expected benefit payment stream. The plans’ expected cash flows are then discounted by the resulting year-by-year spot rates. A 10% change in the discount rate or return on assets would not have a material effect on the financial statements of Griffon. Net periodic costs (benefits) were as follows: Defined Benefits for the Years Ended September 30, Supplemental Benefits for the Years Ended September 30, 2020 2019 2018 2020 2019 2018 Net periodic (benefits) costs: Interest cost $ 4,267 $ 5,778 $ 5,084 $ 335 $ 503 $ 544 Expected return on plan assets (10,343 ) (10,331 ) (10,736 ) — — — Amortization of: Prior service costs — — — 14 14 14 Actuarial loss 3,769 630 755 399 258 628 Total net periodic (benefits) costs $ (2,307 ) $ (3,923 ) $ (4,897 ) $ 748 $ 775 $ 1,186 The tax benefits in 2020 , 2019 and 2018 for the amortization of pension costs in Other comprehensive income (loss) were $878 , $221 and $342 , respectively. The estimated net actuarial loss and prior service cost that will be amortized from AOCI into Net periodic pension cost during 2021 is $6,277 and $15 , respectively. The weighted-average assumptions used in determining the net periodic (benefits) costs were as follows: Defined Benefits for the Years Ended September 30, Supplemental Benefits for the Years Ended September 30, 2020 2019 2018 2020 2019 2018 Discount rate 2.92 % 4.10 % 3.64 % 2.64 % 3.99 % 3.18 % Expected return on assets 7.00 % 7.00 % 7.25 % — % — % — % Plan assets and benefit obligation of the defined and supplemental benefit plans were as follows: Defined Benefits at September 30, Supplemental Benefits at September 30, 2020 2019 2020 2019 Change in benefit obligation: Benefit obligation at beginning of fiscal year $ 177,797 $ 161,328 $ 16,180 $ 15,718 Interest cost 4,267 5,778 335 503 Benefits paid (10,747 ) (10,790 ) (1,939 ) (1,942 ) Actuarial (gain) loss 11,686 21,481 1,494 1,901 Benefit obligation at end of fiscal year 183,003 177,797 16,070 16,180 Change in plan assets: Fair value of plan assets at beginning of fiscal year 145,610 150,680 — — Actual return on plan assets 4,261 2,606 — — Company contributions 8,021 3,114 1,939 1,942 Benefits paid (10,747 ) (10,790 ) (1,939 ) (1,942 ) Fair value of plan assets at end of fiscal year 147,145 145,610 — — Projected benefit obligation in excess of plan assets $ (35,858 ) $ (32,187 ) $ (16,070 ) $ (16,180 ) Amounts recognized in the statement of financial position consist of: Accrued liabilities $ — $ — $ (1,891 ) $ (1,906 ) Other liabilities (long-term) (35,858 ) (32,187 ) (14,179 ) (14,279 ) Total Liabilities (35,858 ) (32,187 ) (16,070 ) (16,185 ) Net actuarial losses 61,666 47,663 7,700 6,609 Prior service cost — — — 14 Deferred taxes (12,950 ) (17,098 ) (1,617 ) (2,374 ) Total Accumulated other comprehensive loss, net of tax 48,716 30,565 6,083 4,249 Net amount recognized at September 30, $ 12,858 $ (1,622 ) $ (9,987 ) $ (11,936 ) Accumulated benefit obligations $ 183,003 $ 177,797 $ 16,070 $ 16,180 Information for plans with accumulated benefit obligations in excess of plan assets: ABO $ 183,003 $ 177,797 $ 16,070 $ 16,180 PBO 183,003 177,797 16,070 16,180 Fair value of plan assets 147,145 145,610 — — The weighted-average assumptions used in determining the benefit obligations were as follows: Defined Benefits at September 30, Supplemental Benefits at September 30, 2020 2019 2020 2019 Weighted average discount rate 2.30 % 2.92 % 1.69 % 2.64 % Estimated future benefit payments to retirees, which reflect expected future service, are as follows: For the years ending September 30, Defined Benefits Supplemental Benefits 2021 $ 11,006 $ 1,891 2022 10,964 1,787 2023 10,945 1,679 2024 10,892 1,556 2025 10,809 1,437 2026 through 2030 52,390 5,354 During 2021, Griffon expects to contribute $1,891 in payments related to Supplemental Benefits that will be funded from the general assets of Griffon. Griffon expects to contribute $2,764 to the Defined Benefit plan in 2021 . The Clopay AMES Plan is covered by the Pension Protection Act of 2006. The Adjusted Funding Target Attainment Percent for the plan as of January 1, 2020 was 93.7% . Since the plan was in excess of the 80% funding threshold there were no plan restrictions. The expected level of 2021 catch up contributions is $2,107 . The actual and weighted-average asset allocation for qualified benefit plans were as follows: At September 30, 2020 2019 Target Cash and equivalents 0.4 % 1.9 % — % Equity securities 48.5 % 49.9 % 63.0 % Fixed income 31.9 % 29.4 % 37.0 % Other 19.2 % 18.8 % — % Total 100.0 % 100.0 % 100.0 % The following is a description of the valuation methodologies used for plan assets measured at fair value: Government and agency securities – When quoted market prices are available in an active market, the investments are classified as Level 1. When quoted market prices are not available in an active market, the investments are classified as Level 2. Equity securities – The fair values reflect the closing price reported on a major market where the individual mutual fund securities are traded in equity securities. These investments are classified within Level 1 of the valuation hierarchy. Debt securities – The fair values are based on a compilation of primarily observable market information or a broker quote in a non-active market where the individual mutual fund securities are invested in debt securities. These investments are classified within Level 1 and Level 2 of the valuation hierarchy. Commingled funds – The fair values are determined using NAV provided by the administrator of the fund. The NAV is based on the value of the underlying assets owned by the trust/entity, minus its liabilities, and then divided by the number of shares outstanding. These investments are generally classified within Level 2 or 3, as appropriate, of the valuation hierarchy and can be liquidated on demand. Interest in limited partnerships and hedge funds - One limited partnership investment is a private equity fund and the fair value is determined by the fund managers based on the net asset values provided by the underlying private investment companies as a practical expedient. These investments are classified within Level 2 of the valuation hierarchy. The following table presents the fair values of Griffon’s pension and post-retirement plan assets by asset category: At September 30, 2020 Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Total Cash and equivalents $ 600 $ — $ — $ 600 Government agency securities 33,675 6,136 — 39,811 Debt instruments 179 2,722 — 2,901 Equity securities 68,987 — — 68,987 Commingled funds — — 9,362 9,362 Limited partnerships and hedge fund investments — 17,867 — 17,867 Other Securities 2,488 163 — 2,651 Subtotal $ 105,929 $ 26,888 $ 9,362 $ 142,179 Accrued income and plan receivables 4,966 Total $ 147,145 At September 30, 2019 Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Total Cash and equivalents $ 2,791 $ — $ — $ 2,791 Government and agency securities 28,297 9,119 — 37,416 Debt instruments 182 2,996 — 3,178 Equity securities 72,517 — — 72,517 Commingled funds — — 8,776 8,776 Limited partnerships and hedge fund investments — 18,569 — 18,569 Other Securities 1,913 159 — 2,072 Subtotal $ 105,700 $ 30,843 $ 8,776 $ 145,319 Accrued income and plan receivables 291 Total $ 145,610 The following table represents level 3 significant unobservable inputs for the years ended September 30, 2020 and 2019: Significant As of October 1, 2019 $ — Purchases, issuances and settlements 7,695 Gains and losses 1,081 As of September 30, 2019 8,776 Purchases, issuances and settlements — Gains and losses 586 As of September 30, 2020 $ 9,362 Griffon has an ESOP that covers substantially all domestic employees. All U.S. employees of Griffon, who are not members of a collective bargaining unit, automatically become eligible to participate in the plan on the October 1 st following completion of one qualifying year of service (as defined in the plan). Securities are allocated to participants’ individual accounts based on the proportion of each participant’s aggregate compensation (not to exceed $285 for the plan year ended September 30, 2020 ), to the total of all participants’ compensation. Shares of the ESOP which have been allocated to employee accounts are charged to expense based on the fair value of the shares transferred and are treated as outstanding in determining earnings per share. Dividends paid on shares held by the ESOP are used to offset debt service on ESOP Loans. Dividends paid on shares held in participant accounts are utilized to allocate shares from the aggregate number of shares to be released, equal in value to those dividends, based on the closing price of Griffon common stock on the dividend payment date. Compensation expense under the ESOP was $2,878 in 2020 , $2,629 in 2019 and $9,532 in 2018, including an impact of $2,588 from the April 2018 special dividend. The cost of the shares held by the ESOP and not yet allocated to employees is reported as a reduction of Shareholders’ Equity. The fair value of the unallocated ESOP shares as of September 30, 2020 and 2019 based on the closing stock price of Griffon’s stock was $40,217 and $47,378 , respectively. The ESOP shares were as follows: At September 30, 2020 2019 Allocated shares 3,301,448 3,209,069 Unallocated shares 2,058,187 2,259,308 Total 5,359,635 5,468,377

INCOME TAXES

INCOME TAXES	12 Months Ended
	Sep. 30, 2020
Income Tax Disclosure [Abstract]
INCOME TAXES	INCOME TAXES On December 22, 2017, the U.S. enacted the Tax Cuts and Jobs Act (“TCJA”), which significantly changed U.S. tax law. The TCJA lowered the Company’s U.S. statutory federal income tax rate from 35% to 21% effective January 1, 2018, while also imposing a deemed repatriation tax on previously deferred foreign income. The TCJA also created a new minimum tax on certain foreign earnings, for which the Company has elected to record as a current period expense when incurred. The Company computed its income tax expense for the September 30, 2018 fiscal year using a blended Federal Tax Rate of 24.5% . The 21% Federal Tax Rate applies to the fiscal year ended September 30, 2019 and each year thereafter. In accordance with U.S. GAAP for income taxes, as well as SAB 118, the Company made a reasonable estimate of the impacts of the TCJA for the year ended September 30, 2018 and recorded a $20,587 benefit on the revaluation of deferred tax liabilities as a provisional amount for the re-measurement of deferred tax assets and liabilities, as well as an amount for deductible executive compensation expense, both of which have been reflected in the tax provision for 2018. SAB 118 allows for a measurement period of up to one year from the date of enactment to complete the Company’s accounting for the impacts of the TCJA. Our analysis under SAB 118 was completed in December 2018 and resulted in no material adjustments to the provision amounts recorded as of September 30, 2018. The Company recorded a provisional transition tax charge of $13,100 net of foreign tax credits for fiscal year 2018. The Company ultimately incurred a transition tax charge of $12,699 . Under the TCJA, the Company elected to pay the transition tax interest-free over eight years and at September 30, 2020 has $8,344 remaining on this liability. During fiscal 2020, the U.S. federal government enacted the Coronavirus Aid, Relief, and Economic Security Act (“CARES Act”). The CARES Act is an emergency economic stimulus package in response to the coronavirus outbreak which, among other things, contains numerous income tax provisions. The Company evaluated the impact of the legislation and determined that while there was an impact on the timing of certain tax payments, there is no material impact on the Company’s consolidated financial statements or related disclosures Income taxes have been based on the following components of Income before taxes from continuing operations: For the Years Ended September 30, 2020 2019 2018 Domestic $ 42,634 $ 49,723 $ 4,942 Non-U.S. 40,123 22,455 28,868 $ 82,757 $ 72,178 $ 33,810 Provision (benefit) for income taxes on income was comprised of the following from continuing operations: For the Years Ended September 30, 2020 2019 2018 Current $ 27,233 $ 28,778 $ 18,188 Deferred 2,095 (2,222 ) (17,633 ) Total $ 29,328 $ 26,556 $ 555 U.S. Federal $ 10,978 $ 14,160 $ (12,714 ) State and local 7,331 6,187 5,175 Non-U.S. 11,019 6,209 8,094 Total provision $ 29,328 $ 26,556 $ 555 Differences between the effective income tax rate applied to Income and the U.S. Federal income statutory rate from continuing operations were as follows: For the Years Ended September 30, 2020 2019 2018 U.S. Federal income tax provision (benefit) rate 21.0 % 21.0 % 24.5 % State and local taxes, net of Federal benefit 6.0 % 6.6 % 10.2 % Non-U.S. taxes - foreign permanent items and taxes 3.3 % 2.0 % 3.6 % Change in tax contingency reserves 0.1 % (0.7 )% (0.6 )% Impact of federal rate change on deferred tax balances — % — % (60.0 )% Tax Reform-Repatriation of Foreign Earnings and GILTI — % 1.0 % 61.6 % Change in valuation allowance (1.5 )% 3.3 % 13.4 % Other non-deductible/non-taxable items, net 1.4 % 3.1 % (5.2 )% Non-deductible officer's compensation 4.4 % 5.2 % 6.4 % Research and U.S. foreign tax credits 1.4 % (4.7 )% (39.4 )% Share based compensation — % 0.4 % (3.8 )% Other (0.7 )% (0.4 )% (9.1 )% Effective tax provision (benefit) rate 35.4 % 36.8 % 1.6 % The tax effect of temporary differences that give rise to future deferred tax assets and liabilities are as follows: At September 30, 2020 2019 Deferred tax assets: Bad debt reserves $ 3,980 $ 1,980 Inventory reserves 9,371 8,361 Deferred compensation (equity compensation and defined benefit plans) 18,904 16,544 Compensation benefits 5,499 5,186 Insurance reserve 1,918 1,873 Warranty reserve 3,981 2,896 Lease liabilities 43,045 — Net operating loss 9,618 11,077 Tax credits 7,031 9,373 Capital loss carryback 2,205 2,000 Interest — 5,250 Other reserves and accruals 6,094 3,738 111,646 68,278 Valuation allowance (9,824 ) (10,823 ) Total deferred tax assets 101,822 57,455 Deferred tax liabilities: Goodwill and intangibles (44,051 ) (42,477 ) Property, plant and equipment (48,172 ) (43,996 ) Right-of-use assets (41,747 ) — Other (634 ) (1,096 ) Total deferred tax liabilities (134,604 ) (87,569 ) Net deferred tax liabilities $ (32,782 ) $ (30,114 ) During the year ended September 30, 2020, the Company adopted ASU 2016-02 relating to Leases (Topic 842). Deferred tax assets and liabilities were recorded relating to the lease liabilities and the right of use assets recognized under this new standard. The Company adopted this update under the modified retrospective approach which required no adjustment to a prior period. At September 30, 2020 the corresponding deferred tax asset and liabilities were $43,045 and $41,747 , respectively. In 2020, the decrease in the valuation allowance of $999 is primarily the result of the expiration of foreign tax credits, partially offset by the generation and usage or non-usage of foreign tax credit generated during the year. The components of the net deferred tax liability, by balance sheet account, were as follows: At September 30, 2020 2019 Other assets $ 614 $ 137 Other liabilities (34,008 ) (31,141 ) Liabilities of discontinued operations 612 890 Net deferred liability $ (32,782 ) $ (30,114 ) At both September 30, 2020 and 2019 , Griffon has a policy election to indefinitely reinvest the undistributed earnings of foreign subsidiaries with operations outside the U.S. As of September 30, 2020 , we have approximately $100,102 of unremitted earnings of non-U.S. subsidiaries. The Company generates substantial cash flow in the U.S. and does not have a current need for the cash to be returned to the U.S. from the foreign entities. In the event these earnings are later remitted to the U.S., any estimated withholding tax on remittance of those earnings is expected to be immaterial to the income tax provision. At September 30, 2020 , Griffon had no loss carryforwards for U.S. tax purposes and $9,671 for non-U.S. tax purposes. At September 30, 2019 , Griffon had loss carryforwards for U.S. and non-U.S tax purposes of $5,419 and $7,413 , respectively. The non-U.S. loss carryforwards are available for carryforward indefinitely. At September 30, 2020 and 2019 , Griffon had interest expense carryforwards of $0 and $25,000 , respectively. The interest expense carryforward was utilized in September 30, 2020. At September 30, 2020 and 2019 , Griffon had state and local loss carryforwards of $124,191 and $127,354 , respectively, which expire in varying amounts through 2039 . At September 30, 2020 and 2019 , Griffon had federal tax credit carryforwards of $5,954 and $8,948 , respectively, which expire in varying amounts through 2035 . At September 30, 2020 and 2019, Griffon had capital loss carryovers for U.S. tax purposes of $10,500 and $9,524 , respectively, generated in the September 30, 2019 tax year. The carryover is available for three-year carryback or five-year carryforward. We believe it is more likely than not that the benefit from certain federal and state tax attributes will not be realized. In recognition of this risk, we have provided a valuation allowance as of September 30, 2020 and 2019 of $9,824 and $10,823 , respectively, on the deferred tax assets. As it becomes probable that the benefits of these attributes will be realized, the reversal of valuation allowance will be recognized as a reduction of income tax expense. If certain substantial changes in Griffon's ownership occur, there would be an annual limitation on the amount of carryforward(s) that can be utilized. Griffon files U.S. Federal, state and local tax returns, as well as applicable returns in Canada, Australia, U.K. and other non-U.S. jurisdictions. Griffon’s U.S. Federal income tax returns are no longer subject to income tax examination for years before 2015. Griffon's major U.S. state and other non-U.S. jurisdictions are no longer subject to income tax examinations for years before 2013. Various U.S. state and statutory tax audits are currently underway. The following is a roll forward of unrecognized tax benefits: Balance at September 30, 2018 $ 4,519 Additions based on tax positions related to the current year 117 Additions based on tax positions related to prior years (559 ) Lapse of Statutes (16 ) Balance at September 30, 2019 4,061 Additions based on tax positions related to the current year 125 Additions based on tax positions related to prior years 20 Reductions based on tax positions related to prior years (3 ) Lapse of Statutes (23 ) Balance at September 30, 2020 $ 4,180 If recognized, the amount of potential tax benefits that would impact Griffon’s effective tax rate is $909 . Griffon recognizes potential accrued interest and penalties related to unrecognized tax benefits in income tax expense. At September 30, 2020 and 2019 , the combined amount of accrued interest and penalties related to tax positions taken or to be taken on Griffon’s tax returns and recorded as part of the reserves for uncertain tax positions was $77 and $66 , respectively. Griffon cannot reasonably estimate the extent to which existing liabilities for uncertain tax positions may increase or decrease within the next twelve months as a result of the progression of ongoing tax audits or other events. Griffon believes that it has adequately provided for all open tax years by tax jurisdiction.

STOCKHOLDERS' EQUITY AND EQUITY

STOCKHOLDERS' EQUITY AND EQUITY COMPENSATION	12 Months Ended
	Sep. 30, 2020
Stockholders' Equity Note [Abstract]
STOCKHOLDERS’ EQUITY AND EQUITY COMPENSATION	STOCKHOLDERS’ EQUITY AND EQUITY COMPENSATION During 2020 , 2019 and 2018, the Company declared and paid cash dividends totaling $0.30 per share, $0.29 per share and $0.28 per share, respectively. In addition, on March 7, 2018, the Board of Directors declared a special cash dividend of $1.00 per share, totaling $38,073 and paid on April 16, 2018 to shareholders of record as of the close of business on March 29, 2018. The Company currently intends to pay dividends each quarter; however, payment of dividends is determined by the Board of Directors at its discretion based on various factors, and no assurance can be provided as to the payment of future dividends. Dividends paid on shares in the ESOP were used to offset ESOP loan payments and recorded as a reduction of debt service payments and compensation expense. A dividend payable was established for the holders of restricted shares; such dividends will be released upon vesting of the underlying restricted shares. At September, 30, 2020, accrued dividends were $3,535 . On November 12, 2020, the Board of Directors declared a cash dividend of $0.08 per share, payable on December 17, 2020 to shareholders of record as of the close of business on November 25, 2020. On August 18, 2020, the Company sold 8,000,000 shares of our common stock at a price of $21.50 per share through a public equity offering, for a total net proceeds of $163,830 , net of underwriting discounts, commissions and offering expenses. In addition, on August 21, 2020, pursuant to the exercise by the underwriters of their overallotment option, the underwriters purchased an additional 700,000 shares of common stock from the Company at a price of $21.50 , resulting in additional net proceeds to the Company of $14,335 . In total, the Company sold 8,700,000 shares of common stock at a price of $21.50 for a total net proceeds of $178,165 . The Company used a portion of the net proceeds to temporarily repay outstanding borrowings under its Credit Agreement. The Company intends to use the remainder of the proceeds for working capital and general corporate purposes, including to expand its current business through acquisitions of, or investments in, other businesses or products. On January 29, 2016, shareholders approved the Griffon Corporation 2016 Equity Incentive Plan ("Incentive Plan") under which awards of performance shares, performance units, stock options, stock appreciation rights, restricted shares, restricted stock units, deferred shares and other stock-based awards may be granted. On January 31, 2018, shareholders approved Amendment No. 1 to the Incentive Plan pursuant to which, among other things, 1,000,000 shares were added to the Incentive Plan; and on January 30, 2020, shareholders approved Amendment No. 2 to the Incentive Plan, pursuant to which 1,700,000 shares were added to the Incentive Plan. Options granted under the Incentive Plan may be either “incentive stock options” or nonqualified stock options, which generally expire ten years after the date of grant and are granted at an exercise price of not less than 100% of the fair market value at the date of grant. As of September 30, 2020, there are no stock options outstanding. The maximum number of shares of common stock available for award under the Incentive Plan is 5,050,000 ( 600,000 of which may be issued as incentive stock options), plus (i) any shares reserved for issuance under the 2011 Equity Incentive Plan as of the effective date of the Incentive Plan, and (ii) any shares of underlying awards outstanding on such effective date under the 2011 Incentive Plan that are canceled or forfeited. As of September 30, 2020 , 1,167,172 shares were available for grant. Compensation expense for restricted stock and restricted stock units ("RSUs") is recognized ratably over the required service period based on the fair value of the grant, calculated as the number of shares (or RSUs) granted multiplied by the stock price on date of grant, and for performance shares (or performance RSUs), the likelihood of achieving the performance criteria. Compensation expense for restricted stock granted to two senior executives is calculated as the maximum number of shares granted, upon achieving certain performance criteria, multiplied by the stock price as valued by a Monte Carlo Simulation Model. Compensation cost related to stock-based awards with graded vesting, generally over a period of three to four years , is recognized using the straight-line attribution method and recorded within Selling, general and administrative expenses. The following table summarizes the Company’s compensation expense relating to all stock-based compensation plans: For the Years Ended September 30, 2020 2019 2018 Restricted stock $ 14,702 $ 13,285 $ 10,078 ESOP 2,878 2,629 9,532 Total stock based compensation $ 17,580 $ 15,914 $ 19,610 In 2018, the ESOP compensation expense includes dividends paid on allocated shares in connection with the special cash dividend as mentioned above, of $1.00 per share paid on April 16, 2018 to shareholders of record as of the close of business on March 29, 2018. A summary of restricted stock activity, inclusive of restricted stock units, for 2020 is as follows: Shares Weighted Average Grant- Date Fair Value Unvested at September 30, 2019 3,713,573 $ 12.96 Granted 1,061,624 17.10 Vested (831,748 ) 21.51 Forfeited (257,859 ) 15.35 Unvested at September 30, 2020 3,685,590 14.30 The fair value of restricted stock which vested during 2020, 2019, and 2018 was $17,889 , $4,748 and $11,216 , respectively. Unrecognized compensation expense related to non-vested shares of restricted stock was $22,340 at September 30, 2020 and will be recognized over a weighted average vesting period of 2.3 years. At September 30, 2020 , a total of approximately 4,852,762 shares of Griffon’s authorized Common Stock were reserved for issuance in connection with stock compensation plans. During 2020, Griffon granted 1,061,624 shares of restricted stock and restricted stock units. This included 348,280 shares of restricted stock and restricted stock units, subject to certain performance conditions, with vesting periods of approximately three years , with a total fair value of $7,446 , or a weighted average fair value of $21.38 per share. This also included 53,344 of restricted shares granted to non-employee directors of Griffon with a vesting period of three years and a fair value of $1,170 , or a weighted average fair value of $21.93 per share. Furthermore, this included 660,000 shares of restricted stock granted to two senior executives with a vesting period of four years and a two year post-vesting holding period, subject to the achievement of certain absolute and relative performance conditions relating to the price of Griffon's common stock. So long as the minimum performance condition is attained, the amount of shares that can vest will range from 480,000 to 660,000 . The Monte Carlo Simulation model was chosen to value the two senior executive awards; The total fair value of these restricted shares using the Monte Carlo Simulation model is approximately $9,534 , or a weighted average fair value of $14.45 . On each of August 3, 2016 and August 1, 2018, Griffon’s Board of Directors authorized the repurchase of up to $50,000 of Griffon’s outstanding common stock. Under these share repurchase programs, the Company may purchase shares of its common stock, depending upon market conditions, in open market or privately negotiated transactions, including pursuant to a 10b5-1 plan. Shares repurchased are recorded at cost. During 2020, Griffon did no t purchase shares of common stock under these repurchase programs. At September 30, 2020 an aggregate of $57,955 remains under Griffon's Board authorized repurchase authorizations. During the year ended September 30, 2020 , 340,775 shares, with a market value of $7,409 , or $21.74 per share, were withheld to settle employee taxes due upon the vesting of restricted stock, and were added to treasury stock. Furthermore, during 2020, an additional 3,307 shares, with a market value of $70 , or $21.22 per share, were withheld from common stock issued upon the vesting of restricted stock units to settle employee taxes due upon vesting. On June 19, 2018, GS Direct, L.L.C., an affiliate of Goldman Sachs & Co. ("GS Direct") completed an underwritten secondary offering to sell 5,583,375 shares of Griffon's common stock, inclusive of the underwriters’ 30-day option to purchase additional shares. GS Direct’s original 10,000,000

COMMITMENTS AND CONTINGENT LIAB

COMMITMENTS AND CONTINGENT LIABILITIES	12 Months Ended
	Sep. 30, 2020
Commitments and Contingencies Disclosure [Abstract]
COMMITMENTS AND CONTINGENT LIABILITIES	COMMITMENTS AND CONTINGENT LIABILITIES Leases Griffon rents real property and equipment under operating leases expiring at various dates. Most of the real property leases have escalation clauses related to increases in real property taxes. Additionally, two Griffon subsidiaries have finance leases outstanding for real estate located in Troy, Ohio and Ocala, Florida. The leases mature in 2021 and 2025, respectively. The Ocala, Florida lease contains two five-year renewal options. Griffon also has various finance equipment leases. Refer to Note 22 - Leases for further information. Aggregate future maturities of lease payments for operating leases and finance leases as of September 30, 2020 are as follows (in thousands): Operating Leases Finance Leases 2021 $ 38,411 $ 4,282 2022 33,286 2,695 2023 25,599 2,375 2024 19,057 2,119 2025 16,334 2,074 2026 71,903 9,850 Total lease payments 204,590 23,395 Less: Imputed Interest (36,688 ) (4,704 ) Present value of lease liabilities $ 167,902 $ 18,691 Purchase Commitments Purchase obligations are generally for the purchase of goods and services in the ordinary course of business. Griffon uses blanket purchase orders to communicate expected requirements to certain vendors. Purchase obligations reflect those purchase orders where the commitment is considered to be firm. Amounts purchased under such commitments were $239,365 , $226,026 and $209,924 for the years ended September 30, 2020, 2019 and 2018, respectively. Purchase obligations that extend beyond 2020 are principally related to long-term contracts received from customers of Telephonics. Aggregate future minimum purchase obligations at September 30, 2020 are $377,388 in 2021, $9,748 in 2022, $12 in 2023, $0 in 2024 and $0 in 2025. Legal and environmental Peekskill Site. Lightron Corporation (“Lightron”), a wholly-owned subsidiary of Griffon, once conducted operations at a location in the Town of Cortlandt, New York, just outside the city of Peekskill, New York (the “Peekskill Site”) owned by ISC Properties, Inc. (“ISCP”), a wholly-owned subsidiary of Griffon. ISCP sold the Peekskill Site in November 1982. Subsequently, ISCP was advised by the Department of Environmental Conservation of New York State (the "DEC") that sampling at the Peekskill Site and in a creek near the Peekskill Site indicated concentrations of solvents and other chemicals common to prior plating operations by a Lightron subsidiary. In 1996, ISCP entered into a consent order with the DEC (the “Consent Order”), pursuant to which ISCP was required to perform a remedial investigation and prepare a feasibility study (the “Feasibility Study”). After completing the initial remedial investigation, ISCP conducted supplemental remedial investigations over the next several years, including soil vapor investigations, as required by the Consent Order. In April 2009, the DEC advised ISCP that both the DEC and the New York State Department of Health had reviewed and accepted an August 2007 Remedial Investigation Report and an Additional Data Collection Summary Report dated January 30, 2009. ISCP submitted to the DEC a draft Feasibility Study which was accepted and approved by the DEC in February 2011. ISCP satisfied its obligations under the Consent Order when DEC approved the Remedial Investigation and Feasibility Study for the Peekskill Site. In June 2011 the DEC issued a Record of Decision that set forth a Remedial Action Plan for the Peekskill Site that identified the specific remedies selected and responded to public comments. The cost of the remedy proposed by DEC in its Remedial Action Plan was approximately $10,000 . Following issuance of the Remedial Action Plan, the DEC implemented a portion of its plan, and also performed additional investigation for the presence of metals in soils and sediments downstream from the Peekskill Site. During this investigation metals were found to be present in sediments further downstream from the Peekskill site than previously detected. In August 2018, the DEC sent a letter to the United States Environmental Protection Agency (the “EPA”), in which the DEC requested that the Peekskill Site be nominated by the EPA for inclusion on the National Priorities List under CERCLA (the “NPL”). Based on the DEC’s request and an analysis by a consultant retained by the EPA, on May 15, 2019 the EPA added the Peekskill Site to the NPL and has since announced that it is performing a Remedial Investigation/Feasibility Study. On August 25, 2020, the EPA send a letter to several parties, including Lightron and ISCP, requesting that each such party inform the EPA as to whether it would be willing to enter into discussions regarding implementation of a Remedial Investigation/Feasibility Study (“RI/FS”). The EPA also sent a request for information to each party under Section 104(e) of CERCLA. Lightron and ISCP have informed the EPA that they are willing to participate in discussions regarding implementation of the RI/FS. Lightron and ISCP have also submitted responses to certain items contained in the Section 104(e) information request, with additional responses to follow. The current owner of the property, which acquired the Peekskill Site from ISCP in 1982 and has no relationship with Lightron or ISCP, has also informed the EPA that it is willing to discuss implementation of the RI/FS, and has also received, and submitted certain information in response to, a Section 104(e) information request. The EPA may decide to implement the RI/FS, on its own or through the use of consultants, may reach agreement with one or more parties to perform the RI/FS, or may offer to negotiate with one or more parties to accept a settlement addressing the potential liability of such parties for investigation and/or remediation at the Peekskill Site. Should the EPA implement the RI/FS, or perform further studies and/or subsequently remediate the site, without first reaching agreement with one or more relevant parties, the EPA would likely seek reimbursement for the costs incurred from such parties. Lightron has not engaged in any operations in over three decades. ISCP functioned solely as a real estate holding company, and has not held any real property in over three decades. Griffon does not acknowledge any responsibility to perform any investigation or remediation at the Peekskill Site. Union Fork and Hoe, Frankfort, NY site. The former Union Fork and Hoe property in Frankfort NY was acquired by AMES in 2006 as part of a larger acquisition, and has historic site contamination involving chlorinated solvents, petroleum hydrocarbons and metals. AMES entered into an Order on Consent with the New York State Department of Environmental Conservation (“DEC”). While the Order is without admission or finding of liability or acknowledgment that there has been a release of hazardous substances at the site, the Order required Ames to perform a remedial investigation of certain portions of the property and to recommend a remediation option. In 2018, Ames submitted a Feasibility Study recommending excavation of shallow soils for lead, arsenic and hydrocarbons in addition to deeper excavation for lead. DEC approved the selection of this remedy in 2019 by issuing a Record of Decision (“ROD”). Beginning in late 2019 and through June 2020, Ames completed the remediation required by the ROD and filed a Construction Completion Report, a Site Management Plan and an environmental easement with the DEC. While Ames was implementing the remediation required by the ROD, the DEC requested additional investigation of a small area on the site and of an area adjacent to the site perimeter. Ames investigated the on-site area and has submitted a workplan to remediate the limited contamination found as a result of this investigation. Ames has also submitted a workplan to investigate the areas adjacent to the site perimeter. AMES has a number of defenses to liability in this matter, including its rights under a previous Consent Judgment entered into between the DEC and a predecessor of AMES relating to the site. Ames’ insurer has accepted Ames’ claim for a substantial portion of the costs incurred and to be incurred for both the on-site and off-site activities. U.S. Government investigations and claims Defense contracts and subcontracts, including Griffon’s contracts and subcontracts, are subject to audit and review by various agencies and instrumentalities of the United States government, including among others, the Defense Contract Audit Agency, the Defense Criminal Investigative Service, and the Department of Justice which has responsibility for asserting claims on behalf of the U.S. Government. In general, departments and agencies of the U.S. Government have the authority to investigate various transactions and operations of Griffon, and the results of such investigations may lead to administrative, civil or criminal proceedings, the ultimate outcome of which could be fines, penalties, repayments or compensatory or treble damages. U.S. Government regulations provide that certain findings against a contractor may lead to suspension or debarment from future U.S. Government contracts or the loss of export privileges for a company or an operating division or subdivision. Suspension or debarment could have a material adverse effect on Telephonics because of its reliance on government contracts. General legal Griffon is subject to various laws and regulations relating to the protection of the environment and is a party to legal proceedings arising in the ordinary course of business. Management believes, based on facts presently known to it, that the resolution of the matters above and such other matters will not have a material adverse effect on Griffon’s consolidated financial position, results of operations or cash flows.

EARNINGS PER SHARE

EARNINGS PER SHARE	12 Months Ended
	Sep. 30, 2020
Earnings Per Share [Abstract]
EARNINGS PER SHARE	EARNINGS PER SHARE Basic EPS (and diluted EPS in periods when a loss exists) was calculated by dividing income available to common shareholders by the weighted average number of shares of common stock outstanding during the period. Diluted EPS was calculated by dividing income available to common shareholders by the weighted average number of shares of common stock outstanding plus additional common shares that could be issued in connection with stock based compensation. In August 2020, Griffon Corporation completed the Public Offering of 8,700,000 shares of our common stock at a price of $21.50 per share. Total proceeds, net of fees, were $178,165 . The following table is a reconciliation of the share amounts (in thousands) used in computing basic and diluted EPS for 2020, 2019 and 2018 : 2020 2019 2018 Common shares outstanding 56,130 46,806 45,675 Unallocated ESOP shares (2,058 ) (2,259 ) (2,477 ) Non-vested restricted stock (3,556 ) (3,420 ) (2,522 ) Impact of weighted average shares (7,928 ) (193 ) 329 Weighted average shares outstanding - basic 42,588 40,934 41,005 Incremental shares from stock based compensation 2,427 1,954 1,417 Weighted average shares outstanding - diluted 45,015 42,888 42,422 Anti-dilutive shares were not material. Shares of the ESOP that have been allocated to employee accounts are treated as outstanding in determining earnings per share.

RELATED PARTIES

RELATED PARTIES	12 Months Ended
	Sep. 30, 2020
Related Party Transactions [Abstract]
RELATED PARTIES	RELATED PARTIES On September 5, 2017, Griffon entered into an engagement letter with Goldman Sachs & Co. ("Goldman Sachs") pursuant to which Goldman Sachs agreed to act as Griffon’s financial advisor in connection with the exploration of strategic alternatives for Plastics. On November 15, 2017, Griffon signed an agreement to sell Plastics for approximately $465,000 to Berry. Under the terms of the engagement letter, upon the closing of the transaction a customary advisory fee was paid by Griffon to Goldman Sachs. Goldman Sachs acted as a joint lead manager and as an initial purchaser in connection with Griffon’s add-on offering of $275,000 aggregate principal amount of 5.25% senior notes due 2022 that closed on October 2, 2017, and received a customary fee upon closing of the offering. On June 19, 2018, GS Direct completed an underwritten secondary offering to sell 5,583,375 shares of Griffon's common stock, inclusive of the underwriters' 30-day option to purchase additional shares. GS Direct's initial 10,000,000

QUARTERLY FINANCIAL INFORMATION

QUARTERLY FINANCIAL INFORMATION (UNAUDITED)	12 Months Ended
	Sep. 30, 2020
Quarterly Financial Information Disclosure [Abstract]
QUARTERLY FINANCIAL INFORMATION (UNAUDITED)	QUARTERLY FINANCIAL INFORMATION (UNAUDITED) Quarterly results of continuing operations for 2020 and 2019 were as follows: Quarter ended Revenue Gross Profit Income from continuing operations Per Share - Basic Per Share - Diluted 2020 December 31, 2019 $ 548,438 $ 149,921 $ 10,612 $ 0.26 $ 0.24 March 31, 2020 566,350 152,032 895 0.02 0.02 June 30, 2020 632,061 165,003 21,831 0.52 0.50 September 30, 2020 660,673 174,470 20,091 0.44 0.41 $ 2,407,522 $ 641,426 $ 53,429 $ 1.25 $ 1.19 2019 December 31, 2018 $ 510,522 $ 139,780 $ 8,753 $ 0.21 $ 0.21 March 31, 2019 549,633 133,537 6,490 0.16 0.15 June 30, 2019 574,970 151,699 14,128 0.34 0.33 September 30, 2019 574,164 158,458 16,251 0.40 0.37 $ 2,209,289 $ 583,474 $ 45,622 $ 1.11 $ 1.06 Notes to Quarterly Financial Information (unaudited): • Earnings (loss) per share are computed independently for each quarter and year presented; as such the sum of the quarters may not be equal to the full year amounts. • 2020 Net income, and the related per share earnings, included, net of tax, restructuring charges of $4,148 , $3,005 , $1,224 and $3,488 for the first, second, third and fourth quarters, respectively, acquisition costs of $2,321 for the second quarter, loss from debt extinguishment $5,245 and $969 for the second and third quarters, respectively, benefit from the reversal of contingent consideration related to the Kelkay acquisition of $1,403 for the fourth quarter. The fourth quarter also includes a $15 and $24 tax benefit for acquisition costs and loss from debt extinguishment, respectively. • 2019 Net income, and the related per share earnings, included, net of tax, a benefit from the reversal of contingent consideration related to the Kelkay acquisition of $1,333 for the fourth quarter.

REPORTABLE SEGMENTS

REPORTABLE SEGMENTS	12 Months Ended
	Sep. 30, 2020
Segment Reporting [Abstract]
REPORTABLE SEGMENTS	REPORTABLE SEGMENTS Griffon conducts its operations through three reportable segments from continuing operations, as follows: • Consumer and Professional Products ("CPP") conducts its operations through AMES. Founded in 1774, AMES is the leading North American manufacturer and a global provider of branded consumer and professional tools and products for home storage and organization, landscaping, and enhancing outdoor lifestyles. CPP sells products globally through a portfolio of leading brands including True Temper, AMES, and ClosetMaid. • Home and Building Products ("HBP") conducts its operations through Clopay. Founded in 1964, Clopay is the largest manufacturer and marketer of garage doors and rolling steel doors in North America. Residential and commercial sectional garage doors are sold through professional dealers and leading home center retail chains throughout North America under the brands Clopay, Ideal, and Holmes. Rolling steel door and grille products designed for commercial, industrial, institutional, and retail use are sold under the CornellCookson brand. • Defense Electronics conducts its operations through Telephonics Corporation ("Telephonics"), founded in 1933, a globally recognized leading provider of highly sophisticated intelligence, surveillance and communications solutions for defense, aerospace and commercial customers. Information on Griffon’s reportable segments from continuing operations is as follows: For the Years Ended September 30, REVENUE 2020 2019 2018 Consumer and Professional Products $ 1,139,233 $ 1,000,608 $ 953,612 Home and Building Products 927,313 873,640 697,969 Defense Electronics 340,976 335,041 326,337 Total consolidated net sales $ 2,407,522 $ 2,209,289 $ 1,977,918 Griffon evaluates performance and allocates resources based on each segment's operating results from continuing operations before interest income and expense, income taxes, depreciation and amortization, unallocated amounts (primarily corporate overhead), restructuring charges, loss on debt extinguishment and acquisition related expenses, as well as other items that may affect comparability, as applicable (“Segment Adjusted EBITDA”). The following table provides a reconciliation of Segment Adjusted EBITDA to Income before taxes and discontinued operations: For the Years Ended September 30, 2020 2019 2018 Segment Adjusted EBITDA: Consumer and Professional Products $ 104,053 $ 90,677 $ 77,061 Home and Building Products 153,631 120,161 100,339 Defense Electronics 25,228 35,104 36,063 Segment Adjusted EBITDA 282,912 245,942 213,463 Unallocated amounts, excluding depreciation (47,013 ) (46,302 ) (45,343 ) Adjusted EBITDA 235,899 199,640 168,120 Net interest expense (65,791 ) (67,260 ) (63,871 ) Depreciation and amortization (62,409 ) (61,848 ) (55,803 ) Restructuring charges (15,790 ) — — Loss from debt extinguishment (7,925 ) — — Acquisition contingent consideration 1,733 1,646 — Acquisition costs (2,960 ) — (7,597 ) Special dividend charges — — (3,220 ) Cost of life insurance benefit — — (2,614 ) Secondary equity offering costs — — (1,205 ) Income before taxes from continuing operations $ 82,757 $ 72,178 $ 33,810 For the Years Ended September 30, DEPRECIATION and AMORTIZATION 2020 2019 2018 Segment: Consumer and Professional Products $ 32,788 $ 32,289 $ 30,816 Home and Building Products 18,361 18,334 13,717 Defense Electronics 10,645 10,667 10,801 Total segment depreciation and amortization 61,794 61,290 55,334 Corporate 615 558 469 Total consolidated depreciation and amortization $ 62,409 $ 61,848 $ 55,803 CAPITAL EXPENDITURES Segment: Consumer and Professional Products $ 23,321 $ 17,828 $ 23,040 Home and Building Products 17,499 16,498 13,547 Defense Electronics 7,830 10,492 10,941 Total segment 48,650 44,818 47,528 Corporate 348 543 2,610 Total consolidated capital expenditures $ 48,998 $ 45,361 $ 50,138 ASSETS At September 30, 2020 At September 30, 2019 Segment assets: Consumer and Professional Products $ 1,262,705 $ 1,070,510 Home and Building Products 606,785 571,216 Defense Electronics 329,128 347,575 Total segment assets 2,198,618 1,989,301 Corporate 248,902 82,429 Total continuing assets 2,447,520 2,071,730 Assets of discontinued operations 8,497 3,209 Consolidated total $ 2,456,017 $ 2,074,939 Disaggregation of Revenue Revenue from contracts with customers is disaggregated by end markets, segments and geographic location, as it more accurately depicts the nature and amount of the Company’s revenue. For the Year Ended September 30, 2020 For the Year Ended September 30, 2019 Residential repair and remodel $ 173,859 $ 140,369 Retail 575,947 528,279 Residential new construction 59,907 58,709 Industrial 40,285 45,129 International excluding North America 289,235 228,122 Total Consumer and Professional Products 1,139,233 1,000,608 Residential repair and remodel 467,112 439,287 Commercial construction 354,916 335,339 Residential new construction 105,285 99,014 Total Home and Building Products 927,313 873,640 U.S. Government 222,537 211,405 International 100,623 105,705 Commercial 17,816 17,931 Total Defense Electronics 340,976 335,041 Total Consolidated Revenue $ 2,407,522 $ 2,209,289 The following table presents revenue disaggregated by geography based on the location of the Company's customer: For the Year Ended September 30, 2020 Revenue by Geographic Area - Destination Consumer and Professional Products Home and Building Products Defense Electronics Total United States $ 769,100 $ 877,115 $ 234,382 $ 1,880,597 Europe 85,339 130 38,353 123,822 Canada 74,072 38,662 12,043 124,777 Australia 203,012 — 1,882 204,894 All other countries 7,710 11,406 54,316 73,432 Consolidated revenue $ 1,139,233 $ 927,313 $ 340,976 $ 2,407,522 For the Year Ended September 30, 2019 Revenue by Geographic Area - Destination Consumer and Professional Products Home and Building Products Defense Electronics Total United States $ 690,772 $ 820,396 $ 226,095 $ 1,737,263 Europe 63,284 109 36,915 100,308 Canada 72,327 39,472 10,568 122,367 Australia 165,291 16 3,712 169,019 All other countries 8,934 13,647 57,751 80,332 Consolidated revenue $ 1,000,608 $ 873,640 $ 335,041 $ 2,209,289 As a percentage of segment revenue, CPP sales to The Home Depot approximated 27% , 28% and 29% in 2020 , 2019 and 2018 , respectively; HBP sales to The Home Depot approximated 12% , 13% and 16% in 2020 , 2019 and 2018 , respectively; and DE aggregate sales to the United States Government and its agencies approximated 69% , 63% and 62% in 2020 , 2019 and 2018 , respectively. As a percentage of Griffon's consolidated revenue from continuing operations, CPP sales to The Home Depot approximated 13% , in both 2020 and 2019, and 14% in 2018; HBP sales to The Home Depot approximated 5% in both 2020 and 2019, and 6% in 2018; and DE aggregate sales to the United States Government and its agencies approximated 9% in 2020, and 10% in both 2019 and 2018.

OTHER INCOME (EXPENSE)

OTHER INCOME (EXPENSE)	12 Months Ended
	Sep. 30, 2020
Other Income and Expenses [Abstract]
OTHER INCOME (EXPENSE)	OTHER INCOME (EXPENSE) For the year ended September 30, 2020 , 2019 and 2018, Other income (expense) from continuing operations of $1,445 , $3,127 and $4,880 , respectively, includes $915 , $438 and $200 , respectively, of net currency exchange transaction losses from receivables and payables held in non-functional currencies, $184 , $(40) and $1,184 , respectively, of net gains or (losses) on investments, and $1,559 and $3,148 and $3,649 , respectively, of net periodic benefit plan income. Additionally, in 2020 , Other income (expense) also includes a one-time technology recognition award for $700

OTHER COMPREHENSIVE INCOME (LOS

OTHER COMPREHENSIVE INCOME (LOSS)	12 Months Ended
	Sep. 30, 2020
Other Comprehensive Income (Loss), Net of Tax [Abstract]
OTHER COMPREHENSIVE INCOME (LOSS)	OTHER COMPREHENSIVE INCOME (LOSS) The amounts recognized in other comprehensive income (loss) were as follows: Years Ended September 30, 2020 2019 2018 Pre-tax Tax Net of tax Pre-tax Tax Net of tax Pre-tax Tax Net of tax Foreign currency translation adjustments $ 5,601 $ — $ 5,601 $ (8,460 ) $ — $ (8,460 ) $ 9,403 $ — $ 9,403 Pension and other defined benefit plans (14,955 ) 3,171 (11,784 ) (30,581 ) 7,526 (23,055 ) 24,081 (7,700 ) 16,381 Cash flow hedge 10 (3 ) 7 (413 ) 124 (289 ) 900 (315 ) 585 Total other comprehensive income (loss) $ (9,344 ) $ 3,168 $ (6,176 ) $ (39,454 ) $ 7,650 $ (31,804 ) $ 34,384 $ (8,015 ) $ 26,369 The components of Accumulated other comprehensive income (loss) are as follows: At September 30, 2020 2019 Foreign currency translation $ (25,683 ) $ (31,284 ) Pension and other defined benefit plans (46,598 ) (34,814 ) Cash flow hedge 189 182 Total $ (72,092 ) $ (65,916 ) Total comprehensive income (loss) were as follows: For the Years Ended September 30, 2020 2019 2018 Net income $ 53,429 $ 37,287 $ 125,678 Other comprehensive income (loss), net of taxes (6,176 ) (31,804 ) 26,369 Comprehensive income (loss) $ 47,253 $ 5,483 $ 152,047 Amounts reclassified from accumulated other comprehensive income (loss) to income (loss) were as follows: For the Years Ended September 30, Gain (Loss) 2020 2019 2018 Pension amortization $ (4,182 ) $ (902 ) $ (1,397 ) Cash flow hedges (2,163 ) 1,361 657 Total before tax (6,345 ) 459 (740 ) Tax 1,332 (96 ) 155 Net of tax $ (5,013 ) $ 363 $ (585 )

LEASES

LEASES	12 Months Ended
	Sep. 30, 2020
Leases [Abstract]
LEASES	LEASES In February 2016, the FASB issued an Accounting Standards Update (ASU 2016-02) related to the accounting and financial statement presentation for leases. This new guidance requires a lessee to recognize right-of-use ("ROU") assets and lease liabilities on the balance sheet, with an election to exempt leases with a term of twelve months or less. The Company adopted the requirements of the new standard as of October 1, 2019 and applied the modified retrospective approach, whereby the cumulative effect of adoption is recognized as of the date of adoption and comparative prior periods are not retrospectively adjusted. As a result, upon adoption, we have recognized ROU assets of $163,552 and lease liabilities of $163,676 associated with our operating leases. The standard had no material impact to retained earnings or on our Consolidated Statements of Income or Consolidated Statements of Cash Flows. The Company has elected the package of practical expedients permitted under the transition guidance within the new standard, which among other things, allows us to carry forward the historical lease classification. We also elected a practical expedient to determine the reasonably certain lease term. The Company determines if an arrangement is a lease at inception. The ROU assets and short and long-term liabilities associated with our operating leases are shown as separate line items on our Condensed Consolidated Balance Sheets. Finance leases are included in property, plant, and equipment, net, other accrued liabilities, and other non-current liabilities. The Company's finance leases are immaterial. ROU assets, along with any other related long-lived assets, are periodically evaluated for impairment. In connection with the Company's restructuring activities, during the year ended September 30, 2020, a $1,968 impairment charge was recorded related to a facility’s operating lease as well as $671 and of leasehold improvements made to the leased facility that have no recoverable value. See Note 9, Restructuring Charges. ROU assets represent our right to use an underlying asset for the lease term and lease liabilities represent our obligation to make lease payments arising from the lease. ROU assets and liabilities are recognized at the lease commencement date based on the present value of lease payments over the lease term. As most of our leases do not provide an implicit rate, we use our incremental borrowing rate based on the information available at the commencement date in determining the present value of lease payments. We use the implicit rate when readily determinable. For leases existing as of October 1, 2019, we have elected to use the remaining lease term as of the adoption date in determining the incremental borrowing rate. Our determination of the lease term may include options to extend or terminate the lease when it is reasonably certain that we will exercise that option. For operating leases, fixed lease payments are recognized as operating lease cost on a straight-line basis over the lease term. For finance leases and impaired operating leases, the ROU asset is depreciated on a straight-line basis over the remaining lease term, along with recognition of interest expense associated with accretion of the lease liability. For leases with a lease term of 12 months or less (a "Short-term" lease), any fixed lease payments are recognized on a straight-line basis over such term, and are not recognized on the Condensed Consolidated Balance Sheets. Variable lease cost for both operating and finance leases, if any, is recognized as incurred. The Company has lease agreements that contain both lease and non-lease components. For real estate leases, we account for lease components together with non-lease components (e.g., common-area maintenance). Components of operating lease costs are as follows: For the Year Ended September 30, 2020 Fixed (a) $ 38,554 Variable (a), (b) 7,822 Short-term (b) 5,606 Total $ 51,982 (a) Primarily related to common-area maintenance and property taxes. (b) Not recorded on the balance sheet. Fixed rent expense for all operating leases totaled approximately $37,068 and $35,726 in 2019 and 2018, respectively. Supplemental cash flow information were as follows: For the Year Ended September 30, 2020 Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows from operating leases $ 48,141 Financing cash flows from finance leases 4,122 Total $ 52,263 Supplemental Condensed Consolidated Balance Sheet information related to leases were as follows: At September 30, 2020 Operating Leases: Right of use assets: Operating right-of-use assets $ 161,627 Lease Liabilities: Current portion of operating lease liabilities $ 31,848 Long-term operating lease liabilities 136,054 Total operating lease liabilities $ 167,902 Finance Leases: Right of use assets: Property, plant and equipment, net (1) $ 18,774 Lease Liabilities: Notes payable and current portion of long-term debt $ 3,352 Long-term debt, net 15,339 Total financing lease liabilities $ 18,691 (1) Finance lease assets are recorded net of accumulated depreciation of $2,383 . Two Griffon subsidiaries have finance leases outstanding for real estate located in Troy, Ohio and Ocala, Florida. The leases mature in 2021 and 2025, respectively, and bear interest at fixed rates of approximately 5.0% and 5.6% , respectively. The Troy, Ohio lease is secured by a mortgage on the real estate and is guaranteed by Griffon. The Ocala, Florida lease contains two five-year renewal options. As of September 30, 2020 and 2019, $17,188 and $4,333 , respectively, was outstanding, net of issuance costs. The remaining lease liability balance relates to finance equipment leases. Finance leases included in the consolidated balance sheet at September 30, 2019 , under Property, plant and equipment, net totaled $6,546 . In 2019 and 2018, Depreciation expense was $3,967 , and $3,514 , respectively. The aggregate future maturities of lease payments for operating leases and finance leases as of September 30, 2020 are as follows (in thousands): Operating Leases Finance Leases 2021 $ 38,411 $ 4,282 2022 33,286 2,695 2023 25,599 2,375 2024 19,057 2,119 2025 16,334 2,074 2026 71,903 9,850 Total lease payments 204,590 23,395 Less: Imputed Interest (36,688 ) (4,704 ) Present value of lease liabilities $ 167,902 $ 18,691 Average lease terms and discount rates were as follows: September 30, 2020 Weighted-average remaining lease term (years) Operating Leases 8.3 Finance Leases 8.5 Weighted-average discount rate Operating Leases 4.38 % Finance Leases 5.51 %
LEASES	LEASES In February 2016, the FASB issued an Accounting Standards Update (ASU 2016-02) related to the accounting and financial statement presentation for leases. This new guidance requires a lessee to recognize right-of-use ("ROU") assets and lease liabilities on the balance sheet, with an election to exempt leases with a term of twelve months or less. The Company adopted the requirements of the new standard as of October 1, 2019 and applied the modified retrospective approach, whereby the cumulative effect of adoption is recognized as of the date of adoption and comparative prior periods are not retrospectively adjusted. As a result, upon adoption, we have recognized ROU assets of $163,552 and lease liabilities of $163,676 associated with our operating leases. The standard had no material impact to retained earnings or on our Consolidated Statements of Income or Consolidated Statements of Cash Flows. The Company has elected the package of practical expedients permitted under the transition guidance within the new standard, which among other things, allows us to carry forward the historical lease classification. We also elected a practical expedient to determine the reasonably certain lease term. The Company determines if an arrangement is a lease at inception. The ROU assets and short and long-term liabilities associated with our operating leases are shown as separate line items on our Condensed Consolidated Balance Sheets. Finance leases are included in property, plant, and equipment, net, other accrued liabilities, and other non-current liabilities. The Company's finance leases are immaterial. ROU assets, along with any other related long-lived assets, are periodically evaluated for impairment. In connection with the Company's restructuring activities, during the year ended September 30, 2020, a $1,968 impairment charge was recorded related to a facility’s operating lease as well as $671 and of leasehold improvements made to the leased facility that have no recoverable value. See Note 9, Restructuring Charges. ROU assets represent our right to use an underlying asset for the lease term and lease liabilities represent our obligation to make lease payments arising from the lease. ROU assets and liabilities are recognized at the lease commencement date based on the present value of lease payments over the lease term. As most of our leases do not provide an implicit rate, we use our incremental borrowing rate based on the information available at the commencement date in determining the present value of lease payments. We use the implicit rate when readily determinable. For leases existing as of October 1, 2019, we have elected to use the remaining lease term as of the adoption date in determining the incremental borrowing rate. Our determination of the lease term may include options to extend or terminate the lease when it is reasonably certain that we will exercise that option. For operating leases, fixed lease payments are recognized as operating lease cost on a straight-line basis over the lease term. For finance leases and impaired operating leases, the ROU asset is depreciated on a straight-line basis over the remaining lease term, along with recognition of interest expense associated with accretion of the lease liability. For leases with a lease term of 12 months or less (a "Short-term" lease), any fixed lease payments are recognized on a straight-line basis over such term, and are not recognized on the Condensed Consolidated Balance Sheets. Variable lease cost for both operating and finance leases, if any, is recognized as incurred. The Company has lease agreements that contain both lease and non-lease components. For real estate leases, we account for lease components together with non-lease components (e.g., common-area maintenance). Components of operating lease costs are as follows: For the Year Ended September 30, 2020 Fixed (a) $ 38,554 Variable (a), (b) 7,822 Short-term (b) 5,606 Total $ 51,982 (a) Primarily related to common-area maintenance and property taxes. (b) Not recorded on the balance sheet. Fixed rent expense for all operating leases totaled approximately $37,068 and $35,726 in 2019 and 2018, respectively. Supplemental cash flow information were as follows: For the Year Ended September 30, 2020 Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows from operating leases $ 48,141 Financing cash flows from finance leases 4,122 Total $ 52,263 Supplemental Condensed Consolidated Balance Sheet information related to leases were as follows: At September 30, 2020 Operating Leases: Right of use assets: Operating right-of-use assets $ 161,627 Lease Liabilities: Current portion of operating lease liabilities $ 31,848 Long-term operating lease liabilities 136,054 Total operating lease liabilities $ 167,902 Finance Leases: Right of use assets: Property, plant and equipment, net (1) $ 18,774 Lease Liabilities: Notes payable and current portion of long-term debt $ 3,352 Long-term debt, net 15,339 Total financing lease liabilities $ 18,691 (1) Finance lease assets are recorded net of accumulated depreciation of $2,383 . Two Griffon subsidiaries have finance leases outstanding for real estate located in Troy, Ohio and Ocala, Florida. The leases mature in 2021 and 2025, respectively, and bear interest at fixed rates of approximately 5.0% and 5.6% , respectively. The Troy, Ohio lease is secured by a mortgage on the real estate and is guaranteed by Griffon. The Ocala, Florida lease contains two five-year renewal options. As of September 30, 2020 and 2019, $17,188 and $4,333 , respectively, was outstanding, net of issuance costs. The remaining lease liability balance relates to finance equipment leases. Finance leases included in the consolidated balance sheet at September 30, 2019 , under Property, plant and equipment, net totaled $6,546 . In 2019 and 2018, Depreciation expense was $3,967 , and $3,514 , respectively. The aggregate future maturities of lease payments for operating leases and finance leases as of September 30, 2020 are as follows (in thousands): Operating Leases Finance Leases 2021 $ 38,411 $ 4,282 2022 33,286 2,695 2023 25,599 2,375 2024 19,057 2,119 2025 16,334 2,074 2026 71,903 9,850 Total lease payments 204,590 23,395 Less: Imputed Interest (36,688 ) (4,704 ) Present value of lease liabilities $ 167,902 $ 18,691 Average lease terms and discount rates were as follows: September 30, 2020 Weighted-average remaining lease term (years) Operating Leases 8.3 Finance Leases 8.5 Weighted-average discount rate Operating Leases 4.38 % Finance Leases 5.51 %

CONSOLIDATING GUARANTOR AND NON

CONSOLIDATING GUARANTOR AND NON-GUARANTOR FINANCIAL INFORMATION	12 Months Ended
	Sep. 30, 2020
Consolidating Guarantor And Non Guarantor Financial Information [Abstract]
CONSOLIDATING GUARANTOR AND NON-GUARANTOR FINANCIAL INFORMATION	CONSOLIDATING GUARANTOR AND NON-GUARANTOR FINANCIAL INFORMATION Griffon’s Senior Notes are fully and unconditionally guaranteed, jointly and severally, by Clopay Corporation, Telephonics Corporation, The AMES Companies, Inc., ATT Southern LLC, Clopay Ames Holding Corp., ClosetMaid, LLC, CornellCookson, LLC and Cornell Real Estate Holdings, LLC. all of which are indirectly 100% owned by Griffon. In accordance with Rule 3-10 of Regulation S-X promulgated under the Securities Act, presented below are condensed consolidating financial information as of September 30, 2020 and 2019, and for the years ended September 30, 2020 , 2019 and 2018. The financial information may not necessarily be indicative of results of operations or financial position had the guarantor companies or non-guarantor companies operated as independent entities. The guarantor companies and the non-guarantor companies include the consolidated financial results of their wholly owned subsidiaries accounted for under the equity method. The indenture relating to the Senior Notes (the “Indenture”) contain terms providing that, under certain limited circumstances, a guarantor will be released from its obligations to guarantee the Senior Notes. These circumstances include (i) a sale of at least a majority of the stock, or all or substantially all the assets, of the subsidiary guarantor as permitted by the Indenture; (ii) a public equity offering of a subsidiary guarantor that qualifies as a “Minority Business” as defined in the Indenture (generally, a business the EBITDA of which constitutes less than 50% of the segment adjusted EBITDA of the Company for the most recently ended four fiscal quarters), and that meets certain other specified conditions as set forth in the Indenture; (iii) the designation of a guarantor as an “unrestricted subsidiary” as defined in the Indenture, in compliance with the terms of the Indenture; (iv) Griffon exercising its right to defease the Senior Notes, or to otherwise discharge its obligations under the Indenture, in each case in accordance with the terms of the Indenture; and (v) upon obtaining the requisite consent of the holders of the Senior Notes. CONDENSED CONSOLIDATING BALANCE SHEETS At September 30, 2020 Parent Company Guarantor Companies Non-Guarantor Companies Elimination Consolidation CURRENT ASSETS Cash and equivalents $ 125,353 $ 35,685 $ 57,051 $ — $ 218,089 Accounts receivable, net of allowances — 293,943 54,181 — 348,124 Contract assets, net of progress payments — 80,572 3,854 — 84,426 Inventories — 347,473 66,352 — 413,825 Prepaid and other current assets 14,650 25,974 6,273 — 46,897 Assets of discontinued operations — — 2,091 — 2,091 Total Current Assets 140,003 783,647 189,802 — 1,113,452 PROPERTY, PLANT AND EQUIPMENT, net 1,182 296,082 46,700 — 343,964 OPERATING LEASE RIGHT-OF-USE ASSETS 9,209 129,813 22,605 — 161,627 GOODWILL — 377,060 65,583 — 442,643 INTANGIBLE ASSETS, net 93 217,317 137,618 — 355,028 INTERCOMPANY RECEIVABLE 568,124 704,415 257,013 (1,529,552 ) — EQUITY INVESTMENTS IN SUBSIDIARIES 1,724,821 784,644 3,176,855 (5,686,320 ) — OTHER ASSETS 12,585 25,953 (5,641 ) — 32,897 ASSETS OF DISCONTINUED OPERATIONS — — 6,406 — 6,406 Total Assets $ 2,456,017 $ 3,318,931 $ 3,896,941 $ (7,215,872 ) $ 2,456,017 CURRENT LIABILITIES Notes payable and current portion of long-term debt $ — $ 2,855 $ 7,067 $ — $ 9,922 Accounts payable and accrued liabilities 37,281 276,580 89,818 — 403,679 Current portion of operating lease liabilities 1,849 24,436 5,563 — 31,848 Liabilities of discontinued operations — — 3,797 — 3,797 Total Current Liabilities 39,130 303,871 106,245 — 449,246 LONG-TERM DEBT, net 995,636 15,992 25,414 — 1,037,042 LONG-TERM OPERATING LEASE LIABILITIES 8,415 110,061 17,578 — 136,054 INTERCOMPANY PAYABLES 683,076 397,846 459,599 (1,540,521 ) — OTHER LIABILITIES 29,609 85,731 11,170 — 126,510 LIABILITIES OF DISCONTINUED OPERATIONS — — 7,014 — 7,014 Total Liabilities 1,755,866 913,501 627,020 (1,540,521 ) 1,755,866 SHAREHOLDERS’ EQUITY 700,151 2,405,430 3,269,921 (5,675,351 ) 700,151 Total Liabilities and Shareholders’ Equity $ 2,456,017 $ 3,318,931 $ 3,896,941 $ (7,215,872 ) $ 2,456,017 CONDENSED CONSOLIDATING BALANCE SHEETS At September 30, 2019 Parent Company Guarantor Companies Non-Guarantor Companies Elimination Consolidation CURRENT ASSETS Cash and equivalents 1,649 25,217 45,511 — 72,377 Accounts receivable, net of allowances — 225,870 38,580 — 264,450 Contract assets, net of progress payments — 104,109 1,002 — 105,111 Inventories, net — 372,581 69,540 — 442,121 Prepaid and other current assets 8,238 25,610 6,951 — 40,799 Assets of discontinued operations — — 321 — 321 Total Current Assets 9,887 753,387 161,905 — 925,179 PROPERTY, PLANT AND EQUIPMENT, net 1,184 289,282 46,860 — 337,326 GOODWILL — 375,734 61,333 — 437,067 INTANGIBLE ASSETS, net 93 224,275 132,271 — 356,639 INTERCOMPANY RECEIVABLE 5,834 881,110 75,684 (962,628 ) — EQUITY INVESTMENTS IN SUBSIDIARIES 1,628,031 581,438 3,233,038 (5,442,507 ) — OTHER ASSETS 8,182 10,010 (2,352 ) — 15,840 ASSETS OF DISCONTINUED OPERATIONS — — 2,888 — 2,888 Total Assets 1,653,211 3,115,236 3,711,627 (6,405,135 ) 2,074,939 CURRENT LIABILITIES Notes payable and current portion of long-term debt — 3,075 7,450 — 10,525 Accounts payable and accrued liabilities 41,796 265,055 68,390 — 375,241 Liabilities of discontinued operations — — 4,333 — 4,333 Total Current Liabilities 41,796 268,130 80,173 — 390,099 LONG-TERM DEBT, net 1,040,449 3,119 50,181 — 1,093,749 INTERCOMPANY PAYABLES 71,634 466,792 444,557 (982,983 ) — OTHER LIABILITIES 21,569 73,411 15,017 — 109,997 LIABILITIES OF DISCONTINUED OPERATIONS — — 3,331 — 3,331 Total Liabilities 1,175,448 811,452 593,259 (982,983 ) 1,597,176 SHAREHOLDERS’ EQUITY 477,763 2,303,784 3,118,368 (5,422,152 ) 477,763 Total Liabilities and Shareholders’ Equity 1,653,211 3,115,236 3,711,627 (6,405,135 ) 2,074,939 CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME (LOSS) For the Year Ended September 30, 2020 Parent Company Guarantor Companies Non-Guarantor Companies Elimination Consolidation Revenue $ — $ 1,938,972 $ 507,621 $ (39,071 ) $ 2,407,522 Cost of goods and services — 1,450,924 355,696 (40,524 ) 1,766,096 Gross profit — 488,048 151,925 1,453 641,426 Selling, general and administrative expenses 24,876 357,901 103,991 (370 ) 486,398 Income (loss) from operations (24,876 ) 130,147 47,934 1,823 155,028 Other income (expense) Interest income (expense), net (27,129 ) (38,301 ) (361 ) — (65,791 ) Loss on extinguishment of debt (7,925 ) — — — (7,925 ) Other, net (523 ) (7,946 ) 11,762 (1,848 ) 1,445 Total other income (expense) (35,577 ) (46,247 ) 11,401 (1,848 ) (72,271 ) Income (loss) before taxes (60,453 ) 83,900 59,335 (25 ) 82,757 Provision (benefit) for income taxes (11,907 ) 25,445 15,788 2 29,328 Income (loss) before equity in net income of subsidiaries (48,546 ) 58,455 43,547 (27 ) 53,429 Equity in net income (loss) of subsidiaries 101,975 43,505 58,455 (203,935 ) — Net income (loss) $ 53,429 $ 101,960 $ 102,002 $ (203,962 ) $ 53,429 Comprehensive income (loss) $ 47,253 $ 101,960 $ 102,002 $ (203,962 ) $ 47,253 CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME (LOSS) For the Year Ended September 30, 2019 Parent Company Guarantor Companies Non-Guarantor Companies Elimination Consolidation Revenue $ — $ 1,808,824 $ 437,542 $ (37,077 ) $ 2,209,289 Cost of goods and services — 1,353,663 310,707 (38,555 ) 1,625,815 Gross profit — 455,161 126,835 1,478 583,474 Selling, general and administrative expenses 22,566 327,306 97,661 (370 ) 447,163 Income (loss) from operations (22,566 ) 127,855 29,174 1,848 136,311 Other income (expense) Interest income (expense), net (27,883 ) (39,288 ) (89 ) — (67,260 ) Other, net (778 ) (17,699 ) 23,452 (1,848 ) 3,127 Total other income (expense) (28,661 ) (56,987 ) 23,363 (1,848 ) (64,133 ) Income (loss) before taxes (51,227 ) 70,868 52,537 — 72,178 Provision (benefit) for income taxes (7,425 ) 20,534 13,447 — 26,556 Income (loss) before equity in net income of subsidiaries (43,802 ) 50,334 39,090 — 45,622 Equity in net income (loss) of subsidiaries 81,089 44,303 50,334 (175,726 ) — Income (loss) from continuing operations 37,287 94,637 89,424 (175,726 ) 45,622 Income (loss) from operations of discontinued businesses — — (11,050 ) — (11,050 ) Provision (benefit) from income taxes — — (2,715 ) — (2,715 ) Income (loss) from discontinued operations — — (8,335 ) — (8,335 ) Net Income (loss) $ 37,287 $ 94,637 $ 81,089 $ (175,726 ) $ 37,287 Comprehensive income (loss) $ 5,483 $ 87,851 $ 87,875 $ (175,726 ) $ 5,483 CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME (LOSS) For the Year Ended September 30, 2018 Parent Company Guarantor Companies Non-Guarantor Companies Elimination Consolidation Revenue $ — $ 1,638,792 $ 367,149 $ (28,023 ) $ 1,977,918 Cost of goods and services — 1,250,261 245,687 (29,348 ) 1,466,600 Gross profit — 388,531 121,462 1,325 511,318 Selling, general and administrative expenses 37,540 290,475 90,872 (370 ) 418,517 Income (loss) from operations (37,540 ) 98,056 30,590 1,695 92,801 Other income (expense) Interest income (expense), net (23,911 ) (31,913 ) (8,047 ) — (63,871 ) Other, net (7,666 ) 125,531 (111,248 ) (1,737 ) 4,880 Total other income (expense) (31,577 ) 93,618 (119,295 ) (1,737 ) (58,991 ) Income (loss) before taxes from continuing operations (69,117 ) 191,674 (88,705 ) (42 ) 33,810 Provision (benefit) for income taxes (17,692 ) 9,546 8,743 (42 ) 555 Income (loss) before equity in net income of subsidiaries (51,425 ) 182,128 (97,448 ) — 33,255 Equity in net income (loss) of subsidiaries 177,103 (151,864 ) 182,128 (207,367 ) — Income (loss) from continuing operations 125,678 30,264 84,680 (207,367 ) 33,255 Income from operations of discontinued businesses — 119,981 — — 119,981 Provision (benefit) from income taxes — 27,558 — — 27,558 Loss from discontinued operations — 92,423 — — 92,423 Net income (loss) $ 125,678 $ 122,687 $ 84,680 $ (207,367 ) $ 125,678 Comprehensive income (loss) $ 152,047 $ 143,936 $ 81,389 $ (225,325 ) $ 152,047 CONDENSED CONSOLIDATING STATEMENTS OF CASH FLOWS For the Year Ended September 30, 2020 Parent Company Guarantor Companies Non-Guarantor Companies Elimination Consolidation CASH FLOWS FROM OPERATING ACTIVITIES: Net income (loss) $ 53,429 $ 101,960 $ 102,002 $ (203,962 ) $ 53,429 Net cash provided by operating activities 23,114 55,353 58,562 — 137,029 CASH FLOWS FROM INVESTING ACTIVITIES: Acquisition of property, plant and equipment (348 ) (42,268 ) (6,382 ) — (48,998 ) Acquired business, net of cash acquired — — (10,531 ) — (10,531 ) Proceeds from sale of assets — 345 7 — 352 Investment purchases (130 ) — — — (130 ) Net cash used in investing activities (478 ) (41,923 ) (16,906 ) — (59,307 ) CASH FLOWS FROM FINANCING ACTIVITIES: Proceeds from issuance of common stock 178,165 — — — 178,165 Purchase of shares for treasury (7,479 ) — — — (7,479 ) Proceeds from long-term debt 1,234,723 — 5,357 — 1,240,080 Payments of long-term debt (1,272,688 ) (3,421 ) (32,806 ) — (1,308,915 ) Financing costs (17,384 ) — — — (17,384 ) Acquisition costs — — (1,733 ) — (1,733 ) Dividends paid (14,529 ) — — — (14,529 ) Other, net 260 580 (855 ) — (15 ) Net cash provided by (used in) financing activities 101,068 (2,841 ) (30,037 ) — 68,190 CASH FLOWS FROM DISCONTINUED OPERATIONS: Net cash used in discontinued operations — — (2,577 ) — (2,577 ) Effect of exchange rate changes on cash and equivalents — (121 ) 2,498 — 2,377 NET INCREASE (DECREASE) IN CASH AND EQUIVALENTS 123,704 10,468 11,540 — 145,712 CASH AND EQUIVALENTS AT BEGINNING OF PERIOD 1,649 25,217 45,511 — 72,377 CASH AND EQUIVALENTS AT END OF PERIOD $ 125,353 $ 35,685 $ 57,051 $ — $ 218,089 CONDENSED CONSOLIDATING STATEMENTS OF CASH FLOWS For the Year Ended September 30, 2019 Parent Company Guarantor Companies Non-Guarantor Companies Elimination Consolidation CASH FLOWS FROM OPERATING ACTIVITIES: Net income (loss) $ 37,287 $ 94,637 $ 81,089 $ (175,726 ) $ 37,287 Net (income) loss from discontinued operations — — 8,335 — 8,335 Net cash provided by (used in) operating activities 42,159 41,992 29,807 — 113,958 CASH FLOWS FROM INVESTING ACTIVITIES: Acquisition of property, plant and equipment (542 ) (38,872 ) (5,947 ) — (45,361 ) Acquired business, net of cash acquired (9,219 ) — — — (9,219 ) Proceeds from sale of business (9,500 ) — — — (9,500 ) Insurance payments (10,604 ) — — — (10,604 ) Proceeds from sale of assets — 254 26 — 280 Investment purchases (149 ) — — — (149 ) Net cash provided by (used in) investing activities (30,014 ) (38,618 ) (5,921 ) — (74,553 ) CASH FLOWS FROM FINANCING ACTIVITIES: Purchase of shares for treasury (1,478 ) — — — (1,478 ) Proceeds from long-term debt 163,297 — 38,451 — 201,748 Payments of long-term debt (173,345 ) (2,973 ) (41,930 ) — (218,248 ) Change in short-term borrowings — (366 ) — — (366 ) Financing costs (1,090 ) — — — (1,090 ) Contingent consideration for acquired businesses — — (1,686 ) — (1,686 ) Dividends paid (13,676 ) — — — (13,676 ) Other, net (180 ) 8,830 (8,830 ) — (180 ) Net cash provided by (used in) financing activities (26,472 ) 5,491 (13,995 ) — (34,976 ) CASH FLOWS FROM DISCONTINUED OPERATIONS: Net cash used in discontinued operations — — (2,123 ) — (2,123 ) Effect of exchange rate changes on cash and equivalents — (1 ) 314 — 313 NET INCREASE IN CASH AND EQUIVALENTS (14,327 ) 8,864 8,082 — 2,619 CASH AND EQUIVALENTS AT BEGINNING OF PERIOD 15,976 16,353 37,429 — 69,758 CASH AND EQUIVALENTS AT END OF PERIOD $ 1,649 $ 25,217 $ 45,511 $ — $ 72,377 CONDENSED CONSOLIDATING STATEMENTS OF CASH FLOWS For the Year Ended September 30, 2018 Parent Company Guarantor Companies Non-Guarantor Companies Elimination Consolidation CASH FLOWS FROM OPERATING ACTIVITIES: Net income (loss) $ 125,678 $ 122,687 $ 84,680 $ (207,367 ) $ 125,678 Net income (loss) from discontinued operations — (92,423 ) — — (92,423 ) Net cash provided by (used in) operating activities 381,417 (405,174 ) 108,981 (27,032 ) 58,192 CASH FLOWS FROM INVESTING ACTIVITIES: Acquisition of property, plant and equipment (544 ) (41,531 ) (8,063 ) — (50,138 ) Acquired business, net of cash acquired (368,936 ) (4,843 ) (57,153 ) — (430,932 ) Proceeds from sale of business — 474,727 — — 474,727 Insurance proceeds 8,254 — — — 8,254 Proceeds from sale of property, plant and equipment — 62 601 — 663 Net cash used in investing activities (361,226 ) 428,415 (64,615 ) — 2,574 CASH FLOWS FROM FINANCING ACTIVITIES: Purchase of shares for treasury (45,605 ) — — — (45,605 ) Proceeds from long-term debt 411,623 2,125 29,310 — 443,058 Payments of long-term debt (269,478 ) (5,403 ) (26,112 ) — (300,993 ) Change in short-term borrowings — 144 — — 144 Financing costs (7,793 ) — — — (7,793 ) Purchase of ESOP shares — — — — — Dividends paid (49,797 ) — — — (49,797 ) Other, net (46,405 ) 4,733 14,691 27,032 51 Net cash provided by (used in) financing activities (7,455 ) 1,599 17,889 27,032 39,065 CASH FLOWS FROM DISCONTINUED OPERATIONS: Net cash provided by (used in) discontinued operations — (16,394 ) (62,533 ) — (78,927 ) Effect of exchange rate changes on cash and equivalents — (159 ) 1,332 — 1,173 NET DECREASE IN CASH AND EQUIVALENTS 12,736 8,287 1,054 — 22,077 CASH AND EQUIVALENTS AT BEGINNING OF PERIOD 3,240 8,066 36,375 — 47,681 CASH AND EQUIVALENTS AT END OF PERIOD $ 15,976 $ 16,353 $ 37,429 $ — $ 69,758

SUBSEQUENT EVENTS

SUBSEQUENT EVENTS	12 Months Ended
	Sep. 30, 2020
Subsequent Events [Abstract]
SUBSEQUENT EVENTS	SUBSEQUENT EVENTS On November 12, 2020, the Board of Directors declared a cash dividend of $0.08 per share, payable on December 17, 2020 to shareholders of record as of the close of business on November 25, 2020. Griffon currently intends to pay dividends each quarter; however, payment of dividends is determined by the Board of Directors, at its discretion, based on various factors, and no assurance can be provided as to the payment of future dividends. *****

SCHEDULE II VALUATION AND QUALI

SCHEDULE II VALUATION AND QUALIFYING ACCOUNTS	12 Months Ended
	Sep. 30, 2020
SEC Schedule, 12-09, Valuation and Qualifying Accounts [Abstract]
SCHEDULE II VALUATION AND QUALIFYING ACCOUNTS	SCHEDULE II GRIFFON CORPORATION VALUATION AND QUALIFYING ACCOUNTS For the Years Ended September 30, 2020, 2019 and 2018 (in thousands) Description Balance at Beginning of Year Recorded to Cost and Expense Accounts Written Off, net Other (1) Balance at End of Year FOR THE YEAR ENDED SEPTEMBER 30, 2020 Allowance for Doubtful Accounts Bad debts $ 1,881 $ 2,231 (255 ) $ (1 ) $ 3,856 Sales returns and allowances 6,000 12,163 (4,261 ) — 13,902 $ 7,881 $ 14,394 $ (4,516 ) $ (1 ) $ 17,758 Inventory valuation $ 26,169 $ 10,542 $ (3,412 ) $ 325 $ 33,624 Deferred tax valuation allowance $ 10,823 $ (999 ) $ — $ — $ 9,824 FOR THE YEAR ENDED SEPTEMBER 30, 2019 Allowance for Doubtful Accounts Bad debts $ 1,824 $ 464 $ (425 ) $ 18 $ 1,881 Sales returns and allowances 4,584 5,790 (4,374 ) — 6,000 $ 6,408 $ 6,254 $ (4,799 ) $ 18 $ 7,881 Inventory valuation $ 26,065 $ 2,774 $ (2,614 ) $ (56 ) $ 26,169 Deferred tax valuation allowance $ 8,520 $ 2,303 $ — $ — $ 10,823 FOR THE YEAR ENDED SEPTEMBER 30, 2018 Allowance for Doubtful Accounts Bad debts $ 1,109 $ (40 ) $ 11 $ 744 $ 1,824 Sales returns and allowances 4,857 4,088 (4,760 ) 399 4,584 $ 5,966 $ 4,048 $ (4,749 ) $ 1,143 $ 6,408 Inventory valuation $ 16,419 $ 1,924 $ (306 ) $ 8,028 $ 26,065 Deferred tax valuation allowance $ 17,466 $ (8,946 ) $ — $ — $ 8,520 Note (1): For the year ended September 30, 2018, Other primarily consists of opening balances of reserves assumed from acquisitions.

DESCRIPTION OF BUSINESS AND S_2

DESCRIPTION OF BUSINESS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)	12 Months Ended
	Sep. 30, 2020
Accounting Policies [Abstract]
Consolidation	Consolidation The consolidated financial statements include the accounts of Griffon and all subsidiaries. Intercompany accounts and transactions have been eliminated in consolidation. The results of operations of acquired businesses are included from the dates of acquisitions.
Earnings per share	Earnings per share Due to rounding, the sum of earnings per share may not equal earnings per share of Net income.
Discontinued operations	As a result, Griffon classified the results of operations of the Plastics business as discontinued operations in the Consolidated Statements of Operations for all periods presented and classified the related assets and liabilities associated with the discontinued operations in the consolidated balance sheets. All results and information presented exclude Plastics unless otherwise noted. See Note 7, Discontinued Operations.
Reclassifications	Reclassifications Certain amounts in prior years have been reclassified to conform to the current year presentation.
Use of estimates	Use of estimates The preparation of financial statements in conformity with accounting principles generally accepted in the United States requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosure of contingent assets and liabilities at the date of the financial statements, and the reported amounts of revenue and expenses during the reporting periods. These estimates may be adjusted due to changes in economic, industry or customer financial conditions, as well as changes
Cash and equivalents	Cash and equivalents Griffon considers all highly liquid investments purchased with an initial maturity of three months or less to be cash equivalents. Cash equivalents primarily consist of overnight commercial paper, highly-rated liquid money market funds backed by U.S. Treasury securities and U.S. Agency securities, as well as insured bank deposits. Griffon had cash in non-U.S. bank accounts of approximately $55,000 and $34,200 at September 30, 2020 and 2019, respectively. Substantially all U.S. cash and equivalents are in excess of FDIC insured limits. Griffon regularly evaluates the financial stability of all institutions and funds that hold its cash and equivalents.
Fair value of financial instruments	Fair value of financial instruments The carrying values of cash and cash equivalents, accounts receivable, accounts and notes payable and revolving credit debt approximate fair value due to either the short-term nature of such instruments or the fact that the interest rate of the revolving credit debt is based upon current market rates. The fair value hierarchy, as outlined in the applicable accounting guidance, establishes a fair value hierarchy that requires the Company to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. A financial instrument’s categorization within the hierarchy is based on the lowest level of input that is significant to the fair value measurement. The accounting guidance establishes three levels of inputs that may be used to measure fair value, as follows: • Level 1 inputs are measured and recorded at fair value based upon quoted prices in active markets for identical assets. • Level 2 inputs include inputs other than Level 1 that are observable, either directly or indirectly, such as quoted prices in active markets for similar assets and liabilities, quoted prices for identical or similar assets or liabilities in markets that are not active, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of assets or liabilities. • Level 3 inputs are unobservable inputs in which little or no market data exists, therefore requiring an entity to develop its own assumptions. The fair value of Griffon’s 2028 Senior Notes approximated $1,040,000 , on September 30, 2020 . Fair values were based upon quoted market prices (level 1 inputs). Insurance contracts with a value of $3,436 at September 30, 2020 are measured and recorded at fair value based upon quoted prices in active markets for similar assets (level 2 inputs) and are included in Other current assets on the consolidated balance sheet. Items Measured at Fair Value on a Recurring Basis At September 30, 2020 and 2019, trading securities, measured at fair value based on quoted prices in active markets for similar assets (level 2 inputs), with a fair value of $1,703 ( $1,000 cost basis) and $1,518 ( $1,000 cost basis), respectively, were included in Prepaid and other current assets on the Consolidated Balance Sheets. In the normal course of business, Griffon’s operations are exposed to the effect of changes in foreign currency exchange rates. To manage these risks, Griffon may enter into various derivative contracts such as foreign currency exchange contracts, including forwards and options. During 2020 and 2019, Griffon entered into several such contracts in order to lock into a foreign currency rate for planned settlements of trade and inter-company liabilities payable in USD. At September 30, 2020 and 2019, Griffon had $32,000 and $14,000 of Australian dollar contracts at a weighted average rate of $1.41 and $1.48 , respectively, which qualified for hedge accounting. These hedges were all deemed effective as cash flow hedges with gains and losses related to changes in fair value deferred and recorded in Other comprehensive income (loss) and Prepaid and other current assets, or Accrued liabilities, until settlement. Upon settlement, gains and losses were recognized in the Consolidated Statements of Operations and Comprehensive Income (Loss) in Cost of goods and services. AOCI included deferred losses of $168 ( $109 , net of tax) and deferred gains of $327 ( $213 , net of tax) at September 30, 2020 and 2019, respectively. Upon settlement, gains (losses) of $(2,163) and $1,361 were recognized in the Consolidated Statements of Operations and Comprehensive Income (Loss) in Cost of goods and services ("COGS") during 2020 and 2019, respectively. Contracts expire in 30 to 146 days . At September 30, 2020 and 2019, Griffon had $7,900 and $3,500 , respectively, of Canadian dollar contracts at a weighted average rate of $1.33 and $1.32 . These contracts, which protect Canadian operations from currency fluctuations for U.S. dollar based purchases, do not qualify for hedge accounting and fair value gains (losses) of $(92) and $14 were recorded in Other assets and to Other income for the outstanding contracts, based on similar contract values (level 2 inputs), for the years ended September 30, 2020 and 2019, respectively. Realized gains of $189 and $68 , were recorded in Other income during 2020 and 2019, respectively. Contracts expire in 30 to 360 days . At September 30, 2020, Griffon had $5,400 of Great Britain Pound contracts at a weighted average rate of $0.77 . These contracts, which protect U.K. operations from currency fluctuations for U.S. dollar based purchases, do not qualify for hedge accounting and fair value gains of $39 were recorded in Other assets and to Other income for the outstanding contracts, based on similar contract values (level 2 inputs), for the years ended September 30, 2020. There were no realized gains or losses recorded for these contracts during the year ended September 30, 2020. Contracts expire in 2 to 208 days . Pension plan assets with a fair value of $147,145 at September 30, 2020 , are measured and recorded at fair value based upon quoted prices in active markets for identical assets (level 1 inputs), quoted market prices for similar assets (level 2 inputs) and fair value assumptions for unobservable inputs in which little or no market data exists (level 3).
Non-U.S. currency translation	Non-U.S. currency translation Assets and liabilities of non-U.S. subsidiaries, where the functional currency is not the U.S. dollar, have been translated at year-end exchange rates and profit and loss accounts have been translated using weighted average exchange rates. Adjustments resulting from currency translation have been recorded in the equity section of the balance sheet in AOCI as cumulative translation adjustments. Cumulative translation adjustments were gains (losses) of $5,601 and $(8,460) for 2020 and 2019, respectively. As of September 30, 2020 and 2019, the foreign currency translation components of Accumulated other comprehensive loss were $25,683 and $31,284 , respectively. Assets and liabilities of an entity that are denominated in currencies other than that entity’s functional currency are re-measured into the functional currency using period end exchange rates, or historical rates where applicable to certain balances. Gains and losses arising on remeasurements are recorded within the Consolidated Statement of Operations and Comprehensive Income as a component of Other income (expense).
Revenue recognition	Revenue recognition Effective October 1, 2018, the Company adopted Accounting Standard Codification (“ASC”) Topic 606, Revenue from Contracts with Customers. Our statement of operations for the year ended September 30, 2020 and 2019 and our balance sheet as of September 30, 2020 and 2019 are presented under ASC 606, while our statement of operations for the year ended September 30, 2018 is presented under ASC 605, Revenue Recognition. Under ASC Topic 606, performance obligation is a promise in a contract to transfer a distinct good or service, or a bundle of goods or services, to the customer, and is the unit of accounting under ASC Topic 606. A contract with a customer is an agreement which both parties have approved, that creates enforceable rights and obligations, has commercial substance and with respect to which payment terms are identified and collectability is probable. Once the Company has entered into a contract or purchase order, it is evaluated to identify performance obligations. For each performance obligation, revenue is recognized when control of the promised products is transferred to the customer, or services are satisfied under the contract or purchase order, in an amount that reflects the consideration the Company expects to be entitled to in exchange for those products or services (the transaction price). A contract's transaction price is allocated to each distinct performance obligation and recognized as revenue when each performance obligation is satisfied. A majority of the Company’s contracts have a single performance obligation which represents, in most cases, the product being sold to the customer. To a lesser extent, some contracts include multiple performance obligations such as a product, the related installation, and extended warranty services. These contracts require judgment in determining the number of performance obligations. For contracts with multiple performance obligations, judgment is required to determine whether performance obligations specified in these contacts are distinct and should be accounted for as separate revenue transactions for recognition purposes. In these types of contracts, the Company allocates the total transaction price to each performance obligation in an amount based on the estimated relative standalone selling prices of the promised goods or services underlying each performance obligation. The Company uses an observable price to determine the stand-alone selling price for separate performance obligations or a cost plus margin approach when one is not available. The transaction price includes variable consideration, such as discounts and volume rebates, when it is probable that a significant reversal of revenue recognized will not occur. Variable consideration is determined using either the expected value or the most likely amount of consideration to be received based on historical experience and the specific facts and circumstances at the time of evaluation. Approximately 86% of the Company’s performance obligations are recognized at a point in time related to the manufacture and sale of a broad range of products and components primarily within the CPP and HBP Segments, and revenue is recognized when title, and risk and rewards of ownership, have transferred to the customer, which is generally upon shipment. Approximately 14% of the Company’s performance obligations are recognized over time and relate to prime or subcontractors from contract awards with the U.S. Government, as well as foreign governments and other commercial customers within our DE Segment. Revenue recognized over time are generally accounted for using an input measure to determine progress completed at the end of the period. We believe that cumulative costs incurred to date as a percentage of estimated total contract costs at completion (cost-to-cost method) is an appropriate measure of progress towards satisfaction of performance obligations recognized over time, as it most accurately depicts the progress of our work and transfer of control to our customers.
Accounts receivable, allowance for doubtful accounts and concentrations of credit risk	Accounts receivable, allowance for doubtful accounts and concentrations of credit risk Accounts receivable is composed principally of trade accounts receivable, that arise from the sale of goods or services on account, and is stated at historical cost. A substantial portion of Griffon’s trade receivables are from customers within the CPP and HBP businesses, of which the largest customer is Home Depot, whose financial condition is dependent on the construction and related retail sectors of the economy. As a percentage of consolidated accounts receivable, U.S. Government related programs were 9% and Home Depot was 18% . Griffon performs continuing evaluations of the financial condition of its customers, and although Griffon generally does not require collateral, letters of credit may be required from customers in certain circumstances. Trade receivables are recorded at the stated amount, less allowance for doubtful accounts and, when appropriate, for customer program reserves and cash discounts. The allowance represents estimated uncollectible receivables associated with potential customer defaults on contractual obligations (usually due to customers’ potential insolvency). The allowance for doubtful accounts includes amounts for certain customers where a risk of default has been specifically identified, as well as an amount for customer defaults based on a formula when it is determined the risk of some default is probable and estimable, but cannot yet be associated with specific customers. The provision related to the allowance for doubtful accounts is recorded in Selling, general and administrative ("SG&A") expenses. The Company writes-off accounts receivable when they are deemed to be uncollectible.
Contract assets	Contract assets Contract assets consists of amounts accounted for under the cost-to-cost method
Inventories	Inventories Inventories, stated at the lower of cost (first-in, first-out or average) or market, include material, labor and manufacturing overhead costs. Griffon’s businesses typically do not require inventory that is susceptible to becoming obsolete or dated. In general, Telephonics sells products in connection with programs authorized and approved under contracts awarded by the U.S. Government or agencies thereof and in accordance with customer specifications. HBP produces residential and commercial sectional garage doors, commercial rolling steel door and grille products, and CPP produces long-handled tools and landscaping products, and storage and organizational products, both in response to orders from customers of retailers and dealers or based on expected orders, as applicable.
Property, plant and equipment	Property, plant and equipment Property, plant and equipment includes the historical cost of land, buildings, equipment and significant improvements to existing plant and equipment or, in the case of acquisitions, a fair market value appraisal of such assets completed at the time of acquisition. Expenditures for maintenance, repairs and minor renewals are expensed as incurred. When property or equipment is sold or otherwise disposed of, the related cost and accumulated depreciation is removed from the respective accounts and the gain or loss is recognized. No event or indicator of impairment occurred during the three years ended September 30, 2020 , which would require additional impairment testing of property, plant and equipment. Depreciation expense, which includes amortization of assets under capital leases, was $52,819 , $51,926 and $46,733 in 2020, 2019 and 2018, respectively, and was calculated on a straight-line basis over the estimated useful lives of the assets. Depreciation included in SG&A expenses was $19,656 , $19,026 and $16,306 in 2020, 2019 and 2018, respectively. The remaining components of depreciation, attributable to manufacturing operations, are included in Cost of goods and services. Estimated useful lives for property, plant and equipment are as follows: buildings and building improvements, 25 to 40 years ; machinery and equipment, 2 to 15 years ; and leasehold improvements, over the term of the lease or life of the improvement, whichever is shorter.
Goodwill and indefinite-lived intangibles	Goodwill and indefinite-lived intangibles Griffon has significant intangible and tangible long-lived assets on its balance sheet that includes goodwill and other intangible assets related to acquisitions. Goodwill represents the excess of the cost of net assets acquired in business combinations over the fair value of the identifiable tangible and intangible assets acquired and liabilities assumed in a business combination. We review goodwill and indefinite-lived intangibles for impairment at least annually in the fourth quarter, or more frequently whenever events or circumstances change that would more likely than not reduce the fair value of a reporting unit below the carrying amount. Such events or changes in circumstance include significant deterioration in overall economic conditions, changes in the business climate in which our reporting units operate, a decline in our market capitalization, operating performance indicators, when some portion of a reporting unit is disposed of or classified as held for sale, or when a change in the composition of reporting units occurs for other reasons, such as a change in operating segments. We had three reporting units at September 30, 2020 and 2019, which are our operating segments. We use both qualitative and quantitative approaches when testing goodwill and indefinite-lived intangibles for impairment. When determining the approach to use, we consider the current facts and circumstances of each reporting unit, as well as the excess of each reporting unit’s estimated fair value over its carrying value based on our most recent quantitative assessment. In addition, our qualitative approach evaluates industry and market conditions and various events impacting a reporting unit including, but not limited to, macroeconomic conditions, changes in the business environment in which our reporting units operate and other reporting unit specific events and circumstances. If, based on the qualitative assessment, we determine that it is more likely than not that the fair value of a reporting unit is greater than its carrying value, then a quantitative assessment is not necessary. However, if a quantitative assessment is necessary, we use the income approach methodology of valuation that includes the present value of expected future cash flows. We performed a quantitative annual impairment test as of September 30, 2019, and an interim quantitative impairment test as of March 31, 2020, to assess the impact of the global outbreak of COVID-19, using discounted future cash flows for each reporting unit, which did not result in impairments to goodwill. The more significant assumptions used for the interim impairment test as of March 31, 2020 were a five-year cash flow projection and a 3.0% terminal value to which discount rates between 7.1% and 9% were applied to calculate each unit’s fair value. To substantiate fair values derived from the income approach methodology of valuation, the implied fair value was compared to the marketplace fair value of a comparable industry grouping for reasonableness. Further, the fair values were reconciled to Griffon’s market capitalization. We performed a qualitative assessment as of September 30, 2020, as the estimated fair values of each reporting unit significantly exceeded the carrying value based on our most recent quantitative assessment, which was performed as of March 31, 2020. Our qualitative assessment determined that indicators that the fair value of each reporting unit was less than the carrying value were not present. With respect to indefinite-lived intangibles we performed a quantitative annual impairment test as of September 30, 2019, and an interim quantitative impairment test as of March 31, 2020, to assess the impact of the global outbreak of COVID-19, using a relief from royalty method, which did not result in impairments. We performed a qualitative assessment as of September 30, 2020 considering all the above factors and determined that indefinite-lived intangibles fair values were greater than their book values. Long-lived amortizable intangible assets, such as customer relationships and software, and tangible assets, primarily property, plant and equipment, are amortized over their expected useful lives, which involve significant assumptions and estimates. Long-lived intangible and tangible assets are tested for impairment by comparing estimated future undiscounted cash flows to the carrying value of the asset when an impairment indicator, such as change in business, customer loss or obsolete technology, exists. Fair value estimates are based on assumptions believed to be reasonable at the time, but such assumptions are subject to inherent uncertainty. Actual results may differ materially from those estimates. Any changes in key assumptions or management judgment with respect to a reporting unit or its prospects, which may result from a decline in Griffon’s stock price, a change in market conditions, market trends, interest rates or other factors outside of Griffon’s control, or significant underperformance relative to historical or projected future operating results, could result in a significantly different estimate of the fair value of Griffon’s reporting units, which could result in an impairment charge in the future.
Definite-lived long-lived assets	Definite-lived long-lived assets Amortizable intangible assets are carried at cost less accumulated amortization. For financial reporting purposes, definite-lived intangible assets are amortized on a straight-line basis over their useful lives, generally eight to twenty-five years . Long-lived assets and certain identifiable intangible assets to be held and used are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of such assets may not be recoverable. Determination of recoverability is based on an estimate of undiscounted future cash flows resulting from the use of the asset and its eventual disposition.
Income taxes	Income taxes We are subject to Federal, state and local income taxes in the U.S. and in various taxing jurisdictions outside the U.S. We recognize deferred tax assets and liabilities for the expected future tax consequences of events that have been included in the financial statements or tax returns in accordance with applicable accounting guidance for accounting for income taxes, using currently enacted tax rates in effect for the year in which the differences are expected to reverse. We record a valuation allowance when necessary to reduce deferred tax assets to the amount expected to be realized. Deferred tax assets are reduced by a valuation allowance if, based on the weight of available evidence, it is more likely than not that some portion or all of the deferred tax assets will not be realized. Both positive and negative evidence are considered in forming our judgment as to whether a valuation allowance is appropriate, and more weight is given to evidence that can be objectively verified. Valuation allowances are reassessed whenever there are changes in circumstances that may cause a change in judgment. The accounting for uncertainty in income taxes requires a more-likely-than-not threshold for financial statement recognition of tax positions taken or expected to be taken in a tax return. We record, as needed, a liability for the difference between the benefit recognized for financial statement purposes and the tax position taken or expected to be taken on our tax return. To the extent that our assessment of such tax positions changes, the change in estimate is recorded in the period in which the determination is made.
Research and development costs, shipping and handling costs and advertising costs	Research and development costs, shipping and handling costs and advertising costs Research and development costs not recoverable under contractual arrangements are charged to SG&A expense as incurred and amounted to approximately $15,400 in each year ended September 30, 2020, 2019 and 2018. SG&A expenses include shipping and handling costs of $54,500 in 2020 , $53,500 in 2019 and $41,700 in 2018 and advertising costs, which are expensed as incurred, of $19,000 in 2020 , $20,000 in 2019 and $21,000 in 2018.
Risk, retention and insurance	Risk, retention and insurance Griffon’s property and casualty insurance programs contain various deductibles that, based on Griffon’s experience, are reasonable and customary for a company of its size and risk profile. Griffon generally maintains deductibles for claims and liabilities related primarily to workers’ compensation, general, product and automobile liability as well as property damage and business interruption losses resulting from certain events. Griffon does not consider any of the deductibles to represent a material risk to Griffon. Griffon accrues for claim exposures that are probable of occurrence and can be reasonably estimated. Insurance is maintained to transfer risk beyond the level of self-retention and provides protection on both an individual claim and annual aggregate basis.
Pension benefits	Pension benefits Griffon sponsors defined and supplemental benefit pension plans for certain retired employees. Annual amounts relating to these plans are recorded based on actuarial projections, which include various actuarial assumptions, including discount rates, assumed rates of return, compensation increases and turnover rates. Actuarial assumptions used to determine pension liabilities, assets and expense are reviewed annually and modified based on current economic conditions and trends. The expected return on plan assets is determined based on the nature of the plan's investments and expectations for long-term rates of return. The discount rate used to measure obligations is based on a corporate bond spot-rate yield curve that matches projected future benefit payments, with the appropriate spot rate applicable to the timing of the projected future benefit payments. Assumptions used in determining Griffon’s obligations under the defined benefit pension plans are believed to be reasonable, based on experience and advice from independent actuaries; however, differences in actual experience or changes in assumptions may materially impact Griffon’s financial position or results of operations. All of the defined benefit plans are frozen and have ceased accruing benefits.
Issued but not yet effective accounting pronouncements and new accounting standards implemented	Issued but not yet effective accounting pronouncements In December 2019, the FASB issued guidance on simplifying the accounting for income taxes by clarifying and amending existing guidance related to the recognition of franchise tax, the evaluation of a step up in the tax basis of goodwill, and the effects of enacted changes in tax laws or rates in the effective tax rate computation, among other clarifications. Our effective date for adoption of this ASU is our fiscal year beginning October 1, 2021 with early adoption permitted. We are currently evaluating the effects that the adoption of this guidance will have on our consolidated financial statements and the related disclosures. In April 2019, the FASB issued guidance relating to accounting for credit losses on financial instruments, including trade receivables, and derivatives and hedging. This guidance is effective for all entities for fiscal years beginning after December 15, 2019, and interim periods within those fiscal years, with early adoption permitted, and will be effective for the Company beginning in fiscal 2021. Management does not expect a material impact to the Company’s Consolidated Statements of Operations and Comprehensive Income or Cash Flows. In August 2018, the FASB issued guidance which modifies the disclosures on fair value measurements by removing the requirement to disclose the amount and reasons for transfers between Level 1 and Level 2 of the fair value hierarchy and the policy for timing of such transfers. This guidance expands the disclosure requirements for Level 3 fair value measurements, primarily focused on changes in unrealized gains and losses included in other comprehensive income (loss). This guidance is effective for fiscal years beginning after December 15, 2019, with early adoption permitted, and will be effective for the Company beginning in 2021. We are currently evaluating the effects that the adoption of this guidance will have on our consolidated financial statements and the related disclosures. In August 2018, the FASB issued guidance to clarify disclosure requirements related to defined benefit pension and other post-retirement plans. The guidance is effective for fiscal years beginning after December 15, 2020, with early adoption permitted, and will be effective for the Company beginning in 2022. We are currently evaluating the effects that the adoption of this guidance will have on our consolidated financial statements and the related disclosures. New Accounting Standards Implemented In March 2020, the Financial Accounting Standards Board ("FASB") issued optional guidance for a limited time relating to accounting for the discontinuation of the LIBOR rate also known as reference rate reform. The amendments in this update provide optional practical expedients and exceptions for applying U.S. GAAP to contracts, hedging relationships and other transactions affected by reference rate reform if certain criteria are met. The amendments in this update are applicable to contract modifications that replace a reference LIBOR rate beginning on March 12, 2020 through December 31, 2022. The optional expedients primarily apply to the Griffon’s Credit Agreement and Non-U.S. Term Loans. The optional expedients allow the Company to account for modifications due to reference rate reform by prospectively adjusting the effective interest rate on these agreements. The Company expects to apply the optional practical expedients and exceptions to modifications of its agreements affected by reference rate reform. As of September 30, 2020, the Company has not modified its agreements subject to reference rate reform. In February 2018, the FASB issued guidance that allows companies to reclassify stranded tax effects resulting from the 2017 Tax Cuts and Jobs Act, from accumulated other comprehensive income to retained earnings. This guidance is effective for all entities for fiscal years beginning after December 15, 2018, and interim periods within those fiscal years, with early adoption permitted, and is effective for the Company in fiscal 2020. Upon adoption of this guidance as of October 1, 2019, based on our evaluation, we elected not to reclassify the income tax effects of the Tax Cuts and Jobs Act from accumulated other comprehensive income to retained earnings. The adoption of this standard did not have an impact on the Company's financial condition, results of operations, or cash flow. In February 2016, FASB issued guidance on lease accounting requiring lessees to recognize a right-of-use asset and a lease liability for long-term leases and to disclose additional quantitative and qualitative information about leasing arrangements. The Company adopted the requirements of the new standard as of October 1, 2019 and applied the modified retrospective approach, whereby the cumulative effect of adoption is recognized as of the date of adoption and comparative prior periods are not retrospectively adjusted. As a result, upon adoption, we have recognized right-of-use assets of $163,552 and lease liabilities of $163,676 associated with our operating leases. The standard had no material impact to retained earnings or on our Consolidated Statements of Income or Consolidated Statements of Cash Flows. In January 2017, the FASB issued guidance that simplifies how an entity is required to test goodwill for impairment by eliminating Step 2 from the goodwill impairment test. Step 2 measures a goodwill impairment loss by comparing the implied fair value of a reporting unit's goodwill with the carrying amount of that goodwill. This guidance is effective for annual periods beginning after December 15, 2019, including interim periods within those periods and will be effective for the Company beginning in 2021. Early adoption is permitted for interim or annual goodwill impairment tests performed on testing dates after January 1, 2017. We early adopted this guidance for our annual goodwill impairment testing for the year ended September 30, 2020. The adoption of this guidance did not have a material impact on the Company's financial condition, results of operations and related disclosures. The Company has implemented all new accounting pronouncements that are in effect and that may impact its financial statements, and does not believe that there are any other new accounting pronouncements that have been issued that might have a material impact on its financial position or results of operations.

ACQUISITIONS (Tables)

ACQUISITIONS (Tables)	12 Months Ended
	Sep. 30, 2020
Business Combinations [Abstract]
Schedule of Recognized Identified Assets Acquired and Liabilities Assumed	The calculation of the purchase price allocation is as follows: Accounts receivable (1) $ 32,234 Inventories (2) 28,411 Property, plant and equipment 47,464 Goodwill 70,159 Intangible assets 74,580 Other current and non-current assets 3,852 Total assets acquired 256,700 Accounts payable and accrued liabilities 68,251 Long-term liabilities 2,720 Total liabilities assumed 70,971 Total $ 185,729 (1) Includes $32,956 of gross accounts receivable of which $722 was not expected to be collected. The fair value of accounts receivable approximated book value acquired. (2) Includes $1,500 in inventory basis step-up, which was charged to cost of goods sold over the inventory turns of the acquired entity. The calculation of the purchase price allocation is as follows: Accounts receivable (1) $ 30,400 Inventories (2) 12,336 Property, plant and equipment 49,426 Goodwill 43,183 Intangible assets 67,600 Other current and non-current assets 2,648 Total assets acquired 205,593 Accounts payable and accrued liabilities 12,507 Long-term liabilities 660 Total liabilities assumed 13,167 Total $ 192,426 (1) Includes $30,818 of gross accounts receivable of which $418 was not expected to be collected. The fair value of accounts receivable approximated book value acquired. (2) Includes $13,434 of gross inventory of which $1,098 was reserved for obsolete items.
Schedule of Goodwill and Intangible Assets Acquired as Part of Business Combination	The amounts assigned to goodwill and major intangible asset classifications, all of which are tax deductible, for the ClosetMaid acquisition are as follows: Average Goodwill $ 70,159 N/A Indefinite-lived intangibles 47,740 N/A Definite-lived intangibles 26,840 21 Total goodwill and intangible assets $ 144,739 The amounts assigned to goodwill and major intangible asset classifications, all of which are tax deductible, for the CornellCookson acquisition are as follows: Average Goodwill $ 43,183 N/A Indefinite-lived intangibles 53,500 N/A Definite-lived intangibles 14,100 12 Total goodwill and intangible assets $ 110,783

INVENTORIES (Tables)

INVENTORIES (Tables)	12 Months Ended
	Sep. 30, 2020
Inventory Disclosure [Abstract]
Schedule of Inventory, Current	The following table details the components of inventory: At September 30, At September 30, Raw materials and supplies $ 135,083 $ 121,791 Work in process 81,624 93,830 Finished goods 197,118 226,500 Total $ 413,825 $ 442,121

PROPERTY, PLANT AND EQUIPMENT (

PROPERTY, PLANT AND EQUIPMENT (Tables)	12 Months Ended
	Sep. 30, 2020
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment	The following table details the components of property, plant and equipment, net: At September 30, At September 30, Land, building and building improvements $ 167,005 $ 133,036 Machinery and equipment 595,126 580,698 Leasehold improvements 53,386 49,808 815,517 763,542 Accumulated depreciation and amortization (471,553 ) (426,216 ) Total $ 343,964 $ 337,326

GOODWILL AND OTHER INTANGIBLES

GOODWILL AND OTHER INTANGIBLES (Tables)	12 Months Ended
	Sep. 30, 2020
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Goodwill	The following table provides changes in carrying value of goodwill by segment through the year ended September 30, 2020 : At September 30, Goodwill from acquisitions Reallocation of Goodwill (1) Foreign currency translation adjustments At September 30, Goodwill from acquisitions Foreign currency translation adjustments At September 30, Consumer and Professional Products $ 378,046 $ — $ (148,076 ) $ (2,701 ) $ 227,269 $ 4,451 $ 1,125 $ 232,845 Home and Building Products 42,804 300 148,076 73 191,253 — — 191,253 Defense Electronics 18,545 — — — 18,545 — — 18,545 Total $ 439,395 $ 300 $ — $ (2,628 ) $ 437,067 $ 4,451 $ 1,125 $ 442,643 (1) In accordance with the guidance set forth in ASC 350, and in connection with the modification of the Company's reportable segment structure, using a relative fair value approach, the Company reallocated $148,076
Schedule of Identifiable Intangible Assets	The following table provides the gross carrying value and accumulated amortization for each major class of intangible asset: At September 30, 2020 At September 30, 2019 Gross Carrying Amount Accumulated Amortization Average Life (Years) Gross Carrying Amount Accumulated Amortization Customer relationships & other $ 185,940 $ 66,656 23 $ 183,515 $ 57,783 Unpatented technology 19,464 8,360 13 19,167 7,329 Total amortizable intangible assets 205,404 75,016 202,682 65,112 Trademarks 224,640 — 219,069 — Total intangible assets $ 430,044 $ 75,016 $ 421,751 $ 65,112

DISCONTINUED OPERATIONS (Tables

DISCONTINUED OPERATIONS (Tables)	12 Months Ended
	Sep. 30, 2020
Discontinued Operations and Disposal Groups [Abstract]
Schedule of Disposal Groups, Including Discontinued Operations, Income Statement, Balance Sheet and Additional Disclosures	The following amounts related to the Plastics segment have been segregated from Griffon's continuing operations and are reported as discontinued operations: For the Year Ended September 30, 2019 2018 Revenue $ — $ 166,262 Cost of goods and services — 132,100 Gross profit — 34,162 Selling, general and administrative expenses 9,500 26,303 Restructuring charges — — Total operating expenses 9,500 26,303 Income from discontinued operations (9,500 ) 7,859 Other income (expense) Gain on sale of business — 112,964 Interest expense, net — (155 ) Other, net — (687 ) Total other income (expense) — 112,122 Income from operations of discontinued operations (9,500 ) 119,981 The following amounts summarize the total assets and liabilities of Plastics and Installation Services and other discontinued activities which have been segregated from Griffon’s continuing operations and are reported as assets and liabilities of discontinued operations in the consolidated balance sheets: At September 30, At September 30, Assets of discontinued operations: Prepaid and other current assets $ 2,091 $ 321 Other long-term assets 6,406 2,888 Total assets of discontinued operations $ 8,497 $ 3,209 Liabilities of discontinued operations: Accrued liabilities, current $ 3,797 $ 4,333 Other long-term liabilities 7,014 3,331 Total liabilities of discontinued operations $ 10,811 $ 7,664

ACCRUED LIABILITIES (Tables)

ACCRUED LIABILITIES (Tables)	12 Months Ended
	Sep. 30, 2020
Payables and Accruals [Abstract]
Schedule of Accrued Liabilities	The following table details the components of accrued liabilities: At September 30, At September 30, Compensation $ 83,308 $ 61,639 Interest 4,371 4,501 Warranties and rebates 18,687 13,171 Insurance 10,997 11,996 Rent, utilities and freight 8,816 5,326 Income and other taxes 14,707 7,814 Marketing and advertising 7,968 4,417 Restructuring 2,965 — Other 19,753 15,801 Total $ 171,572 $ 124,665

RESTRUCTURING CHARGES (Tables)

RESTRUCTURING CHARGES (Tables)	12 Months Ended
	Sep. 30, 2020
Restructuring and Related Activities [Abstract]
Restructuring and Related Cost	A summary of the restructuring and other related charges included in Cost of goods and services and Selling, general and administrative expenses in the Company's Consolidated Statements of Operations were as follows: For the Year Ended September 30, 2020 Cost of goods and services $ 4,159 Selling, general and administrative expenses 11,630 Total restructuring charges $ 15,789 For the Year Ended September 30, 2020 Personnel related costs $ 7,740 Facilities, exit costs and other 3,357 Non-cash facility and other 4,692 Total $ 15,789
Schedule of Restructuring Reserve by Type of Cost	The following table summarizes the accrued liabilities of the Company's restructuring actions: Cash Charges Cash Charges Non Cash Charges Personnel related costs Facilities & Facility and Other Costs Total Accrued liability at September 30, 2019 $ — $ — $ — $ — Charges 7,740 3,357 4,692 15,789 Payments (5,039 ) (3,093 ) — (8,132 ) Non-cash charges (1) — $ — (4,692 ) (4,692 ) Accrued liability at September 30, 2020 $ 2,701 $ 264 $ — $ 2,965 (1) Non-cash charges in Facility and Other Costs primarily represent the non-cash write-off of certain long-lived assets in connection with certain facility closures.

WARRANTY LIABILITY (Tables)

WARRANTY LIABILITY (Tables)	12 Months Ended
	Sep. 30, 2020
Product Warranties Disclosures [Abstract]
Schedule of Product Warranty Liability	Changes in Griffon’s warranty liability, included in Accrued liabilities, were as follows: Years Ended September 30, 2020 2019 Balance, beginning of period $ 7,894 $ 8,174 Warranties issued and changes in estimated pre-existing warranties 20,474 16,938 Actual warranty costs incurred (17,525 ) (17,218 ) Balance, end of period $ 10,843 $ 7,894

LONG-TERM DEBT (Tables)

LONG-TERM DEBT (Tables)	12 Months Ended
	Sep. 30, 2020
Debt Disclosure [Abstract]
Schedule of Long-term Debt	Debt at September 30, 2020 and 2019 consisted of the following: At September 30, 2020 Outstanding Balance Original Issuer Premium Capitalized Fees & Expenses Balance Sheet Coupon Interest Rate Senior notes due 2028 (a) $ 1,000,000 $ 363 $ (15,376 ) $ 984,987 5.75 % Revolver due 2025 (b) 12,858 — (2,209 ) 10,649 Variable Finance lease - real estate (e) 17,218 — (30 ) 17,188 Variable Non U.S. lines of credit (f) — — (30 ) (30 ) Variable Non U.S. term loans (f) 31,086 — (160 ) 30,926 Variable Other long term debt (g) 3,260 — (16 ) 3,244 Variable Totals 1,064,422 363 (17,821 ) 1,046,964 less: Current portion (9,922 ) — — (9,922 ) Long-term debt $ 1,054,500 $ 363 $ (17,821 ) $ 1,037,042 At September 30, 2019 Outstanding Balance Original Issuer Premium Capitalized Balance Sheet Coupon Interest Rate Senior notes due 2022 (a) $ 1,000,000 $ 867 $ (9,175 ) $ 991,692 5.25 % Revolver due 2021 (b) 50,000 — (1,243 ) 48,757 Variable Finance lease - real estate (e) 4,388 — (55 ) 4,333 5.00 % Non U.S. lines of credit (f) 17,576 — (45 ) 17,531 Variable Non U.S. term loans (f) 36,977 — (188 ) 36,789 Variable Other long term debt (g) 5,190 — (18 ) 5,172 Variable Totals 1,114,131 867 (10,724 ) 1,104,274 less: Current portion (10,525 ) — — (10,525 ) Long-term debt $ 1,103,606 $ 867 $ (10,724 ) $ 1,093,749 Interest expense consists of the following for 2020, 2019 and 2018. Year Ended September 30, 2020 Effective Interest Rate Cash Interest Amort. Debt Premium Amort. Deferred Cost & Other Fees Total Interest Expense Senior notes due 2028 (a) 5.90 % $ 32,511 $ — $ 1,072 $ 33,583 Senior notes due 2022 (a) 5.67 % $ 22,816 $ 122 $ 1,735 $ 24,673 Revolver due 2025 (b) Variable 5,866 — 635 6,501 Finance lease - real estate (e) Variable 386 — 25 411 Non U.S. lines of credit (f) Variable 12 — 15 27 Non U.S. term loans (f) Variable 975 — 55 1,030 Other long term debt (g) Variable 445 — 2 447 Capitalized interest (128 ) — — (128 ) Totals $ 62,883 $ 122 $ 3,539 $ 66,544 Year Ended September 30, 2019 Effective Interest Rate Cash Interest Amort. Debt Premium Amort. Deferred Cost & Other Fees Total Interest Expense Senior notes due 2022 (a) 5.66 % $ 52,500 $ 270 $ 3,803 $ 56,573 Revolver due 2025 (b) Variable 6,998 — 980 7,978 ESOP Loans (d) 6.3 % 937 — 186 1,123 Finance lease - real estate (e) Variable 372 — 25 397 Non U.S. lines of credit (f) Variable 19 — 15 34 Non U.S. term loan (f) Variable 1,592 — 109 1,701 Other long term debt (g) Variable 640 — 5 645 Capitalized interest (385 ) — — (385 ) Totals $ 62,673 $ 270 $ 5,123 $ 68,066 Year Ended September 30, 2018 Effective Interest Rate Cash Interest Amort. Debt Amort. Deferred Cost & Other Fees Total Interest Expense Senior notes due 2022 (a) 5.66 % $ 52,500 $ 270 $ 3,803 $ 56,573 Revolver due 2025 (b) Variable 3,718 — 565 4,283 Real estate mortgages (c) 6.3 % 1,802 — 124 1,926 ESOP Loans (d) 3.3 % 349 — 320 669 Finance lease - real estate (e) Variable 581 — 25 606 Non U.S. lines of credit (f) Variable 34 — 15 49 Non U.S. term loan (f) Variable 1,420 — 90 1,510 Other long term debt (g) Variable 494 — 7 501 Capitalized interest (549 ) — — (549 ) Totals $ 60,349 $ 270 $ 4,949 $ 65,568 Minimum payments under debt agreements for the next five years are as follows: $9,922 in 2021 , $12,667 in 2022 , $16,124 in 2023 , $1,730 in 2024 , $14,628 in 2025 and $1,009,351 thereafter. (a) On June 22, 2020, in an unregistered offering through a private placement, Griffon completed the add-on offering of $150,000 principal amount of its 5.75% senior notes due 2028, at 100.25% of par, to Griffon's previously issued $850,000 principal amount of its 5.75% senior notes due 2028, at of par, completed on February 19, 2020 (collectively, the "Senior Notes"). Proceeds from the Senior Notes were used to redeem the $1,000,000 of 5.25% senior notes due 2022 (the "2022 Senior Notes"). As of September 30, 2020, outstanding Senior Notes due totaled $1,000,000 ; interest is payable semi-annually on March 1 and September 1. The Senior Notes are senior unsecured obligations of Griffon guaranteed by certain domestic subsidiaries, and subject to certain covenants, limitations and restrictions. On April 22, 2020 and August 3, 2020, Griffon exchanged substantially all of the Senior Notes for substantially identical Senior Notes registered under the Securities Act of 1933, as amended (the "Securities Act"), via an exchange offer. The fair value of the 2028 Senior Notes approximated $1,040,000 on September 30, 2020 based upon quoted market prices (level 1 inputs). In connection with these transactions, Griffon capitalized $16,448 of underwriting fees and other expenses incurred related to the issuance and exchange of the Senior Notes, which will amortize over the term of such notes, and, at September 30, 2020, $15,376 remained to be amortized. Furthermore, all of the obligations associated with the 2022 Senior Notes were discharged. Additionally, Griffon recognized a $7,925 loss on the early extinguishment of debt of the 5.25% $1,000,000 2022 Senior Notes, comprised primarily of the write-off of $6,725 of remaining deferred financing fees, $607 of tender offer net premium expense and $593 of redemption interest expense. (b) On January 30, 2020, Griffon amended its Credit Agreement to increase the maximum borrowing availability from $350,000 to $400,000 , extend its maturity from March 22, 2021 to March 22, 2025 and modify certain other provisions of the facility. The facility includes a letter of credit sub-facility with a limit of $100,000 (increased from $50,000 ); and a multi-currency sub-facility of $100,000 . The Credit Agreement provides for same day borrowings of base rate loans. Borrowings under the Credit Agreement may be repaid and re-borrowed at any time. Interest is payable on borrowings at either a LIBOR or base rate benchmark rate, plus an applicable margin, which adjusts based on financial performance. Current margins are 0.75% for base rate loans and 1.75% for LIBOR loans. The Credit Agreement has certain financial maintenance tests including a maximum total leverage ratio, a maximum senior secured leverage ratio and a minimum interest coverage ratio, as well as customary affirmative and negative covenants and events of default. The negative covenants place limits on Griffon's ability to, among other things, incur indebtedness, incur liens, and make restricted payments and investments. Borrowings under the Credit Agreement are guaranteed by Griffon’s material domestic subsidiaries and are secured, on a first priority basis, by substantially all domestic assets of the Company and the guarantors, and a pledge of not greater than 65% of the equity interest in Griffon’s material, first-tier foreign subsidiaries. At September 30, 2020 , under the Credit Agreement, there were $12,858 in outstanding borrowings; outstanding standby letters of credit were $16,867 ; and $370,275 was available, subject to certain loan covenants, for borrowing at that date. (c) In September 2015 and March 2016, Griffon entered into mortgage loans in the amount of $32,280 and $8,000 , respectively, that were due to mature in September 2025 and April 2018, respectively. The mortgage loans were secured and collateralized by four properties occupied by Griffon's subsidiaries and were guaranteed by Griffon. The loans had an interest at a rate of LIBOR plus 1.50% . The loans were paid off during 2018. (d) In August 2016 and as amended on June 30, 2017, Griffon’s ESOP entered into a Term Loan with a bank (the "ESOP Agreement"). The Term Loan interest rate was LIBOR plus 3.00% . The Term Loan required quarterly principal payments of $569 with a balloon payment due at maturity. The Term Loan was secured by shares purchased with the proceeds of the loan and with a lien on a specific amount of Griffon assets (which ranked pari passu with the lien granted on such assets under the Credit Agreement) and was guaranteed by Griffon. On March 13, 2019, the ESOP Term Loan was refinanced with an internal loan from Griffon which was funded with cash and a draw under its Credit Agreement. The internal loan interest rate is fixed at 2.91% , matures in June 2033 and requires quarterly payments of principal, currently $635 , and interest. The internal loan is secured by shares purchased with the proceeds of the loan. The amount outstanding on the internal loan at September 30, 2020 was $29,878 . (e) Two Griffon subsidiaries have finance leases outstanding for real estate located in Troy, Ohio and Ocala, Florida. The leases mature in 2021 and 2025, respectively, and bear interest at fixed rates of approximately 5.0% and 5.6% , respectively. The Troy, Ohio lease is secured by a mortgage on the real estate and is guaranteed by Griffon. The Ocala, Florida lease contains two five-year renewal options. As of September 30, 2020, $17,188 was outstanding, net of issuance costs. Refer to Note 22 - Leases for further details. (f) In November 2012, Garant G.P. (“Garant”), a Griffon subsidiary, entered into a CAD 15,000 ( $11,210 as of September 30, 2020) revolving credit facility. The facility accrues interest at LIBOR (USD) or the Bankers Acceptance Rate (CDN) plus 1.3% per annum ( 1.44% LIBOR USD and 1.55% Bankers Acceptance Rate CDN as of September 30, 2020 ). The revolving facility matures in October 2022. Garant is required to maintain a certain minimum equity. As of September 30, 2020 , there were no borrowings under the revolving credit facility with CAD 15,000 ( $11,210 as of September 30, 2020 ) available for borrowing. In July 2016, Griffon Australia Holdings Pty Ltd and its Australian subsidiaries ("Griffon Australia") entered into an AUD 29,625 term loan, AUD 20,000 revolver and AUD 10,000 receivable purchase facility agreement; the agreement was amended in March 2019. As amended, the term loan requires quarterly principal payments of AUD 1,250 plus interest with a balloon payment of AUD 9,625 due upon maturity in March 2022, and accrues interest at Bank Bill Swap Bid Rate “BBSY” plus 1.95% per annum ( 2.09% at September 30, 2020 ). During the year ended September 30, 2020, the term loan balance was reduced by AUD 5,000 from AUD 23,375 to AUD 18,375 with proceeds from an AUD 5,000 increase in the commitment of the receivables purchase line from AUD 10,000 to AUD 15,000 . As of September 30, 2020 , the term loan had an outstanding balance of AUD 15,875 ( $11,287 as of September 30, 2020). The revolving facility and receivable purchase facility mature in March 2022, but are renewable upon mutual agreement with the lender. The revolving facility and receivable purchase facility accrue interest at BBSY plus 1.9% and 1.35% , respectively, per annum ( 2.04% and 1.49% , respectively, at September 30, 2020). At September 30, 2020, there were no balances outstanding under the revolver and the receivable purchase facility. The revolver, receivable purchase facility and term loan are all secured by substantially all of the assets of Griffon Australia and its subsidiaries. Griffon Australia is required to maintain a certain minimum equity level and is subject to a maximum leverage ratio and a minimum fixed charges cover ratio. In July 2018, the AMES Companies UK Ltd and its subsidiaries (collectively, "Ames UK") entered into a GBP 14,000 term loan, GBP 4,000 mortgage loan and GBP 5,000 revolver. The term loan and mortgage loan require quarterly principal payments of GBP 438 and GBP 105 plus interest, respectively, and have balloon payments due upon maturity, July 2023, of GBP 7,088 and GBP 2,349 , respectively. The term loan and mortgage loan accrue interest at the GBP LIBOR Rate plus 2.25% and 1.8% , respectively ( 2.30% and 1.85% at September 30, 2020, respectively). The revolving facility matures in May 2021, but is renewable upon mutual agreement with the lender, and accrues interest at the Bank of England Base Rate plus 1.5% ( 1.85% as of September 30, 2020). As of September 30, 2020, the revolver had no outstanding balance while the term and mortgage loan balances amounted to GBP 15,398 ( $19,799 as of September 30, 2020). The revolver and the term loan are both secured by substantially all of the assets of AMES UK and its subsidiaries. AMES UK is subject to a maximum leverage ratio and a minimum fixed charges cover ratio. An invoice discounting arrangement was canceled and replaced by the above loan facilities. (g) Other long-term debt primarily consists of a loan with the Pennsylvania Industrial Development Authority, with the balance consisting of capital leases.

EMPLOYEE BENEFIT PLANS (Tables)

EMPLOYEE BENEFIT PLANS (Tables)	12 Months Ended
	Sep. 30, 2020
Retirement Benefits [Abstract]
Schedule of Net Benefit Costs	Net periodic costs (benefits) were as follows: Defined Benefits for the Years Ended September 30, Supplemental Benefits for the Years Ended September 30, 2020 2019 2018 2020 2019 2018 Net periodic (benefits) costs: Interest cost $ 4,267 $ 5,778 $ 5,084 $ 335 $ 503 $ 544 Expected return on plan assets (10,343 ) (10,331 ) (10,736 ) — — — Amortization of: Prior service costs — — — 14 14 14 Actuarial loss 3,769 630 755 399 258 628 Total net periodic (benefits) costs $ (2,307 ) $ (3,923 ) $ (4,897 ) $ 748 $ 775 $ 1,186
Schedule of Assumptions Used	The weighted-average assumptions used in determining the net periodic (benefits) costs were as follows: Defined Benefits for the Years Ended September 30, Supplemental Benefits for the Years Ended September 30, 2020 2019 2018 2020 2019 2018 Discount rate 2.92 % 4.10 % 3.64 % 2.64 % 3.99 % 3.18 % Expected return on assets 7.00 % 7.00 % 7.25 % — % — % — %
Schedule of Plan Assets and Benefit Obligation of Defined Benefit Plan	Plan assets and benefit obligation of the defined and supplemental benefit plans were as follows: Defined Benefits at September 30, Supplemental Benefits at September 30, 2020 2019 2020 2019 Change in benefit obligation: Benefit obligation at beginning of fiscal year $ 177,797 $ 161,328 $ 16,180 $ 15,718 Interest cost 4,267 5,778 335 503 Benefits paid (10,747 ) (10,790 ) (1,939 ) (1,942 ) Actuarial (gain) loss 11,686 21,481 1,494 1,901 Benefit obligation at end of fiscal year 183,003 177,797 16,070 16,180 Change in plan assets: Fair value of plan assets at beginning of fiscal year 145,610 150,680 — — Actual return on plan assets 4,261 2,606 — — Company contributions 8,021 3,114 1,939 1,942 Benefits paid (10,747 ) (10,790 ) (1,939 ) (1,942 ) Fair value of plan assets at end of fiscal year 147,145 145,610 — — Projected benefit obligation in excess of plan assets $ (35,858 ) $ (32,187 ) $ (16,070 ) $ (16,180 ) Amounts recognized in the statement of financial position consist of: Accrued liabilities $ — $ — $ (1,891 ) $ (1,906 ) Other liabilities (long-term) (35,858 ) (32,187 ) (14,179 ) (14,279 ) Total Liabilities (35,858 ) (32,187 ) (16,070 ) (16,185 ) Net actuarial losses 61,666 47,663 7,700 6,609 Prior service cost — — — 14 Deferred taxes (12,950 ) (17,098 ) (1,617 ) (2,374 ) Total Accumulated other comprehensive loss, net of tax 48,716 30,565 6,083 4,249 Net amount recognized at September 30, $ 12,858 $ (1,622 ) $ (9,987 ) $ (11,936 ) Accumulated benefit obligations $ 183,003 $ 177,797 $ 16,070 $ 16,180 Information for plans with accumulated benefit obligations in excess of plan assets: ABO $ 183,003 $ 177,797 $ 16,070 $ 16,180 PBO 183,003 177,797 16,070 16,180 Fair value of plan assets 147,145 145,610 — —
Schedule of Weighted Average Assumptions Used in Defined and Supplemental Benefit Obligations	The weighted-average assumptions used in determining the benefit obligations were as follows: Defined Benefits at September 30, Supplemental Benefits at September 30, 2020 2019 2020 2019 Weighted average discount rate 2.30 % 2.92 % 1.69 % 2.64 %
Schedule of Expected Benefit Payments	Estimated future benefit payments to retirees, which reflect expected future service, are as follows: For the years ending September 30, Defined Benefits Supplemental Benefits 2021 $ 11,006 $ 1,891 2022 10,964 1,787 2023 10,945 1,679 2024 10,892 1,556 2025 10,809 1,437 2026 through 2030 52,390 5,354
Schedule of Actual and Weighted Average Assets Allocation for Qualified Benefit Plans	The actual and weighted-average asset allocation for qualified benefit plans were as follows: At September 30, 2020 2019 Target Cash and equivalents 0.4 % 1.9 % — % Equity securities 48.5 % 49.9 % 63.0 % Fixed income 31.9 % 29.4 % 37.0 % Other 19.2 % 18.8 % — % Total 100.0 % 100.0 % 100.0 %
Schedule of Fair Value of Pension and Postretirement Plan Assets by Asset Category	The following table presents the fair values of Griffon’s pension and post-retirement plan assets by asset category: At September 30, 2020 Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Total Cash and equivalents $ 600 $ — $ — $ 600 Government agency securities 33,675 6,136 — 39,811 Debt instruments 179 2,722 — 2,901 Equity securities 68,987 — — 68,987 Commingled funds — — 9,362 9,362 Limited partnerships and hedge fund investments — 17,867 — 17,867 Other Securities 2,488 163 — 2,651 Subtotal $ 105,929 $ 26,888 $ 9,362 $ 142,179 Accrued income and plan receivables 4,966 Total $ 147,145 At September 30, 2019 Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Total Cash and equivalents $ 2,791 $ — $ — $ 2,791 Government and agency securities 28,297 9,119 — 37,416 Debt instruments 182 2,996 — 3,178 Equity securities 72,517 — — 72,517 Commingled funds — — 8,776 8,776 Limited partnerships and hedge fund investments — 18,569 — 18,569 Other Securities 1,913 159 — 2,072 Subtotal $ 105,700 $ 30,843 $ 8,776 $ 145,319 Accrued income and plan receivables 291 Total $ 145,610 The following table represents level 3 significant unobservable inputs for the years ended September 30, 2020 and 2019: Significant As of October 1, 2019 $ — Purchases, issuances and settlements 7,695 Gains and losses 1,081 As of September 30, 2019 8,776 Purchases, issuances and settlements — Gains and losses 586 As of September 30, 2020 $ 9,362
Employee Stock Ownership Plan (ESOP) Disclosures	The ESOP shares were as follows: At September 30, 2020 2019 Allocated shares 3,301,448 3,209,069 Unallocated shares 2,058,187 2,259,308 Total 5,359,635 5,468,377

INCOME TAXES (Tables)

INCOME TAXES (Tables)	12 Months Ended
	Sep. 30, 2020
Income Tax Disclosure [Abstract]
Schedule of Income Loss From Continuing Operations Before Taxes	Income taxes have been based on the following components of Income before taxes from continuing operations: For the Years Ended September 30, 2020 2019 2018 Domestic $ 42,634 $ 49,723 $ 4,942 Non-U.S. 40,123 22,455 28,868 $ 82,757 $ 72,178 $ 33,810
Schedule of Components of Income Tax Expense (Benefit)	Provision (benefit) for income taxes on income was comprised of the following from continuing operations: For the Years Ended September 30, 2020 2019 2018 Current $ 27,233 $ 28,778 $ 18,188 Deferred 2,095 (2,222 ) (17,633 ) Total $ 29,328 $ 26,556 $ 555 U.S. Federal $ 10,978 $ 14,160 $ (12,714 ) State and local 7,331 6,187 5,175 Non-U.S. 11,019 6,209 8,094 Total provision $ 29,328 $ 26,556 $ 555
Schedule of Effective Income Tax Rate Reconciliation	Differences between the effective income tax rate applied to Income and the U.S. Federal income statutory rate from continuing operations were as follows: For the Years Ended September 30, 2020 2019 2018 U.S. Federal income tax provision (benefit) rate 21.0 % 21.0 % 24.5 % State and local taxes, net of Federal benefit 6.0 % 6.6 % 10.2 % Non-U.S. taxes - foreign permanent items and taxes 3.3 % 2.0 % 3.6 % Change in tax contingency reserves 0.1 % (0.7 )% (0.6 )% Impact of federal rate change on deferred tax balances — % — % (60.0 )% Tax Reform-Repatriation of Foreign Earnings and GILTI — % 1.0 % 61.6 % Change in valuation allowance (1.5 )% 3.3 % 13.4 % Other non-deductible/non-taxable items, net 1.4 % 3.1 % (5.2 )% Non-deductible officer's compensation 4.4 % 5.2 % 6.4 % Research and U.S. foreign tax credits 1.4 % (4.7 )% (39.4 )% Share based compensation — % 0.4 % (3.8 )% Other (0.7 )% (0.4 )% (9.1 )% Effective tax provision (benefit) rate 35.4 % 36.8 % 1.6 %
Schedule of Deferred Tax Assets and Liabilities	The tax effect of temporary differences that give rise to future deferred tax assets and liabilities are as follows: At September 30, 2020 2019 Deferred tax assets: Bad debt reserves $ 3,980 $ 1,980 Inventory reserves 9,371 8,361 Deferred compensation (equity compensation and defined benefit plans) 18,904 16,544 Compensation benefits 5,499 5,186 Insurance reserve 1,918 1,873 Warranty reserve 3,981 2,896 Lease liabilities 43,045 — Net operating loss 9,618 11,077 Tax credits 7,031 9,373 Capital loss carryback 2,205 2,000 Interest — 5,250 Other reserves and accruals 6,094 3,738 111,646 68,278 Valuation allowance (9,824 ) (10,823 ) Total deferred tax assets 101,822 57,455 Deferred tax liabilities: Goodwill and intangibles (44,051 ) (42,477 ) Property, plant and equipment (48,172 ) (43,996 ) Right-of-use assets (41,747 ) — Other (634 ) (1,096 ) Total deferred tax liabilities (134,604 ) (87,569 ) Net deferred tax liabilities $ (32,782 ) $ (30,114 )
Schedule of Components of Net Deferred Tax Asset Liability by Balance Sheet Account	The components of the net deferred tax liability, by balance sheet account, were as follows: At September 30, 2020 2019 Other assets $ 614 $ 137 Other liabilities (34,008 ) (31,141 ) Liabilities of discontinued operations 612 890 Net deferred liability $ (32,782 ) $ (30,114 )
Schedule of Unrecognized Tax Benefits Roll Forward	The following is a roll forward of unrecognized tax benefits: Balance at September 30, 2018 $ 4,519 Additions based on tax positions related to the current year 117 Additions based on tax positions related to prior years (559 ) Lapse of Statutes (16 ) Balance at September 30, 2019 4,061 Additions based on tax positions related to the current year 125 Additions based on tax positions related to prior years 20 Reductions based on tax positions related to prior years (3 ) Lapse of Statutes (23 ) Balance at September 30, 2020 $ 4,180

STOCKHOLDERS' EQUITY AND EQUI_2

STOCKHOLDERS' EQUITY AND EQUITY COMPENSATION (Tables)	12 Months Ended
	Sep. 30, 2020
Stockholders' Equity Note [Abstract]
Schedule of Compensation Cost for Share-based Payment Arrangements, Allocation of Share-based Compensation Costs by Plan	The following table summarizes the Company’s compensation expense relating to all stock-based compensation plans: For the Years Ended September 30, 2020 2019 2018 Restricted stock $ 14,702 $ 13,285 $ 10,078 ESOP 2,878 2,629 9,532 Total stock based compensation $ 17,580 $ 15,914 $ 19,610
Schedule of Share-based Compensation, Restricted Stock and Restricted Stock Units Activity	A summary of restricted stock activity, inclusive of restricted stock units, for 2020 is as follows: Shares Weighted Average Grant- Date Fair Value Unvested at September 30, 2019 3,713,573 $ 12.96 Granted 1,061,624 17.10 Vested (831,748 ) 21.51 Forfeited (257,859 ) 15.35 Unvested at September 30, 2020 3,685,590 14.30

COMMITMENTS AND CONTINGENT LI_2

COMMITMENTS AND CONTINGENT LIABILITIES COMMITMENTS AND CONTINGENT LIABILITIES (Tables)	12 Months Ended
	Sep. 30, 2020
Commitments and Contingencies Disclosure [Abstract]
Aggregate Future Maturities of Lease Payments for Operating Leases	Aggregate future maturities of lease payments for operating leases and finance leases as of September 30, 2020 are as follows (in thousands): Operating Leases Finance Leases 2021 $ 38,411 $ 4,282 2022 33,286 2,695 2023 25,599 2,375 2024 19,057 2,119 2025 16,334 2,074 2026 71,903 9,850 Total lease payments 204,590 23,395 Less: Imputed Interest (36,688 ) (4,704 ) Present value of lease liabilities $ 167,902 $ 18,691 The aggregate future maturities of lease payments for operating leases and finance leases as of September 30, 2020 are as follows (in thousands): Operating Leases Finance Leases 2021 $ 38,411 $ 4,282 2022 33,286 2,695 2023 25,599 2,375 2024 19,057 2,119 2025 16,334 2,074 2026 71,903 9,850 Total lease payments 204,590 23,395 Less: Imputed Interest (36,688 ) (4,704 ) Present value of lease liabilities $ 167,902 $ 18,691

EARNINGS PER SHARE EARNINGS PER

EARNINGS PER SHARE EARNINGS PER SHARE (Tables)	12 Months Ended
	Sep. 30, 2020
Earnings Per Share [Abstract]
Schedule of Earnings Per Share, Basic and Diluted	The following table is a reconciliation of the share amounts (in thousands) used in computing basic and diluted EPS for 2020, 2019 and 2018 : 2020 2019 2018 Common shares outstanding 56,130 46,806 45,675 Unallocated ESOP shares (2,058 ) (2,259 ) (2,477 ) Non-vested restricted stock (3,556 ) (3,420 ) (2,522 ) Impact of weighted average shares (7,928 ) (193 ) 329 Weighted average shares outstanding - basic 42,588 40,934 41,005 Incremental shares from stock based compensation 2,427 1,954 1,417 Weighted average shares outstanding - diluted 45,015 42,888 42,422

QUARTERLY FINANCIAL INFORMATI_2

QUARTERLY FINANCIAL INFORMATION (UNAUDITED) (Tables)	12 Months Ended
	Sep. 30, 2020
Quarterly Financial Information Disclosure [Abstract]
Schedule of Quarterly Financial Information	Quarterly results of continuing operations for 2020 and 2019 were as follows: Quarter ended Revenue Gross Profit Income from continuing operations Per Share - Basic Per Share - Diluted 2020 December 31, 2019 $ 548,438 $ 149,921 $ 10,612 $ 0.26 $ 0.24 March 31, 2020 566,350 152,032 895 0.02 0.02 June 30, 2020 632,061 165,003 21,831 0.52 0.50 September 30, 2020 660,673 174,470 20,091 0.44 0.41 $ 2,407,522 $ 641,426 $ 53,429 $ 1.25 $ 1.19 2019 December 31, 2018 $ 510,522 $ 139,780 $ 8,753 $ 0.21 $ 0.21 March 31, 2019 549,633 133,537 6,490 0.16 0.15 June 30, 2019 574,970 151,699 14,128 0.34 0.33 September 30, 2019 574,164 158,458 16,251 0.40 0.37 $ 2,209,289 $ 583,474 $ 45,622 $ 1.11 $ 1.06

REPORTABLE SEGMENTS (Tables)

REPORTABLE SEGMENTS (Tables)	12 Months Ended
	Sep. 30, 2020
Segment Reporting [Abstract]
Schedule of Segment Reporting Information, by Segment	The following table provides a reconciliation of Segment Adjusted EBITDA to Income before taxes and discontinued operations: For the Years Ended September 30, 2020 2019 2018 Segment Adjusted EBITDA: Consumer and Professional Products $ 104,053 $ 90,677 $ 77,061 Home and Building Products 153,631 120,161 100,339 Defense Electronics 25,228 35,104 36,063 Segment Adjusted EBITDA 282,912 245,942 213,463 Unallocated amounts, excluding depreciation (47,013 ) (46,302 ) (45,343 ) Adjusted EBITDA 235,899 199,640 168,120 Net interest expense (65,791 ) (67,260 ) (63,871 ) Depreciation and amortization (62,409 ) (61,848 ) (55,803 ) Restructuring charges (15,790 ) — — Loss from debt extinguishment (7,925 ) — — Acquisition contingent consideration 1,733 1,646 — Acquisition costs (2,960 ) — (7,597 ) Special dividend charges — — (3,220 ) Cost of life insurance benefit — — (2,614 ) Secondary equity offering costs — — (1,205 ) Income before taxes from continuing operations $ 82,757 $ 72,178 $ 33,810 Information on Griffon’s reportable segments from continuing operations is as follows: For the Years Ended September 30, REVENUE 2020 2019 2018 Consumer and Professional Products $ 1,139,233 $ 1,000,608 $ 953,612 Home and Building Products 927,313 873,640 697,969 Defense Electronics 340,976 335,041 326,337 Total consolidated net sales $ 2,407,522 $ 2,209,289 $ 1,977,918
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis	For the Years Ended September 30, DEPRECIATION and AMORTIZATION 2020 2019 2018 Segment: Consumer and Professional Products $ 32,788 $ 32,289 $ 30,816 Home and Building Products 18,361 18,334 13,717 Defense Electronics 10,645 10,667 10,801 Total segment depreciation and amortization 61,794 61,290 55,334 Corporate 615 558 469 Total consolidated depreciation and amortization $ 62,409 $ 61,848 $ 55,803 CAPITAL EXPENDITURES Segment: Consumer and Professional Products $ 23,321 $ 17,828 $ 23,040 Home and Building Products 17,499 16,498 13,547 Defense Electronics 7,830 10,492 10,941 Total segment 48,650 44,818 47,528 Corporate 348 543 2,610 Total consolidated capital expenditures $ 48,998 $ 45,361 $ 50,138 ASSETS At September 30, 2020 At September 30, 2019 Segment assets: Consumer and Professional Products $ 1,262,705 $ 1,070,510 Home and Building Products 606,785 571,216 Defense Electronics 329,128 347,575 Total segment assets 2,198,618 1,989,301 Corporate 248,902 82,429 Total continuing assets 2,447,520 2,071,730 Assets of discontinued operations 8,497 3,209 Consolidated total $ 2,456,017 $ 2,074,939
Disaggregation of Revenue	For the Year Ended September 30, 2019 Revenue by Geographic Area - Destination Consumer and Professional Products Home and Building Products Defense Electronics Total United States $ 690,772 $ 820,396 $ 226,095 $ 1,737,263 Europe 63,284 109 36,915 100,308 Canada 72,327 39,472 10,568 122,367 Australia 165,291 16 3,712 169,019 All other countries 8,934 13,647 57,751 80,332 Consolidated revenue $ 1,000,608 $ 873,640 $ 335,041 $ 2,209,289 Revenue from contracts with customers is disaggregated by end markets, segments and geographic location, as it more accurately depicts the nature and amount of the Company’s revenue. For the Year Ended September 30, 2020 For the Year Ended September 30, 2019 Residential repair and remodel $ 173,859 $ 140,369 Retail 575,947 528,279 Residential new construction 59,907 58,709 Industrial 40,285 45,129 International excluding North America 289,235 228,122 Total Consumer and Professional Products 1,139,233 1,000,608 Residential repair and remodel 467,112 439,287 Commercial construction 354,916 335,339 Residential new construction 105,285 99,014 Total Home and Building Products 927,313 873,640 U.S. Government 222,537 211,405 International 100,623 105,705 Commercial 17,816 17,931 Total Defense Electronics 340,976 335,041 Total Consolidated Revenue $ 2,407,522 $ 2,209,289 The following table presents revenue disaggregated by geography based on the location of the Company's customer: For the Year Ended September 30, 2020 Revenue by Geographic Area - Destination Consumer and Professional Products Home and Building Products Defense Electronics Total United States $ 769,100 $ 877,115 $ 234,382 $ 1,880,597 Europe 85,339 130 38,353 123,822 Canada 74,072 38,662 12,043 124,777 Australia 203,012 — 1,882 204,894 All other countries 7,710 11,406 54,316 73,432 Consolidated revenue $ 1,139,233 $ 927,313 $ 340,976 $ 2,407,522

OTHER COMPREHENSIVE INCOME (L_2

OTHER COMPREHENSIVE INCOME (LOSS) (Tables)	12 Months Ended
	Sep. 30, 2020
Other Comprehensive Income (Loss), Net of Tax [Abstract]
Comprehensive Income (Loss)	Total comprehensive income (loss) were as follows: For the Years Ended September 30, 2020 2019 2018 Net income $ 53,429 $ 37,287 $ 125,678 Other comprehensive income (loss), net of taxes (6,176 ) (31,804 ) 26,369 Comprehensive income (loss) $ 47,253 $ 5,483 $ 152,047 The amounts recognized in other comprehensive income (loss) were as follows: Years Ended September 30, 2020 2019 2018 Pre-tax Tax Net of tax Pre-tax Tax Net of tax Pre-tax Tax Net of tax Foreign currency translation adjustments $ 5,601 $ — $ 5,601 $ (8,460 ) $ — $ (8,460 ) $ 9,403 $ — $ 9,403 Pension and other defined benefit plans (14,955 ) 3,171 (11,784 ) (30,581 ) 7,526 (23,055 ) 24,081 (7,700 ) 16,381 Cash flow hedge 10 (3 ) 7 (413 ) 124 (289 ) 900 (315 ) 585 Total other comprehensive income (loss) $ (9,344 ) $ 3,168 $ (6,176 ) $ (39,454 ) $ 7,650 $ (31,804 ) $ 34,384 $ (8,015 ) $ 26,369
Accumulated Other Comprehensive Income (Loss)	The components of Accumulated other comprehensive income (loss) are as follows: At September 30, 2020 2019 Foreign currency translation $ (25,683 ) $ (31,284 ) Pension and other defined benefit plans (46,598 ) (34,814 ) Cash flow hedge 189 182 Total $ (72,092 ) $ (65,916 )
Amounts Reclassified From Accumulated Other Comprehensive Income (Loss)	Amounts reclassified from accumulated other comprehensive income (loss) to income (loss) were as follows: For the Years Ended September 30, Gain (Loss) 2020 2019 2018 Pension amortization $ (4,182 ) $ (902 ) $ (1,397 ) Cash flow hedges (2,163 ) 1,361 657 Total before tax (6,345 ) 459 (740 ) Tax 1,332 (96 ) 155 Net of tax $ (5,013 ) $ 363 $ (585 )

LEASES (Tables)

LEASES (Tables)	12 Months Ended
	Sep. 30, 2020
Leases [Abstract]
Components of Operating Lease Cost, Cash Flow Information, and Average Lease Terms and Discount Rates	Average lease terms and discount rates were as follows: September 30, 2020 Weighted-average remaining lease term (years) Operating Leases 8.3 Finance Leases 8.5 Weighted-average discount rate Operating Leases 4.38 % Finance Leases 5.51 % For the Year Ended September 30, 2020 Fixed (a) $ 38,554 Variable (a), (b) 7,822 Short-term (b) 5,606 Total $ 51,982 (a) Primarily related to common-area maintenance and property taxes. (b) Not recorded on the balance sheet. Fixed rent expense for all operating leases totaled approximately $37,068 and $35,726 in 2019 and 2018, respectively. Supplemental cash flow information were as follows: For the Year Ended September 30, 2020 Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows from operating leases $ 48,141 Financing cash flows from finance leases 4,122 Total $ 52,263
Supplemental Condensed Consolidated Balance Sheet Information	Supplemental Condensed Consolidated Balance Sheet information related to leases were as follows: At September 30, 2020 Operating Leases: Right of use assets: Operating right-of-use assets $ 161,627 Lease Liabilities: Current portion of operating lease liabilities $ 31,848 Long-term operating lease liabilities 136,054 Total operating lease liabilities $ 167,902 Finance Leases: Right of use assets: Property, plant and equipment, net (1) $ 18,774 Lease Liabilities: Notes payable and current portion of long-term debt $ 3,352 Long-term debt, net 15,339 Total financing lease liabilities $ 18,691 (1) Finance lease assets are recorded net of accumulated depreciation of $2,383 .
Aggregate Future Maturities of Lease Payments for Operating Leases	Aggregate future maturities of lease payments for operating leases and finance leases as of September 30, 2020 are as follows (in thousands): Operating Leases Finance Leases 2021 $ 38,411 $ 4,282 2022 33,286 2,695 2023 25,599 2,375 2024 19,057 2,119 2025 16,334 2,074 2026 71,903 9,850 Total lease payments 204,590 23,395 Less: Imputed Interest (36,688 ) (4,704 ) Present value of lease liabilities $ 167,902 $ 18,691 The aggregate future maturities of lease payments for operating leases and finance leases as of September 30, 2020 are as follows (in thousands): Operating Leases Finance Leases 2021 $ 38,411 $ 4,282 2022 33,286 2,695 2023 25,599 2,375 2024 19,057 2,119 2025 16,334 2,074 2026 71,903 9,850 Total lease payments 204,590 23,395 Less: Imputed Interest (36,688 ) (4,704 ) Present value of lease liabilities $ 167,902 $ 18,691
Aggregate Future Maturities of Lease Payments for Finance Leases	The aggregate future maturities of lease payments for operating leases and finance leases as of September 30, 2020 are as follows (in thousands): Operating Leases Finance Leases 2021 $ 38,411 $ 4,282 2022 33,286 2,695 2023 25,599 2,375 2024 19,057 2,119 2025 16,334 2,074 2026 71,903 9,850 Total lease payments 204,590 23,395 Less: Imputed Interest (36,688 ) (4,704 ) Present value of lease liabilities $ 167,902 $ 18,691

CONSOLIDATING GUARANTOR AND N_2

CONSOLIDATING GUARANTOR AND NON-GUARANTOR FINANCIAL INFORMATION (Tables)	12 Months Ended
	Sep. 30, 2020
Consolidating Guarantor And Non Guarantor Financial Information [Abstract]
Condensed Consolidating Balance Sheets	Parent Company Guarantor Companies Non-Guarantor Companies Elimination Consolidation CURRENT ASSETS Cash and equivalents $ 125,353 $ 35,685 $ 57,051 $ — $ 218,089 Accounts receivable, net of allowances — 293,943 54,181 — 348,124 Contract assets, net of progress payments — 80,572 3,854 — 84,426 Inventories — 347,473 66,352 — 413,825 Prepaid and other current assets 14,650 25,974 6,273 — 46,897 Assets of discontinued operations — — 2,091 — 2,091 Total Current Assets 140,003 783,647 189,802 — 1,113,452 PROPERTY, PLANT AND EQUIPMENT, net 1,182 296,082 46,700 — 343,964 OPERATING LEASE RIGHT-OF-USE ASSETS 9,209 129,813 22,605 — 161,627 GOODWILL — 377,060 65,583 — 442,643 INTANGIBLE ASSETS, net 93 217,317 137,618 — 355,028 INTERCOMPANY RECEIVABLE 568,124 704,415 257,013 (1,529,552 ) — EQUITY INVESTMENTS IN SUBSIDIARIES 1,724,821 784,644 3,176,855 (5,686,320 ) — OTHER ASSETS 12,585 25,953 (5,641 ) — 32,897 ASSETS OF DISCONTINUED OPERATIONS — — 6,406 — 6,406 Total Assets $ 2,456,017 $ 3,318,931 $ 3,896,941 $ (7,215,872 ) $ 2,456,017 CURRENT LIABILITIES Notes payable and current portion of long-term debt $ — $ 2,855 $ 7,067 $ — $ 9,922 Accounts payable and accrued liabilities 37,281 276,580 89,818 — 403,679 Current portion of operating lease liabilities 1,849 24,436 5,563 — 31,848 Liabilities of discontinued operations — — 3,797 — 3,797 Total Current Liabilities 39,130 303,871 106,245 — 449,246 LONG-TERM DEBT, net 995,636 15,992 25,414 — 1,037,042 LONG-TERM OPERATING LEASE LIABILITIES 8,415 110,061 17,578 — 136,054 INTERCOMPANY PAYABLES 683,076 397,846 459,599 (1,540,521 ) — OTHER LIABILITIES 29,609 85,731 11,170 — 126,510 LIABILITIES OF DISCONTINUED OPERATIONS — — 7,014 — 7,014 Total Liabilities 1,755,866 913,501 627,020 (1,540,521 ) 1,755,866 SHAREHOLDERS’ EQUITY 700,151 2,405,430 3,269,921 (5,675,351 ) 700,151 Total Liabilities and Shareholders’ Equity $ 2,456,017 $ 3,318,931 $ 3,896,941 $ (7,215,872 ) $ 2,456,017 CONDENSED CONSOLIDATING BALANCE SHEETS At September 30, 2019 Parent Company Guarantor Companies Non-Guarantor Companies Elimination Consolidation CURRENT ASSETS Cash and equivalents 1,649 25,217 45,511 — 72,377 Accounts receivable, net of allowances — 225,870 38,580 — 264,450 Contract assets, net of progress payments — 104,109 1,002 — 105,111 Inventories, net — 372,581 69,540 — 442,121 Prepaid and other current assets 8,238 25,610 6,951 — 40,799 Assets of discontinued operations — — 321 — 321 Total Current Assets 9,887 753,387 161,905 — 925,179 PROPERTY, PLANT AND EQUIPMENT, net 1,184 289,282 46,860 — 337,326 GOODWILL — 375,734 61,333 — 437,067 INTANGIBLE ASSETS, net 93 224,275 132,271 — 356,639 INTERCOMPANY RECEIVABLE 5,834 881,110 75,684 (962,628 ) — EQUITY INVESTMENTS IN SUBSIDIARIES 1,628,031 581,438 3,233,038 (5,442,507 ) — OTHER ASSETS 8,182 10,010 (2,352 ) — 15,840 ASSETS OF DISCONTINUED OPERATIONS — — 2,888 — 2,888 Total Assets 1,653,211 3,115,236 3,711,627 (6,405,135 ) 2,074,939 CURRENT LIABILITIES Notes payable and current portion of long-term debt — 3,075 7,450 — 10,525 Accounts payable and accrued liabilities 41,796 265,055 68,390 — 375,241 Liabilities of discontinued operations — — 4,333 — 4,333 Total Current Liabilities 41,796 268,130 80,173 — 390,099 LONG-TERM DEBT, net 1,040,449 3,119 50,181 — 1,093,749 INTERCOMPANY PAYABLES 71,634 466,792 444,557 (982,983 ) — OTHER LIABILITIES 21,569 73,411 15,017 — 109,997 LIABILITIES OF DISCONTINUED OPERATIONS — — 3,331 — 3,331 Total Liabilities 1,175,448 811,452 593,259 (982,983 ) 1,597,176 SHAREHOLDERS’ EQUITY 477,763 2,303,784 3,118,368 (5,422,152 ) 477,763 Total Liabilities and Shareholders’ Equity 1,653,211 3,115,236 3,711,627 (6,405,135 ) 2,074,939
Condensed Consolidating Statements of Operations and Comprehensive Income (Loss)	CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME (LOSS) For the Year Ended September 30, 2020 Parent Company Guarantor Companies Non-Guarantor Companies Elimination Consolidation Revenue $ — $ 1,938,972 $ 507,621 $ (39,071 ) $ 2,407,522 Cost of goods and services — 1,450,924 355,696 (40,524 ) 1,766,096 Gross profit — 488,048 151,925 1,453 641,426 Selling, general and administrative expenses 24,876 357,901 103,991 (370 ) 486,398 Income (loss) from operations (24,876 ) 130,147 47,934 1,823 155,028 Other income (expense) Interest income (expense), net (27,129 ) (38,301 ) (361 ) — (65,791 ) Loss on extinguishment of debt (7,925 ) — — — (7,925 ) Other, net (523 ) (7,946 ) 11,762 (1,848 ) 1,445 Total other income (expense) (35,577 ) (46,247 ) 11,401 (1,848 ) (72,271 ) Income (loss) before taxes (60,453 ) 83,900 59,335 (25 ) 82,757 Provision (benefit) for income taxes (11,907 ) 25,445 15,788 2 29,328 Income (loss) before equity in net income of subsidiaries (48,546 ) 58,455 43,547 (27 ) 53,429 Equity in net income (loss) of subsidiaries 101,975 43,505 58,455 (203,935 ) — Net income (loss) $ 53,429 $ 101,960 $ 102,002 $ (203,962 ) $ 53,429 Comprehensive income (loss) $ 47,253 $ 101,960 $ 102,002 $ (203,962 ) $ 47,253 CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME (LOSS) For the Year Ended September 30, 2019 Parent Company Guarantor Companies Non-Guarantor Companies Elimination Consolidation Revenue $ — $ 1,808,824 $ 437,542 $ (37,077 ) $ 2,209,289 Cost of goods and services — 1,353,663 310,707 (38,555 ) 1,625,815 Gross profit — 455,161 126,835 1,478 583,474 Selling, general and administrative expenses 22,566 327,306 97,661 (370 ) 447,163 Income (loss) from operations (22,566 ) 127,855 29,174 1,848 136,311 Other income (expense) Interest income (expense), net (27,883 ) (39,288 ) (89 ) — (67,260 ) Other, net (778 ) (17,699 ) 23,452 (1,848 ) 3,127 Total other income (expense) (28,661 ) (56,987 ) 23,363 (1,848 ) (64,133 ) Income (loss) before taxes (51,227 ) 70,868 52,537 — 72,178 Provision (benefit) for income taxes (7,425 ) 20,534 13,447 — 26,556 Income (loss) before equity in net income of subsidiaries (43,802 ) 50,334 39,090 — 45,622 Equity in net income (loss) of subsidiaries 81,089 44,303 50,334 (175,726 ) — Income (loss) from continuing operations 37,287 94,637 89,424 (175,726 ) 45,622 Income (loss) from operations of discontinued businesses — — (11,050 ) — (11,050 ) Provision (benefit) from income taxes — — (2,715 ) — (2,715 ) Income (loss) from discontinued operations — — (8,335 ) — (8,335 ) Net Income (loss) $ 37,287 $ 94,637 $ 81,089 $ (175,726 ) $ 37,287 Comprehensive income (loss) $ 5,483 $ 87,851 $ 87,875 $ (175,726 ) $ 5,483 CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME (LOSS) For the Year Ended September 30, 2018 Parent Company Guarantor Companies Non-Guarantor Companies Elimination Consolidation Revenue $ — $ 1,638,792 $ 367,149 $ (28,023 ) $ 1,977,918 Cost of goods and services — 1,250,261 245,687 (29,348 ) 1,466,600 Gross profit — 388,531 121,462 1,325 511,318 Selling, general and administrative expenses 37,540 290,475 90,872 (370 ) 418,517 Income (loss) from operations (37,540 ) 98,056 30,590 1,695 92,801 Other income (expense) Interest income (expense), net (23,911 ) (31,913 ) (8,047 ) — (63,871 ) Other, net (7,666 ) 125,531 (111,248 ) (1,737 ) 4,880 Total other income (expense) (31,577 ) 93,618 (119,295 ) (1,737 ) (58,991 ) Income (loss) before taxes from continuing operations (69,117 ) 191,674 (88,705 ) (42 ) 33,810 Provision (benefit) for income taxes (17,692 ) 9,546 8,743 (42 ) 555 Income (loss) before equity in net income of subsidiaries (51,425 ) 182,128 (97,448 ) — 33,255 Equity in net income (loss) of subsidiaries 177,103 (151,864 ) 182,128 (207,367 ) — Income (loss) from continuing operations 125,678 30,264 84,680 (207,367 ) 33,255 Income from operations of discontinued businesses — 119,981 — — 119,981 Provision (benefit) from income taxes — 27,558 — — 27,558 Loss from discontinued operations — 92,423 — — 92,423 Net income (loss) $ 125,678 $ 122,687 $ 84,680 $ (207,367 ) $ 125,678 Comprehensive income (loss) $ 152,047 $ 143,936 $ 81,389 $ (225,325 ) $ 152,047
Condensed Consolidating Statements of Cash Flow Statement	CONDENSED CONSOLIDATING STATEMENTS OF CASH FLOWS For the Year Ended September 30, 2020 Parent Company Guarantor Companies Non-Guarantor Companies Elimination Consolidation CASH FLOWS FROM OPERATING ACTIVITIES: Net income (loss) $ 53,429 $ 101,960 $ 102,002 $ (203,962 ) $ 53,429 Net cash provided by operating activities 23,114 55,353 58,562 — 137,029 CASH FLOWS FROM INVESTING ACTIVITIES: Acquisition of property, plant and equipment (348 ) (42,268 ) (6,382 ) — (48,998 ) Acquired business, net of cash acquired — — (10,531 ) — (10,531 ) Proceeds from sale of assets — 345 7 — 352 Investment purchases (130 ) — — — (130 ) Net cash used in investing activities (478 ) (41,923 ) (16,906 ) — (59,307 ) CASH FLOWS FROM FINANCING ACTIVITIES: Proceeds from issuance of common stock 178,165 — — — 178,165 Purchase of shares for treasury (7,479 ) — — — (7,479 ) Proceeds from long-term debt 1,234,723 — 5,357 — 1,240,080 Payments of long-term debt (1,272,688 ) (3,421 ) (32,806 ) — (1,308,915 ) Financing costs (17,384 ) — — — (17,384 ) Acquisition costs — — (1,733 ) — (1,733 ) Dividends paid (14,529 ) — — — (14,529 ) Other, net 260 580 (855 ) — (15 ) Net cash provided by (used in) financing activities 101,068 (2,841 ) (30,037 ) — 68,190 CASH FLOWS FROM DISCONTINUED OPERATIONS: Net cash used in discontinued operations — — (2,577 ) — (2,577 ) Effect of exchange rate changes on cash and equivalents — (121 ) 2,498 — 2,377 NET INCREASE (DECREASE) IN CASH AND EQUIVALENTS 123,704 10,468 11,540 — 145,712 CASH AND EQUIVALENTS AT BEGINNING OF PERIOD 1,649 25,217 45,511 — 72,377 CASH AND EQUIVALENTS AT END OF PERIOD $ 125,353 $ 35,685 $ 57,051 $ — $ 218,089 CONDENSED CONSOLIDATING STATEMENTS OF CASH FLOWS For the Year Ended September 30, 2019 Parent Company Guarantor Companies Non-Guarantor Companies Elimination Consolidation CASH FLOWS FROM OPERATING ACTIVITIES: Net income (loss) $ 37,287 $ 94,637 $ 81,089 $ (175,726 ) $ 37,287 Net (income) loss from discontinued operations — — 8,335 — 8,335 Net cash provided by (used in) operating activities 42,159 41,992 29,807 — 113,958 CASH FLOWS FROM INVESTING ACTIVITIES: Acquisition of property, plant and equipment (542 ) (38,872 ) (5,947 ) — (45,361 ) Acquired business, net of cash acquired (9,219 ) — — — (9,219 ) Proceeds from sale of business (9,500 ) — — — (9,500 ) Insurance payments (10,604 ) — — — (10,604 ) Proceeds from sale of assets — 254 26 — 280 Investment purchases (149 ) — — — (149 ) Net cash provided by (used in) investing activities (30,014 ) (38,618 ) (5,921 ) — (74,553 ) CASH FLOWS FROM FINANCING ACTIVITIES: Purchase of shares for treasury (1,478 ) — — — (1,478 ) Proceeds from long-term debt 163,297 — 38,451 — 201,748 Payments of long-term debt (173,345 ) (2,973 ) (41,930 ) — (218,248 ) Change in short-term borrowings — (366 ) — — (366 ) Financing costs (1,090 ) — — — (1,090 ) Contingent consideration for acquired businesses — — (1,686 ) — (1,686 ) Dividends paid (13,676 ) — — — (13,676 ) Other, net (180 ) 8,830 (8,830 ) — (180 ) Net cash provided by (used in) financing activities (26,472 ) 5,491 (13,995 ) — (34,976 ) CASH FLOWS FROM DISCONTINUED OPERATIONS: Net cash used in discontinued operations — — (2,123 ) — (2,123 ) Effect of exchange rate changes on cash and equivalents — (1 ) 314 — 313 NET INCREASE IN CASH AND EQUIVALENTS (14,327 ) 8,864 8,082 — 2,619 CASH AND EQUIVALENTS AT BEGINNING OF PERIOD 15,976 16,353 37,429 — 69,758 CASH AND EQUIVALENTS AT END OF PERIOD $ 1,649 $ 25,217 $ 45,511 $ — $ 72,377 CONDENSED CONSOLIDATING STATEMENTS OF CASH FLOWS For the Year Ended September 30, 2018 Parent Company Guarantor Companies Non-Guarantor Companies Elimination Consolidation CASH FLOWS FROM OPERATING ACTIVITIES: Net income (loss) $ 125,678 $ 122,687 $ 84,680 $ (207,367 ) $ 125,678 Net income (loss) from discontinued operations — (92,423 ) — — (92,423 ) Net cash provided by (used in) operating activities 381,417 (405,174 ) 108,981 (27,032 ) 58,192 CASH FLOWS FROM INVESTING ACTIVITIES: Acquisition of property, plant and equipment (544 ) (41,531 ) (8,063 ) — (50,138 ) Acquired business, net of cash acquired (368,936 ) (4,843 ) (57,153 ) — (430,932 ) Proceeds from sale of business — 474,727 — — 474,727 Insurance proceeds 8,254 — — — 8,254 Proceeds from sale of property, plant and equipment — 62 601 — 663 Net cash used in investing activities (361,226 ) 428,415 (64,615 ) — 2,574 CASH FLOWS FROM FINANCING ACTIVITIES: Purchase of shares for treasury (45,605 ) — — — (45,605 ) Proceeds from long-term debt 411,623 2,125 29,310 — 443,058 Payments of long-term debt (269,478 ) (5,403 ) (26,112 ) — (300,993 ) Change in short-term borrowings — 144 — — 144 Financing costs (7,793 ) — — — (7,793 ) Purchase of ESOP shares — — — — — Dividends paid (49,797 ) — — — (49,797 ) Other, net (46,405 ) 4,733 14,691 27,032 51 Net cash provided by (used in) financing activities (7,455 ) 1,599 17,889 27,032 39,065 CASH FLOWS FROM DISCONTINUED OPERATIONS: Net cash provided by (used in) discontinued operations — (16,394 ) (62,533 ) — (78,927 ) Effect of exchange rate changes on cash and equivalents — (159 ) 1,332 — 1,173 NET DECREASE IN CASH AND EQUIVALENTS 12,736 8,287 1,054 — 22,077 CASH AND EQUIVALENTS AT BEGINNING OF PERIOD 3,240 8,066 36,375 — 47,681 CASH AND EQUIVALENTS AT END OF PERIOD $ 15,976 $ 16,353 $ 37,429 $ — $ 69,758

DESCRIPTION OF BUSINESS AND S_3

DESCRIPTION OF BUSINESS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) $ / shares in Units, $ in Thousands, $ in Thousands

Aug. 21, 2020USD ($)shares

Aug. 21, 2020USD ($)shares

Aug. 18, 2020USD ($)shares

Feb. 19, 2020USD ($)

Aug. 31, 2020USD ($)shares

Sep. 30, 2020USD ($)segment$ / shares

Sep. 30, 2019USD ($)$ / shares

Sep. 30, 2018USD ($)

Nov. 12, 2020USD ($)

Sep. 30, 2020AUD ($)

Sep. 30, 2020USD ($)

Jun. 08, 2020USD ($)

Jan. 30, 2020USD ($)

Jan. 29, 2020USD ($)

Nov. 30, 2019USD ($)

Oct. 01, 2019USD ($)

Sep. 30, 2019AUD ($)

Sep. 30, 2019USD ($)

Sep. 30, 2019CAD ($)

Feb. 06, 2018USD ($)

Sep. 30, 2017USD ($)

Description Of Business And Summary Of Significant Accounting Policies [Line Items]

Non-service cost components of net periodic benefit cost (credit)

$ (1,559,000)

$ (3,148,000)

$ (3,649,000)

Sale of stock, number of shares issued (in shares) | shares

700,000

8,700,000

8,000,000

8,700,000

Net process from sale of stock

$ 14,335,000

$ 178,165,000

$ 163,830,000

$ 178,165,000

Number of reportable segments | segment

3

Cash in non U.S. bank accounts

$ 55,000,000

$ 34,200,000

Fair value of insurance contracts

3,436,000

Accumulated other comprehensive income (loss), foreign currency translation adjustment, net of tax

5,601,000

(8,460,000)

Defined benefit plan, fair value of plan assets

147,145,000

145,610,000

Change in retained earnings

474,391,000

700,151,000

477,763,000

$ 398,808,000

Percentage of performance obligations recognized at a point in time

86.00%

Percentage of performance obligations recognized over time

14.00%

Customer program reserves and cash discounts netted against accounts receivable

27,607,000

17,322,000

Contract assets, before allowance for credit Loss, noncurrent

7,500,000

13,100,000

Depreciation, depletion and amortization, nonproduction

$ 52,819,000

51,926,000

46,733,000

Accumulated capitalized interest costs

2,896,000

2,520,000

2,925,000

Original cost of fully depreciated property plant and equipment

262,255,000

Fair value projection, term

5 years

Fair value terminal value (in percentage)

3.00%

Operating right-of-use assets

161,627,000

Lease liabilities

167,902,000

Goodwill, impairment loss

$ 0

0

0

Research and development arrangement, contract to perform for others, costs incurred, gross

15,400,000

15,400,000

15,400,000

Selling, general and administrative expenses

486,398,000

447,163,000

418,517,000

Selling, General and Administrative Expenses

Description Of Business And Summary Of Significant Accounting Policies [Line Items]

Depreciation

$ 19,656,000

$ 19,026,000

16,306,000

U.S. Government

Description Of Business And Summary Of Significant Accounting Policies [Line Items]

Percentage of consolidated accounts receivable

9.00%

Home Depot

Description Of Business And Summary Of Significant Accounting Policies [Line Items]

Percentage of consolidated accounts receivable

18.00%

Fair Value, Inputs, Level 2 | Estimate of Fair Value Measurement

Description Of Business And Summary Of Significant Accounting Policies [Line Items]

Trading securities

1,703,000

1,518,000

Fair Value, Inputs, Level 2 | Portion at other than Fair Value Measurement

Description Of Business And Summary Of Significant Accounting Policies [Line Items]

Trading securities

1,000,000

1,000,000

Senior Notes Due 2028

Description Of Business And Summary Of Significant Accounting Policies [Line Items]

Debt instrument, face amount

$ 850,000,000

$ 150,000,000

Stated percentage

5.75%

Issuance price, percentage

100.25%

Senior Notes Due 2028 | Fair Value, Inputs, Level 1

Description Of Business And Summary Of Significant Accounting Policies [Line Items]

Long-term debt, fair value

1,040,000,000

Senior Notes Due 2022

Description Of Business And Summary Of Significant Accounting Policies [Line Items]

Stated percentage

5.25%

Extinguishment of debt, amount

$ 1,000,000,000

Minimum

Description Of Business And Summary Of Significant Accounting Policies [Line Items]

Fair value discount rates (in percentage)

7.10%

Finite-lived intangible asset, useful life

8 years

Minimum | Building and Building Improvements

Description Of Business And Summary Of Significant Accounting Policies [Line Items]

Property, plant and equipment, useful life

25 years

Minimum | Machinery and equipment

Description Of Business And Summary Of Significant Accounting Policies [Line Items]

Property, plant and equipment, useful life

2 years

Maximum

Description Of Business And Summary Of Significant Accounting Policies [Line Items]

Maturity period of highly liquid investments

3 months

Fair value discount rates (in percentage)

9.00%

Finite-lived intangible asset, useful life

25 years

Maximum | Building and Building Improvements

Description Of Business And Summary Of Significant Accounting Policies [Line Items]

Property, plant and equipment, useful life

40 years

Maximum | Machinery and equipment

Description Of Business And Summary Of Significant Accounting Policies [Line Items]

Property, plant and equipment, useful life

15 years

Australian Dollar Contracts | Designated as hedging instrument

Description Of Business And Summary Of Significant Accounting Policies [Line Items]

Derivative, notional amount

$ 32,000

$ 14,000

Contracts weighted average rate price (in dollars per share) | $ / shares

$ 1.41

$ 1.48

Accumulated other comprehensive income (loss), foreign currency translation adjustment, before tax

168,000

327,000

Accumulated other comprehensive income (loss), foreign currency translation adjustment, net of tax

109,000

213,000

Gain (loss) on hedging activity

$ (2,163,000)

$ 1,361,000

Australian Dollar Contracts | Minimum | Designated as hedging instrument

Description Of Business And Summary Of Significant Accounting Policies [Line Items]

Contracts expiration days

30 days

Australian Dollar Contracts | Maximum | Designated as hedging instrument

Description Of Business And Summary Of Significant Accounting Policies [Line Items]

Contracts expiration days

146 days

Canadian Dollar Contract | Not Designated as Hedging Instrument

Description Of Business And Summary Of Significant Accounting Policies [Line Items]

Derivative, notional amount

7,900,000

$ 3,500

Contracts weighted average rate price (in dollars per share) | $ / shares

$ 1.33

$ 1.32

Fair value gain (loss) on foreign currency contract not qualify for hedge accounting

$ (92,000)

$ 14,000

Canadian Dollar Contract | Fair Value, Inputs, Level 2 | Not Designated as Hedging Instrument | Other Income

Description Of Business And Summary Of Significant Accounting Policies [Line Items]

Gain (loss) on sale of derivatives

$ 189,000

68,000

Canadian Dollar Contract | Minimum | Not Designated as Hedging Instrument

Description Of Business And Summary Of Significant Accounting Policies [Line Items]

Term of contract

30 days

Canadian Dollar Contract | Maximum | Not Designated as Hedging Instrument

Description Of Business And Summary Of Significant Accounting Policies [Line Items]

Term of contract

360 days

Great Britain Pound Contracts | Not Designated as Hedging Instrument

Description Of Business And Summary Of Significant Accounting Policies [Line Items]

Derivative, notional amount

5,400,000

Fair value gain (loss) on foreign currency contract not qualify for hedge accounting

$ 39,000

Great Britain Pound Contracts | Fair Value, Inputs, Level 2 | Not Designated as Hedging Instrument | Other Income

Description Of Business And Summary Of Significant Accounting Policies [Line Items]

Gain (loss) on sale of derivatives

$ 0

Great Britain Pound Contracts | Minimum | Not Designated as Hedging Instrument

Description Of Business And Summary Of Significant Accounting Policies [Line Items]

Term of contract

2 days

Great Britain Pound Contracts | Maximum | Not Designated as Hedging Instrument

Description Of Business And Summary Of Significant Accounting Policies [Line Items]

Contracts weighted average rate price (in dollars per share) | $ / shares

$ 0.77

Term of contract

208 days

Foreign currency translation adjustments

Description Of Business And Summary Of Significant Accounting Policies [Line Items]

Change in retained earnings

$ (25,683,000)

$ (31,284,000)

Shipping and Handling

Description Of Business And Summary Of Significant Accounting Policies [Line Items]

Selling, general and administrative expenses

$ 54,500,000

53,500,000

41,700,000

Advertising

Description Of Business And Summary Of Significant Accounting Policies [Line Items]

Selling, general and administrative expenses

$ 19,000,000

$ 20,000,000

21,000,000

Cumulative Effect, Period of Adoption, Adjustment

Description Of Business And Summary Of Significant Accounting Policies [Line Items]

Change in retained earnings

$ (5,618,000)

Operating right-of-use assets

$ 163,552,000

Lease liabilities

$ 163,676,000

Revolver Due 2025

Description Of Business And Summary Of Significant Accounting Policies [Line Items]

Maximum borrowing capacity

$ 400,000,000

$ 350,000,000

PPC | Discontinued Operations, Disposed of by Sale

Description Of Business And Summary Of Significant Accounting Policies [Line Items]

Disposal group, including discontinued operation, consideration

$ 465,000,000

One Time Charges

Description Of Business And Summary Of Significant Accounting Policies [Line Items]

Restructuring and related cost

$ 35,000,000

One Time Charges | Subsequent Event

Description Of Business And Summary Of Significant Accounting Policies [Line Items]

Restructuring and related cost

$ 65,000,000

Capital Investments

Description Of Business And Summary Of Significant Accounting Policies [Line Items]

Restructuring and related cost

$ 40,000,000

Capital Investments | Subsequent Event

Description Of Business And Summary Of Significant Accounting Policies [Line Items]

Restructuring and related cost

65,000,000

Employee Severance and Facility Closing | Subsequent Event

Description Of Business And Summary Of Significant Accounting Policies [Line Items]

Restructuring and related cost

46,000,000

Personnel Related Costs | Subsequent Event

Description Of Business And Summary Of Significant Accounting Policies [Line Items]

Restructuring and related cost

26,000,000

Facilities, Exit Costs and Other | Subsequent Event

Description Of Business And Summary Of Significant Accounting Policies [Line Items]

Restructuring and related cost

20,000,000

Asset Write-Downs | Subsequent Event

Description Of Business And Summary Of Significant Accounting Policies [Line Items]

Restructuring and related cost

$ 19,000,000

Accounting Standards Update 2016-02

Description Of Business And Summary Of Significant Accounting Policies [Line Items]

Accounting Standards Update [Extensible List]

us-gaap:AccountingStandardsUpdate201602Member

REVENUE - Narrative (Details)

REVENUE - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Percentage of performance obligations recognized at a point in time	86.00%
Percentage of performance obligations recognized over time	14.00%
Favorable (unfavorable) catch-up adjustments to income from operations	$ (10,650)	$ (4,500)	$ 1,400
Accumulated estimated costs to complete loss contracts	10,800
Contract assets, net of progress payments	84,426	105,111
Decrease in contract assets balance	(20,685)
Contract assets, before allowance for credit Loss, noncurrent	7,500	13,100
Billings in excess of costs	24,386	$ 26,259
Increase (decrease) in contract liability	$ (1,873)
Minimum | Construction and Professional Products and Home and Building Products Segments
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Payment term	15 days
Maximum | Construction and Professional Products and Home and Building Products Segments
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Payment term	90 days

REVENUE - Transaction price all

REVENUE - Transaction price allocated to the remaining performance obligations (Details) $ in Thousands	Sep. 30, 2020USD ($)
Revenue from Contract with Customer [Abstract]
Remaining performance obligations (backlog)	$ 380,000
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-10-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligations (backlog), percentage to to be satisfied by the end of the year	67.00%
Remaining performance obligations (backlog), expected timing of satisfaction, period

ACQUISITIONS (Details)

ACQUISITIONS (Details) £ in Thousands, $ in Thousands	Nov. 29, 2019GBP (£)	Nov. 29, 2019USD ($)	Jun. 04, 2018USD ($)	Feb. 13, 2018GBP (£)	Feb. 13, 2018USD ($)	Nov. 06, 2017USD ($)	Oct. 02, 2017USD ($)	Sep. 30, 2020USD ($)	Mar. 31, 2020USD ($)	Sep. 30, 2019USD ($)	Sep. 30, 2020USD ($)	Sep. 30, 2019USD ($)	Sep. 30, 2018USD ($)
Business Acquisition [Line Items]
Goodwill								$ 442,643		$ 437,067	$ 442,643	$ 437,067	$ 439,395
Contingent consideration earned								$ (1,403)		$ 1,333	1,733	1,646	0
Acquisition related costs									$ 2,321		$ 2,960	$ 0
CornellCookson
Business Acquisition [Line Items]
Revenues													66,654
Selling, General and Administrative Expenses
Business Acquisition [Line Items]
Acquisition related costs													6,097
Cost of Sales
Business Acquisition [Line Items]
Acquisition related costs													$ 1,500
Vatre Group Limited
Business Acquisition [Line Items]
Business acquisition, percentage of voting interests acquired	100.00%
Business combination, consideration transferred	£ 8,750	$ 10,500
Goodwill | £	3,449
Intangible assets | £	3,454
Inventories | £	2,914
Accounts receivable | £	2,492
Accounts payable and other accrued liabilities | £	£ 3,765
CornellCookson
Business Acquisition [Line Items]
Business acquisition, percentage of voting interests acquired			100.00%
Business combination, consideration transferred			$ 180,000
Goodwill			43,183
Intangible assets			67,600
Inventories			12,336
Accounts receivable			30,400
Working capital adjustment			12,426
Definite-lived intangibles			14,100
Property, plant and equipment			$ 49,426
Kelkay
Business Acquisition [Line Items]
Business acquisition, percentage of voting interests acquired					100.00%
Business combination, consideration transferred				£ 40,452	$ 56,118
Contingent consideration					7,000
Contingent consideration earned | £				£ 2,200
Accounts receivable and inventory					8,894
Land acquired					8,241
Kelkay | Trade Names
Business Acquisition [Line Items]
Definite-lived intangibles					19,000
Kelkay | Customer Relationships
Business Acquisition [Line Items]
Definite-lived intangibles					$ 6,640
Harper Brush Works
Business Acquisition [Line Items]
Business combination, consideration transferred						$ 4,383
Intangible assets						2,300
Accounts receivable						3,900
Property, plant and equipment						$ 900
ClosetMaid LLC
Business Acquisition [Line Items]
Business acquisition, percentage of voting interests acquired							100.00%
Business combination, consideration transferred							$ 185,700
Goodwill							70,159
Intangible assets							74,580
Inventories							28,411
Accounts receivable							32,234
Definite-lived intangibles							26,840
Property, plant and equipment							$ 47,464

ACQUISITIONS (Details) - Acquis

ACQUISITIONS (Details) - Acquisition of CornellCookson, Schedule of Assets Acquired and Liabilities Assumed (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018	Jun. 04, 2018
Business Acquisition [Line Items]
Goodwill	$ 442,643	$ 437,067	$ 439,395
CornellCookson
Business Acquisition [Line Items]
Accounts receivable				$ 30,400
Inventories				12,336
Property, plant and equipment				49,426
Goodwill				43,183
Intangible assets				67,600
Other current and non-current assets				2,648
Total assets acquired				205,593
Accounts payable and accrued liabilities				12,507
Long-term liabilities				660
Total liabilities assumed				13,167
Total				192,426
Receivables gross				30,818
Allowance for accounts receivable				418
Inventory, gross				13,434
Inventory valuation reserves				$ 1,098

ACQUISITIONS (Details) - Schedu

ACQUISITIONS (Details) - Schedule of Intangible Assets Acquired in Cornell Cookson Acquisition (Details) - USD ($) $ in Thousands	Jun. 04, 2018	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Business Acquisition [Line Items]
Goodwill		$ 442,643	$ 437,067	$ 439,395
CornellCookson
Business Acquisition [Line Items]
Goodwill	$ 43,183
Indefinite-lived intangibles	53,500
Definite-lived intangibles	$ 14,100
Amortization period (years)	12 years
Total goodwill and intangible assets	$ 110,783

ACQUISITIONS (Details) - Summar

ACQUISITIONS (Details) - Summary of Fair Values of Assets Acquired - USD ($) $ in Thousands	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018	Oct. 02, 2017
Business Acquisition [Line Items]
Goodwill	$ 442,643	$ 437,067	$ 439,395
ClosetMaid LLC
Business Acquisition [Line Items]
Accounts receivable				$ 32,234
Inventories				28,411
Property, plant and equipment				47,464
Goodwill				70,159
Intangible assets				74,580
Other current and non-current assets				3,852
Total assets acquired				256,700
Accounts payable and accrued liabilities				68,251
Long-term liabilities				2,720
Total liabilities assumed				70,971
Total				185,729
Receivables gross				32,956
Allowance for accounts receivable				722
Inventory step-up				$ 1,500

ACQUISITIONS (Details) - Summ_2

ACQUISITIONS (Details) - Summary of Goodwill and Intangible Asset Classifications - USD ($) $ in Thousands	Oct. 02, 2017	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Business Acquisition [Line Items]
Goodwill		$ 442,643	$ 437,067	$ 439,395
ClosetMaid LLC
Business Acquisition [Line Items]
Goodwill	$ 70,159
Indefinite-lived intangibles	47,740
Definite-lived intangibles	26,840
Total goodwill and intangible assets	$ 144,739
Amortization period (years)	21 years

INVENTORIES (Details) - Summary

INVENTORIES (Details) - Summary of inventories stated at lower cost - USD ($) $ in Thousands	Sep. 30, 2020	Sep. 30, 2019
Inventory Disclosure [Abstract]
Raw materials and supplies	$ 135,083	$ 121,791
Work in process	81,624	93,830
Finished goods	197,118	226,500
Total	$ 413,825	$ 442,121

PROPERTY, PLANT AND EQUIPMENT_2

PROPERTY, PLANT AND EQUIPMENT (Details) - Summary of property plant and equipment - USD ($) $ in Thousands	Sep. 30, 2020	Sep. 30, 2019
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 815,517
Property, plant and equipment, gross		$ 763,542
Accumulated depreciation and amortization	(471,553)
Accumulated depreciation and amortization		(426,216)
Total	343,964
Total		337,326
Land, building and building improvements
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	167,005
Property, plant and equipment, gross		133,036
Machinery and equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	595,126
Property, plant and equipment, gross		580,698
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 53,386
Property, plant and equipment, gross		$ 49,808

GOODWILL AND OTHER INTANGIBLE_2

GOODWILL AND OTHER INTANGIBLES (Details) - Summary of changes in carrying value of goodwill - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 437,067	$ 439,395
Goodwill from acquisitions	4,451	300
Reallocation of Goodwill		0
Foreign currency translation adjustments	1,125	(2,628)
Goodwill, ending balance	442,643	437,067
Consumer and Professional Products
Goodwill [Roll Forward]
Goodwill, beginning balance	227,269	378,046
Goodwill from acquisitions	4,451	0
Reallocation of Goodwill		(148,076)
Foreign currency translation adjustments	1,125	(2,701)
Goodwill, ending balance	232,845	227,269
Home and Building Products
Goodwill [Roll Forward]
Goodwill, beginning balance	191,253	42,804
Goodwill from acquisitions	0	300
Reallocation of Goodwill		148,076
Foreign currency translation adjustments	0	73
Goodwill, ending balance	191,253	191,253
Defense Electronics
Goodwill [Roll Forward]
Goodwill, beginning balance	18,545	18,545
Goodwill from acquisitions	0	0
Reallocation of Goodwill		0
Foreign currency translation adjustments	0	0
Goodwill, ending balance	$ 18,545	$ 18,545

GOODWILL AND OTHER INTANGIBLE_3

GOODWILL AND OTHER INTANGIBLES (Details) - Summary of gross carrying value and accumulated amortization of intangible assets - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 205,404	$ 202,682
Trademarks	224,640	219,069
Total intangible assets	430,044	421,751
Accumulated Amortization	75,016	65,112
Customer Relationships
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	185,940	183,515
Accumulated Amortization	$ 66,656	57,783
Average Life (Years)	23 years
Unpatented technology
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 19,464	19,167
Accumulated Amortization	$ 8,360	$ 7,329
Average Life (Years)	13 years

GOODWILL AND OTHER INTANGIBLE_4

GOODWILL AND OTHER INTANGIBLES (Details) - USD ($)	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Goodwill [Line Items]
Goodwill, impairment loss	$ 0	$ 0	$ 0
Reallocation of goodwill		0
Amortization expense	9,590,000	9,922,000	$ 9,070,000
Amortization expense estimated for 2021	9,443,000
Amortization expense estimated for 2022	9,436,000
Amortization expense estimated for 2023	9,357,000
Amortization expense estimated for 2024	9,331,000
Amortization expense estimated for 2025	9,331,000
Amortization expense estimated thereafter	$ 83,490,000
Consumer and Professional Products
Goodwill [Line Items]
Reallocation of goodwill		(148,076,000)
Home and Building Products (HBP)
Goodwill [Line Items]
Reallocation of goodwill		$ 148,076,000
Accounting Standards Update 2017-04
Goodwill [Line Items]
Accounting Standards Update [Extensible List]	us-gaap:AccountingStandardsUpdate201704Member

DISCONTINUED OPERATIONS (Detail

DISCONTINUED OPERATIONS (Details) - USD ($)	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018	Feb. 06, 2018	Nov. 15, 2017
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Discontinued operation, claims dispute settlement		$ 11,050,000
Discontinued operation, claims dispute settlement, net of tax		8,335,000
Discontinued Operations, Disposed of by Sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal group, post-close adjustment, gross	$ 9,500,000
Disposal group, post-close adjustment, net	7,085,000
Installation Services
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Revenue	0	0	$ 0
PPC | Discontinued Operations, Disposed of by Sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal group, including discontinued operation, consideration				$ 465,000,000
Gain on sale of business	112,964,000
Gain on sale of business net of tax	81,041,000
Plastics | Discontinued Operations, Disposed of by Sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal group, including discontinued operation, consideration				$ 465,000,000
Gain on sale of business	0	112,964,000
Revenue	$ 0	$ 166,262,000
Plastics | Discontinued Operations, Held-for-sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal group, including discontinued operation, consideration					$ 465,000,000

DISCONTINUED OPERATIONS - Balan

DISCONTINUED OPERATIONS - Balance Sheets Information (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Sep. 30, 2019
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Other long-term assets	$ 6,406	$ 2,888
Total assets of discontinued operations	8,497	3,209
Other long-term liabilities	7,014	3,331
Discontinued and Disposed Groups | Discontinued Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Prepaid and other current assets	2,091	321
Other long-term assets	6,406	2,888
Total assets of discontinued operations	8,497	3,209
Accrued liabilities	3,797	4,333
Other long-term liabilities	7,014	3,331
Total liabilities of discontinued operations	$ 10,811	$ 7,664

DISCONTINUED OPERATIONS - Incom

DISCONTINUED OPERATIONS - Income Statement Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Income (loss) from discontinued operations	$ 0	$ (8,335)	$ 92,423
Plastics | Discontinued Operations, Disposed of by Sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Revenue	0	166,262
Cost of goods and services	0	132,100
Gross profit	0	34,162
Selling, general and administrative expenses	9,500	26,303
Restructuring charges	0	0
Total operating expenses	9,500	26,303
Income from discontinued operations	(9,500)	7,859
Gain on sale of business	0	112,964
Interest expense, net	0	(155)
Other, net	0	(687)
Total other income (expense)	0	112,122
Income (loss) from discontinued operations	$ (9,500)	$ 119,981

ACCRUED LIABILITIES (Details) -

ACCRUED LIABILITIES (Details) - Schedule of accrued liabilities - USD ($) $ in Thousands	Sep. 30, 2020	Sep. 30, 2019
Payables and Accruals [Abstract]
Compensation	$ 83,308	$ 61,639
Interest	4,371	4,501
Warranties and rebates	18,687	13,171
Insurance	10,997	11,996
Rent, utilities and freight	8,816	5,326
Income and other taxes	14,707	7,814
Marketing and advertising	7,968	4,417
Restructuring	2,965	0
Other	19,753	15,801
Total	$ 171,572	$ 124,665

RESTRUCTURING CHARGES - Narrati

RESTRUCTURING CHARGES - Narrative (Details)	Nov. 12, 2020USD ($)position	Sep. 30, 2020USD ($)	Jun. 30, 2020USD ($)	Mar. 31, 2020USD ($)	Dec. 31, 2019USD ($)	Sep. 30, 2020USD ($)position	Nov. 30, 2019USD ($)
Restructuring Cost and Reserve [Line Items]
Restructuring charges		$ 3,488,000	$ 1,224,000	$ 3,005,000	$ 4,148,000
Non-cash charges						$ 4,692,000
Impairment charge, operating lease						1,968,000
Impairment charge, leasehold improvements						671,000
One Time Charges
Restructuring Cost and Reserve [Line Items]
Restructuring and related cost, expected cost							$ 35,000,000
Capital Investments
Restructuring Cost and Reserve [Line Items]
Restructuring and related cost, expected cost							40,000,000
Personnel Related Costs
Restructuring Cost and Reserve [Line Items]
Non-cash charges						0
Facilities, Exit Costs and Other
Restructuring Cost and Reserve [Line Items]
Non-cash charges						0
Subsequent Event | One Time Charges
Restructuring Cost and Reserve [Line Items]
Restructuring and related cost, expected cost	$ 65,000,000
Subsequent Event | Capital Investments
Restructuring Cost and Reserve [Line Items]
Restructuring and related cost, expected cost	65,000,000
Subsequent Event | Employee Severance and Facility Closing
Restructuring Cost and Reserve [Line Items]
Restructuring and related cost, expected cost	46,000,000
Subsequent Event | Personnel Related Costs
Restructuring Cost and Reserve [Line Items]
Restructuring and related cost, expected cost	26,000,000
Subsequent Event | Facilities, Exit Costs and Other
Restructuring Cost and Reserve [Line Items]
Restructuring and related cost, expected cost	20,000,000
Subsequent Event | Asset Write-Downs
Restructuring Cost and Reserve [Line Items]
Restructuring and related cost, expected cost	$ 19,000,000
Telephonics Corporation | Voluntary Employee Retirement Plan | Capital Investments
Restructuring Cost and Reserve [Line Items]
Restructuring charges						4,000,000
Telephonics Corporation | Voluntary Employee Retirement Plan | Personnel Related Costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges		$ 2,120,000
Telephonics Corporation | Voluntary Employee Retirement Plan | Subsequent Event
Restructuring Cost and Reserve [Line Items]
Expected number of headcount reduced | position	90
Telephonics Corporation | Voluntary Employee Retirement Plan | Subsequent Event | Personnel Related Costs
Restructuring Cost and Reserve [Line Items]
Restructuring and related cost, expected cost	$ 4,500,000
Consumer and Professional Products
Restructuring Cost and Reserve [Line Items]
Restructuring charges						13,669,000
Non-cash charges						4,692,000
Impairment charge, operating lease						1,968,000
Impairment charge, leasehold improvements						671,000
Impairment of inventory						304,000
Impairment of machinery and equipment						$ 1,749,000
Number of headcount reduced | position						167
Consumer and Professional Products | One Time Charges
Restructuring Cost and Reserve [Line Items]
Restructuring and related cost, expected cost							35,000,000
Consumer and Professional Products | Capital Investments
Restructuring Cost and Reserve [Line Items]
Restructuring and related cost, expected cost							40,000,000
Consumer and Professional Products | Employee Severance and Facility Closing
Restructuring Cost and Reserve [Line Items]
Cash charges						$ 8,977,000
Consumer and Professional Products | Personnel Related Costs
Restructuring Cost and Reserve [Line Items]
Cash charges						5,620,000
Consumer and Professional Products | Facilities, Exit Costs and Other
Restructuring Cost and Reserve [Line Items]
Cash charges						$ 3,357,000
Consumer and Professional Products | Asset Write-Downs
Restructuring Cost and Reserve [Line Items]
Restructuring and related cost, expected cost							$ 19,000,000
Consumer and Professional Products | Subsequent Event
Restructuring Cost and Reserve [Line Items]
Project roll-out term	5 years
Consumer and Professional Products | Subsequent Event | One Time Charges
Restructuring Cost and Reserve [Line Items]
Restructuring and related cost, expected cost	$ 65,000,000
Consumer and Professional Products | Subsequent Event | Capital Investments
Restructuring Cost and Reserve [Line Items]
Restructuring and related cost, expected cost	65,000,000
Consumer and Professional Products | Subsequent Event | Employee Severance and Facility Closing
Restructuring Cost and Reserve [Line Items]
Cash charges	46,000,000
Consumer and Professional Products | Subsequent Event | Personnel Related Costs
Restructuring Cost and Reserve [Line Items]
Cash charges	26,000,000
Consumer and Professional Products | Subsequent Event | Facilities, Exit Costs and Other
Restructuring Cost and Reserve [Line Items]
Cash charges	$ 20,000,000

RESTRUCTURING CHARGES - Summary

RESTRUCTURING CHARGES - Summary of the restructuring and other related charges (Details) $ in Thousands	12 Months Ended
	Sep. 30, 2020USD ($)
Restructuring Cost and Reserve [Line Items]
Charges	$ 15,789
Personnel Related Costs
Restructuring Cost and Reserve [Line Items]
Charges	7,740
Facilities, Exit Costs and Other
Restructuring Cost and Reserve [Line Items]
Charges	3,357
Non-cash facility and other
Restructuring Cost and Reserve [Line Items]
Charges	4,692
Cost of Sales
Restructuring Cost and Reserve [Line Items]
Charges	4,159
Selling, General and Administrative Expenses
Restructuring Cost and Reserve [Line Items]
Charges	$ 11,630

RESTRUCTURING CHARGES - Summa_2

RESTRUCTURING CHARGES - Summary of accrued liability for the restructuring and related charges (Details) $ in Thousands	12 Months Ended
	Sep. 30, 2020USD ($)
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning balance	$ 0
Charges	15,789
Payments	(8,132)
Non-cash charges	(4,692)
Restructuring reserve, ending balance	2,965
Personnel Related Costs
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning balance	0
Charges	7,740
Payments	(5,039)
Non-cash charges	0
Restructuring reserve, ending balance	2,701
Facilities & Exit Costs
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning balance	0
Charges	3,357
Payments	(3,093)
Non-cash charges	0
Restructuring reserve, ending balance	264
Non Cash Facility and Other Costs
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning balance	0
Charges	4,692
Payments	0
Non-cash charges	(4,692)
Restructuring reserve, ending balance	$ 0

WARRANTY LIABILITY (Details)

WARRANTY LIABILITY (Details)	12 Months Ended
	Sep. 30, 2020
Defense Electronics | Minimum
Product Warranty Liability [Line Items]
Product warranty period	1 year
Defense Electronics | Maximum
Product Warranty Liability [Line Items]
Product warranty period	2 years
Home and Building Products (HBP) | Minimum
Product Warranty Liability [Line Items]
Product warranty period	1 year
Home and Building Products (HBP) | Maximum
Product Warranty Liability [Line Items]
Product warranty period	10 years
Consumer and Professional Products
Product Warranty Liability [Line Items]
Product warranty period	90 days
Consumer and Professional Products | Minimum
Product Warranty Liability [Line Items]
Product warranty period	1 year
Consumer and Professional Products | Maximum
Product Warranty Liability [Line Items]
Product warranty period	10 years

WARRANTY LIABILITY (Details) -

WARRANTY LIABILITY (Details) - Summary of changes in warrant liability included in Accrued liabilities - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Movement in Standard Product Warranty Accrual [Roll Forward]
Balance, beginning of period	$ 7,894	$ 8,174
Warranties issued and changes in estimated pre-existing warranties	20,474	16,938
Actual warranty costs incurred	(17,525)	(17,218)
Balance, end of period	$ 10,843	$ 7,894

LONG-TERM DEBT (Details)

LONG-TERM DEBT (Details) $ in Thousands	Jun. 30, 2017USD ($)	Jul. 31, 2016AUD ($)	Jul. 31, 2018GBP (£)	Jul. 31, 2016AUD ($)	Nov. 30, 2012CAD ($)	Jun. 30, 2020USD ($)	Mar. 31, 2020USD ($)	Sep. 30, 2020AUD ($)option	Sep. 30, 2020USD ($)option	Sep. 30, 2019USD ($)	Sep. 30, 2018USD ($)	Sep. 30, 2020GBP (£)	Sep. 30, 2020AUD ($)	Sep. 30, 2020USD ($)	Sep. 30, 2020CAD ($)	Sep. 29, 2020AUD ($)	Jun. 22, 2020USD ($)	Feb. 19, 2020USD ($)	Jan. 30, 2020USD ($)	Jan. 29, 2020USD ($)	Sep. 30, 2019AUD ($)	Sep. 30, 2019USD ($)	Mar. 31, 2016USD ($)property	Sep. 30, 2015USD ($)	Feb. 27, 2014
Debt Instrument [Line Items]
Minimum payments under debt agreements for 2021														$ 9,922,000
Minimum payments under debt agreements for 2022														12,667,000
Minimum payments under debt engagement for 2023														16,124,000
Minimum payments under debt agreements for 2024														1,730,000
Minimum payments under debt agreements for 2025														14,628,000
Minimum payments under debt agreements thereafter														1,009,351,000
Long-term debt, gross														1,064,422,000								$ 1,114,131,000
Capitalized fees & expenses														17,821,000								10,724,000
Gain (loss) from debt extinguishment						$ (969,000)	$ (5,245,000)		$ (7,925,000)	$ 0	$ 0
Line of credit facility, amount outstanding															$ 0
Debt instrument, basis spread on variable rate					1.30%
Outstanding debt														1,046,964,000								1,104,274,000
Revolver Due 2025
Debt Instrument [Line Items]
Line of credit facility, remaining borrowing capacity														370,275,000
Maximum borrowing capacity																			$ 400,000,000	$ 350,000,000
Term Loan | Northcote Holdings Pty. Ltd
Debt Instrument [Line Items]
Debt instrument, face amount		$ 29,625,000		$ 29,625,000
Line of credit facility, amount outstanding													$ 15,875,000	$ 11,287,000		$ 18,375,000					$ 23,375,000
Debt instrument, periodic payment, principal				1,250,000
Debt instrument, balloon payment		9,625,000		9,625,000
Debt instrument, interest rate at period end												2.09%	2.09%	2.09%	2.09%
Term loan balance increase								$ 5,000,000
Term Loan | Ames UK
Debt Instrument [Line Items]
Debt instrument, face amount | £			£ 14,000,000
Debt instrument, periodic payment, principal | £			438,000
Debt instrument, balloon payment | £			7,088,000
Revolving Credit Facility | Northcote Holdings Pty. Ltd
Debt Instrument [Line Items]
Line of credit facility, interest rate at period end												2.04%	2.04%	2.04%	2.04%
Maximum borrowing capacity		20,000,000		20,000,000
Revolving Credit Facility | Ames UK
Debt Instrument [Line Items]
Debt instrument, face amount | £			£ 5,000,000
Debt instrument, basis spread on variable rate			1.50%					1.85%	1.85%
Outstanding debt | £												£ 0
Term and Mortgage Loan July 2018 | Ames UK
Debt Instrument [Line Items]
Outstanding debt												£ 15,398,000		$ 19,799,000
Letter of Credit Subfacility | Revolver Due 2025
Debt Instrument [Line Items]
Line of credit facility, current borrowing capacity																			100,000,000	50,000,000
Line of credit facility, amount outstanding														$ 16,867,000
Multicurrency Subfacility | Revolver Due 2025
Debt Instrument [Line Items]
Line of credit facility, current borrowing capacity																			100,000,000
Margin Rate | Revolver Due 2025
Debt Instrument [Line Items]
Line of credit facility, interest rate during period								0.75%	0.75%
LIBOR Rate
Debt Instrument [Line Items]
Line of credit facility, interest rate during period								1.75%	1.75%
Receivables Purchase Facility | Northcote Holdings Pty. Ltd
Debt Instrument [Line Items]
Debt instrument, face amount		$ 10,000,000		$ 10,000,000
Debt instrument, basis spread on variable rate				1.35%
Outstanding debt													$ 15,000,000								$ 10,000,000
Debt instrument, interest rate at period end												1.49%	1.49%	1.49%	1.49%
Increase in the commitment of receivables purchase line								$ 5,000,000
Finance Lease - Real Estate
Debt Instrument [Line Items]
Long-term debt, gross														$ 17,218,000
Capitalized fees & expenses														30,000
Outstanding debt														17,188,000
Revolver Due 2025
Debt Instrument [Line Items]
Long-term debt, gross														12,858,000
Capitalized fees & expenses														2,209,000
Line of credit facility, current borrowing capacity																			$ 400,000,000	$ 350,000,000
Maximum percentage of equity interest of subsidiaries borrowings guaranteed								65.00%	65.00%
Outstanding debt														10,649,000
Senior Notes | Fair Value, Inputs, Level 1
Debt Instrument [Line Items]
Notes payable, fair value disclosure														1,040,000,000
Senior Notes | Senior Notes Due 2028
Debt Instrument [Line Items]
Debt instrument, face amount																	$ 150,000,000	$ 850,000,000
Stated percentage																	5.75%	5.75%
Issuance price, percentage																	100.25%
Capitalized fees & expenses														16,448,000
Unamortized debt issuance expense														$ 15,376,000
Senior Notes | Senior Notes Due 2022
Debt Instrument [Line Items]
Debt instrument, face amount																	$ 1,000,000,000
Stated percentage												5.25%	5.25%	5.25%	5.25%		5.25%								5.25%
Gain (loss) from debt extinguishment									$ (7,925,000)
Extinguishment of debt, amount									1,000,000,000
Write off of deferred debt issuance cost									6,725,000
Tender offer net premium expense									607,000
Redemption interest expense									$ 593,000
Real Estate Mortgages
Debt Instrument [Line Items]
Debt instrument, face amount																							$ 8,000,000	$ 32,280,000
Number of secured properties | property																							4
Debt instrument, basis spread on variable rate								1.50%	1.50%
ESOP Loans
Debt Instrument [Line Items]
Debt instrument, periodic payment, principal	$ 569,000								$ 635,000
Outstanding debt														$ 29,878,000
Non U.S. Lines of Credit
Debt Instrument [Line Items]
Long-term debt, gross														0								17,576,000
Capitalized fees & expenses														30,000								45,000
Line of credit facility, remaining borrowing capacity														11,210,000	$ 15,000
Outstanding debt														$ (30,000)								$ 17,531,000
Proceeds from long-term lines of credit					$ 15,000				$ 11,210,000
Non U.S. Lines of Credit | LIBOR Rate
Debt Instrument [Line Items]
Line of credit facility, interest rate at period end												1.44%	1.44%	1.44%	1.44%
Non U.S. Lines of Credit | Bankers Acceptance Rate
Debt Instrument [Line Items]
Line of credit facility, interest rate at period end												1.55%	1.55%	1.55%	1.55%
Mortgages | Ames UK
Debt Instrument [Line Items]
Debt instrument, face amount | £			£ 4,000,000
Debt instrument, periodic payment, principal | £			105,000
Debt instrument, balloon payment | £			£ 2,349,000
London Interbank Offered Rate (LIBOR) | Term Loan | Ames UK
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate			2.25%					2.30%	2.30%
London Interbank Offered Rate (LIBOR) | ESOP Loans
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	3.00%							2.91%	2.91%
London Interbank Offered Rate (LIBOR) | Mortgages | Ames UK
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate			1.80%					1.85%	1.85%
Bank Bill Swap Bid Rate | Term Loan | Northcote Holdings Pty. Ltd
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate		1.95%
Bank Bill Swap Bid Rate | Revolving Credit Facility | Northcote Holdings Pty. Ltd
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate				1.90%
Troy, Ohio | Finance Lease - Real Estate
Debt Instrument [Line Items]
Long-term debt, percentage bearing fixed interest, percentage rate												5.00%	5.00%	5.00%	5.00%
Ocala, Florida
Debt Instrument [Line Items]
Finance lease, renewal term												5 years	5 years	5 years	5 years
Ocala, Florida | Finance Lease - Real Estate
Debt Instrument [Line Items]
Long-term debt, percentage bearing fixed interest, percentage rate												5.60%	5.60%	5.60%	5.60%
Number of option to extend | option								2	2

LONG-TERM DEBT (Details) - Summ

LONG-TERM DEBT (Details) - Summary of long-term debt - USD ($) $ in Thousands	Sep. 30, 2020	Sep. 30, 2019
Debt Instrument [Line Items]
Outstanding Balance	$ 1,064,422	$ 1,114,131
less: Current portion	(9,922)	(10,525)
Long-term debt	1,054,500	1,103,606
Original Issuer Premium	363	867
less: Current portion	0	0
Non-current	363	867
Capitalized fees & expenses	(17,821)	(10,724)
Capitalized Fees & Expenses, Current	0	0
Capitalized Fees & Expenses, Noncurrent	(17,821)	(10,724)
Balance Sheet	1,046,964	1,104,274
less: Current portion	(9,922)	(10,525)
Long-term debt	1,037,042	1,093,749
Senior Notes Due 2028
Debt Instrument [Line Items]
Outstanding Balance	1,000,000
Original Issuer Premium	363
Capitalized fees & expenses	(15,376)
Balance Sheet	$ 984,987
Coupon Interest Rate	5.75%
Senior Notes Due 2022
Debt Instrument [Line Items]
Outstanding Balance		1,000,000
Original Issuer Premium		867
Capitalized fees & expenses		(9,175)
Balance Sheet		$ 991,692
Coupon Interest Rate		5.25%
Revolver Due 2025
Debt Instrument [Line Items]
Outstanding Balance	$ 12,858
Original Issuer Premium	0
Capitalized fees & expenses	(2,209)
Balance Sheet	10,649
Revolver Due 2021
Debt Instrument [Line Items]
Outstanding Balance		$ 50,000
Original Issuer Premium		0
Capitalized fees & expenses		(1,243)
Balance Sheet		48,757
Finance Lease - Real Estate
Debt Instrument [Line Items]
Outstanding Balance	17,218
Original Issuer Premium	0
Capitalized fees & expenses	(30)
Balance Sheet	17,188
Finance Lease - Real Estate
Debt Instrument [Line Items]
Outstanding Balance		4,388
Original Issuer Premium		0
Capitalized fees & expenses		(55)
Balance Sheet		$ 4,333
Coupon Interest Rate		5.00%
Non U.S. Lines of Credit
Debt Instrument [Line Items]
Outstanding Balance	0	$ 17,576
Original Issuer Premium	0	0
Capitalized fees & expenses	(30)	(45)
Balance Sheet	(30)	17,531
Non U.S. Term Loans
Debt Instrument [Line Items]
Outstanding Balance	31,086	36,977
Original Issuer Premium	0	0
Capitalized fees & expenses	(160)	(188)
Balance Sheet	30,926	36,789
Other Long Term Debt
Debt Instrument [Line Items]
Outstanding Balance	3,260	5,190
Original Issuer Premium	0	0
Capitalized fees & expenses	(16)	(18)
Balance Sheet	$ 3,244	$ 5,172

LONG-TERM DEBT (Details) - Su_2

LONG-TERM DEBT (Details) - Summary of interest expense incurred - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Debt Instrument [Line Items]
Cash Interest	$ 62,883	$ 62,673	$ 60,349
Amort. Debt Premium	122	270	270
Amort. Deferred Cost & Other Fees	3,539	5,123	4,949
Capitalized interest	128	385	549
Total Interest Expense	$ 66,544	$ 68,066	$ 65,568
Senior Notes Due 2028
Debt Instrument [Line Items]
Effective Interest Rate	5.90%
Cash Interest	$ 32,511
Amort. Debt Premium	0
Amort. Deferred Cost & Other Fees	1,072
Total Interest Expense	$ 33,583
Senior Notes Due 2022
Debt Instrument [Line Items]
Effective Interest Rate	5.67%	5.66%	5.66%
Cash Interest	$ 22,816	$ 52,500	$ 52,500
Amort. Debt Premium	122	270	270
Amort. Deferred Cost & Other Fees	1,735	3,803	3,803
Total Interest Expense	24,673	56,573	56,573
Revolver Due 2025
Debt Instrument [Line Items]
Cash Interest	5,866	6,998	3,718
Amort. Debt Premium	0	0	0
Amort. Deferred Cost & Other Fees	635	980	565
Total Interest Expense	6,501	$ 7,978	$ 4,283
Real Estate Mortgages
Debt Instrument [Line Items]
Effective Interest Rate			6.30%
Cash Interest			$ 1,802
Amort. Debt Premium			0
Amort. Deferred Cost & Other Fees			124
Total Interest Expense			$ 1,926
ESOP Loans
Debt Instrument [Line Items]
Effective Interest Rate		6.30%	3.30%
Cash Interest		$ 937	$ 349
Amort. Debt Premium		0	0
Amort. Deferred Cost & Other Fees		186	320
Total Interest Expense		1,123	669
Finance Lease - Real Estate
Debt Instrument [Line Items]
Cash Interest	386
Amort. Debt Premium	0
Amort. Deferred Cost & Other Fees	25
Total Interest Expense	411
Finance Lease - Real Estate
Debt Instrument [Line Items]
Cash Interest		372	581
Amort. Debt Premium		0	0
Amort. Deferred Cost & Other Fees		25	25
Total Interest Expense		397	606
Non U.S. Lines of Credit
Debt Instrument [Line Items]
Cash Interest	12	19	34
Amort. Debt Premium	0	0	0
Amort. Deferred Cost & Other Fees	15	15	15
Total Interest Expense	27	34	49
Non U.S. Term Loans
Debt Instrument [Line Items]
Cash Interest	975	1,592	1,420
Amort. Debt Premium	0	0	0
Amort. Deferred Cost & Other Fees	55	109	90
Total Interest Expense	1,030	1,701	1,510
Other Long Term Debt
Debt Instrument [Line Items]
Cash Interest	445	640	494
Amort. Debt Premium	0	0	0
Amort. Deferred Cost & Other Fees	2	5	7
Total Interest Expense	$ 447	$ 645	$ 501

EMPLOYEE BENEFIT PLANS (Details

EMPLOYEE BENEFIT PLANS (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018	Jan. 01, 2020	Jan. 01, 2019
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined contribution plan, employer discretionary contribution amount	$ 11,956	$ 11,788	$ 11,053
Postemployment benefits liability	1,833	1,852
Non-service cost components of net periodic benefit cost (credit)	$ (1,559)	(3,148)	(3,649)
Change in discount rate	10.00%
Tax benefit for amortization of pension cost	$ 878	221	342
Defined benefit plan, actuarial gain (loss)	(6,277)
Service cost	15
Adjusted funding target attainment percent				93.70%
Adjusted funding target attainment percent, threshold					80.00%
Defined benefit plans, estimated future employer contributions in next fiscal year	$ 2,107
Completion period of service	1 year
Maximum compensation of proportion	$ 285
Employee stock ownership plan (ESOP), compensation expense	2,878	2,629	9,532
Special dividend ESOP charges			$ 2,588
Employee stock ownership plan (ESOP), deferred shares, fair value	40,217	47,378
Other Postretirement Benefits Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Accumulated other comprehensive income (loss), pension and other postretirement benefit plans, net of tax	(196)	(146)
Pension and other postretirement benefit expense	46	50
Supplemental Employee Retirement Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Accumulated other comprehensive income (loss), pension and other postretirement benefit plans, net of tax	(6,083)	(4,249)
Defined benefit plan, actuarial gain (loss)	(1,494)	(1,901)
Defined benefit plan, expected future benefit payments, next twelve months	1,891
Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Accumulated other comprehensive income (loss), pension and other postretirement benefit plans, net of tax	(48,716)	(30,565)
Defined benefit plan, actuarial gain (loss)	(11,686)	$ (21,481)
Defined benefit plan, expected future benefit payments, next twelve months	11,006
Defined benefit plan, expected future employer contributions, current fiscal year	$ 2,764

EMPLOYEE BENEFIT PLANS (Detai_2

EMPLOYEE BENEFIT PLANS (Details) - Schedule of net periodic costs - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Amortization of:
Total net periodic (benefits) costs	$ (1,559)	$ (3,148)	$ (3,649)
Supplemental Employee Retirement Plan
Net periodic (benefits) costs:
Interest cost	335	503	544
Expected return on plan assets	0	0	0
Amortization of:
Prior service costs	14	14	14
Actuarial loss	399	258	628
Total net periodic (benefits) costs	748	775	1,186
Pension Plan
Net periodic (benefits) costs:
Interest cost	4,267	5,778	5,084
Expected return on plan assets	(10,343)	(10,331)	(10,736)
Amortization of:
Prior service costs	0	0	0
Actuarial loss	3,769	630	755
Total net periodic (benefits) costs	$ (2,307)	$ (3,923)	$ (4,897)

EMPLOYEE BENEFIT PLANS (Detai_3

EMPLOYEE BENEFIT PLANS (Details) - Weighted-average assumptions used in determining the net periodic benefit costs	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Discount rate	2.92%	4.10%	3.64%
Expected return on assets	7.00%	7.00%	7.25%
Weighted average discount rate	2.30%	2.92%
Supplemental Employee Retirement Plan
Defined Benefit Plan Disclosure [Line Items]
Discount rate	2.64%	3.99%	3.18%
Expected return on assets	0.00%	0.00%	0.00%
Weighted average discount rate	1.69%	2.64%

EMPLOYEE BENEFIT PLANS (Detai_4

EMPLOYEE BENEFIT PLANS (Details) - Plan assets and benefit obligation of the defined benefit plans - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Change in benefit obligation:
Actuarial (gain) loss	$ 6,277
Change in plan assets:
Fair value of plan assets at beginning of fiscal year	145,610
Fair value of plan assets at end of fiscal year	147,145	$ 145,610
Pension Plan
Change in benefit obligation:
Benefit obligation at beginning of fiscal year	177,797	161,328
Interest cost	4,267	5,778	$ 5,084
Benefits paid	(10,747)	(10,790)
Actuarial (gain) loss	11,686	21,481
Benefit obligation at end of fiscal year	183,003	177,797	161,328
Change in plan assets:
Fair value of plan assets at beginning of fiscal year	145,610	150,680
Actual return on plan assets	4,261	2,606
Company contributions	8,021	3,114
Benefits paid	(10,747)	(10,790)
Fair value of plan assets at end of fiscal year	147,145	145,610	150,680
Projected benefit obligation in excess of plan assets	(35,858)	(32,187)
Amounts recognized in the statement of financial position consist of:
Accrued liabilities	0	0
Other liabilities (long-term)	(35,858)	(32,187)
Total Liabilities	(35,858)	(32,187)
Net actuarial losses	61,666	47,663
Prior service cost	0	0
Deferred taxes	(12,950)	(17,098)
Total Accumulated other comprehensive loss, net of tax	48,716	30,565
Net amount recognized at September 30,	12,858	(1,622)
Accumulated benefit obligations	183,003	177,797
Information for plans with accumulated benefit obligations in excess of plan assets:
ABO	183,003	177,797
PBO	183,003	177,797
Fair value of plan assets	147,145	145,610
Supplemental Employee Retirement Plan
Change in benefit obligation:
Benefit obligation at beginning of fiscal year	16,180	15,718
Interest cost	335	503	544
Benefits paid	(1,939)	(1,942)
Actuarial (gain) loss	1,494	1,901
Benefit obligation at end of fiscal year	16,070	16,180	15,718
Change in plan assets:
Fair value of plan assets at beginning of fiscal year	0	0
Actual return on plan assets	0	0
Company contributions	1,939	1,942
Benefits paid	(1,939)	(1,942)
Fair value of plan assets at end of fiscal year	0	0	$ 0
Projected benefit obligation in excess of plan assets	(16,070)	(16,180)
Amounts recognized in the statement of financial position consist of:
Accrued liabilities	(1,891)	(1,906)
Other liabilities (long-term)	(14,179)	(14,279)
Total Liabilities	(16,070)	(16,185)
Net actuarial losses	7,700	6,609
Prior service cost	0	14
Deferred taxes	(1,617)	(2,374)
Total Accumulated other comprehensive loss, net of tax	6,083	4,249
Net amount recognized at September 30,	(9,987)	(11,936)
Accumulated benefit obligations	16,070	16,180
Information for plans with accumulated benefit obligations in excess of plan assets:
ABO	16,070	16,180
PBO	16,070	16,180
Fair value of plan assets	$ 0	$ 0

EMPLOYEE BENEFIT PLANS (Detai_5

EMPLOYEE BENEFIT PLANS (Details) - Schedule of weighted average assumptions used in determining benefit obligations	Sep. 30, 2020	Sep. 30, 2019
Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Weighted average discount rate	2.30%	2.92%
Supplemental Employee Retirement Plan
Defined Benefit Plan Disclosure [Line Items]
Weighted average discount rate	1.69%	2.64%

EMPLOYEE BENEFIT PLANS (Detai_6

EMPLOYEE BENEFIT PLANS (Details) - Estimated future benefit payments to retirees $ in Thousands	Sep. 30, 2020USD ($)
Pension Plan
Defined Benefit Plan Disclosure [Line Items]
2021	$ 11,006
2022	10,964
2023	10,945
2024	10,892
2025	10,809
2026 through 2030	52,390
Supplemental Employee Retirement Plan
Defined Benefit Plan Disclosure [Line Items]
2021	1,891
2022	1,787
2023	1,679
2024	1,556
2025	1,437
2026 through 2030	$ 5,354

EMPLOYEE BENEFIT PLANS (Detai_7

EMPLOYEE BENEFIT PLANS (Details) - Actual and weighted-average assets allocation for qualified benefit plans	Sep. 30, 2020	Sep. 30, 2019
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, total actual weighted average plan asset allocations	100.00%	100.00%
Target plan asset allocations	100.00%
Cash and equivalents
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, total actual weighted average plan asset allocations	0.40%	1.90%
Target plan asset allocations	0.00%
Equity securities
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, total actual weighted average plan asset allocations	48.50%	49.90%
Target plan asset allocations	63.00%
Fixed Income Funds
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, total actual weighted average plan asset allocations	31.90%	29.40%
Target plan asset allocations	37.00%
Other Asset Categories
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, total actual weighted average plan asset allocations	19.20%	18.80%
Target plan asset allocations	0.00%

EMPLOYEE BENEFIT PLANS EMPLOYEE

EMPLOYEE BENEFIT PLANS EMPLOYEE BENEFIT PLANS (Details) - Significant unobservable inputs - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Defined Benefit Plan, Change in Fair Value of Plan Assets, Level 3 Reconciliation [Roll Forward]
Fair value of plan assets at beginning of fiscal year	$ 145,610
Fair value of plan assets at end of fiscal year	147,145	$ 145,610
Fair Value, Inputs, Level 3
Defined Benefit Plan, Change in Fair Value of Plan Assets, Level 3 Reconciliation [Roll Forward]
Fair value of plan assets at beginning of fiscal year	8,776	0
Purchases, issuances and settlements	0	7,695
Gains and losses	586	1,081
Fair value of plan assets at end of fiscal year	$ 9,362	$ 8,776

EMPLOYEE BENEFIT PLANS (Detai_8

EMPLOYEE BENEFIT PLANS (Details) - Pension and post-retirement plan assets by asset category - USD ($) $ in Thousands	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, fair value of plan assets	$ 147,145	$ 145,610
Defined benefit plan, fair value of plan assets, subtotal excluding accrued income and plan receivables	142,179	145,319
Fair Value, Inputs, Level 1
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, fair value of plan assets, subtotal excluding accrued income and plan receivables	105,929	105,700
Fair Value, Inputs, Level 2
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, fair value of plan assets, subtotal excluding accrued income and plan receivables	26,888	30,843
Fair Value, Inputs, Level 3
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, fair value of plan assets	9,362	8,776	$ 0
Defined benefit plan, fair value of plan assets, subtotal excluding accrued income and plan receivables	9,362	8,776
Cash and equivalents
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, fair value of plan assets	600	2,791
Cash and equivalents | Fair Value, Inputs, Level 1
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, fair value of plan assets	600	2,791
Cash and equivalents | Fair Value, Inputs, Level 2
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, fair value of plan assets	0	0
Cash and equivalents | Fair Value, Inputs, Level 3
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, fair value of plan assets	0	0
Government agency securities
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, fair value of plan assets	39,811	37,416
Government agency securities | Fair Value, Inputs, Level 1
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, fair value of plan assets	33,675	28,297
Government agency securities | Fair Value, Inputs, Level 2
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, fair value of plan assets	6,136	9,119
Government agency securities | Fair Value, Inputs, Level 3
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, fair value of plan assets	0	0
Debt instruments
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, fair value of plan assets	2,901	3,178
Debt instruments | Fair Value, Inputs, Level 1
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, fair value of plan assets	179	182
Debt instruments | Fair Value, Inputs, Level 2
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, fair value of plan assets	2,722	2,996
Debt instruments | Fair Value, Inputs, Level 3
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, fair value of plan assets	0	0
Equity securities
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, fair value of plan assets	68,987	72,517
Equity securities | Fair Value, Inputs, Level 1
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, fair value of plan assets	68,987	72,517
Equity securities | Fair Value, Inputs, Level 2
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, fair value of plan assets	0	0
Equity securities | Fair Value, Inputs, Level 3
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, fair value of plan assets	0	0
Commingled funds
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, fair value of plan assets	9,362	8,776
Commingled funds | Fair Value, Inputs, Level 1
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, fair value of plan assets	0	0
Commingled funds | Fair Value, Inputs, Level 2
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, fair value of plan assets	0	0
Commingled funds | Fair Value, Inputs, Level 3
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, fair value of plan assets	9,362	8,776
Limited partnerships and hedge fund investments
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, fair value of plan assets	17,867	18,569
Limited partnerships and hedge fund investments | Fair Value, Inputs, Level 1
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, fair value of plan assets	0	0
Limited partnerships and hedge fund investments | Fair Value, Inputs, Level 2
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, fair value of plan assets	17,867	18,569
Limited partnerships and hedge fund investments | Fair Value, Inputs, Level 3
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, fair value of plan assets	0	0
Other Securities
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, fair value of plan assets	2,651	2,072
Other Securities | Fair Value, Inputs, Level 1
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, fair value of plan assets	2,488	1,913
Other Securities | Fair Value, Inputs, Level 2
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, fair value of plan assets	163	159
Other Securities | Fair Value, Inputs, Level 3
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, fair value of plan assets	0	0
Accrued income and plan receivables
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, fair value of plan assets	$ 4,966	$ 291

EMPLOYEE BENEFIT PLANS (Detai_9

EMPLOYEE BENEFIT PLANS (Details) - ESOP Shares - shares	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Retirement Benefits [Abstract]
Allocated shares	3,301,448	3,209,069
Unallocated shares	2,058,187	2,259,308	2,477,000
Employee stock ownership plan (ESOP), shares in ESOP	5,359,635	5,468,377

INCOME TAXES (Details) - Compon

INCOME TAXES (Details) - Components of Income before taxes and discontinued operations - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Income Tax Disclosure [Abstract]
Domestic	$ 42,634	$ 49,723	$ 4,942
Non-U.S.	40,123	22,455	28,868
Income (loss) before taxes from continuing operations	$ 82,757	$ 72,178	$ 33,810

INCOME TAXES (Details) - Provis

INCOME TAXES (Details) - Provision (benefit) for income taxes on income from continuing operations - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Income Tax Disclosure [Abstract]
Current	$ 27,233	$ 28,778	$ 18,188
Deferred	2,095	(2,222)	(17,633)
Total	29,328	26,556	555
U.S. Federal	10,978	14,160	(12,714)
State and local	7,331	6,187	5,175
Non-U.S.	$ 11,019	$ 6,209	$ 8,094

INCOME TAXES (Details)

INCOME TAXES (Details) - USD ($)	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Income Tax Examination [Line Items]
U.S. Federal income tax provision (benefit) rate	21.00%	21.00%	24.50%
Provisional transition tax charge			$ (20,587,000)
Transition tax charge under TCJA			12,699,000
Transition tax charge under TCJA, remaining amount	$ 8,344,000
Deferred tax assets, lease obligations	43,045,000
Deferred tax liabilities, leasing arrangements	(41,747,000)
Valuation allowance increase (decrease)	(999,000)
Undistributed earnings of foreign subsidiaries	100,102,000
Deferred tax assets, valuation allowance	9,824,000	$ 10,823,000
Potential tax benefits impact on effective tax rate	909,000
Liability for uncertainty in income taxes, current	77,000	66,000
Domestic Tax Authority
Income Tax Examination [Line Items]
Operating loss carryforwards	0	5,419,000
Interest loss carryforwards	0	25,000,000
Tax credit carryforward amount	5,954,000	8,948,000
Domestic Tax Authority | Capital Loss Carryforward
Income Tax Examination [Line Items]
Tax credit carryforward amount	10,500,000	9,524,000
Non-U.S. Tax Authority
Income Tax Examination [Line Items]
Operating loss carryforwards	9,671,000	7,413,000
State and Local Jurisdiction
Income Tax Examination [Line Items]
Operating loss carryforwards	$ 124,191,000	$ 127,354,000
Previously Reported
Income Tax Examination [Line Items]
Transition tax charge under TCJA			$ 13,100,000

INCOME TAXES (Details) - Schedu

INCOME TAXES (Details) - Schedule of effective income tax rate reconciliation	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Income Tax Disclosure [Abstract]
U.S. Federal income tax provision (benefit) rate	21.00%	21.00%	24.50%
State and local taxes, net of Federal benefit	6.00%	6.60%	10.20%
Non-U.S. taxes - foreign permanent items and taxes	3.30%	2.00%	3.60%
Change in tax contingency reserves	0.10%	(0.70%)	(0.60%)
Impact of federal rate change on deferred tax balances	0.00%	0.00%	(60.00%)
Tax Reform-Repatriation of Foreign Earnings and GILTI	0.00%	1.00%	61.60%
Change in valuation allowance	(1.50%)	3.30%	13.40%
Other non-deductible/non-taxable items, net	0.014	0.031	(0.052)
Non-deductible officer's compensation	4.40%	5.20%	6.40%
Research and U.S. foreign tax credits	1.40%	(4.70%)	(39.40%)
Share based compensation	0.00%	0.40%	(3.80%)
Other	(0.70%)	(0.40%)	(9.10%)
Effective tax provision (benefit) rate	35.40%	36.80%	1.60%

INCOME TAXES (Details) - Sche_2

INCOME TAXES (Details) - Schedule of deferred tax assets and liabilities - USD ($) $ in Thousands	Sep. 30, 2020	Sep. 30, 2019
Deferred tax assets:
Bad debt reserves	$ 3,980	$ 1,980
Inventory reserves	9,371	8,361
Deferred compensation (equity compensation and defined benefit plans)	18,904	16,544
Compensation benefits	5,499	5,186
Insurance reserve	1,918	1,873
Warranty reserve	3,981	2,896
Lease liabilities	43,045
Net operating loss	9,618	11,077
Tax credits	7,031	9,373
Capital loss carryback	2,205	2,000
Interest	0	5,250
Other reserves and accruals	6,094	3,738
Deferred tax assets, gross	111,646	68,278
Valuation allowance	(9,824)	(10,823)
Total deferred tax assets	101,822	57,455
Deferred tax liabilities:
Goodwill and intangibles	(44,051)	(42,477)
Property, plant and equipment	(48,172)	(43,996)
Right-of-use assets	(41,747)
Other	(634)	(1,096)
Total deferred tax liabilities	(134,604)	(87,569)
Net deferred tax liabilities	$ (32,782)	$ (30,114)

INCOME TAXES (Details) - Comp_2

INCOME TAXES (Details) - Components of net deferred tax asset (liability), by balance sheet account - USD ($) $ in Thousands	Sep. 30, 2020	Sep. 30, 2019
Income Tax Contingency [Line Items]
Net deferred liability	$ (32,782)	$ (30,114)
Other assets
Income Tax Contingency [Line Items]
Net deferred liability	614	137
Other liabilities
Income Tax Contingency [Line Items]
Net deferred liability	(34,008)	(31,141)
Liabilities of discontinued operations
Income Tax Contingency [Line Items]
Net deferred liability	$ 612	$ 890

INCOME TAXES (Details) - Sche_3

INCOME TAXES (Details) - Schedule of unrecognized tax benefits - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Beginning balance	$ 4,061	$ 4,519
Additions based on tax positions related to the current year	125	117
Additions based on tax positions related to prior years	20
Reductions based on tax positions related to prior years	(3)	(559)
Lapse of Statutes	(23)	(16)
Ending balance	$ 4,180	$ 4,061

STOCKHOLDERS' EQUITY AND EQUI_3

STOCKHOLDERS' EQUITY AND EQUITY COMPENSATION (Details)

Aug. 21, 2020USD ($)$ / sharesshares

Aug. 21, 2020USD ($)$ / sharesshares

Aug. 18, 2020USD ($)$ / sharesshares

Apr. 16, 2018USD ($)

Mar. 07, 2018USD ($)$ / shares

Jan. 29, 2016shares

Aug. 31, 2020USD ($)$ / sharesshares

Sep. 30, 2020USD ($)senior_executive$ / sharesshares

Sep. 30, 2019USD ($)$ / shares

Sep. 30, 2018USD ($)$ / shares

Nov. 12, 2020$ / shares

Jan. 30, 2020shares

Aug. 01, 2018USD ($)

Jun. 19, 2018shares

Jan. 31, 2018shares

Aug. 03, 2016USD ($)

Dec. 31, 2008shares

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Common stock, dividends, per share, cash paid (in dollars per share) | $ / shares

$ 0.30

$ 0.29

$ 0.28

Accrued dividends | $

$ 3,535,000

Sale of stock, number of shares issued (in shares)

700,000

8,700,000

8,000,000

8,700,000

Sale of stock, stock price (in dollars per share) | $ / shares

$ 21.50

$ 21.50

$ 21.50

$ 21.50

Net process from sale of stock | $

$ 14,335,000

$ 178,165,000

$ 163,830,000

$ 178,165,000

Share-based payment award, number of shares authorized (in shares)

4,852,762

Share-based payment award, expiration period

10 years

Maximum percentage of exercise price at grant date fair value

100.00%

Share-based payment award, options, vested in period, fair value | $

$ 17,889,000

$ 4,748,000

$ 11,216,000

Employee service share-based compensation, nonvested awards, compensation not yet recognized, share-based awards other than options | $

$ 22,340,000

Employee service share-based compensation, nonvested awards, compensation cost not yet recognized, period for recognition

2 years 3 months 18 days

Stock repurchase program, authorized amount | $

$ 50,000,000

$ 50,000,000

Stock repurchased during period (in shares)

0

Stock repurchase program, remaining authorized repurchase amount | $

$ 57,955,000

Shares paid for tax withholding for share based compensation (in shares)

340,775

Shares paid for tax withholding for share based compensation, value | $

$ 7,409,000

Shares paid for tax withholding for share based compensation, value per share (in dollars per share) | $ / shares

$ 21.74

Common stock, number of shares held by shareholder

5,583,375

GS Direct

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Investment owned, balance (in shares)

10,000,000

Incentive Plan

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Share-based payment award, number of shares authorized (in shares)

5,050,000

Incentive Stock Options

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Stock issued during period, shares, new issues (in shares)

600,000

Share-based payment award, number of shares available for grant (in shares)

1,167,172

Restricted Stock

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Instruments grants in period (in shares)

1,061,624

Weighted average grant date fair value (in dollars per share) | $ / shares

$ 17.10

Instruments vested in period (in shares)

831,748

Shares paid for tax withholding for share based compensation (in shares)

3,307

Shares paid for tax withholding for share based compensation, value | $

$ 70,000

Shares paid for tax withholding for share based compensation, value per share (in dollars per share) | $ / shares

$ 21.22

Restricted Stock | Minimum

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Share-based payment award, award vesting period

3 years

Restricted Stock | Maximum

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Share-based payment award, award vesting period

4 years

Performance Shares

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Share-based payment award, award vesting period

3 years

Instruments grants in period (in shares)

1,061,624

Instruments vested in period, fair value | $

$ 7,446,000

Weighted average grant date fair value (in dollars per share) | $ / shares

$ 21.38

Restricted Stock and Performance Shares

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Instruments grants in period (in shares)

348,280

Director

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Share-based payment award, award vesting period

3 years

Instruments grants in period (in shares)

53,344

Instruments vested in period, fair value | $

$ 1,170,000

Weighted average grant date fair value (in dollars per share) | $ / shares

$ 21.93

Executive Officer | Restricted Stock

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Share-based payment award, award vesting period

4 years

Instruments number of persons granted shares (in shares) | senior_executive

2

Post-vesting holding period

2 years

Executive Officer | Restricted Stock | Minimum

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Instruments vested in period (in shares)

480,000

Executive Officer | Restricted Stock | Maximum

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Instruments vested in period (in shares)

660,000

Executive Officer | Performance Shares

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Weighted average grant date fair value (in dollars per share) | $ / shares

$ 14.45

Equity instruments other than options, granted in period, fair value | $

$ 9,534,000

Executive Officer | Restricted Stock and Performance Shares

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Instruments grants in period (in shares)

660,000

Incentive Plan

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Share-based payment award, number of shares authorized (in shares)

1,700,000

1,000,000

Special Dividends

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Common stock, dividends declared (in dollars per share) | $ / shares

$ 1

Dividends, common stock, cash | $

$ 38,073,000

Payments of dividends | $

$ 38,073,000

Subsequent Event

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Dividends payable, amount per share (in dollars per share) | $ / shares

$ 0.08

STOCKHOLDERS' EQUITY AND EQUI_4

STOCKHOLDERS' EQUITY AND EQUITY COMPENSATION (Details) - Summary of stock-based compensation expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Stockholders' Equity Note [Abstract]
Restricted stock	$ 14,702	$ 13,285	$ 10,078
ESOP	2,878	2,629	9,532
Total stock based compensation	$ 17,580	$ 15,914	$ 19,610

STOCKHOLDERS' EQUITY AND EQUI_5

STOCKHOLDERS' EQUITY AND EQUITY COMPENSATION (Details) - Summary of restricted stock activity	12 Months Ended
	Sep. 30, 2020$ / sharesshares
Shares
Unvested (in shares)	3,420,000
Unvested (in shares)	3,556,000
Restricted Stock
Shares
Unvested (in shares)	3,713,573
Granted (in shares)	1,061,624
Vested (in shares)	(831,748)
Forfeited (in shares)	(257,859)
Unvested (in shares)	3,685,590
Weighted Average Grant- Date Fair Value
Unvested (in dollars per share) | $ / shares	$ 12.96
Granted (in dollars per share) | $ / shares	17.10
Vested (in dollars per share) | $ / shares	21.51
Forfeited (in dollars per share) | $ / shares	15.35
Unvested (in dollars per share) | $ / shares	$ 14.30

COMMITMENTS AND CONTINGENT LI_3

COMMITMENTS AND CONTINGENT LIABILITIES COMMITMENTS AND CONTINGENT LIABILITIES - Aggregate future maturities of lease payments for operating leases (Details) $ in Thousands	Sep. 30, 2020USD ($)
Operating Lease Liabilities:
2021	$ 38,411
2022	33,286
2023	25,599
2024	19,057
2025	16,334
2026	71,903
Total lease payments	204,590
Less: Imputed Interest	(36,688)
Present value of lease liabilities	167,902
Finance Lease Liabilities:
2021	4,282
2022	2,695
2023	2,375
2024	2,119
2025	2,074
2026	9,850
Total lease payments	23,395
Less: Imputed Interest	(4,704)
Present value of lease liabilities	$ 18,691

COMMITMENTS AND CONTINGENT LI_4

COMMITMENTS AND CONTINGENT LIABILITIES (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018	Apr. 30, 2009
Commitments and Contingencies Disclosure [Abstract]
Purchase obligation, purchases during period	$ 239,365	$ 226,026	$ 209,924
Purchase obligation, due in next twelve months	377,388
Purchase obligation due in second year	9,748
Purchase obligation due in third year	12
Purchase obligation due in fourth year	0
Purchase obligation due in fifth year	$ 0
Net capital cost value in proposed remedial action plan				$ 10,000

EARNINGS PER SHARE EARNINGS P_2

EARNINGS PER SHARE EARNINGS PER SHARE (Details) - USD ($) $ / shares in Units, $ in Thousands	Aug. 21, 2020	Aug. 21, 2020	Aug. 18, 2020	Aug. 31, 2020
Earnings Per Share [Abstract]
Sale of stock, number of shares issued (in shares)	700,000	8,700,000	8,000,000	8,700,000
Sale of stock, stock price (in dollars per share)	$ 21.50	$ 21.50	$ 21.50	$ 21.50
Net process from sale of stock	$ 14,335	$ 178,165	$ 163,830	$ 178,165

EARNINGS PER SHARE EARNINGS P_3

EARNINGS PER SHARE EARNINGS PER SHARE (Details) - Basic and diluted EPS from continuing operations - shares	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Earnings Per Share [Abstract]
Common shares outstanding (in shares)	56,130,000	46,806,000	45,675,000
Unallocated ESOP shares (in shares)	(2,058,187)	(2,259,308)	(2,477,000)
Non-vested restricted stock (in shares)	(3,556,000)	(3,420,000)	(2,522,000)
Impact of weighted average shares (in shares)	(7,928,000)	(193,000)	329,000
Weighted average shares outstanding - basic (in shares)	42,588,000	40,934,000	41,005,000
Incremental shares from stock based compensation (in shares)	2,427,000	1,954,000	1,417,000
Weighted average shares outstanding - diluted (in shares)	45,015,000	42,888,000	42,422,000

RELATED PARTIES (Details)

RELATED PARTIES (Details) - USD ($) $ in Thousands	Oct. 02, 2017	Sep. 30, 2020	Jun. 22, 2020	Jun. 19, 2018	Nov. 15, 2017	Feb. 27, 2014
Related Party Transaction [Line Items]
Common stock, number of shares held by shareholder				5,583,375
Discontinued Operations, Held-for-sale | Plastics
Related Party Transaction [Line Items]
Disposal group, including discontinued operation, consideration					$ 465,000
Senior Notes Due 2022 | Senior Notes
Related Party Transaction [Line Items]
Proceeds from issuance of debt	$ 275,000
Stated percentage		5.25%	5.25%			5.25%

QUARTERLY FINANCIAL INFORMATI_3

QUARTERLY FINANCIAL INFORMATION (UNAUDITED) (Details) - USD ($) $ in Thousands	3 Months Ended					12 Months Ended
	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Quarterly Financial Information Disclosure [Abstract]
Restructuring charges	$ 3,488	$ 1,224	$ 3,005	$ 4,148
Acquisition costs			2,321			$ 2,960	$ 0
Gain (loss) from debt extinguishment		$ (969)	$ (5,245)			(7,925)	0	$ 0
Acquisition contingent consideration	(1,403)				$ 1,333	$ 1,733	$ 1,646	$ 0
Tax benefit for acquisition cost	15
Tax expense (benefit) from debt extinguishment	$ (24)

QUARTERLY FINANCIAL INFORMATI_4

QUARTERLY FINANCIAL INFORMATION (UNAUDITED) (Details) - Schedule of quarterly financial information - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Quarterly Financial Information Disclosure [Abstract]
Revenue	$ 660,673	$ 632,061	$ 566,350	$ 548,438	$ 574,164	$ 574,970	$ 549,633	$ 510,522	$ 2,407,522	$ 2,209,289	$ 1,977,918
Gross Profit	174,470	165,003	152,032	149,921	158,458	151,699	133,537	139,780	641,426	583,474	511,318
Income from continuing operations	$ 20,091	$ 21,831	$ 895	$ 10,612	$ 16,251	$ 14,128	$ 6,490	$ 8,753	$ 53,429	$ 45,622	$ 33,255
Per Share - Basic (in usd per share)	$ 0.44	$ 0.52	$ 0.02	$ 0.26	$ 0.40	$ 0.34	$ 0.16	$ 0.21	$ 1.25	$ 1.11	$ 0.81
Per Share - Diluted (in usd per share)	$ 0.41	$ 0.50	$ 0.02	$ 0.24	$ 0.37	$ 0.33	$ 0.15	$ 0.21	$ 1.19	$ 1.06	$ 0.78

REPORTABLE SEGMENTS (Details)

REPORTABLE SEGMENTS (Details) - segment	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Segment Reporting Information [Line Items]
Number of reportable segments	3
Segment Revenue Benchmark | Home Depot | Consumer and Professional Products
Segment Reporting Information [Line Items]
Concentration risk, percentage	27.00%	28.00%	29.00%
Segment Revenue Benchmark | Home Depot | Home and Building Products (HBP)
Segment Reporting Information [Line Items]
Concentration risk, percentage	12.00%	13.00%	16.00%
Segment Revenue Benchmark | United States Government | Defense Electronics
Segment Reporting Information [Line Items]
Concentration risk, percentage	69.00%	63.00%	62.00%
Consolidated Revenue from Continuing Operations Benchmark | Home Depot | Consumer and Professional Products
Segment Reporting Information [Line Items]
Concentration risk, percentage	13.00%	13.00%	14.00%
Consolidated Revenue from Continuing Operations Benchmark | Home Depot | Home and Building Products (HBP)
Segment Reporting Information [Line Items]
Concentration risk, percentage	5.00%	5.00%	6.00%
Consolidated Revenue from Continuing Operations Benchmark | United States Government | Defense Electronics
Segment Reporting Information [Line Items]
Concentration risk, percentage	9.00%	10.00%	10.00%

REPORTABLE SEGMENTS (Details) -

REPORTABLE SEGMENTS (Details) - Schedule of summary of reconciliation of segment profit before taxes and operations - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Segment Reporting Information [Line Items]
Revenue	$ 660,673	$ 632,061	$ 566,350	$ 548,438	$ 574,164	$ 574,970	$ 549,633	$ 510,522	$ 2,407,522	$ 2,209,289	$ 1,977,918
Segment Adjusted EBITDA									282,912	245,942	213,463
Unallocated amounts, excluding depreciation									(47,013)	(46,302)	(45,343)
Adjusted EBITDA									235,899	199,640	168,120
Net interest expense									(65,791)	(67,260)	(63,871)
Depreciation and amortization									(62,409)	(61,848)	(55,803)
Restructuring charges									(15,790)	0	0
Loss from debt extinguishment		$ (969)	$ (5,245)						(7,925)	0	0
Acquisition contingent consideration	$ (1,403)				$ 1,333				1,733	1,646	0
Acquisition costs									(2,960)	0	(7,597)
Special dividend charges											(2,588)
Secondary equity offering costs									0	0	(1,205)
Income before taxes from continuing operations									82,757	72,178	33,810
Capital expenditures									48,998	45,361	50,138
Consumer and Professional Products
Segment Reporting Information [Line Items]
Revenue									1,139,233	1,000,608	953,612
Segment Adjusted EBITDA									104,053	90,677	77,061
Depreciation and amortization									(32,788)	(32,289)	(30,816)
Capital expenditures									23,321	17,828	23,040
Home and Building Products (HBP)
Segment Reporting Information [Line Items]
Revenue									927,313	873,640	697,969
Segment Adjusted EBITDA									153,631	120,161	100,339
Depreciation and amortization									(18,361)	(18,334)	(13,717)
Capital expenditures									17,499	16,498	13,547
Defense Electronics
Segment Reporting Information [Line Items]
Revenue									340,976	335,041	326,337
Segment Adjusted EBITDA									25,228	35,104	36,063
Depreciation and amortization									(10,645)	(10,667)	(10,801)
Capital expenditures									7,830	10,492	10,941
Operating
Segment Reporting Information [Line Items]
Depreciation and amortization									(61,794)	(61,290)	(55,334)
Capital expenditures									48,650	44,818	47,528
Corporate
Segment Reporting Information [Line Items]
Depreciation and amortization									(615)	(558)	(469)
Capital expenditures									348	543	2,610
Continuing Operations
Segment Reporting Information [Line Items]
Special dividend charges									0	0	(3,220)
Postretirement Life Insurance | Continuing Operations
Segment Reporting Information [Line Items]
Cost of life insurance benefit									$ 0	$ 0	$ (2,614)

REPORTABLE SEGMENTS (Details)_2

REPORTABLE SEGMENTS (Details) - Schedule of summary of segment assets - USD ($) $ in Thousands	Sep. 30, 2020	Sep. 30, 2019
Segment Reporting Information [Line Items]
Continuing assets	$ 2,447,520	$ 2,071,730
Assets of discontinued operations	8,497	3,209
Total Assets	2,456,017	2,074,939
Consumer and Professional Products
Segment Reporting Information [Line Items]
Continuing assets	1,262,705	1,070,510
Home and Building Products (HBP)
Segment Reporting Information [Line Items]
Continuing assets	606,785	571,216
Defense Electronics
Segment Reporting Information [Line Items]
Continuing assets	329,128	347,575
Operating
Segment Reporting Information [Line Items]
Continuing assets	2,198,618	1,989,301
Corporate
Segment Reporting Information [Line Items]
Continuing assets	$ 248,902	$ 82,429

REPORTABLE SEGMENTS (Details)_3

REPORTABLE SEGMENTS (Details) - Schedule of disaggregated revenue by segment - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Segment Reporting Information [Line Items]
Revenue	$ 660,673	$ 632,061	$ 566,350	$ 548,438	$ 574,164	$ 574,970	$ 549,633	$ 510,522	$ 2,407,522	$ 2,209,289	$ 1,977,918
Consumer and Professional Products
Segment Reporting Information [Line Items]
Revenue									1,139,233	1,000,608	953,612
Home and Building Products (HBP)
Segment Reporting Information [Line Items]
Revenue									927,313	873,640	697,969
Defense Electronics
Segment Reporting Information [Line Items]
Revenue									340,976	335,041	$ 326,337
Residential Repair and Remodel | Consumer and Professional Products
Segment Reporting Information [Line Items]
Revenue									173,859	140,369
Residential Repair and Remodel | Home and Building Products (HBP)
Segment Reporting Information [Line Items]
Revenue									467,112	439,287
Retail | Consumer and Professional Products
Segment Reporting Information [Line Items]
Revenue									575,947	528,279
Residential New Construction | Consumer and Professional Products
Segment Reporting Information [Line Items]
Revenue									59,907	58,709
Residential New Construction | Home and Building Products (HBP)
Segment Reporting Information [Line Items]
Revenue									105,285	99,014
Industrial | Consumer and Professional Products
Segment Reporting Information [Line Items]
Revenue									40,285	45,129
International Excluding North America | Consumer and Professional Products
Segment Reporting Information [Line Items]
Revenue									289,235	228,122
Commercial Construction | Home and Building Products (HBP)
Segment Reporting Information [Line Items]
Revenue									354,916	335,339
United States Government | Defense Electronics
Segment Reporting Information [Line Items]
Revenue									222,537	211,405
International | Defense Electronics
Segment Reporting Information [Line Items]
Revenue									100,623	105,705
Commercial | Defense Electronics
Segment Reporting Information [Line Items]
Revenue									$ 17,816	$ 17,931

REPORTABLE SEGMENTS REPORTABLE

REPORTABLE SEGMENTS REPORTABLE SEGMENTS (Details) - Schedule of disaggregated revenue by geographic region - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Segment Reporting Information [Line Items]
Revenue	$ 660,673	$ 632,061	$ 566,350	$ 548,438	$ 574,164	$ 574,970	$ 549,633	$ 510,522	$ 2,407,522	$ 2,209,289	$ 1,977,918
Consumer and Professional Products
Segment Reporting Information [Line Items]
Revenue									1,139,233	1,000,608	953,612
Home and Building Products (HBP)
Segment Reporting Information [Line Items]
Revenue									927,313	873,640	697,969
Defense Electronics
Segment Reporting Information [Line Items]
Revenue									340,976	335,041	$ 326,337
United States
Segment Reporting Information [Line Items]
Revenue									1,880,597	1,737,263
United States | Consumer and Professional Products
Segment Reporting Information [Line Items]
Revenue									769,100	690,772
United States | Home and Building Products (HBP)
Segment Reporting Information [Line Items]
Revenue									877,115	820,396
United States | Defense Electronics
Segment Reporting Information [Line Items]
Revenue									234,382	226,095
Europe
Segment Reporting Information [Line Items]
Revenue									123,822	100,308
Europe | Consumer and Professional Products
Segment Reporting Information [Line Items]
Revenue									85,339	63,284
Europe | Home and Building Products (HBP)
Segment Reporting Information [Line Items]
Revenue									130	109
Europe | Defense Electronics
Segment Reporting Information [Line Items]
Revenue									38,353	36,915
Canada
Segment Reporting Information [Line Items]
Revenue									124,777	122,367
Canada | Consumer and Professional Products
Segment Reporting Information [Line Items]
Revenue									74,072	72,327
Canada | Home and Building Products (HBP)
Segment Reporting Information [Line Items]
Revenue									38,662	39,472
Canada | Defense Electronics
Segment Reporting Information [Line Items]
Revenue									12,043	10,568
Australia
Segment Reporting Information [Line Items]
Revenue									204,894	169,019
Australia | Consumer and Professional Products
Segment Reporting Information [Line Items]
Revenue									203,012	165,291
Australia | Home and Building Products (HBP)
Segment Reporting Information [Line Items]
Revenue									0	16
Australia | Defense Electronics
Segment Reporting Information [Line Items]
Revenue									1,882	3,712
Consolidated revenue
Segment Reporting Information [Line Items]
Revenue									73,432	80,332
Consolidated revenue | Consumer and Professional Products
Segment Reporting Information [Line Items]
Revenue									7,710	8,934
Consolidated revenue | Home and Building Products (HBP)
Segment Reporting Information [Line Items]
Revenue									11,406	13,647
Consolidated revenue | Defense Electronics
Segment Reporting Information [Line Items]
Revenue									$ 54,316	$ 57,751

OTHER INCOME (EXPENSE) (Details

OTHER INCOME (EXPENSE) (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Other Income and Expenses [Abstract]
Other income (expense)	$ 1,445	$ 3,127	$ 4,880
Currency exchange gains (losses)	(915)	(438)	(200)
Investment income (loss)	184	(40)	1,184
Net periodic benefit cost (credit)	(1,559)	$ (3,148)	$ (3,649)
Technology recognition award	$ 700

OTHER COMPREHENSIVE INCOME (L_3

OTHER COMPREHENSIVE INCOME (LOSS) (Details) - Summary of other comprehensive income - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Accumulated Other Comprehensive Income (Loss) [Line Items]
Pre-tax	$ (9,344)	$ (39,454)	$ 34,384
Tax	3,168	7,650	(8,015)
Net of tax	(6,176)	(31,804)	26,369
Foreign currency translation adjustments
Accumulated Other Comprehensive Income (Loss) [Line Items]
Pre-tax	5,601	(8,460)	9,403
Tax	0	0	0
Net of tax	5,601	(8,460)	9,403
Pension and other defined benefit plans
Accumulated Other Comprehensive Income (Loss) [Line Items]
Pre-tax	(14,955)	(30,581)	24,081
Tax	3,171	7,526	(7,700)
Net of tax	(11,784)	(23,055)	16,381
Cash flow hedge
Accumulated Other Comprehensive Income (Loss) [Line Items]
Pre-tax	10	(413)	900
Tax	(3)	124	(315)
Net of tax	$ 7	$ (289)	$ 585

OTHER COMPREHENSIVE INCOME (L_4

OTHER COMPREHENSIVE INCOME (LOSS) (Details) - Accumulated other comprehensive income - USD ($) $ in Thousands	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2017
Accumulated Other Comprehensive Income (Loss) [Line Items]
SHAREHOLDERS’ EQUITY	$ 700,151	$ 477,763	$ 474,391	$ 398,808
Foreign currency translation adjustments
Accumulated Other Comprehensive Income (Loss) [Line Items]
SHAREHOLDERS’ EQUITY	(25,683)	(31,284)
Pension and other defined benefit plans
Accumulated Other Comprehensive Income (Loss) [Line Items]
SHAREHOLDERS’ EQUITY	(46,598)	(34,814)
Cash flow hedge
Accumulated Other Comprehensive Income (Loss) [Line Items]
SHAREHOLDERS’ EQUITY	189	182
AOCI attributable to parent
Accumulated Other Comprehensive Income (Loss) [Line Items]
SHAREHOLDERS’ EQUITY	$ (72,092)	$ (65,916)	$ (34,112)	$ (60,481)

OTHER COMPREHENSIVE INCOME (L_5

OTHER COMPREHENSIVE INCOME (LOSS) (Details) - Total comprehensive income (loss) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Other Comprehensive Income (Loss), Net of Tax [Abstract]
Net income	$ 53,429	$ 37,287	$ 125,678
Other comprehensive income (loss), net of taxes	(6,176)	(31,804)	26,369
Comprehensive income	$ 47,253	$ 5,483	$ 152,047

OTHER COMPREHENSIVE INCOME (L_6

OTHER COMPREHENSIVE INCOME (LOSS) (Details) - Summary of amounts reclassified from accumulated other comprehensive income - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income before taxes from continuing operations	$ 82,757	$ 72,178	$ 33,810
Provision (benefit) from income taxes	29,328	26,556	555
Net income	53,429	37,287	125,678
Pension and other defined benefit plans | Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income before taxes from continuing operations	(4,182)	(902)	(1,397)
Cash flow hedges | Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income before taxes from continuing operations	(2,163)	1,361	657
AOCI attributable to parent | Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income before taxes from continuing operations	(6,345)	459	(740)
Provision (benefit) from income taxes	(1,332)	96	(155)
Net income	$ (5,013)	$ 363	$ (585)

LEASES - Narrative (Details)

LEASES - Narrative (Details)	12 Months Ended
	Sep. 30, 2020USD ($)option	Sep. 30, 2019USD ($)	Sep. 30, 2018USD ($)	Oct. 01, 2019USD ($)
Lessee, Lease, Description [Line Items]
ROU assets	$ 161,627,000
Lease liabilities	167,902,000
Impairment charge, operating lease	1,968,000
Impairment charge, leasehold improvements	671,000
Rent expense		$ 37,068,000	$ 35,726,000
Accumulated depreciation	2,383,000
Long-term debt	1,046,964,000	1,104,274,000
Finance lease, net		6,546,000
Depreciation expense		3,967,000	$ 3,514,000
Finance Lease - Real Estate
Lessee, Lease, Description [Line Items]
Long-term debt	$ 17,188,000
Finance Lease - Real Estate
Lessee, Lease, Description [Line Items]
Long-term debt		$ 4,333,000
Troy, Ohio | Finance Lease - Real Estate
Lessee, Lease, Description [Line Items]
Long-term debt, percentage bearing fixed interest, percentage rate	5.00%
Ocala, Florida | Finance Lease - Real Estate
Lessee, Lease, Description [Line Items]
Long-term debt, percentage bearing fixed interest, percentage rate	5.60%
Number of option to extend | option	2
Accounting Standards Update 2016-02
Lessee, Lease, Description [Line Items]
Accounting Standards Update [Extensible List]	us-gaap:AccountingStandardsUpdate201602Member
Cumulative Effect, Period of Adoption, Adjustment
Lessee, Lease, Description [Line Items]
ROU assets				$ 163,552,000
Lease liabilities				$ 163,676,000

LEASES - Schedule of lease cost

LEASES - Schedule of lease cost (Details) $ in Thousands	12 Months Ended
	Sep. 30, 2020USD ($)
Lease Cost
Fixed	$ 38,554
Variable	7,822
Short-term	5,606
Total	$ 51,982

LEASES - Supplemental cash flow

LEASES - Supplemental cash flow information (Details) $ in Thousands	12 Months Ended
	Sep. 30, 2020USD ($)
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	$ 48,141
Financing cash flows from finance leases	4,122
Total	$ 52,263

LEASES - Summary of supplementa

LEASES - Summary of supplemental balance sheet information (Details) $ in Thousands	Sep. 30, 2020USD ($)
Operating Leases:
Operating right-of-use assets	$ 161,627
Lease Liabilities:
Current portion of operating lease liabilities	31,848
Long-term operating lease liabilities	136,054
Total operating lease liabilities	167,902
Finance Leases:
Property, plant and equipment, net	$ 18,774
Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	us-gaap:PropertyPlantAndEquipmentNet
Lease Liabilities:
Notes payable and current portion of long-term debt	$ 3,352
Long-term debt, net	15,339
Total financing lease liabilities	$ 18,691
Finance Lease, Liability, Current, Statement of Financial Position [Extensible List]	us-gaap:LongTermDebtCurrent
Finance Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List]	us-gaap:LongTermDebtNoncurrent
Accumulated depreciation	$ 2,383

LEASES - Summary of future matu

LEASES - Summary of future maturities of lease payments for operating leases (Details) $ in Thousands	Sep. 30, 2020USD ($)
Operating Leases
2021	$ 38,411
2022	33,286
2023	25,599
2024	19,057
2025	16,334
2026	71,903
Total lease payments	204,590
Less: Imputed Interest	(36,688)
Present value of lease liabilities	167,902
Finance Leases
2021	4,282
2022	2,695
2023	2,375
2024	2,119
2025	2,074
2026	9,850
Total lease payments	23,395
Less: Imputed Interest	(4,704)
Present value of lease liabilities	$ 18,691

LEASES - Weighted average lease

LEASES - Weighted average lease terms and discount rates (Details)	Sep. 30, 2020
Weighted-average remaining lease term (years)
Operating leases, weighted-average remaining lease term	8 years 3 months 18 days
Finance leases, weighted-average remaining lease term	8 years 6 months
Weighted-average discount rate
Operating leases, weighted-average discount rate (in percentage)	4.38%
Finance leases, weighted-average discount rate (in percentage)	5.51%

CONSOLIDATING GUARANTOR AND N_3

CONSOLIDATING GUARANTOR AND NON-GUARANTOR FINANCIAL INFORMATION (Details)	12 Months Ended
	Sep. 30, 2020
Clopay Ames True Temper Holding, Corp.
Condensed Financial Statements, Captions [Line Items]
Subsidiary percentage ownership	100.00%
AMES Southern, Inc.
Condensed Financial Statements, Captions [Line Items]
Subsidiary percentage ownership	100.00%
The AMES Companies, Inc.
Condensed Financial Statements, Captions [Line Items]
Subsidiary percentage ownership	100.00%
Telephonics Corporation
Condensed Financial Statements, Captions [Line Items]
Subsidiary percentage ownership	100.00%
Clopay Building Products
Condensed Financial Statements, Captions [Line Items]
Subsidiary percentage ownership	100.00%

CONSOLIDATING GUARANTOR AND N_4

CONSOLIDATING GUARANTOR AND NON-GUARANTOR FINANCIAL INFORMATION (Details) - Summary of consolidated balance sheets - USD ($) $ in Thousands	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2017
CURRENT ASSETS
Cash and equivalents	$ 218,089	$ 72,377
Accounts receivable, net of allowances	348,124	264,450
Contract assets, net of progress payments	84,426	105,111
Inventories	413,825	442,121
Prepaid and other current assets	46,897	40,799
Assets of discontinued operations	2,091	321
Total Current Assets	1,113,452	925,179
PROPERTY, PLANT AND EQUIPMENT, net	343,964
PROPERTY, PLANT AND EQUIPMENT, net		337,326
OPERATING LEASE RIGHT-OF-USE ASSETS	161,627
GOODWILL	442,643	437,067	$ 439,395
INTANGIBLE ASSETS, net	355,028	356,639
INTERCOMPANY RECEIVABLE	0	0
EQUITY INVESTMENTS IN SUBSIDIARIES	0	0
OTHER ASSETS	32,897	15,840
ASSETS OF DISCONTINUED OPERATIONS	6,406	2,888
Total Assets	2,456,017	2,074,939
CURRENT LIABILITIES
Notes payable and current portion of long-term debt	9,922	10,525
Accounts payable and accrued liabilities	403,679	375,241
Current portion of operating lease liabilities	31,848
Liabilities of discontinued operations	3,797	4,333
Total Current Liabilities	449,246	390,099
LONG-TERM DEBT, net	1,037,042	1,093,749
LONG-TERM OPERATING LEASE LIABILITIES	136,054
INTERCOMPANY PAYABLES	0	0
OTHER LIABILITIES	126,510	109,997
LIABILITIES OF DISCONTINUED OPERATIONS	7,014	3,331
Total Liabilities	1,755,866	1,597,176
SHAREHOLDERS’ EQUITY	700,151	477,763	$ 474,391	$ 398,808
Total Liabilities and Shareholders’ Equity	2,456,017	2,074,939
Parent Company
CURRENT ASSETS
Cash and equivalents	125,353	1,649
Accounts receivable, net of allowances	0	0
Contract assets, net of progress payments	0	0
Inventories	0	0
Prepaid and other current assets	14,650	8,238
Assets of discontinued operations	0	0
Total Current Assets	140,003	9,887
PROPERTY, PLANT AND EQUIPMENT, net	1,182
PROPERTY, PLANT AND EQUIPMENT, net		1,184
OPERATING LEASE RIGHT-OF-USE ASSETS	9,209
GOODWILL	0	0
INTANGIBLE ASSETS, net	93	93
INTERCOMPANY RECEIVABLE	568,124	5,834
EQUITY INVESTMENTS IN SUBSIDIARIES	1,724,821	1,628,031
OTHER ASSETS	12,585	8,182
ASSETS OF DISCONTINUED OPERATIONS	0	0
Total Assets	2,456,017	1,653,211
CURRENT LIABILITIES
Notes payable and current portion of long-term debt	0	0
Accounts payable and accrued liabilities	37,281	41,796
Current portion of operating lease liabilities	1,849
Liabilities of discontinued operations	0	0
Total Current Liabilities	39,130	41,796
LONG-TERM DEBT, net	995,636	1,040,449
LONG-TERM OPERATING LEASE LIABILITIES	8,415
INTERCOMPANY PAYABLES	683,076	71,634
OTHER LIABILITIES	29,609	21,569
LIABILITIES OF DISCONTINUED OPERATIONS	0	0
Total Liabilities	1,755,866	1,175,448
SHAREHOLDERS’ EQUITY	700,151	477,763
Total Liabilities and Shareholders’ Equity	2,456,017	1,653,211
Guarantor Companies
CURRENT ASSETS
Cash and equivalents	35,685	25,217
Accounts receivable, net of allowances	293,943	225,870
Contract assets, net of progress payments	80,572	104,109
Inventories	347,473	372,581
Prepaid and other current assets	25,974	25,610
Assets of discontinued operations	0	0
Total Current Assets	783,647	753,387
PROPERTY, PLANT AND EQUIPMENT, net	296,082
PROPERTY, PLANT AND EQUIPMENT, net		289,282
OPERATING LEASE RIGHT-OF-USE ASSETS	129,813
GOODWILL	377,060	375,734
INTANGIBLE ASSETS, net	217,317	224,275
INTERCOMPANY RECEIVABLE	704,415	881,110
EQUITY INVESTMENTS IN SUBSIDIARIES	784,644	581,438
OTHER ASSETS	25,953	10,010
ASSETS OF DISCONTINUED OPERATIONS	0	0
Total Assets	3,318,931	3,115,236
CURRENT LIABILITIES
Notes payable and current portion of long-term debt	2,855	3,075
Accounts payable and accrued liabilities	276,580	265,055
Current portion of operating lease liabilities	24,436
Liabilities of discontinued operations	0	0
Total Current Liabilities	303,871	268,130
LONG-TERM DEBT, net	15,992	3,119
LONG-TERM OPERATING LEASE LIABILITIES	110,061
INTERCOMPANY PAYABLES	397,846	466,792
OTHER LIABILITIES	85,731	73,411
LIABILITIES OF DISCONTINUED OPERATIONS	0	0
Total Liabilities	913,501	811,452
SHAREHOLDERS’ EQUITY	2,405,430	2,303,784
Total Liabilities and Shareholders’ Equity	3,318,931	3,115,236
Non-Guarantor Companies
CURRENT ASSETS
Cash and equivalents	57,051	45,511
Accounts receivable, net of allowances	54,181	38,580
Contract assets, net of progress payments	3,854	1,002
Inventories	66,352	69,540
Prepaid and other current assets	6,273	6,951
Assets of discontinued operations	2,091	321
Total Current Assets	189,802	161,905
PROPERTY, PLANT AND EQUIPMENT, net	46,700
PROPERTY, PLANT AND EQUIPMENT, net		46,860
OPERATING LEASE RIGHT-OF-USE ASSETS	22,605
GOODWILL	65,583	61,333
INTANGIBLE ASSETS, net	137,618	132,271
INTERCOMPANY RECEIVABLE	257,013	75,684
EQUITY INVESTMENTS IN SUBSIDIARIES	3,176,855	3,233,038
OTHER ASSETS	(5,641)	(2,352)
ASSETS OF DISCONTINUED OPERATIONS	6,406	2,888
Total Assets	3,896,941	3,711,627
CURRENT LIABILITIES
Notes payable and current portion of long-term debt	7,067	7,450
Accounts payable and accrued liabilities	89,818	68,390
Current portion of operating lease liabilities	5,563
Liabilities of discontinued operations	3,797	4,333
Total Current Liabilities	106,245	80,173
LONG-TERM DEBT, net	25,414	50,181
LONG-TERM OPERATING LEASE LIABILITIES	17,578
INTERCOMPANY PAYABLES	459,599	444,557
OTHER LIABILITIES	11,170	15,017
LIABILITIES OF DISCONTINUED OPERATIONS	7,014	3,331
Total Liabilities	627,020	593,259
SHAREHOLDERS’ EQUITY	3,269,921	3,118,368
Total Liabilities and Shareholders’ Equity	3,896,941	3,711,627
Elimination
CURRENT ASSETS
Cash and equivalents	0	0
Accounts receivable, net of allowances	0	0
Contract assets, net of progress payments	0	0
Inventories	0	0
Prepaid and other current assets	0	0
Assets of discontinued operations	0	0
Total Current Assets	0	0
PROPERTY, PLANT AND EQUIPMENT, net	0
PROPERTY, PLANT AND EQUIPMENT, net		0
OPERATING LEASE RIGHT-OF-USE ASSETS	0
GOODWILL	0	0
INTANGIBLE ASSETS, net	0	0
INTERCOMPANY RECEIVABLE	(1,529,552)	(962,628)
EQUITY INVESTMENTS IN SUBSIDIARIES	(5,686,320)	(5,442,507)
OTHER ASSETS	0	0
ASSETS OF DISCONTINUED OPERATIONS	0	0
Total Assets	(7,215,872)	(6,405,135)
CURRENT LIABILITIES
Notes payable and current portion of long-term debt	0	0
Accounts payable and accrued liabilities	0	0
Current portion of operating lease liabilities	0
Liabilities of discontinued operations	0	0
Total Current Liabilities	0	0
LONG-TERM DEBT, net	0	0
LONG-TERM OPERATING LEASE LIABILITIES	0
INTERCOMPANY PAYABLES	(1,540,521)	(982,983)
OTHER LIABILITIES	0	0
LIABILITIES OF DISCONTINUED OPERATIONS	0	0
Total Liabilities	(1,540,521)	(982,983)
SHAREHOLDERS’ EQUITY	(5,675,351)	(5,422,152)
Total Liabilities and Shareholders’ Equity	$ (7,215,872)	$ (6,405,135)

CONSOLIDATING GUARANTOR AND N_5

CONSOLIDATING GUARANTOR AND NON-GUARANTOR FINANCIAL INFORMATION (Details) - Summary of consolidated statement of operations and comprehensive income - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Condensed Income Statements, Captions [Line Items]
Revenue	$ 660,673	$ 632,061	$ 566,350	$ 548,438	$ 574,164	$ 574,970	$ 549,633	$ 510,522	$ 2,407,522	$ 2,209,289	$ 1,977,918
Cost of goods and services									1,766,096	1,625,815	1,466,600
Gross profit	174,470	165,003	152,032	149,921	158,458	151,699	133,537	139,780	641,426	583,474	511,318
Selling, general and administrative expenses									486,398	447,163	418,517
Income from continuing operations									155,028	136,311	92,801
Other income (expense)
Interest income (expense), net									(65,791)	(67,260)	(63,871)
Loss from debt extinguishment		969	5,245						7,925	0	0
Other, net									1,445	3,127	4,880
Total other income (expense)									(72,271)	(64,133)	(58,991)
Income before taxes from continuing operations									82,757	72,178	33,810
Provision for income taxes									29,328	26,556	555
Income (loss) before equity in net income of subsidiaries									53,429	45,622	33,255
Equity in net income (loss) of subsidiaries									0	0	0
Income (loss) from continuing operations	$ 20,091	$ 21,831	$ 895	$ 10,612	$ 16,251	$ 14,128	$ 6,490	$ 8,753	53,429	45,622	33,255
Income (loss) from operations of discontinued businesses									0	(11,050)	119,981
Provision for income taxes									0	(2,715)	27,558
Income (loss) from discontinued operations									0	(8,335)	92,423
Net income									53,429	37,287	125,678
Comprehensive income (loss)									47,253	5,483	152,047
Parent Company
Condensed Income Statements, Captions [Line Items]
Revenue									0	0	0
Cost of goods and services									0	0	0
Gross profit									0	0	0
Selling, general and administrative expenses									24,876	22,566	37,540
Income from continuing operations									(24,876)	(22,566)	(37,540)
Other income (expense)
Interest income (expense), net									(27,129)	(27,883)	(23,911)
Loss from debt extinguishment									7,925
Other, net									(523)	(778)	(7,666)
Total other income (expense)									(35,577)	(28,661)	(31,577)
Income before taxes from continuing operations									(60,453)	(51,227)	(69,117)
Provision for income taxes									(11,907)	(7,425)	(17,692)
Income (loss) before equity in net income of subsidiaries									(48,546)	(43,802)	(51,425)
Equity in net income (loss) of subsidiaries									101,975	81,089	177,103
Income (loss) from continuing operations										37,287	125,678
Income (loss) from operations of discontinued businesses										0	0
Provision for income taxes										0	0
Income (loss) from discontinued operations										0	0
Net income									53,429	37,287	125,678
Comprehensive income (loss)									47,253	5,483	152,047
Guarantor Companies
Condensed Income Statements, Captions [Line Items]
Revenue									1,938,972	1,808,824	1,638,792
Cost of goods and services									1,450,924	1,353,663	1,250,261
Gross profit									488,048	455,161	388,531
Selling, general and administrative expenses									357,901	327,306	290,475
Income from continuing operations									130,147	127,855	98,056
Other income (expense)
Interest income (expense), net									(38,301)	(39,288)	(31,913)
Loss from debt extinguishment									0
Other, net									(7,946)	(17,699)	125,531
Total other income (expense)									(46,247)	(56,987)	93,618
Income before taxes from continuing operations									83,900	70,868	191,674
Provision for income taxes									25,445	20,534	9,546
Income (loss) before equity in net income of subsidiaries									58,455	50,334	182,128
Equity in net income (loss) of subsidiaries									43,505	44,303	(151,864)
Income (loss) from continuing operations										94,637	30,264
Income (loss) from operations of discontinued businesses										0	119,981
Provision for income taxes										0	27,558
Income (loss) from discontinued operations										0	92,423
Net income									101,960	94,637	122,687
Comprehensive income (loss)									101,960	87,851	143,936
Non-Guarantor Companies
Condensed Income Statements, Captions [Line Items]
Revenue									507,621	437,542	367,149
Cost of goods and services									355,696	310,707	245,687
Gross profit									151,925	126,835	121,462
Selling, general and administrative expenses									103,991	97,661	90,872
Income from continuing operations									47,934	29,174	30,590
Other income (expense)
Interest income (expense), net									(361)	(89)	(8,047)
Loss from debt extinguishment									0
Other, net									11,762	23,452	(111,248)
Total other income (expense)									11,401	23,363	(119,295)
Income before taxes from continuing operations									59,335	52,537	(88,705)
Provision for income taxes									15,788	13,447	8,743
Income (loss) before equity in net income of subsidiaries									43,547	39,090	(97,448)
Equity in net income (loss) of subsidiaries									58,455	50,334	182,128
Income (loss) from continuing operations										89,424	84,680
Income (loss) from operations of discontinued businesses										(11,050)	0
Provision for income taxes										(2,715)	0
Income (loss) from discontinued operations										(8,335)	0
Net income									102,002	81,089	84,680
Comprehensive income (loss)									102,002	87,875	81,389
Elimination
Condensed Income Statements, Captions [Line Items]
Revenue									(39,071)	(37,077)	(28,023)
Cost of goods and services									(40,524)	(38,555)	(29,348)
Gross profit									1,453	1,478	1,325
Selling, general and administrative expenses									(370)	(370)	(370)
Income from continuing operations									1,823	1,848	1,695
Other income (expense)
Interest income (expense), net									0	0	0
Loss from debt extinguishment									0
Other, net									(1,848)	(1,848)	(1,737)
Total other income (expense)									(1,848)	(1,848)	(1,737)
Income before taxes from continuing operations									(25)	0	(42)
Provision for income taxes									2	0	(42)
Income (loss) before equity in net income of subsidiaries									(27)	0	0
Equity in net income (loss) of subsidiaries									(203,935)	(175,726)	(207,367)
Income (loss) from continuing operations										(175,726)	(207,367)
Income (loss) from operations of discontinued businesses										0	0
Provision for income taxes										0	0
Income (loss) from discontinued operations										0	0
Net income									(203,962)	(175,726)	(207,367)
Comprehensive income (loss)									$ (203,962)	$ (175,726)	$ (225,325)

CONSOLIDATING GUARANTOR AND N_6

CONSOLIDATING GUARANTOR AND NON-GUARANTOR FINANCIAL INFORMATION (Details) - Summary of consolidated cash flows - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
CASH FLOWS FROM OPERATING ACTIVITIES - CONTINUING OPERATIONS:
Net income	$ 53,429	$ 37,287	$ 125,678
Net (income) loss from discontinued operations	0	8,335	(92,423)
Net cash provided by operating activities	137,029	113,958	58,192
CASH FLOWS FROM INVESTING ACTIVITIES - CONTINUING OPERATIONS:
Acquisition of property, plant and equipment	(48,998)	(45,361)	(50,138)
Acquired business, net of cash acquired	(10,531)	(9,219)	(430,932)
Proceeds (payments) from sale of business	0	(9,500)	474,727
Insurance proceeds (payments)	0	(10,604)	8,254
Proceeds from sale of property, plant and equipment	352	280	663
Investment purchases	(130)	(149)	0
Net cash provided by (used in) investing activities - continuing operations	(59,307)	(74,553)	2,574
CASH FLOWS FROM FINANCING ACTIVITIES - CONTINUING OPERATIONS:
Proceeds from issuance of common stock	178,165	0	0
Purchase of shares for treasury	(7,479)	(1,478)	(45,605)
Proceeds from long-term debt	1,240,080	201,748	443,058
Payments of long-term debt	(1,308,915)	(218,248)	(300,993)
Change in short-term borrowings	0	(366)	144
Financing costs	(17,384)	(1,090)	(7,793)
Contingent consideration for acquired businesses	(1,733)	(1,686)	0
Acquisition costs	(1,733)
Purchase of ESOP shares			0
Dividends paid	(14,529)	(13,676)	(49,797)
Other, net	(15)	(180)	51
Net cash provided by (used) in financing activities - continuing operations	68,190	(34,976)	39,065
CASH FLOWS FROM DISCONTINUED OPERATIONS:
Net cash provided by (used in) discontinued operations	(2,577)	(2,123)	(78,927)
Effect of exchange rate changes on cash and equivalents	2,377	313	1,173
NET DECREASE IN CASH AND EQUIVALENTS	145,712	2,619	22,077
CASH AND EQUIVALENTS AT BEGINNING OF PERIOD	72,377	69,758	47,681
CASH AND EQUIVALENTS AT END OF PERIOD	218,089	72,377	69,758
Parent Company
CASH FLOWS FROM OPERATING ACTIVITIES - CONTINUING OPERATIONS:
Net income	53,429	37,287	125,678
Net (income) loss from discontinued operations		0	0
Net cash provided by operating activities	23,114	42,159	381,417
CASH FLOWS FROM INVESTING ACTIVITIES - CONTINUING OPERATIONS:
Acquisition of property, plant and equipment	(348)	(542)	(544)
Acquired business, net of cash acquired	0	(9,219)	(368,936)
Proceeds (payments) from sale of business		(9,500)	0
Insurance proceeds (payments)		(10,604)	8,254
Proceeds from sale of property, plant and equipment	0	0	0
Investment purchases	(130)	(149)
Net cash provided by (used in) investing activities - continuing operations	(478)	(30,014)	(361,226)
CASH FLOWS FROM FINANCING ACTIVITIES - CONTINUING OPERATIONS:
Proceeds from issuance of common stock	178,165
Purchase of shares for treasury	(7,479)	(1,478)	(45,605)
Proceeds from long-term debt	1,234,723	163,297	411,623
Payments of long-term debt	(1,272,688)	(173,345)	(269,478)
Change in short-term borrowings		0	0
Financing costs	(17,384)	(1,090)	(7,793)
Contingent consideration for acquired businesses		0
Acquisition costs	0
Purchase of ESOP shares			0
Dividends paid	(14,529)	(13,676)	(49,797)
Other, net	260	(180)	(46,405)
Net cash provided by (used) in financing activities - continuing operations	101,068	(26,472)	(7,455)
CASH FLOWS FROM DISCONTINUED OPERATIONS:
Net cash provided by (used in) discontinued operations	0	0	0
Effect of exchange rate changes on cash and equivalents	0	0	0
NET DECREASE IN CASH AND EQUIVALENTS	123,704	(14,327)	12,736
CASH AND EQUIVALENTS AT BEGINNING OF PERIOD	1,649	15,976	3,240
CASH AND EQUIVALENTS AT END OF PERIOD	125,353	1,649	15,976
Guarantor Companies
CASH FLOWS FROM OPERATING ACTIVITIES - CONTINUING OPERATIONS:
Net income	101,960	94,637	122,687
Net (income) loss from discontinued operations		0	(92,423)
Net cash provided by operating activities	55,353	41,992	(405,174)
CASH FLOWS FROM INVESTING ACTIVITIES - CONTINUING OPERATIONS:
Acquisition of property, plant and equipment	(42,268)	(38,872)	(41,531)
Acquired business, net of cash acquired	0	0	(4,843)
Proceeds (payments) from sale of business		0	474,727
Insurance proceeds (payments)		0	0
Proceeds from sale of property, plant and equipment	345	254	62
Investment purchases	0	0
Net cash provided by (used in) investing activities - continuing operations	(41,923)	(38,618)	428,415
CASH FLOWS FROM FINANCING ACTIVITIES - CONTINUING OPERATIONS:
Proceeds from issuance of common stock	0
Purchase of shares for treasury	0	0	0
Proceeds from long-term debt	0	0	2,125
Payments of long-term debt	(3,421)	(2,973)	(5,403)
Change in short-term borrowings		(366)	144
Financing costs	0	0	0
Contingent consideration for acquired businesses		0
Acquisition costs	0
Purchase of ESOP shares			0
Dividends paid	0	0	0
Other, net	580	8,830	4,733
Net cash provided by (used) in financing activities - continuing operations	(2,841)	5,491	1,599
CASH FLOWS FROM DISCONTINUED OPERATIONS:
Net cash provided by (used in) discontinued operations	0	0	(16,394)
Effect of exchange rate changes on cash and equivalents	(121)	(1)	(159)
NET DECREASE IN CASH AND EQUIVALENTS	10,468	8,864	8,287
CASH AND EQUIVALENTS AT BEGINNING OF PERIOD	25,217	16,353	8,066
CASH AND EQUIVALENTS AT END OF PERIOD	35,685	25,217	16,353
Non-Guarantor Companies
CASH FLOWS FROM OPERATING ACTIVITIES - CONTINUING OPERATIONS:
Net income	102,002	81,089	84,680
Net (income) loss from discontinued operations		8,335	0
Net cash provided by operating activities	58,562	29,807	108,981
CASH FLOWS FROM INVESTING ACTIVITIES - CONTINUING OPERATIONS:
Acquisition of property, plant and equipment	(6,382)	(5,947)	(8,063)
Acquired business, net of cash acquired	(10,531)	0	(57,153)
Proceeds (payments) from sale of business		0	0
Insurance proceeds (payments)		0	0
Proceeds from sale of property, plant and equipment	7	26	601
Investment purchases	0	0
Net cash provided by (used in) investing activities - continuing operations	(16,906)	(5,921)	(64,615)
CASH FLOWS FROM FINANCING ACTIVITIES - CONTINUING OPERATIONS:
Proceeds from issuance of common stock	0
Purchase of shares for treasury	0	0	0
Proceeds from long-term debt	5,357	38,451	29,310
Payments of long-term debt	(32,806)	(41,930)	(26,112)
Change in short-term borrowings		0	0
Financing costs	0	0	0
Contingent consideration for acquired businesses		(1,686)
Acquisition costs	(1,733)
Purchase of ESOP shares			0
Dividends paid	0	0	0
Other, net	(855)	(8,830)	14,691
Net cash provided by (used) in financing activities - continuing operations	(30,037)	(13,995)	17,889
CASH FLOWS FROM DISCONTINUED OPERATIONS:
Net cash provided by (used in) discontinued operations	(2,577)	(2,123)	(62,533)
Effect of exchange rate changes on cash and equivalents	2,498	314	1,332
NET DECREASE IN CASH AND EQUIVALENTS	11,540	8,082	1,054
CASH AND EQUIVALENTS AT BEGINNING OF PERIOD	45,511	37,429	36,375
CASH AND EQUIVALENTS AT END OF PERIOD	57,051	45,511	37,429
Elimination
CASH FLOWS FROM OPERATING ACTIVITIES - CONTINUING OPERATIONS:
Net income	(203,962)	(175,726)	(207,367)
Net (income) loss from discontinued operations		0	0
Net cash provided by operating activities	0	0	(27,032)
CASH FLOWS FROM INVESTING ACTIVITIES - CONTINUING OPERATIONS:
Acquisition of property, plant and equipment	0	0	0
Acquired business, net of cash acquired	0	0	0
Proceeds (payments) from sale of business		0	0
Insurance proceeds (payments)		0	0
Proceeds from sale of property, plant and equipment	0	0	0
Investment purchases	0	0
Net cash provided by (used in) investing activities - continuing operations	0	0	0
CASH FLOWS FROM FINANCING ACTIVITIES - CONTINUING OPERATIONS:
Proceeds from issuance of common stock	0
Purchase of shares for treasury	0	0	0
Proceeds from long-term debt	0	0	0
Payments of long-term debt	0	0	0
Change in short-term borrowings		0	0
Financing costs	0	0	0
Contingent consideration for acquired businesses		0
Acquisition costs	0
Purchase of ESOP shares			0
Dividends paid	0	0	0
Other, net	0	0	27,032
Net cash provided by (used) in financing activities - continuing operations	0	0	27,032
CASH FLOWS FROM DISCONTINUED OPERATIONS:
Net cash provided by (used in) discontinued operations	0	0	0
Effect of exchange rate changes on cash and equivalents	0	0	0
NET DECREASE IN CASH AND EQUIVALENTS	0	0	0
CASH AND EQUIVALENTS AT BEGINNING OF PERIOD	0	0	0
CASH AND EQUIVALENTS AT END OF PERIOD	$ 0	$ 0	$ 0

SUBSEQUENT EVENTS (Details)

SUBSEQUENT EVENTS (Details)	Nov. 12, 2020$ / shares
Subsequent Event
Subsequent Event [Line Items]
Dividends payable, amount per share (in dollars per share)	$ 0.08

SCHEDULE II VALUATION AND QUA_2

SCHEDULE II VALUATION AND QUALIFYING ACCOUNTS (Details) - Schedule of Valuation and Qualifying Accounts - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
SEC Schedule, 12-09, Allowance, Credit Loss
Segment Reporting Information [Line Items]
Balance at Beginning of Year	$ 7,881	$ 6,408	$ 5,966
Recorded to Cost and Expense	14,394	6,254	4,048
Accounts Written Off, net	(4,516)	(4,799)	(4,749)
Other	(1)	18	1,143
Balance at End of Year	17,758	7,881	6,408
Inventory valuation
Segment Reporting Information [Line Items]
Balance at Beginning of Year	26,169	26,065	16,419
Recorded to Cost and Expense	10,542	2,774	1,924
Accounts Written Off, net	(3,412)	(2,614)	(306)
Other	325	(56)	8,028
Balance at End of Year	33,624	26,169	26,065
Deferred tax valuation allowance
Segment Reporting Information [Line Items]
Balance at Beginning of Year	10,823	8,520	17,466
Recorded to Cost and Expense	(999)	2,303	(8,946)
Accounts Written Off, net	0	0	0
Other	0	0	0
Balance at End of Year	9,824	10,823	8,520
Bad debts | SEC Schedule, 12-09, Allowance, Credit Loss
Segment Reporting Information [Line Items]
Balance at Beginning of Year	1,881	1,824	1,109
Recorded to Cost and Expense	2,231	464	(40)
Accounts Written Off, net	(255)	(425)	11
Other	(1)	18	744
Balance at End of Year	3,856	1,881	1,824
Sales returns and allowances | SEC Schedule, 12-09, Allowance, Credit Loss
Segment Reporting Information [Line Items]
Balance at Beginning of Year	6,000	4,584	4,857
Recorded to Cost and Expense	12,163	5,790	4,088
Accounts Written Off, net	(4,261)	(4,374)	(4,760)
Other	0	0	399
Balance at End of Year	$ 13,902	$ 6,000	$ 4,584