Azenta (AZTA) 10-Q 5 Aug 21 2021 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - $ / shares	9 Months Ended
	Jun. 30, 2021	Jul. 29, 2021
Cover [Abstract]
Entity Central Index Key	0000933974
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Jun. 30, 2021
Document Transition Report	false
Entity File Number	000-25434
Entity Registrant Name	BROOKS AUTOMATION, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	04-3040660
Entity Address, Address Line One	15 Elizabeth Drive
Entity Address, City or Town	Chelmsford
Entity Address, State or Province	MA
Entity Address, Postal Zip Code	01824
City Area Code	978
Local Phone Number	262-2400
Title of 12(b) Security	Common Stock, $0.01 par value
Entity Listing, Par Value Per Share	$ 0.01
Trading Symbol	BRKS
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		74,296,729
Current Fiscal Year End Date	--09-30
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q3
Amendment Flag	false

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Jun. 30, 2021	Sep. 30, 2020
Current assets
Cash and cash equivalents	$ 269,862	$ 295,649
Marketable securities	101	67
Accounts receivable, net	234,079	188,291
Inventories	154,720	114,834
Prepaid expenses and other current assets	58,455	50,612
Total current assets	717,217	649,453
Property, plant and equipment, net	146,522	117,665
Long-term marketable securities	3,637	3,101
Long-term deferred tax assets	4,447	4,979
Goodwill	551,326	501,536
Intangible assets, net	254,937	218,325
Other assets	85,169	64,066
Total assets	1,763,255	1,559,125
Current liabilities
Current portion of long-term debt		827
Accounts payable	98,192	61,758
Deferred revenue	35,421	31,357
Accrued warranty and retrofit costs	8,132	8,201
Accrued compensation and benefits	43,803	43,267
Accrued restructuring costs	29	181
Accrued income taxes payable	22,232	10,094
Accrued expenses and other current liabilities	103,251	55,433
Total current liabilities	311,060	211,118
Long-term debt	49,651	49,588
Long-term tax reserves	18,410	19,168
Long-term deferred tax liabilities	16,295	17,798
Long-term pension liabilities	6,536	6,406
Long-term operating lease liabilities	45,034	31,855
Other long-term liabilities	8,440	9,578
Total liabilities	455,426	345,511
Commitments and contingencies (Note 17)
Stockholders' Equity
Preferred stock, $0.01 par value - 1,000,000 shares authorized, no shares issued or outstanding
Common stock, $0.01 par value - 125,000,000 shares authorized, 87,758,598 shares issued and 74,296,729 shares outstanding at June 30, 2021, 87,293,710 shares issued and 73,831,841 shares outstanding at September 30, 2020	878	873
Additional paid-in capital	1,965,705	1,942,850
Accumulated other comprehensive income	26,619	21,919
Treasury stock, at cost- 13,461,869 shares	(200,956)	(200,956)
Accumulated deficit	(484,417)	(551,072)
Total stockholders' equity	1,307,829	1,213,614
Total liabilities and stockholders' equity	$ 1,763,255	$ 1,559,125

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Jun. 30, 2021	Sep. 30, 2020
Preferred Stock, Number of Shares, Par Value and Other Disclosures [Abstract]
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized	1,000,000	1,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common Stock, Number of Shares, Par Value and Other Disclosures [Abstract]
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized	125,000,000	125,000,000
Common stock, shares issued	87,758,598	87,293,710
Common stock, shares outstanding	74,296,729	73,831,841
Treasury Stock, Number of Shares and Restriction Disclosures [Abstract]
Treasury stock, shares	13,461,869	13,461,869

CONSOLIDATED STATEMENTS OF OPER

CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Revenue
Total revenue	$ 315,349	$ 220,350	$ 851,439	$ 651,077
Cost of revenue
Total cost of revenue	170,949	127,562	466,637	383,022
Gross profit	144,400	92,788	384,802	268,055
Operating expenses
Research and development	18,284	14,004	51,310	43,727
Selling, general and administrative	75,883	59,714	221,646	178,866
Restructuring charges		(29)	179	1,125
Total operating expenses	94,167	73,689	273,135	223,718
Operating income	50,233	19,099	111,667	44,337
Interest income	409	29	503	865
Interest expense	(477)	(810)	(1,485)	(2,265)
Other income (expenses), net	(1,625)	498	(147)	(1,318)
Income before income taxes	48,540	18,816	110,538	41,619
Income tax provision	9,370	5,120	20,428	5,557
Income from continuing operations	39,170	13,696	90,110	36,062
Loss from discontinued operations, net of tax	(4)		(1,168)	(182)
Net income	$ 39,166	$ 13,696	$ 88,942	$ 35,880
Basic net income per share:
Income from continuing operations (in dollars per share)	$ 0.53	$ 0.19	$ 1.21	$ 0.49
Loss from discontinued operations, net of tax (in dollars per share)	0		(0.02)	0
Basic net income per share (in dollars per share)	0.53	0.19	1.20	0.49
Diluted net income per share:
Income from continuing operations (in dollars per share)	0.53	0.19	1.21	0.49
Loss from discontinued operations, net of tax (in dollars per share)	0		(0.02)	0
Diluted net income per share (in dollars per share)	$ 0.53	$ 0.19	$ 1.20	$ 0.49
Weighted average shares used in computing net income per share:
Basic (in shares)	74,296	73,759	74,195	73,473
Diluted (in shares)	74,495	73,860	74,420	73,766
Products
Revenue
Total revenue	$ 215,843	$ 142,323	$ 565,829	$ 413,329
Cost of revenue
Total cost of revenue	120,387	81,989	317,472	245,930
Services
Revenue
Total revenue	99,506	78,027	285,610	237,748
Cost of revenue
Total cost of revenue	$ 50,562	$ 45,573	$ 149,165	$ 137,092

CONSOLIDATED STATEMENTS OF COMP

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Statement of Comprehensive Income [Abstract]
Net income	$ 39,166	$ 13,696	$ 88,942	$ 35,880
Other comprehensive income, net of tax:
Foreign currency translation adjustments	4,003	3,691	4,721	7,484
Unrealized gains (losses) on marketable securities, net of tax effects of $0 during each of the three and nine months ended June 30, 2021, and $0 during each of the three and nine months ended June 30, 2020				7
Actuarial losses, net of tax effects of $3 and $4 during the three and nine months ended June 30, 2021, respectively, $2 and $4 during the three and nine months ended June 30, 2020 respectively	(21)	(13)	(20)	(25)
Total other comprehensive income, net of tax	3,982	3,678	4,701	7,466
Comprehensive income	$ 43,148	$ 17,374	$ 93,643	$ 43,346

CONSOLIDATED STATEMENTS OF CO_2

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Parenthetical) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Statement of Comprehensive Income [Abstract]
Unrealized (losses) gains on marketable securities, tax	$ 0	$ 0	$ 0	$ 0
Actuarial gains (losses)	$ 3	$ 4	$ 2	$ 4

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Jun. 30, 2021	Jun. 30, 2020
Cash flows from operating activities
Net income	$ 88,942	$ 35,880
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	48,684	49,760
Impairment of property, plant and equipment		301
Stock-based compensation	20,277	12,348
Amortization of premium on marketable securities and deferred financing costs	169	177
Deferred income taxes	(10,293)	(9,319)
Other losses on disposals of assets	225	163
Adjustment to the gain on divestiture, net of tax	948	319
Taxes paid stemming from divestiture		(91,500)
Changes in operating assets and liabilities, net of acquisitions and divestiture:
Accounts receivable	(40,286)	(15,719)
Inventories	(32,532)	(17,695)
Prepaid expenses and other assets	4,000	12,554
Accounts payable	23,327	11,032
Deferred revenue	(1,564)	214
Accrued warranty and retrofit costs	(286)	580
Accrued compensation and tax withholdings	(338)	1,928
Accrued restructuring costs	(153)	(609)
Accrued expenses and other liabilities	21,625	(4,347)
Net cash provided by (used in) operating activities	122,745	(13,933)
Cash flows from investing activities
Purchases of property, plant and equipment	(34,606)	(29,685)
Purchases of marketable securities	(100)	(10,843)
Sales of marketable securities	25	2,492
Maturities of marketable securities	25	42,226
Adjustment to proceeds from divestiture - NOT USED IN 10-K	(1,802)
Acquisitions, net of cash acquired	(92,375)	(15,743)
Issuance of a note receivable		(1,000)
Net cash used in by investing activities	(128,833)	(12,553)
Cash flows from financing activities
Proceeds from issuance of common stock	2,583	2,332
Principal payments on debt	(828)	(828)
Payments of finance leases	(915)	(957)
Common stock dividends paid	(22,288)	(22,127)
Net cash used in financing activities	(21,448)	(21,580)
Effects of exchange rate changes on cash and cash equivalents	7,582	3,095
Net decrease in cash, cash equivalents and restricted cash	(19,954)	(44,971)
Cash, cash equivalents and restricted cash, beginning of period	302,526	305,171
Cash, cash equivalents and restricted cash, end of period	282,572	260,200
Supplemental disclosure of non-cash investing and financing activities:
Purchases of property, plant and equipment included in accounts payable	$ 14,516	$ 2,020

CONSOLIDATED STATEMENTS OF CA_2

CONSOLIDATED STATEMENTS OF CASH FLOWS (Parenthetical) - USD ($) $ in Thousands	Jun. 30, 2021	Jun. 30, 2020
Reconciliation of cash, cash equivalents, and restricted cash to the consolidated balance sheets
Cash and cash equivalents	$ 269,862	$ 256,633
Short-term restricted cash included in prepaid expenses and other current assets	3,570	3,567
Long-term restricted cash included in other assets	9,140
Total cash, cash equivalents and restricted cash shown in the consolidated statements of cash flows	$ 282,572	$ 260,200
Restricted Cash, Current, Statement of Financial Position	Prepaid expenses and other current assets	Prepaid expenses and other current assets
Restricted Cash, Noncurrent, Statement of Financial Position	Other assets	Other assets

CONSOLIDATED STATEMENTS OF CHAN

CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS EQUITY - USD ($) $ in Thousands	Common Stock	Additional Paid-In Capital	Accumulated Other Comprehensive Income (Loss)	Accumulated Deficit	Treasury Stock	Total
Beginning Balance at Sep. 30, 2019	$ 857	$ 1,921,954	$ 3,511	$ (586,412)	$ (200,956)	$ 1,138,954
Beginning Balance (in shares) at Sep. 30, 2019	85,759,700
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued under restricted stock and purchase plans, net	$ 15	2,317				2,332
Shares issued under restricted stock and purchase plans, net (in shares)	1,462,415
Stock-based compensation		12,348				12,348
Common stock dividends declared				(22,127)		(22,127)
Foreign currency translation adjustments			7,484			7,484
Changes in unrealized losses on marketable securities, net of tax effects			7			7
Actuarial loss, net of tax effects			(25)			(25)
Net income				35,880		35,880
Ending Balance at Jun. 30, 2020	$ 872	1,936,619	10,977	(572,659)	(200,956)	1,174,853
Ending Balance (in shares) at Jun. 30, 2020	87,222,115
Beginning Balance at Mar. 31, 2020	$ 872	1,932,893	7,299	(578,975)	(200,956)	1,161,133
Beginning Balance (in shares) at Mar. 31, 2020	87,214,622
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued under restricted stock and purchase plans, net		1				1
Shares issued under restricted stock and purchase plans, net (in shares)	7,493
Stock-based compensation		3,725				3,725
Common stock dividends declared				(7,380)		(7,380)
Foreign currency translation adjustments			3,691			3,691
Actuarial loss, net of tax effects			(13)			(13)
Net income				13,696		13,696
Ending Balance at Jun. 30, 2020	$ 872	1,936,619	10,977	(572,659)	(200,956)	1,174,853
Ending Balance (in shares) at Jun. 30, 2020	87,222,115
Beginning Balance at Sep. 30, 2020	$ 873	1,942,850	21,919	(551,072)	(200,956)	$ 1,213,614
Beginning Balance (in shares) at Sep. 30, 2020	87,293,710					73,831,841
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued under restricted stock and purchase plans, net	$ 5	2,578				$ 2,583
Shares issued under restricted stock and purchase plans, net (in shares)	464,888
Stock-based compensation		20,277				20,277
Common stock dividends declared				(22,287)		(22,287)
Foreign currency translation adjustments			4,720			4,720
Actuarial loss, net of tax effects			(20)			(20)
Net income				88,942		88,942
Ending Balance at Jun. 30, 2021	$ 878	1,965,705	26,619	(484,417)	(200,956)	$ 1,307,829
Ending Balance (in shares) at Jun. 30, 2021	87,758,598					74,296,729
Beginning Balance at Mar. 31, 2021	$ 878	1,959,619	22,637	(516,152)	(200,956)	$ 1,266,026
Beginning Balance (in shares) at Mar. 31, 2021	87,755,666
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued under restricted stock and purchase plans, net (in shares)	2,932
Stock-based compensation		6,086				6,086
Common stock dividends declared				(7,431)		(7,431)
Foreign currency translation adjustments			4,003			4,003
Actuarial loss, net of tax effects			(21)			(21)
Net income				39,166		39,166
Ending Balance at Jun. 30, 2021	$ 878	$ 1,965,705	$ 26,619	$ (484,417)	$ (200,956)	$ 1,307,829
Ending Balance (in shares) at Jun. 30, 2021	87,758,598					74,296,729

CONSOLIDATED STATEMENTS OF CH_2

CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS EQUITY (Parenthetical) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Statement of Stockholders' Equity [Abstract]
Dividend declared per share (in dollars per share)	$ 0.10	$ 0.10	$ 0.30	$ 0.30
Changes in unrealized gains (losses) on marketable securities, tax				$ 0
Actuarial losses, tax	$ 3	$ 2	$ 4	$ 4

Basis of Presentation

Basis of Presentation	9 Months Ended
	Jun. 30, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	1. Basis of Presentation The unaudited consolidated financial statements of Brooks Automation, Inc. and its subsidiaries (“Brooks”, or the “Company”) included herein have been prepared in accordance with accounting principles generally accepted in the United States (“GAAP”). All intercompany accounts and transactions have been eliminated in consolidation. In the opinion of management, all material adjustments, which are of a normal and recurring nature and necessary for a fair statement of the financial position and results of operations and cash flows for the periods presented, have been reflected in the accompanying unaudited consolidated financial statements. The results of operations for the interim periods are not necessarily indicative of the results of operations to be expected for the full fiscal year. Certain information and footnote disclosures normally included in the Company’s annual consolidated financial statements have been condensed or omitted and, accordingly, the accompanying financial information should be read in conjunction with the audited consolidated financial statements and notes thereto contained in the Company’s Annual Report on Form 10-K filed with the United States Securities and Exchange Commission (the “SEC”) for the fiscal year ended September 30, 2020 (the “2020 Annual Report on Form 10-K”). The accompanying Consolidated Balance Sheet as of September 30, 2020 was derived from the audited annual consolidated financial statements as of the period then ended. Discontinued Operations In the fourth quarter of fiscal year 2018, the Company entered into a definitive agreement to sell its semiconductor cryogenics business (the “Disposition”) to Edwards Vacuum LLC (a member of the Atlas Copco Group) (“Edwards”). The Company determined that the semiconductor cryogenics business met the “held for sale” criteria and the “discontinued operations” criteria in accordance with Financial Accounting Standard Boards (“FASB”) Accounting Standards Codification (“ASC”) 205, Presentation of Financial Statements Separation On May 10, 2021, the Company announced its intention to separate its business into two independent, publicly traded companies. The Company plans to spin-off its semiconductor business, which operates as the Semiconductor Solutions Group segment through a pro rata distribution of shares to the Company’s common stockholders. Completion of the proposed spin-off is subject to certain conditions, including final approval by the Company’s Board of Directors. The Company is targeting to complete the separation of the business before the end of calendar year 2021. ​ Risks and Uncertainties The Company is subject to risks common to companies in the markets it serves, including, but not limited to, global economic and financial market conditions, fluctuations in customer demand, acceptance of new products, development by its competitors of new technological innovations, risk of disruption in its supply chain, the implementation of tariffs and export controls, dependence on key personnel, protection of proprietary technology, and compliance with domestic and foreign regulatory authorities and agencies. ​ During the COVID-19 pandemic, the Company’s facilities have remained operational with only required personnel on site, and the balance of employees working from home. The Company’s semiconductor and life sciences business segments fall within the classification of an “Essential Critical Infrastructure Sector” as defined by the U.S. Department of Homeland Security and have continued operations during the COVID-19 pandemic. The Company has followed government guidance in each region and country and has implemented U.S. Centers for Disease Control and Prevention social distancing guidelines and other applicable best practices to protect the health and safety of the Company’s employees. The COVID-19 pandemic has not had a substantial negative impact on the Company’s financial results and a portion of the impact has been mitigated by the Company’s realignment of resources to satisfy incremental orders related to virus research. As states safely reopen the economy, get people back to work, and ease social restrictions while minimizing the health impacts of COVID-19, future impacts on the Company’s financial results will depend on future variants of the virus and vaccine effectiveness against the variants, which are not fully determinable, as the full impact of the pandemic on the economy and markets which the Company serves is as yet unknown. The Company’s financial results will also depend on variables including reduced demand from its customers, the degree that the supply chain may be constrained which could impact its delivery of product and the potential impact to its operations if there is a significant outbreak among the Company’s employees, as well as the amount of incremental demand caused by research and treatments in the areas of COVID-19 or related threats.

Summary of Significant Accounti

Summary of Significant Accounting Policies	9 Months Ended
	Jun. 30, 2021
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	2. Summary of Significant Accounting Policies Use of Estimates The preparation of unaudited consolidated financial statements in conformity with GAAP requires management to make certain estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the unaudited consolidated financial statements and the reported amounts of revenue and expenses during the reporting period. Significant estimates are associated with recording accounts receivable, inventories, goodwill, intangible assets other than goodwill, long-lived assets, derivative financial instruments, deferred income taxes, warranty obligations, revenue recognized in accordance with the percentage of completion method, and stock-based compensation expense. The Company bases its estimates on historical experience and various other assumptions, including in certain circumstances future projections that management believes to be reasonable under the circumstances. Although the Company regularly assesses these estimates, actual results could differ from those estimates. Changes in estimates are recorded in the period in which they occur and become known. The full extent to which the COVID-19 pandemic will directly or indirectly impact the Company’s business, including results of operations and financial condition, sales, expenses, reserves and allowances, manufacturing and employee-related amounts, will depend on future developments that are highly uncertain. This includes results from new information that may emerge concerning COVID-19 and any actions taken to contain or treat COVID-19, as well as the economic impact on local, regional, national and international customers and markets. The Company has made estimates of the impact of COVID-19 within its financial statements and there may be changes to those estimates in future periods. ​ Foreign Currency Translation Certain transactions of the Company and its subsidiaries are denominated in currencies other than their functional currency. Foreign currency exchange gains and losses generated from the settlement and remeasurement of these transactions are recognized in earnings and presented within “Other income (expenses), net” in the Company’s unaudited Consolidated Statements of Operations. Net foreign currency transaction and remeasurement losses were $1.6 million and less than $0.1 million during the three months ended June 30, 2021 and 2020, respectively. Net foreign currency transaction and remeasurement losses were $1.2 million and $2.8 million during the nine months ended June 30, 2021 and 2020, respectively. Derivative Financial Instruments The Company has transactions and balances denominated in currencies other than U.S. dollars. Most of these transactions or balances are denominated in Euros, British Pounds and a variety of Asian currencies. The Company enters into foreign exchange contracts to reduce its exposure to currency fluctuations. The arrangements typically mature in three months or less and they do not qualify for hedge accounting. Net gains and losses related to these contracts are recorded as a component of "Other income (expenses), net" in the accompanying unaudited Consolidated Statements of Operations and are as follows for the three and nine months ended June 30, 2021 and 2020 (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ Nine Months Ended ​ ​ ​ June 30, ​ June 30, ​ ​ 2021 2020 2021 2020 Realized losses on derivatives not designated as hedging instruments ​ $ (961) ​ $ (1,719) ​ $ (7,295) ​ $ (963) ​ ​ The fair values of the forward contracts are recorded in the accompanying unaudited Consolidated Balance Sheets as “Prepaid expenses and other current assets” and “Accrued expenses and other current liabilities”. Foreign exchange contract assets and liabilities are measured and reported at fair value based on observable market inputs and classified within Level 2 of the fair value hierarchy described below due to a lack of an active market for these contracts. Fair Value Measurements The Company measures certain financial assets and liabilities, including cash equivalents and available for sale securities, at fair value. FASB ASC 820, Fair Value Measurement and Disclosures Level 1 Inputs: Level 2 Inputs: Level 3 Inputs: As of June 30, 2021, the Company had no assets or liabilities measured and recorded at fair value on a recurring basis using Level 3 inputs. Accounts Receivable, Allowance for Expected Credit Losses and Sales Returns Trade accounts receivable do not bear interest and are recorded at the invoiced amount. The Company maintains an allowance for expected credit losses representing its best estimate of expected credit losses related to its existing accounts receivable and their net realizable value. The Company determines the allowance based on a number of factors, including an evaluation of customer credit worthiness, the age of the outstanding receivables, economic trends, historical experience and other information over the payment periods. The Company reviews and adjusts the allowance for expected credit losses on a quarterly basis. Accounts receivable balances are written off against the allowance for expected credit losses when the Company determines that the balances are not recoverable. Provisions for expected credit losses are recorded in “Selling, general and administrative” expenses in the Consolidated Statements of Operations. The Company determines the allowance for sales returns based on its best estimate of expected customer returns. Provisions for sales returns are recorded in "Revenue" in the Consolidated Statements of Operations. The Company does not have any off-balance-sheet credit exposure related to its customers. Leases The Company has operating leases for real estate and non-real estate and finance leases for non-real estate. The classification of a lease as operating or finance and the determination of the right-of-use asset (“ROU asset”) and lease liability are determined at lease inception. The ROU asset represents the Company’s right to use an underlying asset for the lease term and the lease liability represents the Company’s obligation to make lease payments arising from the lease. Operating lease ROU assets and liabilities are recognized at the commencement date of the lease based on the present value of lease payments over the lease term. As most of the Company’s leases do not provide an implicit rate, an incremental borrowing rate is used based on the estimated rate of interest for collateralized borrowing over a similar term of the lease payments at commencement date. Lease terms may include options to extend or terminate the lease when it is reasonably certain that the option will be exercised. Lease expense is recognized on a straight-line basis over the lease term. The Company’s lease agreements may contain lease and non-lease components. Non-lease components primarily include payments for maintenance and utilities. Fixed payments for non-lease components are combined with lease payments and accounted for as a single lease component which increases the amount of the ROU asset and liability. The ROU asset for operating leases is included within “Other assets” and the ROU asset for finance leases is included within “Property, plant, and equipment, net” in the accompanying unaudited Consolidated Balance Sheets. The short-term lease liabilities for both operating leases and finance leases are included within “Accrued expenses and other current liabilities” in the accompanying unaudited Consolidated Balance Sheets. The long-term lease liabilities for operating leases and finance leases are included within “Long-term operating lease liabilities”, and “Other long-term liabilities”, respectively, in the accompanying unaudited Consolidated Balance Sheets. Recently Issued Accounting Pronouncements In October 2020 , the FASB issued Accounting Standards Update (“ASU”) 2020-10, Codification Improvements . The amendments in this ASU represent changes to clarify the ASCs, correct unintended application of guidance, or make minor improvements to the ASC that are not expected to have a significant effect on current accounting practice or create a significant administrative cost to most entities. ASU 2020-10 is effective for annual periods beginning after December 15, 2020 and interim periods within those annual periods, with early adoption permitted. The amendments in this ASU should be applied retrospectively. This ASU will not affect the Company's consolidated financial statements. The Company will adopt the provisions of this ASU in the first quarter of fiscal 2022 and is currently evaluating the impact this guidance may have on the disclosure to the consolidated financial statements. ​ In March 2020 , the FASB issued ASU 2020-04, Facilitation of the Effects of Reference Rate Reform on Financial Reporting . In January 2021, the FASB issued ASU 2021-01 , Reference Rate Reform (Topic 848): Scope . The amendments provide temporary optional expedients and exceptions to the GAAP guidance on contract modifications and hedge accounting to ease the financial reporting burdens related to the expected market transition from the London Interbank Offered Rate (LIBOR) and other interbank offered rates to alternative reference rates. The provisions of the amendments are only available until December 31, 2022, when the reference rate replacement activity is expected to be completed. The Company is currently evaluating the impact this guidance may have on its consolidated financial statements and related disclosures. ​ In December 2019 , the FASB issued ASU 2019-12, Simplifying the Accounting for Income Taxes (Topic 740) , which removes certain exceptions to the general principles in Topic 740 and improves consistent application of and simplifies GAAP for other areas of Topic 740 clarifying and amending existing guidance. This ASU is effective for annual periods, including interim periods within those annual periods, beginning after December 15, 2020. Early adoption is permitted. The Company will adopt the provisions of this ASU in the first quarter of fiscal 2022. The Company is currently evaluating the impact this guidance may have on its consolidated financial statements and related disclosures. ​ In August 2018 , the FASB issued ASU 2018-14, Disclosure Framework — Changes to the Disclosure Requirements for Defined Benefit Plans , which amends ASC 715 to add, remove, and clarify disclosure requirements related to defined benefit pension and other postretirement plans. The amendments require additional disclosure for the weighted-average interest crediting rates, a narrative description of the reasons for significant gains and losses, and an explanation of any other significant changes in the benefit obligation or plan assets. The amendment removes disclosure requirements for accumulated other comprehensive income expected to be recognized over the next year, information about plan assets to be returned to the entity, and the effects of a one-percentage-point change on the assumed health care costs and the effect of this change in rates on service cost, interest cost, and the benefit obligation for postretirement health care benefits. The ASU is effective for fiscal years ending after December 15, 2020. Early adoption is permitted. The ASU does not amend the interim disclosure requirements of ASC 715-20. The Company will adopt the provisions of this ASU in the first quarter of fiscal 2022 and is currently evaluating the impact this guidance may have on the disclosures in the consolidated financial statements. Recently Adopted Accounting Pronouncements In August 2018, the FASB issued ASU 2018-13, Fair Value Measurement (Topic 820): Disclosure Framework - Changes to the Disclosure Requirements for Fair Value Measurement , which amends ASC 820 to add and remove disclosure requirements related to fair value measurement. The amendments include new disclosure requirements for changes in unrealized gains or losses included in other comprehensive income for recurring Level 3 fair value measurements held at the end of the reporting period and the range and weighted average used to develop significant unobservable inputs for Level 3 fair value measurements. The amendments eliminated disclosure requirements for amount of and reasons for transfers between Level 1 and Level 2, valuation processes for Level 3 fair value measurements, and policy for timing of transfers between levels of the fair value hierarchy. In addition, the amendments modified certain disclosure requirements to provide clarification or to promote appropriate exercise of discretion by entities. ASU 2018-13 is effective for fiscal years beginning after December 15, 2019, including interim periods therein. The Company adopted the guidance during the first quarter of fiscal year 2021 . There is no significant accounting impact on the Company’s consolidated financial statements and related disclosures as a result of the adoption of this ASU. In August 2018, the FASB issued ASU 2018-15, Intangibles – Goodwill and Other – Internal-Use Software (Subtopic 350-40): Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract . The amendments align the requirements for capitalizing implementation costs incurred in a hosting arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software (and hosting arrangements that include an internal-use software license). The accounting for the service element of a hosting arrangement that is a service contract is not affected by these amendments. The provisions may be adopted prospectively or retrospectively. This ASU is effective for annual periods, including interim periods within those annual periods, beginning after December 15, 2019. The Company adopted the guidance during the first quarter of fiscal year 2021 on a prospective basis . There is no significant accounting impact on the Company’s consolidated financial statements and related disclosures as a result of the adoption of this ASU. In June 2016, the FASB issued ASU 2016-13, Financial Instruments - Credit Losses: Measurement of Credit Losses on Financial Instruments . The FASB subsequently issued ASU 2019-04, Codification Improvements to Topic 326, Financial Instruments - Credit Losses, Topic 815, Derivatives and Hedging, and Topic 825, Financial Instruments , ASU 2019-05 “Financial Instruments-Credit Losses” , ASU 2019-11, Codification Improvements to Topic 326, Financial Instruments - Credit Losses, and ASU 2020-02 , Financial Instruments-Credit Losses (Topic 326) and Leases (Topic 842) to clarify and address certain items related to the amendments in ASU 2016-13. Topic 326 provides guidance for recognizing credit losses on financial instruments based on an estimate of current expected credit losses model. The amendments are effective for fiscal years, and interim periods within those years, beginning after December 15, 2019. The Company adopted the guidance during the first quarter of fiscal year 2021 . There is no significant accounting impact on the Company’s consolidated financial statements and related disclosures as a result of the adoption of this ASU. Other For further information with regard to the Company’s significant accounting policies, please refer to Note 2 “Summary of Significant Accounting Policies” to the Company’s consolidated financial statements included in the 2020 Annual Report on Form 10-K.

Discontinued Operations

Discontinued Operations	9 Months Ended
	Jun. 30, 2021
Discontinued Operations and Disposal Groups [Abstract]
Discontinued Operations	3. Discontinued Operations On August 27, 2018, the Company entered into a definitive agreement to sell its semiconductor cryogenics business to Edwards for $675.0 million in cash, subject to adjustments. The sale closed on July 1, 2019. The Company completed the sale for $659.8 million. Net proceeds from the sale were approximately $551.7 million, net of taxes and closing costs paid and remaining estimated taxes payable. During the first quarter of fiscal year 2021, the final net working capital was determined and resulted in a negative adjustment in the amount of $1.8 million payable to Edwards, which was paid during the second quarter of the 2021 fiscal year. ​ In the third quarter of fiscal year 2020, Edwards asserted claims for indemnification under the definitive agreement relating to alleged breaches of representations and warranties relating to customer warranty claims and inventory. The Company cannot determine the probability of any losses or outcome of these claims including the amount of any indemnifiable losses, if any, resulting from these claims at this time. The Company believes, however, that none of these claims will have a material adverse effect on its consolidated financial position or results of operations. If the resolution of these claims results in indemnifiable losses in excess of the applicable indemnification deductibles and indemnification escrow established under the definitive agreement, Edwards would be required to seek recovery under the representation and warranty insurance Edwards obtained in connection with the closing of the transaction. The Company believes that any indemnifiable losses in excess of the applicable deductibles and indemnification escrow established in the definitive agreement would be covered by such insurance. If Edwards is unable to obtain recovery under its insurance, however, it could seek recovery of such indemnifiable losses, if any, directly from the Company. The semiconductor cryogenics business consisted of the CTI pump business, Polycold chiller business, the related services business and a 50% share in Ulvac Cryogenics, Inc., a joint venture based in Japan. The semiconductor cryogenics business was originally acquired by the Company in its 2005 merger with Helix Technology Corporation. The operating results of the semiconductor cryogenics business had been included in the Brooks Semiconductor Solutions Group In connection with the closing of the Disposition on July 1, 2019, the Company and Edwards entered into a transition service agreement, a supply agreement, and lease agreements. The transition service agreement outlined the information technology, people, and facility support the parties provided to each other for the period ending 9 months after the transaction closing date. The supply agreement allowed the Company to purchase CTI and Polycold goods at cost from Edwards up to an aggregate amount equal to $1.0 million until the one-year anniversary of closing the Disposition. The lease agreements provide facility space in Chelmsford, Massachusetts to Edwards free of charge for three years after the transaction closing date. Edwards has the option to renew each lease at the then current market rates after the initial three-year lease term has ended. This Disposition was consistent with the Company’s long-standing strategy to increase shareholder value by accelerating the growth of its Life Sciences businesses with further acquisitions and strengthening its semiconductor automation business with opportunistic acquisitions. The Disposition met the "held for sale" criteria and the “discontinued operation” criteria in accordance with FASB ASC 205 as of September 30, 2018. As such, its operating results have been reported as a discontinued operation for all periods presented. The following table presents the financial results of discontinued operations (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended June 30, ​ ​ Nine Months Ended June 30, ​ ​ ​ ​ 2021 2020 ​ ​ 2021 2020 ​ Loss on discontinued operations before income taxes ​ ​ ​ $ (4) ​ $ - ​ ​ $ (1,534) ​ $ (239) ​ Net loss from discontinued operations ​ ​ ​ ​ (4) ​ ​ - ​ ​ ​ (1,168) ​ ​ (182) ​ ​

Marketable Securities

Marketable Securities	9 Months Ended
	Jun. 30, 2021
Investments, Debt and Equity Securities [Abstract]
Marketable Securities	4. Marketable Securities The Company invests in marketable securities that are classified as available-for-sale and records them at fair value in the accompanying unaudited Consolidated Balance Sheets. Marketable securities reported as current assets represent investments that mature within one year from the balance sheet date. Long-term marketable securities represent investments with maturity dates greater than one year from the balance sheet date. The securities are valued using matrix pricing and benchmarking and classified within Level 2 of the fair value hierarchy because they are not actively traded. Matrix pricing is a mathematical technique used to value securities by relying on the securities’ relationship to other benchmark quoted prices. Unrealized gains and losses are excluded from earnings and reported as a separate component of “Total other comprehensive income, net of tax” in the accompanying unaudited Consolidated Statement of Comprehensive Income until the security is sold or matures. Gains or losses realized from sales of marketable securities are computed based on the specific identification method and recognized as a component of "Other income (expenses), net" in the accompanying unaudited Consolidated Statements of Operations. During the nine months ended June 30, 2021, there were insignificant sales of marketable securities. During the nine months ended June 30, 2020, the Company sold marketable securities with a fair value The following is a summary of the amortized cost and the fair value, including accrued interest receivable and unrealized holding gains (losses) on the short-term and long-term marketable securities as of June 30, 2021 and September 30, 2020 (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Gross Gross ​ ​ ​ Amortized ​ Unrealized ​ Unrealized ​ ​ ​ ​ Cost ​ Losses ​ Gains ​ Fair Value June 30, 2021: ​ ​ ​ ​ U.S. Treasury securities and obligations of U.S. government agencies $ 20 ​ $ — ​ $ — $ 20 Bank certificates of deposits ​ ​ 30 ​ ​ — ​ ​ — ​ ​ 30 Corporate securities ​ ​ 3,663 ​ ​ — ​ ​ — ​ ​ 3,663 Municipal securities ​ 25 ​ ​ — ​ ​ — ​ 25 ​ ​ $ 3,738 ​ $ — ​ $ — ​ $ 3,738 September 30, 2020: ​ ​ ​ ​ ​ Bank certificates of deposits ​ $ 51 ​ $ — ​ $ — ​ $ 51 Corporate securities ​ ​ 3,101 ​ ​ — ​ ​ — ​ ​ 3,101 Other debt securities ​ 16 ​ ​ — ​ ​ — ​ 16 ​ ​ $ 3,168 ​ $ — ​ $ — ​ $ 3,168 ​ The fair values of the marketable securities by contractual maturities at June 30, 2021 are presented below (in thousands): ​ ​ ​ ​ ​ Fair Value Due in one year or less ​ $ 101 Due after one year through five years ​ — Due after five years through ten years ​ ​ — Due after ten years ​ 3,637 Total marketable securities ​ $ 3,738 ​ Expected maturities could differ from contractual maturities because the security issuers may have the right to prepay obligations without prepayment penalties. The Company reviews the marketable securities for impairment at each reporting period to determine if any of the securities have experienced an other-than-temporary decline in fair value. The Company considers factors, such as the length of time and extent to which the market value has been less than the cost, the financial condition and near-term prospects of the issuer, the Company’s intent to sell, or whether it is more likely than not it will be required to sell the investment before recovery of its amortized cost basis. If the Company believes that an other-than-temporary decline in fair value has occurred, it writes down the investment to its fair value and recognizes the credit loss in earnings and the non-credit loss in accumulated other comprehensive income or loss. There was an insignificant amount of securities in an unrealized loss position as of June 30, 2021. There were no securities in an unrealized loss position as of September 30, 2020. ​ Cash equivalents of less than $0.1 million at June 30, 2021 consist of money market funds and are classified within Level 1 of the fair value hierarchy because they are valued using quoted market prices in active markets. There were no cash equivalents classified within Level 1 of the fair value hierarchy as of September 30, 2020. Cash equivalents of $0.1 million as of September 30, 2020, consist primarily of treasury bills and agency bonds and are classified within Level 2 of the fair value hierarchy because they are not actively traded. Cash equivalents from Level 1 and Level 2 are recorded in “Cash and cash equivalents” within the accompanying unaudited Consolidated Balance Sheet.

Acquisitions

Acquisitions	9 Months Ended
	Jun. 30, 2021
Business Combinations [Abstract]
Acquisitions	5. Acquisitions Acquisitions Completed in Fiscal Year 2021 Precise On April 29, 2021 , the Company acquired Precise Automation Inc. (“Precise”), a leading developer of collaborative robots and automation subsystems headquartered in Fremont, California. The total cash purchase price for the acquisition was approximately $69.6 million, subject to working capital and other adjustments. Precise provides the Company with a product offering and technology portfolio to take advantage of the opportunities in the collaborative robot market. The allocation of the consideration included $38.9 million of technology, $2.4 million of customer relationships, $32.9 million of goodwill, $6.2 million of deferred tax liabilities, and several other assets and liabilities. The weighted useful life of all the intangible assets acquired is 11 years . The purchase price allocation was based on a preliminary valuation which is subject to further adjustments within the measurement period when additional information becomes available. The Company has included the financial results of the acquired operations in the Brooks Semiconductor Solutions Group segment. The goodwill and intangibles are not tax deductible. Other Acquisitions The Company closed an acquisition during the third quarter of fiscal year 2021. The Company has included the financial results of the acquired operations within the Brooks Life Sciences Products segment. The total net of cash purchase price was approximately $19.3 million which includes $9.4 million in contingent consideration based on the acquired business’ performance for the twelve-month period ending December 31, 2021, subject to customary working capital adjustments and other adjustments. The acquisition enhances the breadth and depth of the Company’s offerings and expands its expertise in the Brooks Life Sciences Products segment. The allocation of the consideration included $11.9 million of technology, $4.4 million of goodwill, and several other assets and liabilities. The weighted useful life of all the intangible assets acquired is 12 years . The purchase price allocation was based on a preliminary valuation which is subject to further adjustments within the measurement period when additional information becomes available. The goodwill and intangibles are tax deductible . On December 3, 2020, the Company acquired Trans-Hit Biomarkers Inc. (“THB”), a worldwide biospecimen procurement service provider based in Montreal Canada. THB has an extensive collection capability for biospecimens and clinical samples through a worldwide partner network of clinical sites and biobanks. The total cash purchase price of the acquisition was approximately $15.1 million, net of cash acquired. The acquisition enhances the breadth and depth of the Company’s offerings and expands its expertise in the Brooks Life Sciences Services segment. The allocation of the consideration included $7.8 million of customer relationships, $9.3 million of goodwill, $2.4 million of deferred tax liabilities, and several other assets and liabilities. The weighted useful life of all intangibles acquired is 11 years . The purchase price allocation was based on a preliminary valuation which is subject to further adjustments within the measurement period when additional information becomes available. The Company has included the financial results of the acquired operations in the Brooks Life Sciences Services segment. The goodwill and intangibles are not tax deductible. Acquisition Completed in Fiscal Year 2020 RURO On February 11, 2020, the Company acquired RURO, Inc. (“RURO”), an informatics software company based in Frederick, Maryland. RURO provides cloud-based software solutions to manage laboratory workflow and bio-sample data for a broad range of customers in the biotech, healthcare, and pharmaceutical sectors. The addition of RURO's capabilities and offerings will enable the Company to offer enhanced on-site and off-site management of biological sample inventories as well as integration solutions to its customers for their increasingly distributed workflow. The total cash purchase price of the acquisition net of cash acquired was $15.2 million after the Company’s agreement with the seller of a net working capital settlement. The Company received $0.5 million in connection with the net working capital settlement on April 1, 2021. The allocation of the consideration primarily included $0.6 million of accounts receivable, $2.9 million of customer relationships, $2.9 million of technology assets, $11.0 million of goodwill, and $2.7 million of liabilities. The goodwill from this acquisition is reported within the Brooks Life Sciences Services segment and is not tax deductible.

Goodwill and Intangible Assets

Goodwill and Intangible Assets	9 Months Ended
	Jun. 30, 2021
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Intangible Assets	6. Goodwill and Intangible Assets Goodwill represents the excess of net book value over the estimated fair value of net tangible and identifiable intangible assets of a reporting unit. Goodwill is tested for impairment annually or more often if impairment indicators are present at the reporting unit level. If events occur or circumstances change that would more likely than not reduce fair values of the reporting units below their carrying values, goodwill will be evaluated for impairment between annual tests. No triggering events indicating goodwill impairment occurred during the nine months ended June 30, 2021. Please refer to Note 8, "Goodwill and Intangible Assets" to the Company's consolidated financial statements included in the 2020 Annual Report on Form 10-K for further information on the goodwill impairment testing performed during fiscal year 2020. The Company performs its annual goodwill impairment assessment on April 1st of each year. In accordance with ASC 350, Intangibles-Goodwill and Other During the quarter ended June 30, 2021, the Company completed the annual goodwill impairment test for each of its reporting units, including the Automation Solutions, Contamination Control Solutions and Global Semiconductor Services reporting units within the Brooks Semiconductor Solutions Group segment, the Brooks Life Sciences Products reporting unit within the Brooks Life Sciences Products segment, and the Sample Repository Solutions and GENEWIZ reporting units within the Brooks Life Sciences Services segment. Based on the test results, the Company determined that no adjustment to goodwill was necessary. The Company conducted a qualitative assessment for the Automation Solutions, Global Semiconductor Services and Life Sciences Products reporting units. The Company determined that it was more likely than not that their fair values were greater than their carrying values. As a result of the analysis, the Company did not perform the quantitative assessment for these reporting units, and therefore, did not As a result of a change in our management reporting structure and immediately post to the annual goodwill impairment test, the Company combined two components within the Brooks Life Sciences Services operating segment, Sample Repository Solutions and GENEWIZ components, into the Brooks Life Sciences Services reporting unit. The Company evaluated the aggregation criteria under ASC 350 for the two components and concluded that they exhibit similar economic characteristics and meet the aggregation criteria. Post to this aggregation, the Company has five reporting units which includes the Automation Solutions, Contamination Control Solutions, Global Semiconductor Services, Brooks Life Sciences Products, and Brooks Life Sciences Services reporting units. The changes in the Company’s goodwill by reportable segment since September 30, 2020 are as follows (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Brooks ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Semiconductor ​ Brooks ​ Brooks ​ ​ ​ ​ ​ ​ ​ Solutions ​ Life Sciences ​ Life Sciences ​ ​ ​ ​ ​ ​ ​ Group ​ Products ​ Services ​ Other ​ Total Gross goodwill, at September 30, 2020 ​ $ 637,303 ​ $ 103,278 ​ $ 349,899 ​ $ 26,014 ​ $ 1,116,494 Accumulated goodwill impairments ​ (588,944) ​ — ​ ​ ​ (26,014) ​ (614,958) Goodwill, net of accumulated impairments, at September 30, 2020 ​ 48,359 ​ 103,278 ​ 349,899 ​ — ​ 501,536 Acquisitions and adjustments ​ 32,911 ​ 7,493 ​ 9,386 ​ — ​ 49,790 Gross goodwill, at June 30, 2021 ​ ​ 670,214 ​ ​ 110,771 ​ ​ 359,285 ​ ​ 26,014 ​ ​ 1,166,284 Accumulated goodwill impairments ​ (588,944) ​ — ​ ​ ​ (26,014) ​ (614,958) Goodwill, net of accumulated impairments, at June 30, 2021 ​ $ 81,270 ​ $ 110,771 ​ $ 359,285 ​ $ — ​ $ 551,326 ​ During the nine months ended June 30, 2021, the Company recorded a goodwill increase of $49.8 million primarily related to acquisitions made during the nine months ended June 30, 2021 and the impact of foreign currency translation adjustments. The components of the Company’s identifiable intangible assets as of June 30, 2021 and September 30, 2020 are as follows (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ June 30, 2021 ​ September 30, 2020 ​ ​ ​ ​ Accumulated ​ Net Book ​ ​ ​ Accumulated ​ Net Book ​ Cost Amortization Value Cost Amortization Value Patents ​ $ 5,302 ​ $ 5,013 ​ $ 289 ​ $ 5,302 ​ $ 4,865 ​ $ 437 Completed technology ​ 144,440 ​ 58,118 ​ 86,323 ​ 92,477 ​ 49,875 ​ 42,602 Trademarks and trade names ​ 27,625 ​ 12,102 ​ 15,523 ​ 25,769 ​ 9,322 ​ 16,447 Non-competition agreements ​ ​ 731 ​ ​ 129 ​ ​ 601 ​ ​ — ​ ​ — ​ ​ — Customer relationships ​ 285,685 ​ 133,488 ​ 152,197 ​ 271,113 ​ 112,277 ​ 158,836 Other intangibles ​ ​ 251 ​ ​ 248 ​ ​ 3 ​ ​ 245 ​ ​ 242 ​ ​ 3 ​ ​ $ 464,034 ​ $ 209,098 ​ $ 254,937 ​ $ 394,906 ​ $ 176,581 ​ $ 218,325 ​ Amortization expense for intangible assets was $30.8 million and $31.3 million, respectively, during the nine months ended June 30, 2021 and 2020. Estimated future amortization expense for the intangible assets for the remainder of fiscal year 2021, the subsequent four fiscal years and thereafter is as follows (in thousands): ​ ​ ​ ​ Fiscal year ended September 30, ​ 2021 ​ $ 10,853 2022 ​ 40,414 2023 ​ 37,125 2024 ​ 32,242 2025 ​ 26,937 Thereafter ​ 107,366 ​ ​ $ 254,937 ​

Line of Credit

Line of Credit	9 Months Ended
	Jun. 30, 2021
Line of Credit
Line of Credit Facility [Line Items]
Line of Credit	7. Line of Credit The Company maintains a revolving line of credit under a credit agreement with Wells Fargo Bank, N.A. and JPMorgan Chase Bank, N.A. that provides for a revolving credit facility of up to $75.0 million, subject to borrowing base availability, as defined in the credit agreement. The line of credit matures on October 4, 2022 and expires no less than 90 days prior to the term loan expiration discussed below. The proceeds from the line of credit are available for permitted acquisitions and general corporate purposes. ​ On October 4, 2017, the Company entered into a $200.0 million Senior Secured Term Loan Facility (the “term loan”) with Morgan Stanley Senior Funding, Inc., JPMorgan Chase Bank, N.A. and Wells Fargo Securities, LLC (collectively, the “lenders”). Coincident with the entry into the credit agreement for the term loan discussed in Note 8, “Debt” below, the Company amended certain terms and conditions of the credit agreement for the line of credit. Based on the amended terms of the credit agreement, the line of credit continues to provide for a revolving credit facility of up to $75.0 million, subject to borrowing base availability. Borrowing base availability under the amended credit agreement excludes collateral related to fixed assets and is redetermined periodically based on certain percentage of certain eligible U.S. assets, including accounts receivable and inventory. The sub-limits for letters of credit were reduced to $7.5 million under the amended terms of the credit agreement. All outstanding borrowings under the credit agreement are guaranteed by the Company and Brooks Life Sciences, Inc. (fka BioStorage Technologies, Inc.), the Company’s wholly-owned subsidiary (“guarantor”), and subordinated to the obligations under the term loan which are secured by a first priority lien on substantially all of the assets of the Company and the guarantor, other than accounts receivable and inventory. Please refer to Note 8, “Debt”, for further information on the term loan transaction. As of June 30, 2021, the Company had approximately $49.8 million available for borrowing under the line of credit. There were no amounts outstanding under the line of credit as of June 30, 2021 and September 30, 2020. The Company records commitment fees and other costs directly associated with obtaining the line of credit facility as deferred financing costs which are amortized over the term of the related financing arrangement. Deferred financing costs were $0.2 million and $0.4 million, respectively, at June 30, 2021 and September 30, 2020. The line of credit contains certain customary representations and warranties, a financial covenant and affirmative and negative covenants as well as events of default. The Company was in compliance with the line of credit covenants as of June 30, 2021.

Debt

Debt	9 Months Ended
	Jun. 30, 2021
Secured Debt
Debt Instrument [Line Items]
Debt	8. Debt Term Loans On October 4, 2017, the Company entered into a $200.0 million term loan with the lenders pursuant to the terms of a credit agreement. The term loan was issued at $197.6 million, or 98.8% of its par value, resulting in a discount of $2.4 million, or 1.2%, which represented loan origination fees paid at the closing. On November 15, 2018, the Company entered into an incremental amendment (the “First Amendment”) to the existing credit agreement. Under the First Amendment, the Company obtained an incremental term loan in an aggregate principal amount of $350.0 million. The proceeds of the incremental term loan were used to finance a portion of the purchase price for the Company’s acquisition of GENEWIZ Group. The incremental term loan was issued at $340.5 million, or 97.3% of its par value, resulting in a discount of $9.5 million, or 2.7%, which represented financing cost of the incremental term loan. Except as provided in the First Amendment, the incremental term loan was subject to the same terms and conditions as set forth in the existing credit agreement. On February 15, 2019, the Company entered into the second amendment to the credit agreement (the “Second Amendment”) and syndicated the incremental term loan to a group of new lenders which met the criteria of a debt extinguishment. The Company wrote off the carrying value of the incremental term loan of $340.1 million as of February 15, 2019 and recorded the syndicated incremental term loan at its present value for $349.1 million and a loss on debt extinguishment for $9.1 million. The syndicated incremental term loan was issued at $345.2 million, or 98.9% of its par value, resulting in a discount of $4.0 million which represented financing costs which are presented as a reduction of the incremental term loan principal balance in the accompanying unaudited Consolidated Balance Sheets and was accreted over the life of the incremental term loan. Except as provided in the Second Amendment with respect to an increase of the applicable interest rates, the syndicated incremental term loan was subject to the same terms and conditions as the initial incremental term loan. On July 1, 2019, the Company completed the sale of its semiconductor cryogenics business and used $348.3 million of the proceeds from the Disposition to extinguish the outstanding balance of the incremental term loan. In addition, the Company used $147.0 million of the proceeds from the Disposition to extinguish a portion of the outstanding balance of the term loan. The Company recorded a loss on debt extinguishment of $5.2 million for the two term loans. The Company’s obligations under the term loan are also guaranteed by Brooks Life Sciences, Inc. (fka BioStorage Technologies, Inc.) as the guarantor, subject to the terms and conditions of the credit agreement. The Company and the guarantor granted the lenders a perfected first priority security interest in substantially all of the assets of the Company and the guarantor to secure the repayment of the term loan. The loan principal amount under the credit agreement may be increased by an aggregate amount equal to $75.0 million plus any voluntary repayments of the term loan plus any additional amount such that the secured leverage ratio of the Company is less than 3.00 to 1.00. Subject to certain conditions stated in the credit agreement, the Company may redeem the term loan at any time at its option without a significant premium or penalty, except for a repricing transaction, as defined in the credit agreement. The Company is required to redeem the term loan at the principal amount then outstanding upon occurrence of certain events, including (i) net proceeds received from the sale or other disposition of the Company’s or the guarantor’s assets, subject to certain limitations, (ii) casualty and condemnation proceeds received by the Company or the guarantor, subject to certain exceptions, or (iii) net proceeds received by the Company or the guarantor from the issuance of debt or disqualified capital stock after October 4, 2017. Commencing on December 31, 2018, the Company was required to make principal payments equal to the excess cash flow amount, as defined in the credit agreement. Such prepayments are equal to 50% of the preceding year excess cash flow amount reduced by voluntary prepayments of the term loan, subject to certain limitations. The deferred financing costs are accreted over the term of the loan using the effective interest rate method and are included in “Interest expense” in the accompanying unaudited Consolidated Statements of Operations. At June 30, 2021, deferred financing costs were $0.3 million. The credit agreement contains certain customary representations and warranties, covenants and events of default. If any of the events of default occur and are not waived or cured within applicable grace periods, any unpaid amounts under the credit agreement will bear an annual interest rate at 2.00% above the rate otherwise applicable under the terms and conditions of such agreement. The credit agreement does not contain financial maintenance covenants. As of June 30, 2021, the Company was in compliance with all covenants and conditions under the credit agreement. In connection with the GENEWIZ acquisition, the Company assumed three five-year term loans for a total of $3.3 million and two one-year short term loans for a total of $3.2 million. The three five-year term loans were initiated during 2016 and matured in 2021. The principal payments were payable in eight installments equal to 12.5% of the initial principal amount of the term loans on December 14th and June 14th of each year. The three five-year term loans were secured by GENEWIZ to fund equipment procurement and new building related payments and the interest rates were equal to the LIBOR plus 3.1%. The two one-year term loans were secured by GENEWIZ to fund operations. Both of the one-year term loans were initiated in 2018 and matured and were repaid in 2019. The interest rates of these two loans were 4.56% and 4.35%. There are no deferred financing costs related to either the five-year term loans or the one-year term loans. The three five-year term loans matured and were repaid in full on June 30, 2021. During the nine months ended June 30, 2021, the weighted average stated interest rate paid on all outstanding debt was 2.8%. During the nine months ended June 30, 2021, the Company incurred aggregate interest expense of $1.3 million in connection with the borrowings, including $0.2 million of deferred financing costs amortization. The following are the future minimum principal payment obligations under all of the Company’s outstanding debt as of June 30, 2021 (in thousands): ​ ​ ​ ​ ​ ​ Amount Fiscal year ended September 30, ​ ​ ​ 2021 ​ $ — 2022 ​ ​ — 2023 ​ ​ — 2024 ​ ​ — 2025 ​ ​ 50,000 Total outstanding principal balance ​ ​ 50,000 Unamortized deferred financing costs ​ ​ (349) ​ ​ ​ 49,651 Current portion of long-term debt ​ ​ — Non-current portion of long-term debt ​ $ 49,651 ​

Leases

Leases	9 Months Ended
	Jun. 30, 2021
Leases [Abstract]
Leases	9. Leases The Company has operating leases for real estate and non-real estate and finance leases for non-real estate in North America, Europe, and Asia. Non-real estate leases are primarily related to vehicles and office equipment. Lease expiration dates range between 2021 and 2041. The components of lease expense were as follows (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended June 30, ​ Nine Months Ended June 30, ​ ​ ​ ​ ​ ​ 2021 ​ 2020 ​ 2021 ​ 2020 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating lease costs ​ ​ ​ $ 2,878 ​ $ 2,358 ​ $ 8,135 ​ $ 6,755 ​ ​ ​ Finance lease costs: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Amortization of assets ​ ​ ​ ​ 182 ​ ​ 311 ​ ​ 745 ​ ​ 933 ​ ​ ​ Interest on lease liabilities ​ ​ ​ ​ 10 ​ ​ 29 ​ ​ 31 ​ ​ 84 ​ ​ ​ Total finance lease costs ​ ​ ​ ​ 192 ​ ​ 340 ​ ​ 776 ​ ​ 1,017 ​ ​ ​ Variable lease costs ​ ​ ​ ​ 514 ​ ​ 448 ​ ​ 1,578 ​ ​ 1,314 ​ ​ ​ Short-term lease costs ​ ​ ​ ​ 123 ​ ​ 181 ​ ​ 349 ​ ​ 477 ​ ​ ​ Total lease costs ​ ​ ​ $ 3,707 ​ $ 3,327 ​ $ 10,838 ​ $ 9,563 ​ ​ ​ ​ Supplemental balance sheet information related to leases is as follows (in thousands, except lease term and discount rate): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ June 30, 2021 ​ September 30, 2020 ​ Operating Leases: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating lease right-of-use assets ​ ​ ​ ​ ​ ​ ​ ​ ​ $ 52,159 ​ $ 39,071 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Accrued expenses and other current liabilities ​ ​ ​ ​ ​ ​ ​ ​ ​ $ 7,489 ​ $ 7,015 ​ Long-term operating lease liabilities ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 45,034 ​ ​ 31,855 ​ Total operating lease liabilities ​ ​ ​ ​ ​ ​ ​ ​ ​ $ 52,523 ​ $ 38,870 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Finance Leases: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Property, plant and equipment, at cost ​ ​ ​ ​ ​ ​ ​ ​ ​ $ 2,252 ​ $ 2,540 ​ Accumulated amortization ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (1,989) ​ ​ (1,246) ​ Property, plant and equipment, net ​ ​ ​ ​ ​ ​ ​ ​ ​ $ 263 ​ $ 1,294 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Accrued expenses and other current liabilities ​ ​ ​ ​ ​ ​ ​ ​ ​ $ 610 ​ $ 1,135 ​ Other long-term liabilities ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (10) ​ ​ 348 ​ Total finance lease liabilities ​ ​ ​ ​ ​ ​ ​ ​ ​ $ 600 ​ $ 1,483 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted average remaining lease term (in years): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating leases ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 10.73 ​ ​ 8.72 ​ Finance leases ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 0.71 ​ ​ 1.32 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted average discount rate: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating leases ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 4.02 % ​ 3.92 % Finance leases ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 4.81 % ​ 4.73 % ​ Supplemental cash flow information related to leases was as follows (in thousands, unaudited): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended June 30, ​ Nine Months Ended June 30, ​ ​ ​ ​ ​ ​ 2021 ​ 2020 ​ 2021 ​ 2020 ​ ​ ​ Cash paid for amounts included in measurement of liabilities: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating cash flows from operating leases ​ ​ ​ $ 2,532 ​ $ 2,215 ​ $ 7,530 ​ $ 6,089 ​ ​ ​ Operating cash flows from finance leases ​ ​ ​ ​ 8 ​ ​ 22 ​ ​ 35 ​ ​ 77 ​ ​ ​ Financing cash flows from finance leases ​ ​ ​ ​ 269 ​ ​ 297 ​ ​ 881 ​ ​ 880 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ROU assets obtained in exchange for lease liabilities: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating leases ​ ​ ​ $ 14,066 ​ $ 3,026 ​ $ 19,033 ​ $ 13,753 ​ ​ ​ ​ ​ Future lease payments for operating and finance leases as of June 30, 2021 were as follows for the remainder of fiscal year 2021, the subsequent four fiscal years and thereafter (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating Leases ​ Finance Leases ​ ​ Fiscal year ended September 30, ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 2021 ​ ​ ​ ​ ​ ​ ​ ​ ​ $ 2,501 ​ $ 251 ​ ​ ​ 2022 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 9,032 ​ ​ 363 ​ ​ ​ 2023 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 7,286 ​ ​ - ​ ​ ​ 2024 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 6,378 ​ ​ - ​ ​ ​ 2025 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 5,779 ​ ​ - ​ ​ ​ Thereafter ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 34,475 ​ ​ - ​ ​ ​ Total future lease payments ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 65,451 ​ ​ 614 ​ ​ ​ Less imputed interest ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (12,928) ​ ​ (14) ​ ​ ​ Total lease liability balance ​ ​ ​ ​ ​ ​ ​ ​ ​ $ 52,523 ​ $ 600 ​ ​ ​ ​ ​ As of June 30, 2021, the Company has entered into leases that have not commenced with future lease payments of $15.1 million. These leases are not yet recorded in the accompanying unaudited Consolidated Balance Sheets. These leases will commence in 2021.

Income Taxes

Income Taxes	9 Months Ended
	Jun. 30, 2021
Income Tax Disclosure [Abstract]
Income Taxes	10. Income Taxes The Company recorded an income tax provision of $9.4 million and $20.4 million, respectively, during the three and nine months ended June 30, 2021. The tax provision for the three months ended June 30, 2021 was primarily driven by the provision on earnings from operations during the period. The provision was partially offset by a $1.5 million benefit from the reversal of uncertain tax positions during the period. The provision for the nine months ended June 30, 2021 was primarily driven by the provision on earnings from operations during the period and was partially offset by a The Company recorded an income tax provision of $5.1 million and $5.6 million, respectively, during the three and nine months ended June 30, 2020. The tax provision for the three months ended June 30, 2020 was primarily driven by the provision on earnings from operations during the period. The tax provision for the nine months ended June 30, 2020 was primarily driven by the provision on earnings from operations during the period. The tax provision was offset by a $6.1 million discrete stock compensation windfall benefit for tax deductions that exceeded the associated compensation expense in the period. During the nine months ended June 30, 2020, the Company also recorded a discrete benefit of $0.5 million from a reduction of deferred tax liabilities related to the extension of a tax rate incentive in China. During March 2020, the United States enacted the Coronavirus Aid, Relief, and Economic Security Act which contains numerous income tax provisions among other tax and non-tax provisions. Some of these income tax provisions have retroactive effects on years before the date of enactment. During December 2020, the United States enacted the Consolidated Appropriations Act 2021 which also contains numerous income tax provisions among other tax and non-tax provisions. During March 2021, the United States enacted the American Rescue Plan Act of 2021. The Company evaluated the legislation of all three Acts in relation to income taxes and determined that the income tax Acts do not have a material impact on its income tax provision. The Company evaluates the realizability of its deferred tax assets by tax-paying component and assesses the need for a valuation allowance on a quarterly basis. The Company evaluates the profitability of each tax-paying component on a historic cumulative basis and a forward-looking basis while performing this analysis. The Company maintains a U.S. valuation allowance related to the realizability of certain state tax credits and state net operating loss carry-forwards, as well as a valuation allowance against net deferred tax assets on certain foreign tax-paying components as of June 30, 2021. The Company maintains liabilities for uncertain tax positions. These liabilities involve judgment and estimation and are monitored based on the best information available. The Company recognizes interest related to unrecognized tax benefits as a component of the income tax provision or benefit. The Company recognized interest expense related to its uncertain tax positions of $0.3 million and $0.8 million, respectively, during the three and nine months ended June 30, 2021. The Company is subject to U.S. federal, state, local and foreign income taxes in various jurisdictions. The amount of income taxes paid is subject to the Company’s interpretation of applicable tax laws in the jurisdictions in which it files. In the normal course of business, the Company is subject to income tax audits in various global jurisdictions in which it operates. The years subject to examination vary for the U.S. and international jurisdictions, with the earliest tax year being 2013. Based on the outcome of these examinations or the expiration of statutes of limitations for specific jurisdictions, it is reasonably possible that the related unrecognized tax benefits could change from those recorded in the Company’s Consolidated Balance Sheets. The Company currently anticipates that it is reasonably possible that the unrecognized tax benefits and accrued interest on those benefits will be reduced by an amount of $17.2 million in the next 12 months due to statute of limitations expirations. These unrecognized tax benefits would impact the effective tax rate if recognized.

Other Balance Sheet Information

Other Balance Sheet Information	9 Months Ended
	Jun. 30, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Other Balance Sheet Information	11. Other Balance Sheet Information The following is a summary of accounts receivable at June 30, 2021 and September 30, 2020 (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ June 30, ​ September 30, ​ ​ 2021 2020 Accounts receivable ​ $ 238,890 ​ $ 195,587 ​ Less allowance for expected credit losses ​ (4,737) ​ (7,216) ​ Less allowance for sales returns ​ (74) ​ (80) ​ Accounts receivable, net ​ $ 234,079 ​ $ 188,291 ​ ​ The decrease in the allowance for expected credit losses from September 30, 2020 is due to collections of previously reserved trade receivables in the Brooks Life Sciences Services segment during the first quarter of fiscal year 2021. The following is a summary of inventories at June 30, 2021 and September 30, 2020 (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ June 30, ​ September 30, ​ ​ 2021 2020 Inventories ​ ​ ​ Raw materials and purchased parts ​ $ 98,997 ​ $ 73,609 ​ Work-in-process ​ 21,356 ​ 16,461 ​ Finished goods ​ 34,367 ​ 24,764 ​ Total inventories ​ $ 154,720 ​ $ 114,834 ​ ​ Reserves for excess and obsolete inventory were $18.6 million and $17.1 million, respectively, at June 30, 2021 and September 30, 2020. At June 30, 2021 and September 30, 2020, the Company had cumulative capitalized direct costs of $21.9 million and $18.2 million, respectively, associated with the development of software for its internal use. As of June 30, 2021, this balance included $5.0 million associated with software still in the development stage which are included within "Property, plant and equipment, net" in the accompanying unaudited Consolidated Balance Sheets. During the nine months ended June 30, 2021, the Company capitalized direct costs of $3.7 million associated with the development of software for its internal use. The Company establishes reserves for estimated costs of product warranties based on historical information. Product warranty reserves are recorded at the time product revenue is recognized, and retrofit accruals are recorded at the time retrofit programs are established. The Company’s warranty obligation is affected by product failure rates, utilization levels, material usage, service delivery costs incurred in correcting a product failure and supplier warranties on parts delivered to the Company. The following is a summary of product warranty and retrofit activity on a gross basis for the three and nine months ended June 30, 2021 and 2020 (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Activity -Three Months Ended June 30, 2021 Balance ​ ​ ​ ​ Balance March 31, ​ ​ ​ ​ ​ ​ ​ June 30, 2021 ​ Accruals ​ Costs Incurred ​ 2021 $ 8,044 ​ $ 1,892 ​ $ (1,804) ​ $ 8,132 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Activity -Three Months Ended June 30, 2020 Balance ​ ​ ​ ​ Balance March 31, ​ ​ ​ ​ ​ ​ ​ June 30, 2020 ​ Accruals ​ Costs Incurred ​ 2020 $ 7,910 ​ $ 1,380 ​ $ (1,409) ​ $ 7,881 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Activity -Nine Months Ended June 30, 2021 Balance ​ ​ ​ ​ Balance September 30, ​ ​ ​ ​ ​ ​ ​ June 30, 2020 ​ Accruals ​ Costs Incurred ​ 2021 $ 8,201 ​ $ 5,990 ​ $ (6,059) ​ $ 8,132 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Activity -Nine Months Ended June 30, 2020 Balance ​ ​ ​ ​ Balance September 30, ​ ​ ​ ​ ​ ​ ​ June 30, 2019 ​ Accruals ​ Costs Incurred ​ 2020 $ 7,175 ​ $ 6,033 ​ $ (5,327) ​ $ 7,881 ​

Stock-Based Compensation

Stock-Based Compensation	9 Months Ended
	Jun. 30, 2021
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock-Based Compensation	12. Stock-Based Compensation The Company may issue to eligible employees options to purchase shares of the Company’s stock, restricted stock and other equity incentives which vest upon the satisfaction of a performance condition and/or a service condition. In addition, the Company issues shares to participating employees pursuant to an employee stock purchase plan, and stock awards and deferred restricted stock units to its directors in accordance with its director compensation program. The following table reflects stock-based compensation expense recorded during the three and nine months ended June 30, 2021 and 2020 (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended June 30, ​ Nine Months Ended June 30, ​ ​ 2021 2020 2021 2020 Restricted stock units ​ $ 5,475 ​ $ 3,348 ​ $ 18,667 ​ $ 11,361 ​ Employee stock purchase plan ​ 611 ​ 377 ​ 1,610 ​ 987 ​ Total stock-based compensation expense ​ $ 6,086 ​ $ 3,725 ​ $ 20,277 ​ $ 12,348 ​ ​ The fair value of restricted stock units is determined based on the number of shares granted and the closing price of the Company’s common stock quoted on the Nasdaq Stock Market on the date of grant. For awards that vest based on service conditions, the Company recognizes stock-based compensation expense on a straight-line basis over the requisite service period. For awards that vest subject to performance conditions, the Company recognizes stock-based compensation expense ratably over the performance period if it is probable that performance condition will be met and adjusted for the probability percentage of achieving the performance goals. The Company makes estimates of stock award forfeitures and the number of awards expected to vest. The Company considers many factors in developing forfeiture estimates, including award types, employee classes and historical experience. Each quarter, the Company assesses the probability of achieving the performance goals. Current estimates may differ from actual results and future changes in estimates. The Company grants restricted stock units that vest over a required service period and/or achievement of certain operating performance goals. Restricted stock units granted with performance goals may also have a required service period following the achievement of all or a portion of the performance goals. The following table reflects restricted stock units, including stock awards, granted during the nine months ended June 30, 2021 and 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Time-Based Stock Performance- ​ ​ Total Units ​ Units ​ Grants ​ Based Units Nine months ended June 30, 2021 346,172 162,842 14,683 168,647 Nine months ended June 30, 2020 411,967 163,390 27,007 221,570 ​ Time-Based Grants Restricted stock units granted with a required service period typically have three-year vesting schedules in which one-third one-third one-third Stock Grants The stock awards granted to the members of the Company’s Board of Directors include stock awards and deferred restricted stock units. Certain members of the Board of Directors have elected to defer receiving their annual stock awards and related quarterly dividends until they attain a certain age or cease to provide services as the Company’s Board members. Stock awards granted in fiscal years 2021 and 2020 were vested as of the respective grant dates. Performance-Based Grants Performance-based restricted stock units are earned based on the achievement of performance criteria established by the Human Resources and Compensation Committee and approved by the Board of Directors. The criteria for performance-based awards are weighted and have threshold, target and maximum performance goals. Performance-based awards granted in fiscal year 2021, 2020 and 2019 allow participants to earn 100% of the restricted stock units if the Company’s performance meets its target goal for each applicable financial metric, and up to a maximum of 200% if the Company’s performance for such metrics meets or exceeds the maximum or stretch goal. Performance below the minimum threshold for each financial metric results in award forfeiture. Performance goals will be measured over a three-year period for each year’s awards and at the end of the period to determine the number of units earned by recipients who continue to meet the service requirement. Around the third anniversary of each year’s awards’ grant date, the Company’s Board of Directors determines the number of units earned for participants who continue to meet the service requirements on the vest date. Restricted Stock Unit Activity The following table summarizes restricted stock unit activity for the nine months ended June 30, 2021: ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ ​ ​ ​ Average ​ ​ ​ ​ Grant-Date ​ ​ Shares ​ Fair Value Outstanding at September 30, 2020 1,183,009 ​ $ 36.10 Granted 346,172 ​ ​ 71.81 Vested (406,764) ​ ​ 36.01 Forfeited (32,600) ​ ​ 44.27 Outstanding at June 30, 2021 1,089,817 ​ ​ 47.23 ​ The weighted average grant date fair value of restricted stock units granted during the three months ended June 30, 2021 and 2020 was $104.54 and $31.87, respectively. The weighted average grant date fair value of restricted stock units granted during the nine months ended June 30, 2021 and 2020 was $71.81 and $46.52, respectively. The fair value of restricted stock units vested during the three months ended June 30, 2021 and 2020 was $0.3 million and $0.2 million, respectively. The fair value of restricted stock units vested during the nine months ended June 30, 2021 and 2020 was $28.2 million and $41.6 million, respectively. During the nine months ended June 30, 2021 and 2020, the Company remitted $9.7 million and $24.1 million, respectively, collected from employees to satisfy their tax obligations as a result of share issuances. Such proceeds collected and remitted were insignificant during the three months ended June 30, 2021 and 2020. As of June 30, 2021, the unrecognized compensation cost related to restricted stock units that are expected to vest is $29.1 million and will be recognized over an estimated weighted average service period of approximately 1.7 years. Employee Stock Purchase Plan The Company maintains an employee stock purchase plan that allows its employees to purchase shares of common stock at a price equal to 85% of the fair market value of the Company’s stock at the beginning or the end of the semi-annual offering period, whichever is lower. There were 58,124 and 63,934 shares, respectively, purchased by employees under the employee stock purchase plan during the nine months ended June 30, 2021 and 2020.

Earnings per Share

Earnings per Share	9 Months Ended
	Jun. 30, 2021
Earnings Per Share [Abstract]
Earnings per Share	13. Earnings per Share The calculations of basic and diluted net income per share and basic and diluted weighted average shares outstanding are as follows for the three and nine months ended June 30, 2021 and 2020 (in thousands, except per share data): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ Nine Months Ended ​ ​ ​ June 30, ​ June 30, ​ ​ 2021 2020 2021 2020 Income from continuing operations ​ $ 39,170 ​ $ 13,696 ​ $ 90,110 ​ $ 36,062 ​ Loss from discontinued operations, net of tax ​ (4) ​ — ​ (1,168) ​ (182) ​ Net income ​ $ 39,166 ​ $ 13,696 ​ $ 88,942 ​ $ 35,880 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted average common shares outstanding used in computing basic earnings per share ​ 74,296 ​ 73,759 ​ 74,195 ​ 73,473 ​ Dilutive restricted stock units ​ 199 ​ 101 ​ 225 ​ 293 ​ Weighted average common shares outstanding used in computing diluted earnings per share ​ 74,495 ​ 73,860 ​ 74,420 ​ 73,766 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Basic net income per share: ​ ​ ​ ​ ​ Income from continuing operations ​ $ 0.53 ​ $ 0.19 ​ $ 1.21 ​ $ 0.49 ​ Loss from discontinued operations, net of tax ​ (0.00) ​ - ​ (0.02) ​ (0.00) ​ Basic net income per share ​ $ 0.53 ​ $ 0.19 ​ $ 1.20 ​ $ 0.49 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Diluted net income per share: ​ ​ ​ ​ ​ Income from continuing operations ​ $ 0.53 ​ $ 0.19 ​ $ 1.21 ​ $ 0.49 ​ Loss from discontinued operations, net of tax ​ (0.00) ​ — ​ (0.02) ​ (0.00) ​ Diluted net income per share ​ $ 0.53 ​ $ 0.19 ​ $ 1.20 ​ $ 0.49 ​ Dividend declared per share ​ $ 0.10 ​ $ 0.10 ​ $ 0.30 ​ $ 0.30 ​ ​ During the three and nine months ended June 30, 2021, restricted stock units of 13,593 and 18,548, respectively, were excluded from the computation of diluted earnings per share as their effect would be antidilutive based on the treasury stock method. During the three and nine months ended June 30, 2020, restricted stock units of 148,085 and 162,189, respectively, were excluded from the computation of diluted earnings per share as their effect would be antidilutive based on the treasury stock method.

Revenue from Contracts with Cus

Revenue from Contracts with Customers	9 Months Ended
	Jun. 30, 2021
Revenue from Contract with Customer [Abstract]
Revenue from Contracts with Customers	14. Revenue from Contracts with Customers Disaggregated Revenue The Company disaggregates revenue from contracts with customers in a manner that depicts how the nature, amount, timing, and uncertainty of revenue and cash flows are affected by economic factors. ​ The Company has three operating and reportable segments consisting of Brooks Semiconductor Solutions Group, Brooks Life Sciences Products and Brooks Life Sciences Services. The Company has five reporting units, including three reporting units within the Brooks Semiconductor Solutions Group operating segment, one reporting unit within Brooks Life Sciences Products operating segment, and one reporting units within the Brooks Life Sciences Services operating segment . The following is revenue by reporting unit for the three and nine months ended June 30, 2021 and 2020 (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three months ended June 30, ​ Nine months ended June 30, ​ ​ ​ 2021 ​ 2020 ​ 2021 ​ 2020 Reporting Unit ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Automation Solutions ​ ​ $ 122,567 ​ $ 81,656 ​ $ 320,540 ​ $ 214,627 Contamination Control Solutions ​ ​ ​ 50,742 ​ ​ 34,780 ​ ​ 117,236 ​ ​ 124,584 Global Semiconductor Services ​ ​ ​ 12,953 ​ ​ 10,616 ​ ​ 36,898 ​ ​ 31,575 Total Brooks Semiconductor Solutions Group ​ ​ ​ 186,262 ​ ​ 127,052 ​ ​ 474,674 ​ ​ 370,786 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Brooks Life Sciences Products ​ ​ ​ 48,625 ​ ​ 30,421 ​ ​ 146,490 ​ ​ 91,138 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Brooks Life Sciences Services ​ ​ ​ 80,462 ​ ​ 62,877 ​ ​ 230,275 ​ ​ 189,153 Total ​ ​ $ 315,349 ​ $ 220,350 ​ $ 851,439 ​ $ 651,077 ​ ​ Contract Balances Accounts Receivable, Net. Contract Assets. ​ Deferred Commissions. ​ Contract Liabilities. ​ Remaining Performance Obligations. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of June 30, 2021 ​ ​ ​ ​ ​ Less than 1 Year ​ Greater than 1 Year ​ Total Remaining Performance Obligations ​ ​ ​ ​ $ 46,552 ​ $ 18,677 ​ $ 65,229 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Cost to Obtain and Fulfill a Contract The Company capitalizes sales commissions when incurred if they are (i) incremental costs of obtaining a contract, (ii) expected to be recovered and (iii) have an expected amortization period that is greater than one year. As part of the Company’s cumulative effect adjustment, incremental costs associated with obtaining a contract were capitalized and have been classified as deferred commissions within the Company’s Consolidated Balance Sheet. These amounts primarily relate to sales commissions within the Brooks life sciences segments and are being amortized over a 60-month period, which represents the average period of contract performance. The Company did not capitalize any sales commissions during the three and nine months ended June 30, 2021 as the amount of sales commissions that qualified for capitalization during the reporting period was insignificant. Sales commissions incurred during the reporting period have been expensed as incurred. These costs are recorded within “Selling, general and administrative” expenses on the Company’s Consolidated Statement of Operations. The Company has concluded that none of its costs incurred in fulfillment of customer contracts meet the capitalization criteria. The Company will account for shipping and handling activities as fulfillment activities and recognize the associated expense when control of the product has transferred to the customer.

Segment Information

Segment Information	9 Months Ended
	Jun. 30, 2021
Segment Reporting [Abstract]
Segment Information	15. Segment Information Operating segments are defined as components of an enterprise that engage in business activities for which discrete financial information is available and regularly reviewed by the chief operating decision maker in deciding how to allocate resources and to assess performance. The Company’s Chief Executive Officer is the Company’s chief operating decision maker. The Company operates in three reportable segments: the Brooks Semiconductor Solutions Group segment, the Brooks Life Sciences Products segment and the Brooks Life Sciences Services segment. These reportable segments also represent the Company’s operating segments. The Company previously operated in two reportable segments: the Brooks Semiconductor Solutions Group segment and the Brooks Life Sciences segment. The Brooks Life Sciences segment consisted of the Sample Management operating segment and the GENEWIZ operating segment that aggregated into one reportable segment. During fiscal year 2020, the Company reorganized its operating segments to better align with its business activities in connection with its recent acquisitions and the Company’s strategic vision. Historical information has been adjusted to reflect the new reportable segments. The Brooks Semiconductor Solutions Group segment provides a variety of products, services and solutions that enable improved throughput and yield in controlled operating environments, as well as an extensive range of support services. The solutions include atmospheric and vacuum robots, robotic modules, tool automation systems, contamination control of carrier pods and reticle storage. The support services include repair services, diagnostic support services, and installation services in support of the products, which enable customers to maximize process tool uptime and productivity. This segment also provides end-user customers with spare parts and enhancement upgrades to maximize tool productivity. The Brooks Life Sciences Products segment provides automated cold sample management systems for compound and biological sample storage, equipment for sample preparation and handling, consumables and instruments, that help customers manage samples throughout their research discovery and development workflows. The segment’s product offerings include automated cold storage systems, cryogenic storage systems, consumables and instruments and the associated services business for these products. The Brooks Life Sciences Services segment provides comprehensive sample management programs, integrated cold chain solutions, informatics, as well as sample-based laboratory services to advance scientific research and support drug development. The segment’s service offerings include sample storage, genomic sequencing, gene synthesis, laboratory processing services, laboratory analysis, and other support services which are provided to a wide range of life science customers, including pharmaceutical companies, biotechnology companies, biorepositories and research institutes. The Company considers adjusted operating income, which excludes charges related to amortization of completed technology, the acquisition accounting impact on inventory contracts acquired and restructuring related charges as the primary performance metric when evaluating the business. The following is the summary of the financial information for the Company’s reportable segments for the three and nine months ended June 30, 2021 and 2020 (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended June 30, ​ ​ Nine Months Ended June 30, ​ ​ ​ 2021 ​ 2020 ​ 2021 ​ 2020 ​ Revenue: ​ ​ ​ ​ ​ ​ ​ ​ Brooks Semiconductor Solutions Group ​ $ 186,262 ​ $ 127,052 ​ $ 474,674 ​ $ 370,786 ​ Brooks Life Sciences Products ​ ​ 48,625 ​ ​ 30,421 ​ ​ 146,490 ​ ​ 91,138 ​ Brooks Life Sciences Services ​ 80,462 ​ 62,877 ​ 230,275 ​ 189,153 ​ Total revenue ​ $ 315,349 ​ $ 220,350 ​ $ 851,439 ​ $ 651,077 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating income: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Brooks Semiconductor Solutions Group ​ $ 44,797 ​ $ 23,414 ​ $ 99,637 ​ $ 55,120 ​ Brooks Life Sciences Products ​ ​ 9,138 ​ ​ 2,482 ​ ​ 28,295 ​ ​ 4,988 ​ Brooks Life Sciences Services ​ 13,783 ​ 4,109 ​ 41,501 ​ 15,695 ​ Reportable segment adjusted operating income ​ ​ 67,718 ​ ​ 30,005 ​ ​ 169,433 ​ ​ 75,803 ​ Amortization of completed technology ​ ​ 3,352 ​ ​ 2,779 ​ ​ 8,060 ​ ​ 8,194 ​ Amortization of other intangible assets ​ ​ 7,733 ​ ​ 7,611 ​ ​ 22,690 ​ ​ 23,137 ​ Restructuring charges ​ ​ — ​ ​ (29) ​ ​ 179 ​ ​ 1,125 ​ Tariff adjustment ​ ​ — ​ ​ — ​ ​ 5,414 ​ ​ — ​ Other unallocated corporate expenses (income) ​ ​ 6,400 ​ ​ 545 ​ ​ 21,423 ​ ​ (990) ​ Total operating income ​ ​ 50,233 ​ ​ 19,099 ​ ​ 111,667 ​ ​ 44,337 ​ Interest income ​ ​ 409 ​ ​ 29 ​ ​ 503 ​ ​ 865 ​ Interest expense ​ ​ (477) ​ ​ (810) ​ ​ (1,485) ​ ​ (2,265) ​ Other income (expenses), net ​ ​ (1,625) ​ ​ 498 ​ ​ (147) ​ ​ (1,318) ​ Income before income taxes ​ $ 48,540 ​ $ 18,816 ​ $ 110,538 ​ $ 41,619 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Brooks ​ ​ ​ ​ ​ ​ ​ ​ Semiconductor ​ Brooks Life ​ Brooks Life ​ ​ ​ Assets: ​ ​ Solutions Group ​ Sciences Products ​ Sciences Services ​ Total ​ June 30, 2021 ​ $ 433,108 ​ $ 259,592 ​ $ 779,798 ​ $ 1,472,498 ​ September 30, 2020 ​ ​ 296,289 ​ 214,196 ​ ​ 737,967 ​ 1,248,452 ​ ​ ​ The following is a reconciliation of the Company’s reportable segments’ segment assets to the corresponding amounts presented in the accompanying unaudited Consolidated Balance Sheets as of June 30, 2021 and September 30, 2020 (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ June 30, September 30, ​ ​ 2021 ​ 2020 Segment assets $ 1,472,498 $ 1,248,452 Cash and cash equivalents, restricted cash, and marketable securities ​ 286,310 ​ 305,694 Deferred tax assets ​ 4,447 ​ 4,979 Total assets ​ $ 1,763,255 ​ $ 1,559,125 ​ Revenue from external customers is attributed to geographic areas based on locations in which customer orders are placed. Net revenue by geographic area for the three and nine months ended June 30, 2021 and 2020 (in thousands) are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended June 30, ​ ​ Nine Months Ended June 30, ​ 2021 ​ 2020 ​ 2021 ​ 2020 Geographic Location: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Asia / Pacific/ Other ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ China ​ $ 55,062 ​ $ 30,228 ​ $ 137,945 ​ $ 76,435 Taiwan ​ ​ 29,844 ​ ​ 15,266 ​ ​ 73,350 ​ ​ 91,993 Republic of Korea ​ ​ 28,994 ​ ​ 22,369 ​ ​ 77,982 ​ ​ 46,296 Other ​ ​ 37,186 ​ ​ 31,552 ​ ​ 105,861 ​ ​ 93,245 ​ ​ ​ 151,086 ​ ​ 99,415 ​ ​ 395,138 ​ ​ 307,969 North America ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ USA ​ ​ 108,344 ​ ​ 79,032 ​ ​ 290,883 ​ ​ 243,883 Other ​ ​ 2,110 ​ ​ 850 ​ ​ 22,947 ​ ​ 2,117 ​ ​ ​ 110,454 ​ ​ 79,882 ​ ​ 313,830 ​ ​ 246,000 Europe ​ ​ 53,809 ​ ​ 41,053 ​ ​ 142,471 ​ ​ 97,108 Total ​ $ 315,349 ​ $ 220,350 ​ $ 851,439 ​ $ 651,077 ​ ​ The geographic location of an OEM is not indicative of where the products will eventually be used. The geographic area for the orders is determined by the onward sale of an OEM system which incorporates the sub-systems and/or components. ​ ​ ​ ​ ​ ​ ​

Significant Customers

Significant Customers	9 Months Ended
	Jun. 30, 2021
Risks and Uncertainties [Abstract]
Significant Customers	16. Significant Customers The Company had no individual customer that accounted for 10% or more of its consolidated revenue during the three and nine months ended June 30, 2021. The Company had no individual customer that accounted for 10% or more of its consolidated revenue during the three months ended June 30, 2020.

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Jun. 30, 2021
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	17. Commitments and Contingencies GENEWIZ Tariff Matter As part of the Company’s continued integration of GENEWIZ, which was acquired in November 2018, the Company initiated a review, with the assistance of a third party consultant, of the transaction value that the Company has used to calculate tariffs on inter-company imports of samples shipped from its GENEWIZ business. As a result of the third-party review and in light of a new interpretation surrounding the valuation method used to calculate the estimated transaction value, the Company revised its estimate of the tariffs owed and as a result recorded a liability of $6.1 million in the second quarter of 2021. Of the total liability, $2.8 million is for the period prior to the acquisition of GENEWIZ and an additional $3.3 million is for the period since the Company acquired GENEWIZ in November 2018. The Company intends to pay any tariffs determined to be owed. The Company does not expect to incur any significant penalties associated with such tariffs. As a result of the change in estimate, basic net income per share decreased $0.07 for the nine months ended June 30, 2021. Diluted net income per share also decreased $0.07 for the same period. Letters of Credit As of June 30, 2021, the Company had approximately $1.3 million of letters of credit outstanding related primarily to customer advances and other performance obligations. These arrangements guarantee the refund of advance payments received from the Company’s customers in the event that the product is not delivered, or warranty obligations are not fulfilled in accordance with the contract terms. These obligations could be called by the beneficiaries at any time before the expiration date of the particular letter of credit if the Company fails to meet certain contractual requirements. None of these obligations were called during the nine months ended June 30, 2021, and the Company currently does not anticipate any of these obligations to be called in the near future. Purchase Commitments At June 30, 2021, the Company had non-cancellable commitments of $288.0 million, including primarily purchase orders for inventory of $254.6 million, information technology related commitments of $18.0 million, and China facility commitments of $15.2 million. Contingencies The Company is subject to various legal proceedings, both asserted and unasserted, that arise in the ordinary course of business. The Company cannot predict the ultimate outcome of such legal proceedings or in certain instances provide reasonable ranges of potential losses. The Company may also have certain indemnification obligations pursuant to claims made under the definitive agreement it entered into with Edwards in connection with the Company’s sale of its semiconductor cryogenics business. See Note 3 “Discontinued Operations” for further information. However, as of the date of this report, the Company believes that none of these claims will have a material adverse effect on its consolidated financial position or results of operations. In the event of unexpected subsequent developments and given the inherent unpredictability of these matters, there can be no assurance that the Company’s assessment of any claim will reflect the ultimate outcome, and an adverse outcome in certain matters could, from time to time, have a material adverse effect on the Company’s consolidated financial position or results of operations in particular quarterly or annual periods.

Subsequent Events

Subsequent Events	9 Months Ended
	Jun. 30, 2021
Subsequent Events [Abstract]
Subsequent Events	18. Subsequent Events Dividend On August 3, 2021, the Company’s Board of Directors declared a cash dividend of $0.10 per share payable on September 24, 2021 to common stockholders of record as of September 3, 2021. Dividends are declared at the discretion of the Company’s Board of Directors and depend on the Company’s actual cash flows from operations, its financial condition and capital requirements and any other factors the Company’s Board of Directors may consider relevant. Future dividend declarations, as well as the record and payment dates for such dividends, will be determined by the Company’s Board of Directors on a quarterly basis.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	9 Months Ended
	Jun. 30, 2021
Accounting Policies [Abstract]
Use of Estimates	Use of Estimates The preparation of unaudited consolidated financial statements in conformity with GAAP requires management to make certain estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the unaudited consolidated financial statements and the reported amounts of revenue and expenses during the reporting period. Significant estimates are associated with recording accounts receivable, inventories, goodwill, intangible assets other than goodwill, long-lived assets, derivative financial instruments, deferred income taxes, warranty obligations, revenue recognized in accordance with the percentage of completion method, and stock-based compensation expense. The Company bases its estimates on historical experience and various other assumptions, including in certain circumstances future projections that management believes to be reasonable under the circumstances. Although the Company regularly assesses these estimates, actual results could differ from those estimates. Changes in estimates are recorded in the period in which they occur and become known. The full extent to which the COVID-19 pandemic will directly or indirectly impact the Company’s business, including results of operations and financial condition, sales, expenses, reserves and allowances, manufacturing and employee-related amounts, will depend on future developments that are highly uncertain. This includes results from new information that may emerge concerning COVID-19 and any actions taken to contain or treat COVID-19, as well as the economic impact on local, regional, national and international customers and markets. The Company has made estimates of the impact of COVID-19 within its financial statements and there may be changes to those estimates in future periods.
Foreign Currency Translation	Foreign Currency Translation Certain transactions of the Company and its subsidiaries are denominated in currencies other than their functional currency. Foreign currency exchange gains and losses generated from the settlement and remeasurement of these transactions are recognized in earnings and presented within “Other income (expenses), net” in the Company’s unaudited Consolidated Statements of Operations. Net foreign currency transaction and remeasurement losses were $1.6 million and less than $0.1 million during the three months ended June 30, 2021 and 2020, respectively. Net foreign currency transaction and remeasurement losses were $1.2 million and $2.8 million during the nine months ended June 30, 2021 and 2020, respectively.
Derivative Financial Instruments	Derivative Financial Instruments The Company has transactions and balances denominated in currencies other than U.S. dollars. Most of these transactions or balances are denominated in Euros, British Pounds and a variety of Asian currencies. The Company enters into foreign exchange contracts to reduce its exposure to currency fluctuations. The arrangements typically mature in three months or less and they do not qualify for hedge accounting. Net gains and losses related to these contracts are recorded as a component of "Other income (expenses), net" in the accompanying unaudited Consolidated Statements of Operations and are as follows for the three and nine months ended June 30, 2021 and 2020 (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ Nine Months Ended ​ ​ ​ June 30, ​ June 30, ​ ​ 2021 2020 2021 2020 Realized losses on derivatives not designated as hedging instruments ​ $ (961) ​ $ (1,719) ​ $ (7,295) ​ $ (963) ​ ​ The fair values of the forward contracts are recorded in the accompanying unaudited Consolidated Balance Sheets as “Prepaid expenses and other current assets” and “Accrued expenses and other current liabilities”. Foreign exchange contract assets and liabilities are measured and reported at fair value based on observable market inputs and classified within Level 2 of the fair value hierarchy described below due to a lack of an active market for these contracts.
Fair Value Measurements	Fair Value Measurements The Company measures certain financial assets and liabilities, including cash equivalents and available for sale securities, at fair value. FASB ASC 820, Fair Value Measurement and Disclosures Level 1 Inputs: Level 2 Inputs: Level 3 Inputs: As of June 30, 2021, the Company had no assets or liabilities measured and recorded at fair value on a recurring basis using Level 3 inputs.
Accounts Receivable, Allowance for Expected Credit Losses and Sales Returns	Accounts Receivable, Allowance for Expected Credit Losses and Sales Returns Trade accounts receivable do not bear interest and are recorded at the invoiced amount. The Company maintains an allowance for expected credit losses representing its best estimate of expected credit losses related to its existing accounts receivable and their net realizable value. The Company determines the allowance based on a number of factors, including an evaluation of customer credit worthiness, the age of the outstanding receivables, economic trends, historical experience and other information over the payment periods. The Company reviews and adjusts the allowance for expected credit losses on a quarterly basis. Accounts receivable balances are written off against the allowance for expected credit losses when the Company determines that the balances are not recoverable. Provisions for expected credit losses are recorded in “Selling, general and administrative” expenses in the Consolidated Statements of Operations. The Company determines the allowance for sales returns based on its best estimate of expected customer returns. Provisions for sales returns are recorded in "Revenue" in the Consolidated Statements of Operations. The Company does not have any off-balance-sheet credit exposure related to its customers.
Leases	Leases The Company has operating leases for real estate and non-real estate and finance leases for non-real estate. The classification of a lease as operating or finance and the determination of the right-of-use asset (“ROU asset”) and lease liability are determined at lease inception. The ROU asset represents the Company’s right to use an underlying asset for the lease term and the lease liability represents the Company’s obligation to make lease payments arising from the lease. Operating lease ROU assets and liabilities are recognized at the commencement date of the lease based on the present value of lease payments over the lease term. As most of the Company’s leases do not provide an implicit rate, an incremental borrowing rate is used based on the estimated rate of interest for collateralized borrowing over a similar term of the lease payments at commencement date. Lease terms may include options to extend or terminate the lease when it is reasonably certain that the option will be exercised. Lease expense is recognized on a straight-line basis over the lease term. The Company’s lease agreements may contain lease and non-lease components. Non-lease components primarily include payments for maintenance and utilities. Fixed payments for non-lease components are combined with lease payments and accounted for as a single lease component which increases the amount of the ROU asset and liability. The ROU asset for operating leases is included within “Other assets” and the ROU asset for finance leases is included within “Property, plant, and equipment, net” in the accompanying unaudited Consolidated Balance Sheets. The short-term lease liabilities for both operating leases and finance leases are included within “Accrued expenses and other current liabilities” in the accompanying unaudited Consolidated Balance Sheets. The long-term lease liabilities for operating leases and finance leases are included within “Long-term operating lease liabilities”, and “Other long-term liabilities”, respectively, in the accompanying unaudited Consolidated Balance Sheets.
Recently Issued Accounting Pronouncements	Recently Issued Accounting Pronouncements In October 2020 , the FASB issued Accounting Standards Update (“ASU”) 2020-10, Codification Improvements . The amendments in this ASU represent changes to clarify the ASCs, correct unintended application of guidance, or make minor improvements to the ASC that are not expected to have a significant effect on current accounting practice or create a significant administrative cost to most entities. ASU 2020-10 is effective for annual periods beginning after December 15, 2020 and interim periods within those annual periods, with early adoption permitted. The amendments in this ASU should be applied retrospectively. This ASU will not affect the Company's consolidated financial statements. The Company will adopt the provisions of this ASU in the first quarter of fiscal 2022 and is currently evaluating the impact this guidance may have on the disclosure to the consolidated financial statements. ​ In March 2020 , the FASB issued ASU 2020-04, Facilitation of the Effects of Reference Rate Reform on Financial Reporting . In January 2021, the FASB issued ASU 2021-01 , Reference Rate Reform (Topic 848): Scope . The amendments provide temporary optional expedients and exceptions to the GAAP guidance on contract modifications and hedge accounting to ease the financial reporting burdens related to the expected market transition from the London Interbank Offered Rate (LIBOR) and other interbank offered rates to alternative reference rates. The provisions of the amendments are only available until December 31, 2022, when the reference rate replacement activity is expected to be completed. The Company is currently evaluating the impact this guidance may have on its consolidated financial statements and related disclosures. ​ In December 2019 , the FASB issued ASU 2019-12, Simplifying the Accounting for Income Taxes (Topic 740) , which removes certain exceptions to the general principles in Topic 740 and improves consistent application of and simplifies GAAP for other areas of Topic 740 clarifying and amending existing guidance. This ASU is effective for annual periods, including interim periods within those annual periods, beginning after December 15, 2020. Early adoption is permitted. The Company will adopt the provisions of this ASU in the first quarter of fiscal 2022. The Company is currently evaluating the impact this guidance may have on its consolidated financial statements and related disclosures. ​ In August 2018 , the FASB issued ASU 2018-14, Disclosure Framework — Changes to the Disclosure Requirements for Defined Benefit Plans , which amends ASC 715 to add, remove, and clarify disclosure requirements related to defined benefit pension and other postretirement plans. The amendments require additional disclosure for the weighted-average interest crediting rates, a narrative description of the reasons for significant gains and losses, and an explanation of any other significant changes in the benefit obligation or plan assets. The amendment removes disclosure requirements for accumulated other comprehensive income expected to be recognized over the next year, information about plan assets to be returned to the entity, and the effects of a one-percentage-point change on the assumed health care costs and the effect of this change in rates on service cost, interest cost, and the benefit obligation for postretirement health care benefits. The ASU is effective for fiscal years ending after December 15, 2020. Early adoption is permitted. The ASU does not amend the interim disclosure requirements of ASC 715-20. The Company will adopt the provisions of this ASU in the first quarter of fiscal 2022 and is currently evaluating the impact this guidance may have on the disclosures in the consolidated financial statements. Recently Adopted Accounting Pronouncements In August 2018, the FASB issued ASU 2018-13, Fair Value Measurement (Topic 820): Disclosure Framework - Changes to the Disclosure Requirements for Fair Value Measurement , which amends ASC 820 to add and remove disclosure requirements related to fair value measurement. The amendments include new disclosure requirements for changes in unrealized gains or losses included in other comprehensive income for recurring Level 3 fair value measurements held at the end of the reporting period and the range and weighted average used to develop significant unobservable inputs for Level 3 fair value measurements. The amendments eliminated disclosure requirements for amount of and reasons for transfers between Level 1 and Level 2, valuation processes for Level 3 fair value measurements, and policy for timing of transfers between levels of the fair value hierarchy. In addition, the amendments modified certain disclosure requirements to provide clarification or to promote appropriate exercise of discretion by entities. ASU 2018-13 is effective for fiscal years beginning after December 15, 2019, including interim periods therein. The Company adopted the guidance during the first quarter of fiscal year 2021 . There is no significant accounting impact on the Company’s consolidated financial statements and related disclosures as a result of the adoption of this ASU. In August 2018, the FASB issued ASU 2018-15, Intangibles – Goodwill and Other – Internal-Use Software (Subtopic 350-40): Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract . The amendments align the requirements for capitalizing implementation costs incurred in a hosting arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software (and hosting arrangements that include an internal-use software license). The accounting for the service element of a hosting arrangement that is a service contract is not affected by these amendments. The provisions may be adopted prospectively or retrospectively. This ASU is effective for annual periods, including interim periods within those annual periods, beginning after December 15, 2019. The Company adopted the guidance during the first quarter of fiscal year 2021 on a prospective basis . There is no significant accounting impact on the Company’s consolidated financial statements and related disclosures as a result of the adoption of this ASU. In June 2016, the FASB issued ASU 2016-13, Financial Instruments - Credit Losses: Measurement of Credit Losses on Financial Instruments . The FASB subsequently issued ASU 2019-04, Codification Improvements to Topic 326, Financial Instruments - Credit Losses, Topic 815, Derivatives and Hedging, and Topic 825, Financial Instruments , ASU 2019-05 “Financial Instruments-Credit Losses” , ASU 2019-11, Codification Improvements to Topic 326, Financial Instruments - Credit Losses, and ASU 2020-02 , Financial Instruments-Credit Losses (Topic 326) and Leases (Topic 842) to clarify and address certain items related to the amendments in ASU 2016-13. Topic 326 provides guidance for recognizing credit losses on financial instruments based on an estimate of current expected credit losses model. The amendments are effective for fiscal years, and interim periods within those years, beginning after December 15, 2019. The Company adopted the guidance during the first quarter of fiscal year 2021 . There is no significant accounting impact on the Company’s consolidated financial statements and related disclosures as a result of the adoption of this ASU.
Other	Other For further information with regard to the Company’s significant accounting policies, please refer to Note 2 “Summary of Significant Accounting Policies” to the Company’s consolidated financial statements included in the 2020 Annual Report on Form 10-K.

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	9 Months Ended
	Jun. 30, 2021
Accounting Policies [Abstract]
Realized gains (losses) on derivatives not designated as hedging instruments	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ Nine Months Ended ​ ​ ​ June 30, ​ June 30, ​ ​ 2021 2020 2021 2020 Realized losses on derivatives not designated as hedging instruments ​ $ (961) ​ $ (1,719) ​ $ (7,295) ​ $ (963) ​

Discontinued Operations (Tables

Discontinued Operations (Tables)	9 Months Ended
	Jun. 30, 2021
Discontinued Operations and Disposal Groups [Abstract]
Schedule of discontinued operations	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended June 30, ​ ​ Nine Months Ended June 30, ​ ​ ​ ​ 2021 2020 ​ ​ 2021 2020 ​ Loss on discontinued operations before income taxes ​ ​ ​ $ (4) ​ $ - ​ ​ $ (1,534) ​ $ (239) ​ Net loss from discontinued operations ​ ​ ​ ​ (4) ​ ​ - ​ ​ ​ (1,168) ​ ​ (182) ​

Marketable Securities (Tables)

Marketable Securities (Tables)	9 Months Ended
	Jun. 30, 2021
Investments, Debt and Equity Securities [Abstract]
Summary of Amortized Cost and Fair Value, Including Accrued Interest Receivable and Unrealized Holding Gains (Losses) on Short-term and Long-term Marketable Securities	The following is a summary of the amortized cost and the fair value, including accrued interest receivable and unrealized holding gains (losses) on the short-term and long-term marketable securities as of June 30, 2021 and September 30, 2020 (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Gross Gross ​ ​ ​ Amortized ​ Unrealized ​ Unrealized ​ ​ ​ ​ Cost ​ Losses ​ Gains ​ Fair Value June 30, 2021: ​ ​ ​ ​ U.S. Treasury securities and obligations of U.S. government agencies $ 20 ​ $ — ​ $ — $ 20 Bank certificates of deposits ​ ​ 30 ​ ​ — ​ ​ — ​ ​ 30 Corporate securities ​ ​ 3,663 ​ ​ — ​ ​ — ​ ​ 3,663 Municipal securities ​ 25 ​ ​ — ​ ​ — ​ 25 ​ ​ $ 3,738 ​ $ — ​ $ — ​ $ 3,738 September 30, 2020: ​ ​ ​ ​ ​ Bank certificates of deposits ​ $ 51 ​ $ — ​ $ — ​ $ 51 Corporate securities ​ ​ 3,101 ​ ​ — ​ ​ — ​ ​ 3,101 Other debt securities ​ 16 ​ ​ — ​ ​ — ​ 16 ​ ​ $ 3,168 ​ $ — ​ $ — ​ $ 3,168
Fair Value of Marketable Securities by Contractual Maturity	The fair values of the marketable securities by contractual maturities at June 30, 2021 are presented below (in thousands): ​ ​ ​ ​ ​ Fair Value Due in one year or less ​ $ 101 Due after one year through five years ​ — Due after five years through ten years ​ ​ — Due after ten years ​ 3,637 Total marketable securities ​ $ 3,738

Goodwill and Intangible Assets

Goodwill and Intangible Assets (Tables)	9 Months Ended
	Jun. 30, 2021
Goodwill and Intangible Assets Disclosure [Abstract]
Components of Goodwill by Business Segment	The changes in the Company’s goodwill by reportable segment since September 30, 2020 are as follows (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Brooks ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Semiconductor ​ Brooks ​ Brooks ​ ​ ​ ​ ​ ​ ​ Solutions ​ Life Sciences ​ Life Sciences ​ ​ ​ ​ ​ ​ ​ Group ​ Products ​ Services ​ Other ​ Total Gross goodwill, at September 30, 2020 ​ $ 637,303 ​ $ 103,278 ​ $ 349,899 ​ $ 26,014 ​ $ 1,116,494 Accumulated goodwill impairments ​ (588,944) ​ — ​ ​ ​ (26,014) ​ (614,958) Goodwill, net of accumulated impairments, at September 30, 2020 ​ 48,359 ​ 103,278 ​ 349,899 ​ — ​ 501,536 Acquisitions and adjustments ​ 32,911 ​ 7,493 ​ 9,386 ​ — ​ 49,790 Gross goodwill, at June 30, 2021 ​ ​ 670,214 ​ ​ 110,771 ​ ​ 359,285 ​ ​ 26,014 ​ ​ 1,166,284 Accumulated goodwill impairments ​ (588,944) ​ — ​ ​ ​ (26,014) ​ (614,958) Goodwill, net of accumulated impairments, at June 30, 2021 ​ $ 81,270 ​ $ 110,771 ​ $ 359,285 ​ $ — ​ $ 551,326 ​
Components of Identifiable Intangible Assets	The components of the Company’s identifiable intangible assets as of June 30, 2021 and September 30, 2020 are as follows (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ June 30, 2021 ​ September 30, 2020 ​ ​ ​ ​ Accumulated ​ Net Book ​ ​ ​ Accumulated ​ Net Book ​ Cost Amortization Value Cost Amortization Value Patents ​ $ 5,302 ​ $ 5,013 ​ $ 289 ​ $ 5,302 ​ $ 4,865 ​ $ 437 Completed technology ​ 144,440 ​ 58,118 ​ 86,323 ​ 92,477 ​ 49,875 ​ 42,602 Trademarks and trade names ​ 27,625 ​ 12,102 ​ 15,523 ​ 25,769 ​ 9,322 ​ 16,447 Non-competition agreements ​ ​ 731 ​ ​ 129 ​ ​ 601 ​ ​ — ​ ​ — ​ ​ — Customer relationships ​ 285,685 ​ 133,488 ​ 152,197 ​ 271,113 ​ 112,277 ​ 158,836 Other intangibles ​ ​ 251 ​ ​ 248 ​ ​ 3 ​ ​ 245 ​ ​ 242 ​ ​ 3 ​ ​ $ 464,034 ​ $ 209,098 ​ $ 254,937 ​ $ 394,906 ​ $ 176,581 ​ $ 218,325
Schedule of Future Amortization Expense	Estimated future amortization expense for the intangible assets for the remainder of fiscal year 2021, the subsequent four fiscal years and thereafter is as follows (in thousands): ​ ​ ​ ​ Fiscal year ended September 30, ​ 2021 ​ $ 10,853 2022 ​ 40,414 2023 ​ 37,125 2024 ​ 32,242 2025 ​ 26,937 Thereafter ​ 107,366 ​ ​ $ 254,937

Debt (Tables)

Debt (Tables)	9 Months Ended
	Jun. 30, 2021
Debt Disclosure [Abstract]
Schedule of Future Minimum Principal Payment Obligations	The following are the future minimum principal payment obligations under all of the Company’s outstanding debt as of June 30, 2021 (in thousands): ​ ​ ​ ​ ​ ​ Amount Fiscal year ended September 30, ​ ​ ​ 2021 ​ $ — 2022 ​ ​ — 2023 ​ ​ — 2024 ​ ​ — 2025 ​ ​ 50,000 Total outstanding principal balance ​ ​ 50,000 Unamortized deferred financing costs ​ ​ (349) ​ ​ ​ 49,651 Current portion of long-term debt ​ ​ — Non-current portion of long-term debt ​ $ 49,651

Leases (Tables)

Leases (Tables)	9 Months Ended
	Jun. 30, 2021
Leases [Abstract]
Schedule of leases	The components of lease expense were as follows (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended June 30, ​ Nine Months Ended June 30, ​ ​ ​ ​ ​ ​ 2021 ​ 2020 ​ 2021 ​ 2020 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating lease costs ​ ​ ​ $ 2,878 ​ $ 2,358 ​ $ 8,135 ​ $ 6,755 ​ ​ ​ Finance lease costs: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Amortization of assets ​ ​ ​ ​ 182 ​ ​ 311 ​ ​ 745 ​ ​ 933 ​ ​ ​ Interest on lease liabilities ​ ​ ​ ​ 10 ​ ​ 29 ​ ​ 31 ​ ​ 84 ​ ​ ​ Total finance lease costs ​ ​ ​ ​ 192 ​ ​ 340 ​ ​ 776 ​ ​ 1,017 ​ ​ ​ Variable lease costs ​ ​ ​ ​ 514 ​ ​ 448 ​ ​ 1,578 ​ ​ 1,314 ​ ​ ​ Short-term lease costs ​ ​ ​ ​ 123 ​ ​ 181 ​ ​ 349 ​ ​ 477 ​ ​ ​ Total lease costs ​ ​ ​ $ 3,707 ​ $ 3,327 ​ $ 10,838 ​ $ 9,563 ​ ​ ​ ​ Supplemental balance sheet information related to leases is as follows (in thousands, except lease term and discount rate): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ June 30, 2021 ​ September 30, 2020 ​ Operating Leases: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating lease right-of-use assets ​ ​ ​ ​ ​ ​ ​ ​ ​ $ 52,159 ​ $ 39,071 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Accrued expenses and other current liabilities ​ ​ ​ ​ ​ ​ ​ ​ ​ $ 7,489 ​ $ 7,015 ​ Long-term operating lease liabilities ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 45,034 ​ ​ 31,855 ​ Total operating lease liabilities ​ ​ ​ ​ ​ ​ ​ ​ ​ $ 52,523 ​ $ 38,870 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Finance Leases: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Property, plant and equipment, at cost ​ ​ ​ ​ ​ ​ ​ ​ ​ $ 2,252 ​ $ 2,540 ​ Accumulated amortization ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (1,989) ​ ​ (1,246) ​ Property, plant and equipment, net ​ ​ ​ ​ ​ ​ ​ ​ ​ $ 263 ​ $ 1,294 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Accrued expenses and other current liabilities ​ ​ ​ ​ ​ ​ ​ ​ ​ $ 610 ​ $ 1,135 ​ Other long-term liabilities ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (10) ​ ​ 348 ​ Total finance lease liabilities ​ ​ ​ ​ ​ ​ ​ ​ ​ $ 600 ​ $ 1,483 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted average remaining lease term (in years): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating leases ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 10.73 ​ ​ 8.72 ​ Finance leases ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 0.71 ​ ​ 1.32 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted average discount rate: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating leases ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 4.02 % ​ 3.92 % Finance leases ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 4.81 % ​ 4.73 % ​ Supplemental cash flow information related to leases was as follows (in thousands, unaudited): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended June 30, ​ Nine Months Ended June 30, ​ ​ ​ ​ ​ ​ 2021 ​ 2020 ​ 2021 ​ 2020 ​ ​ ​ Cash paid for amounts included in measurement of liabilities: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating cash flows from operating leases ​ ​ ​ $ 2,532 ​ $ 2,215 ​ $ 7,530 ​ $ 6,089 ​ ​ ​ Operating cash flows from finance leases ​ ​ ​ ​ 8 ​ ​ 22 ​ ​ 35 ​ ​ 77 ​ ​ ​ Financing cash flows from finance leases ​ ​ ​ ​ 269 ​ ​ 297 ​ ​ 881 ​ ​ 880 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ROU assets obtained in exchange for lease liabilities: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating leases ​ ​ ​ $ 14,066 ​ $ 3,026 ​ $ 19,033 ​ $ 13,753 ​ ​ ​
Schedule of future lease payments of operating leases - ASC 842	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating Leases ​ Finance Leases ​ ​ Fiscal year ended September 30, ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 2021 ​ ​ ​ ​ ​ ​ ​ ​ ​ $ 2,501 ​ $ 251 ​ ​ ​ 2022 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 9,032 ​ ​ 363 ​ ​ ​ 2023 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 7,286 ​ ​ - ​ ​ ​ 2024 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 6,378 ​ ​ - ​ ​ ​ 2025 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 5,779 ​ ​ - ​ ​ ​ Thereafter ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 34,475 ​ ​ - ​ ​ ​ Total future lease payments ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 65,451 ​ ​ 614 ​ ​ ​ Less imputed interest ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (12,928) ​ ​ (14) ​ ​ ​ Total lease liability balance ​ ​ ​ ​ ​ ​ ​ ​ ​ $ 52,523 ​ $ 600 ​ ​ ​ ​
Schedule of future lease payments of finance leases - ASC 842	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating Leases ​ Finance Leases ​ ​ Fiscal year ended September 30, ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 2021 ​ ​ ​ ​ ​ ​ ​ ​ ​ $ 2,501 ​ $ 251 ​ ​ ​ 2022 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 9,032 ​ ​ 363 ​ ​ ​ 2023 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 7,286 ​ ​ - ​ ​ ​ 2024 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 6,378 ​ ​ - ​ ​ ​ 2025 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 5,779 ​ ​ - ​ ​ ​ Thereafter ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 34,475 ​ ​ - ​ ​ ​ Total future lease payments ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 65,451 ​ ​ 614 ​ ​ ​ Less imputed interest ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (12,928) ​ ​ (14) ​ ​ ​ Total lease liability balance ​ ​ ​ ​ ​ ​ ​ ​ ​ $ 52,523 ​ $ 600 ​ ​ ​ ​ ​

Other Balance Sheet Informati_2

Other Balance Sheet Information (Tables)	9 Months Ended
	Jun. 30, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Summary of Accounts Receivable	The following is a summary of accounts receivable at June 30, 2021 and September 30, 2020 (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ June 30, ​ September 30, ​ ​ 2021 2020 Accounts receivable ​ $ 238,890 ​ $ 195,587 ​ Less allowance for expected credit losses ​ (4,737) ​ (7,216) ​ Less allowance for sales returns ​ (74) ​ (80) ​ Accounts receivable, net ​ $ 234,079 ​ $ 188,291 ​
Summary of Inventories	The decrease in the allowance for expected credit losses from September 30, 2020 is due to collections of previously reserved trade receivables in the Brooks Life Sciences Services segment during the first quarter of fiscal year 2021. The following is a summary of inventories at June 30, 2021 and September 30, 2020 (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ June 30, ​ September 30, ​ ​ 2021 2020 Inventories ​ ​ ​ Raw materials and purchased parts ​ $ 98,997 ​ $ 73,609 ​ Work-in-process ​ 21,356 ​ 16,461 ​ Finished goods ​ 34,367 ​ 24,764 ​ Total inventories ​ $ 154,720 ​ $ 114,834 ​
Product Warranty and Retrofit Activity on Gross Basis	The following is a summary of product warranty and retrofit activity on a gross basis for the three and nine months ended June 30, 2021 and 2020 (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Activity -Three Months Ended June 30, 2021 Balance ​ ​ ​ ​ Balance March 31, ​ ​ ​ ​ ​ ​ ​ June 30, 2021 ​ Accruals ​ Costs Incurred ​ 2021 $ 8,044 ​ $ 1,892 ​ $ (1,804) ​ $ 8,132 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Activity -Three Months Ended June 30, 2020 Balance ​ ​ ​ ​ Balance March 31, ​ ​ ​ ​ ​ ​ ​ June 30, 2020 ​ Accruals ​ Costs Incurred ​ 2020 $ 7,910 ​ $ 1,380 ​ $ (1,409) ​ $ 7,881 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Activity -Nine Months Ended June 30, 2021 Balance ​ ​ ​ ​ Balance September 30, ​ ​ ​ ​ ​ ​ ​ June 30, 2020 ​ Accruals ​ Costs Incurred ​ 2021 $ 8,201 ​ $ 5,990 ​ $ (6,059) ​ $ 8,132 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Activity -Nine Months Ended June 30, 2020 Balance ​ ​ ​ ​ Balance September 30, ​ ​ ​ ​ ​ ​ ​ June 30, 2019 ​ Accruals ​ Costs Incurred ​ 2020 $ 7,175 ​ $ 6,033 ​ $ (5,327) ​ $ 7,881

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	9 Months Ended
	Jun. 30, 2021
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Summary of stock-based compensation expense	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended June 30, ​ Nine Months Ended June 30, ​ ​ 2021 2020 2021 2020 Restricted stock units ​ $ 5,475 ​ $ 3,348 ​ $ 18,667 ​ $ 11,361 ​ Employee stock purchase plan ​ 611 ​ 377 ​ 1,610 ​ 987 ​ Total stock-based compensation expense ​ $ 6,086 ​ $ 3,725 ​ $ 20,277 ​ $ 12,348 ​ ​
Restricted Stock Unit Activity	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Time-Based Stock Performance- ​ ​ Total Units ​ Units ​ Grants ​ Based Units Nine months ended June 30, 2021 346,172 162,842 14,683 168,647 Nine months ended June 30, 2020 411,967 163,390 27,007 221,570 ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ ​ ​ ​ Average ​ ​ ​ ​ Grant-Date ​ ​ Shares ​ Fair Value Outstanding at September 30, 2020 1,183,009 ​ $ 36.10 Granted 346,172 ​ ​ 71.81 Vested (406,764) ​ ​ 36.01 Forfeited (32,600) ​ ​ 44.27 Outstanding at June 30, 2021 1,089,817 ​ ​ 47.23

Earnings per Share (Tables)

Earnings per Share (Tables)	9 Months Ended
	Jun. 30, 2021
Earnings Per Share [Abstract]
Reconciliation of Weighted Average Common Shares Outstanding for Purposes of Calculating Basic and Diluted Earnings Per Share	The calculations of basic and diluted net income per share and basic and diluted weighted average shares outstanding are as follows for the three and nine months ended June 30, 2021 and 2020 (in thousands, except per share data): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ Nine Months Ended ​ ​ ​ June 30, ​ June 30, ​ ​ 2021 2020 2021 2020 Income from continuing operations ​ $ 39,170 ​ $ 13,696 ​ $ 90,110 ​ $ 36,062 ​ Loss from discontinued operations, net of tax ​ (4) ​ — ​ (1,168) ​ (182) ​ Net income ​ $ 39,166 ​ $ 13,696 ​ $ 88,942 ​ $ 35,880 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted average common shares outstanding used in computing basic earnings per share ​ 74,296 ​ 73,759 ​ 74,195 ​ 73,473 ​ Dilutive restricted stock units ​ 199 ​ 101 ​ 225 ​ 293 ​ Weighted average common shares outstanding used in computing diluted earnings per share ​ 74,495 ​ 73,860 ​ 74,420 ​ 73,766 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Basic net income per share: ​ ​ ​ ​ ​ Income from continuing operations ​ $ 0.53 ​ $ 0.19 ​ $ 1.21 ​ $ 0.49 ​ Loss from discontinued operations, net of tax ​ (0.00) ​ - ​ (0.02) ​ (0.00) ​ Basic net income per share ​ $ 0.53 ​ $ 0.19 ​ $ 1.20 ​ $ 0.49 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Diluted net income per share: ​ ​ ​ ​ ​ Income from continuing operations ​ $ 0.53 ​ $ 0.19 ​ $ 1.21 ​ $ 0.49 ​ Loss from discontinued operations, net of tax ​ (0.00) ​ — ​ (0.02) ​ (0.00) ​ Diluted net income per share ​ $ 0.53 ​ $ 0.19 ​ $ 1.20 ​ $ 0.49 ​ Dividend declared per share ​ $ 0.10 ​ $ 0.10 ​ $ 0.30 ​ $ 0.30 ​

Revenue from Contracts with C_2

Revenue from Contracts with Customers (Tables)	9 Months Ended
	Jun. 30, 2021
Revenue from Contract with Customer [Abstract]
Revenue by Reporting Unit	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three months ended June 30, ​ Nine months ended June 30, ​ ​ ​ 2021 ​ 2020 ​ 2021 ​ 2020 Reporting Unit ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Automation Solutions ​ ​ $ 122,567 ​ $ 81,656 ​ $ 320,540 ​ $ 214,627 Contamination Control Solutions ​ ​ ​ 50,742 ​ ​ 34,780 ​ ​ 117,236 ​ ​ 124,584 Global Semiconductor Services ​ ​ ​ 12,953 ​ ​ 10,616 ​ ​ 36,898 ​ ​ 31,575 Total Brooks Semiconductor Solutions Group ​ ​ ​ 186,262 ​ ​ 127,052 ​ ​ 474,674 ​ ​ 370,786 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Brooks Life Sciences Products ​ ​ ​ 48,625 ​ ​ 30,421 ​ ​ 146,490 ​ ​ 91,138 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Brooks Life Sciences Services ​ ​ ​ 80,462 ​ ​ 62,877 ​ ​ 230,275 ​ ​ 189,153 Total ​ ​ $ 315,349 ​ $ 220,350 ​ $ 851,439 ​ $ 651,077 ​
Remaining Performance Obligations	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of June 30, 2021 ​ ​ ​ ​ ​ Less than 1 Year ​ Greater than 1 Year ​ Total Remaining Performance Obligations ​ ​ ​ ​ $ 46,552 ​ $ 18,677 ​ $ 65,229 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

Segment Information (Tables)

Segment Information (Tables)	9 Months Ended
	Jun. 30, 2021
Segment Reporting [Abstract]
Financial Information for Business Segments	The following is the summary of the financial information for the Company’s reportable segments for the three and nine months ended June 30, 2021 and 2020 (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended June 30, ​ ​ Nine Months Ended June 30, ​ ​ ​ 2021 ​ 2020 ​ 2021 ​ 2020 ​ Revenue: ​ ​ ​ ​ ​ ​ ​ ​ Brooks Semiconductor Solutions Group ​ $ 186,262 ​ $ 127,052 ​ $ 474,674 ​ $ 370,786 ​ Brooks Life Sciences Products ​ ​ 48,625 ​ ​ 30,421 ​ ​ 146,490 ​ ​ 91,138 ​ Brooks Life Sciences Services ​ 80,462 ​ 62,877 ​ 230,275 ​ 189,153 ​ Total revenue ​ $ 315,349 ​ $ 220,350 ​ $ 851,439 ​ $ 651,077 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating income: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Brooks Semiconductor Solutions Group ​ $ 44,797 ​ $ 23,414 ​ $ 99,637 ​ $ 55,120 ​ Brooks Life Sciences Products ​ ​ 9,138 ​ ​ 2,482 ​ ​ 28,295 ​ ​ 4,988 ​ Brooks Life Sciences Services ​ 13,783 ​ 4,109 ​ 41,501 ​ 15,695 ​ Reportable segment adjusted operating income ​ ​ 67,718 ​ ​ 30,005 ​ ​ 169,433 ​ ​ 75,803 ​ Amortization of completed technology ​ ​ 3,352 ​ ​ 2,779 ​ ​ 8,060 ​ ​ 8,194 ​ Amortization of other intangible assets ​ ​ 7,733 ​ ​ 7,611 ​ ​ 22,690 ​ ​ 23,137 ​ Restructuring charges ​ ​ — ​ ​ (29) ​ ​ 179 ​ ​ 1,125 ​ Tariff adjustment ​ ​ — ​ ​ — ​ ​ 5,414 ​ ​ — ​ Other unallocated corporate expenses (income) ​ ​ 6,400 ​ ​ 545 ​ ​ 21,423 ​ ​ (990) ​ Total operating income ​ ​ 50,233 ​ ​ 19,099 ​ ​ 111,667 ​ ​ 44,337 ​ Interest income ​ ​ 409 ​ ​ 29 ​ ​ 503 ​ ​ 865 ​ Interest expense ​ ​ (477) ​ ​ (810) ​ ​ (1,485) ​ ​ (2,265) ​ Other income (expenses), net ​ ​ (1,625) ​ ​ 498 ​ ​ (147) ​ ​ (1,318) ​ Income before income taxes ​ $ 48,540 ​ $ 18,816 ​ $ 110,538 ​ $ 41,619 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Brooks ​ ​ ​ ​ ​ ​ ​ ​ Semiconductor ​ Brooks Life ​ Brooks Life ​ ​ ​ Assets: ​ ​ Solutions Group ​ Sciences Products ​ Sciences Services ​ Total ​ June 30, 2021 ​ $ 433,108 ​ $ 259,592 ​ $ 779,798 ​ $ 1,472,498 ​ September 30, 2020 ​ ​ 296,289 ​ 214,196 ​ ​ 737,967 ​ 1,248,452 ​ ​ ​
Reconciliation of Reportable Segment Assets to Corresponding Consolidated Amounts	​ ​ ​ ​ ​ ​ ​ ​ June 30, September 30, ​ ​ 2021 ​ 2020 Segment assets $ 1,472,498 $ 1,248,452 Cash and cash equivalents, restricted cash, and marketable securities ​ 286,310 ​ 305,694 Deferred tax assets ​ 4,447 ​ 4,979 Total assets ​ $ 1,763,255 ​ $ 1,559,125
Revenue from External Customers Attributed to Geographic Areas	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended June 30, ​ ​ Nine Months Ended June 30, ​ 2021 ​ 2020 ​ 2021 ​ 2020 Geographic Location: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Asia / Pacific/ Other ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ China ​ $ 55,062 ​ $ 30,228 ​ $ 137,945 ​ $ 76,435 Taiwan ​ ​ 29,844 ​ ​ 15,266 ​ ​ 73,350 ​ ​ 91,993 Republic of Korea ​ ​ 28,994 ​ ​ 22,369 ​ ​ 77,982 ​ ​ 46,296 Other ​ ​ 37,186 ​ ​ 31,552 ​ ​ 105,861 ​ ​ 93,245 ​ ​ ​ 151,086 ​ ​ 99,415 ​ ​ 395,138 ​ ​ 307,969 North America ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ USA ​ ​ 108,344 ​ ​ 79,032 ​ ​ 290,883 ​ ​ 243,883 Other ​ ​ 2,110 ​ ​ 850 ​ ​ 22,947 ​ ​ 2,117 ​ ​ ​ 110,454 ​ ​ 79,882 ​ ​ 313,830 ​ ​ 246,000 Europe ​ ​ 53,809 ​ ​ 41,053 ​ ​ 142,471 ​ ​ 97,108 Total ​ $ 315,349 ​ $ 220,350 ​ $ 851,439 ​ $ 651,077 ​

Summary of Significant Accoun_4

Summary of Significant Accounting Policies - Foreign Currency Translation (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Foreign Currency Transaction Gain (Loss), before Tax [Abstract]
Foreign currency transaction and remeasurement losses	$ (1.6)		$ (1.2)	$ (2.8)
Maximum
Foreign Currency Transaction Gain (Loss), before Tax [Abstract]
Foreign currency transaction and remeasurement losses		$ (0.1)

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - Derivative Instruments (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net [Abstract]
Realized losses on derivatives not designated as hedging instruments	$ (961)	$ (1,719)	$ (7,295)	$ (963)

Summary of Significant Accoun_6

Summary of Significant Accounting Policies - Fair Value Measurements (Details) - Fair Value, Measurements, Recurring - Significant Unobservable Inputs (Level 3) $ in Millions	Jun. 30, 2021USD ($)
Assets
Assets measured at fair value	$ 0
Liabilities
Liabilities measured at fair value	$ 0

Summary of Significant Accoun_7

Summary of Significant Accounting Policies - Recently Issued and Adopted Accounting Pronouncements (Details)	9 Months Ended
	Jun. 30, 2021
Accounting Standards Update 2020-10
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Change in Accounting Principle, Accounting Standards Update, Adopted	false
Accounting Standards Update 2020-04
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Change in Accounting Principle, Accounting Standards Update, Adopted	false
Accounting Standards Update 2019-12
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Change in Accounting Principle, Accounting Standards Update, Adopted	false
Accounting Standards Update 2018-14
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Change in Accounting Principle, Accounting Standards Update, Adopted	false
Accounting Standards Update 2018-13
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Change in Accounting Principle, Accounting Standards Update, Adopted	true
Change in Accounting Principle, Accounting Standards Update, Adoption Date	Oct. 1, 2020
Accounting Standards Update 2018-15
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Change in Accounting Principle, Accounting Standards Update, Adopted	true
Change in Accounting Principle, Accounting Standards Update, Adoption Date	Oct. 1, 2020
Change in Accounting Principle, Accounting Standards Update, Transition Option Elected	us-gaap:AccountingStandardsUpdate201815ProspectiveMember
Accounting Standards Update 2016-13
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Change in Accounting Principle, Accounting Standards Update, Adopted	true
Change in Accounting Principle, Accounting Standards Update, Adoption Date	Oct. 1, 2020

Discontinued Operations - Gener

Discontinued Operations - General Information (Details) - USD ($) $ in Millions	Jul. 01, 2019	Aug. 27, 2018	Dec. 31, 2020
Edwards Vacuum LLC
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Transition service agreement, term, high end of range		9 months
Aggregate amount to purchase goods		$ 1
Supply agreement term		1 year
Lease term		3 years
Option to renew		true
Ulvac Cryogenics Incorporated
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Ownership interest (as a percent)		50.00%
Discontinued Operations, Held-for-sale | Semiconductor Cryogenics Business
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Consideration		$ 675
Discontinued operation, name of segment		Brooks Semiconductor Solutions Group
Discontinued Operations, Disposed of by Sale | Semiconductor Cryogenics Business
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Consideration	$ 659.8
Net working capital adjustments			$ (1.8)
Net cash proceeds from the sale	$ 551.7

Discontinued Operations - Finan

Discontinued Operations - Financial Results (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Jun. 30, 2021	Jun. 30, 2021	Jun. 30, 2020
Disposal Group, Including Discontinued Operation, Income Statement Disclosures [Abstract]
Net loss from discontinued operations	$ (4)	$ (1,168)	$ (182)
Discontinued Operations, Held-for-sale
Disposal Group, Including Discontinued Operation, Income Statement Disclosures [Abstract]
Loss on discontinued operations before income taxes	(4)	(1,534)	(239)
Net loss from discontinued operations	$ (4)	$ (1,168)	$ (182)

Marketable Securities - General

Marketable Securities - General Information (Details) - USD ($) $ in Thousands	9 Months Ended
	Jun. 30, 2021	Jun. 30, 2020
Schedule of Available-for-sale Securities [Line Items]
Marketable securities sold during period, fair value		$ 2,500
Marketable securities sold during period, amortized cost basis		2,500
Sales of marketable securities	$ 25	2,492
Maximum
Schedule of Available-for-sale Securities [Line Items]
Net realized gain, (loss)		100
Reclassification unrealized net holding gain, (loss)		$ 100

Marketable Securities - Summary

Marketable Securities - Summary of Amortized Cost and Fair Value (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Sep. 30, 2020
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 3,738	$ 3,168
Fair Value	3,738	3,168
U.S. Treasury securities and obligations of U.S. government agencies
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	20
Fair Value	20
Certificates of Deposit
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	30	51
Fair Value	30	51
Corporate securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	3,663	3,101
Fair Value	3,663	3,101
Municipal securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	25
Fair Value	$ 25
Other debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost		16
Fair Value		$ 16

Marketable Securities - Fair Va

Marketable Securities - Fair Value of Marketable Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Sep. 30, 2020
Investments, Debt and Equity Securities [Abstract]
Due in one year or less (remainder of year)	$ 101
Due in one year	0
Due after ten years	3,637
Fair Value	$ 3,738	$ 3,168

Marketable Securities - Unreali

Marketable Securities - Unrealized Loss Position (Details) - USD ($) $ in Millions	Jun. 30, 2021	Sep. 30, 2020
Debt Securities, Available-for-sale, Unrealized Loss Position [Abstract]
Fair value of marketable securities in unrealized loss position	$ 0	$ 0

Marketable Securities - Cash Eq

Marketable Securities - Cash Equivalents (Details) - Fair Value, Measurements, Recurring - USD ($) $ in Thousands	Jun. 30, 2021	Sep. 30, 2020
Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets:
Cash equivalents		$ 0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Money Market Funds | Maximum
Assets:
Cash equivalents	$ 100
Significant Other Observable Inputs (Level 2)
Assets:
Cash equivalents		$ 100

Acquisitions - General Informat

Acquisitions - General Information (Details)	Apr. 29, 2021
Precise Automation, Inc.
Business Acquisition, Date of Acquisition [Abstract]
Business Acquisition, Effective Date of Acquisition	Apr. 29, 2021

Acquisitions - Purchase Conside

Acquisitions - Purchase Consideration (Details) - USD ($) $ in Thousands	Apr. 29, 2021	Apr. 01, 2021	Dec. 03, 2020	Feb. 11, 2020	Jun. 30, 2021	Jun. 30, 2021	Jun. 30, 2020
Business Acquisition [Line Items]
Net cash outflow						$ 92,375	$ 15,743
Precise Automation, Inc.
Business Acquisition [Line Items]
Total purchase price	$ 69,600
Other Acquisition, Closed Third Quarter, Fiscal Year 2021
Business Acquisition [Line Items]
Additional potential contingent consideration					$ 9,400	$ 9,400
Other Acquisition, Closed Third Quarter, Fiscal Year 2021 | Maximum
Business Acquisition [Line Items]
Total purchase price					$ 19,300
Trans-Hit Biomarkers
Business Acquisition [Line Items]
Total purchase price			$ 15,100
RURO, Inc.
Business Acquisition [Line Items]
Total purchase price				$ 15,200
Working capital adjustment received		$ 500

Acquisitions - Amounts of Asset

Acquisitions - Amounts of Assets and Liabilities at Fair Value as of Acquisition Date (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Apr. 29, 2021	Dec. 03, 2020	Sep. 30, 2020	Feb. 11, 2020
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net [Abstract]
Goodwill	$ 551,326			$ 501,536
Precise Automation, Inc.
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net [Abstract]
Goodwill		$ 32,900
Deferred tax liabilities		6,200
Other Acquisition, Closed Third Quarter, Fiscal Year 2021
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net [Abstract]
Goodwill	4,400
Trans-Hit Biomarkers
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net [Abstract]
Goodwill			$ 9,300
Intangible assets			7,800
Deferred tax liabilities			$ 2,400
RURO, Inc.
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net [Abstract]
Accounts receivable					$ 600
Goodwill					11,000
Liabilities					2,700
Completed Technology | Precise Automation, Inc.
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net [Abstract]
Intangible assets		38,900
Completed Technology | Other Acquisition, Closed Third Quarter, Fiscal Year 2021
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net [Abstract]
Intangible assets	$ 11,900
Completed Technology | RURO, Inc.
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net [Abstract]
Intangible assets					2,900
Customer Relationships | Precise Automation, Inc.
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net [Abstract]
Intangible assets		$ 2,400
Customer Relationships | RURO, Inc.
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net [Abstract]
Intangible assets					$ 2,900

Acquisitions - Intangible Asset

Acquisitions - Intangible Assets Acquired (Details)	Apr. 29, 2021	Dec. 03, 2020	Jun. 30, 2021
Precise Automation, Inc.
Acquired Finite-Lived Intangible Assets [Line Items]
Weighted average useful life of intangible assets	11 years
Other Acquisition, Closed Third Quarter, Fiscal Year 2021
Acquired Finite-Lived Intangible Assets [Line Items]
Weighted average useful life of intangible assets			12 years
Trans-Hit Biomarkers
Acquired Finite-Lived Intangible Assets [Line Items]
Weighted average useful life of intangible assets		11 years

Acquisitions - Goodwill (Detail

Acquisitions - Goodwill (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Apr. 29, 2021	Dec. 03, 2020	Sep. 30, 2020	Feb. 11, 2020
Goodwill
Goodwill	$ 551,326			$ 501,536
Brooks Semiconductor Solutions Group
Goodwill
Goodwill	81,270			48,359
Brooks Life Sciences Products
Goodwill
Goodwill	110,771			103,278
Brooks Life Sciences Services
Goodwill
Goodwill	359,285			$ 349,899
Precise Automation, Inc.
Goodwill
Goodwill		$ 32,900
Goodwill deductible for tax purposes		$ 0
Other Acquisition, Closed Third Quarter, Fiscal Year 2021
Goodwill
Goodwill	4,400
Goodwill deductible for tax purposes	$ 4,400
Trans-Hit Biomarkers
Goodwill
Goodwill			$ 9,300
Goodwill deductible for tax purposes			$ 0
RURO, Inc.
Goodwill
Goodwill					$ 11,000
Goodwill deductible for tax purposes					$ 0

Goodwill and Intangible Asset_2

Goodwill and Intangible Assets - Goodwill Impairment Test (Details) $ in Thousands	3 Months Ended
	Jun. 30, 2021USD ($)
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill impairment	$ 0

Goodwill and Intangible Asset_3

Goodwill and Intangible Assets - Components of Goodwill by Operating Segment (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Sep. 30, 2020
Goodwill [Line Items]
Gross goodwill	$ 1,166,284	$ 1,116,494
Accumulated goodwill impairments	(614,958)	(614,958)
Goodwill	551,326	501,536
Brooks Semiconductor Solutions Group
Goodwill [Line Items]
Gross goodwill	670,214	637,303
Accumulated goodwill impairments	(588,944)	(588,944)
Goodwill	81,270	48,359
Brooks Life Sciences Products
Goodwill [Line Items]
Gross goodwill	110,771	103,278
Goodwill	110,771	103,278
Brooks Life Sciences Services
Goodwill [Line Items]
Gross goodwill	359,285	349,899
Goodwill	359,285	349,899
Other
Goodwill [Line Items]
Gross goodwill	26,014	26,014
Accumulated goodwill impairments	$ (26,014)	$ (26,014)

Goodwill and Intangible Asset_4

Goodwill and Intangible Assets - Goodwill Roll Forward (Details) $ in Thousands	9 Months Ended
	Jun. 30, 2021USD ($)
Goodwill [Roll Forward]
Goodwill, net of accumulated impairments, beginning balance	$ 501,536
Acquisitions and adjustments	49,790
Goodwill, net of accumulated impairments, ending balance	551,326
Brooks Semiconductor Solutions Group
Goodwill [Roll Forward]
Goodwill, net of accumulated impairments, beginning balance	48,359
Acquisitions and adjustments	32,911
Goodwill, net of accumulated impairments, ending balance	81,270
Brooks Life Sciences Products
Goodwill [Roll Forward]
Goodwill, net of accumulated impairments, beginning balance	103,278
Acquisitions and adjustments	7,493
Goodwill, net of accumulated impairments, ending balance	110,771
Brooks Life Sciences Services
Goodwill [Roll Forward]
Goodwill, net of accumulated impairments, beginning balance	349,899
Acquisitions and adjustments	9,386
Goodwill, net of accumulated impairments, ending balance	$ 359,285

Goodwill and Intangible Asset_5

Goodwill and Intangible Assets - Goodwill Acquired (Details) $ in Millions	9 Months Ended
	Jun. 30, 2021USD ($)
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill acquired during period	$ 49.8

Goodwill and Intangible Asset_6

Goodwill and Intangible Assets - Components of Identifiable Intangible Assets (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Sep. 30, 2020
Finite-Lived Intangible Assets [Line Items]
Cost	$ 464,034	$ 394,906
Accumulated Amortization	209,098	176,581
Net Book Value	254,937	218,325
Patents
Finite-Lived Intangible Assets [Line Items]
Cost	5,302	5,302
Accumulated Amortization	5,013	4,865
Net Book Value	289	437
Completed Technology
Finite-Lived Intangible Assets [Line Items]
Cost	144,440	92,477
Accumulated Amortization	58,118	49,875
Net Book Value	86,323	42,602
Trademarks and Trade Names
Finite-Lived Intangible Assets [Line Items]
Cost	27,625	25,769
Accumulated Amortization	12,102	9,322
Net Book Value	15,523	16,447
Noncompete Agreements
Finite-Lived Intangible Assets [Line Items]
Cost	731
Accumulated Amortization	129
Net Book Value	601
Customer Relationships
Finite-Lived Intangible Assets [Line Items]
Cost	285,685	271,113
Accumulated Amortization	133,488	112,277
Net Book Value	152,197	158,836
Other Intangible Assets
Finite-Lived Intangible Assets [Line Items]
Cost	251	245
Accumulated Amortization	248	242
Net Book Value	$ 3	$ 3

Goodwill and Intangible Asset_7

Goodwill and Intangible Assets - Amortization Expense (Details) - USD ($) $ in Millions	9 Months Ended
	Jun. 30, 2021	Jun. 30, 2020
Goodwill and Intangible Assets Disclosure [Abstract]
Amortization of intangible assets	$ 30.8	$ 31.3

Goodwill and Intangible Asset_8

Goodwill and Intangible Assets - Estimated Future Amortization Expense of Intangible Assets (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Sep. 30, 2020
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract]
2021	$ 10,853
2022	40,414
2023	37,125
2024	32,242
2025	26,937
Thereafter	107,366
Net Book Value	$ 254,937	$ 218,325

Line of Credit (Details)

Line of Credit (Details) - USD ($) $ in Millions	9 Months Ended
	Jun. 30, 2021	Sep. 30, 2020	Oct. 04, 2017
Line of Credit | Credit Agreement | Revolving Credit Facility
Line of Credit Facility [Line Items]
Line of credit, maximum borrowing capacity	$ 75		$ 75
Line of credit, expiration date	Oct. 4, 2022
Outstanding line of credit	$ 0	$ 0
Deferred finance costs	0.2	$ 0.4
Line of credit, remaining borrowing capacity	$ 49.8
Line of Credit | Credit Agreement | Revolving Credit Facility | Maximum
Line of Credit Facility [Line Items]
Line of credit, expiration period	90 days
Line of Credit | Credit Agreement | Letter of Credit
Line of Credit Facility [Line Items]
Line of credit, maximum borrowing capacity			7.5
Secured Debt | Senior Secured Term Loan Facility
Line of Credit Facility [Line Items]
Face amount			$ 200

Debt - General Information (Det

Debt - General Information (Details) $ in Millions	Jul. 01, 2019USD ($)loan	Feb. 15, 2019USD ($)	Nov. 15, 2018USD ($)	Oct. 04, 2017USD ($)
Debt Instrument [Line Items]
Issue amount		$ 345.2
Aggregate increase amount				$ 75
Maximum secured leverage ratio				3
Secured Debt
Debt Instrument [Line Items]
Loss on extinguishment of debt	$ 5.2
Number of term loans | loan	2
Senior Secured Term Loan Facility | Secured Debt
Debt Instrument [Line Items]
Debt extinguished	$ 147
Face amount				$ 200
Issue amount				$ 197.6
Percentage of par (as a percent)				98.80%
Discount				$ 2.4
Discount percentage (as a percent)				1.20%
Senior Secured Incremental Term Loan Facility | Secured Debt
Debt Instrument [Line Items]
Debt extinguished	$ 348.3	340.1
Loss on extinguishment of debt		9.1
Face amount		$ 349.1	$ 350
Issue amount			$ 340.5
Percentage of par (as a percent)		98.90%	97.30%
Discount		$ 4	$ 9.5
Discount percentage (as a percent)			2.70%

Debt - Term Loans (Details)

Debt - Term Loans (Details) $ in Thousands	Jun. 30, 2021USD ($)loaninstallment	Jun. 30, 2021USD ($)loaninstallment	Jul. 01, 2019loan
Debt Instrument [Line Items]
Deferred financing costs	$ 349	$ 349
Outstanding principal balance	$ 50,000	$ 50,000
Secured Debt
Debt Instrument [Line Items]
Number of term loans | loan			2
Secured Debt | Five-year Term Loans Maturing 2021
Debt Instrument [Line Items]
Number of term loans | loan	3	3
Debt instrument, term	5 years	5 years
Face amount	$ 3,300	$ 3,300
Number of installments | installment	8	8
Installment payment, percentage of initial principal amount (as a percent)	12.50%	12.50%
Deferred financing costs	$ 0	$ 0
Secured Debt | Five-year Term Loans Maturing 2021 | London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate (as a percent)		3.10%
Secured Debt | One-year Term Loans Maturing 2019
Debt Instrument [Line Items]
Number of term loans | loan	2	2
Debt instrument, term		1 year
Face amount	$ 3,200	$ 3,200
Secured Debt | One-year Term Loans Maturing 2019, Loan One
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage (as a percentage)	4.56%	4.56%
Secured Debt | One-year Term Loans Maturing 2019, Loan Two
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage (as a percentage)	4.35%	4.35%

Debt - Additional Information (

Debt - Additional Information (Details) - USD ($) $ in Thousands	Jul. 01, 2019	Feb. 15, 2019	Jun. 30, 2021	Oct. 04, 2017
Debt Instrument [Line Items]
Deferred financing costs			$ 349
Senior Secured Term Loan Facility | Secured Debt
Debt Instrument [Line Items]
Prepayments as a percentage of the preceding year excess cash flow (as a percent)			50.00%
Deferred financing costs			$ 300
Weighted average interest rate (as a percent)			2.80%
Interest expense			$ 1,300
Deferred financing costs amortization			$ 200
Interest rate above applicable rate (as a percent)				2.00%
Debt extinguished	$ 147,000
Senior Secured Incremental Term Loan Facility | Secured Debt
Debt Instrument [Line Items]
Debt extinguished	$ 348,300	$ 340,100

Debt - Long-term Debt - Future

Debt - Long-term Debt - Future Minimum Principal Payment Obligations (Details) $ in Thousands	Jun. 30, 2021USD ($)
Long-term Debt, Fiscal Year Maturity [Abstract]
2025	$ 50,000
Total outstanding principal balance	50,000
Unamortized deferred financing costs	(349)
Long-term debt	$ 49,651

Debt - Long-term Debt - Current

Debt - Long-term Debt - Current and Non-current (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Sep. 30, 2020
Long-term Debt, by Current and Noncurrent [Abstract]
Long-term debt	$ 49,651
Current portion of long-term debt		$ 827
Non-current portion of long-term debt	$ 49,651	$ 49,588

Leases - Operating Lease Expens

Leases - Operating Lease Expense (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Lease, Cost [Abstract]
Operating lease costs	$ 2,878	$ 2,358	$ 8,135	$ 6,755
Amortization of assets	182	311	745	933
Interest on lease liabilities	10	29	31	84
Total finance lease costs	192	340	776	1,017
Variable lease cost	514	448	1,578	1,314
Short-term lease costs	123	181	349	477
Total lease costs	$ 3,707	$ 3,327	$ 10,838	$ 9,563

Leases - Assets and Liabilities

Leases - Assets and Liabilities - Operating Leases (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Sep. 30, 2020
Assets and Liabilities, Lessee [Abstract]
Operating lease right-of-use assets	$ 52,159	$ 39,071
Accrued expenses and other current liabilities	$ 7,489	$ 7,015
Operating Lease, Liability, Current, Statement of Financial Position	Accrued expenses and other current liabilities	Accrued expenses and other current liabilities
Long-term operating lease liabilities	$ 45,034	$ 31,855
Total lease liability balance	$ 52,523	$ 38,870

Leases - Assets and Liabiliti_2

Leases - Assets and Liabilities - Finance Leases (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Sep. 30, 2020
Finance Lease, Right-of-Use Asset, after Accumulated Amortization [Abstract]
Property, plant and equipment, at cost	$ 2,252	$ 2,540
Accumulated amortization	(1,989)	(1,246)
Property, plant and equipment, net	$ 263	$ 1,294
Finance Lease, Right-of-Use Asset, Statement of Financial Position	Property, plant and equipment, net	Property, plant and equipment, net
Finance Lease Liability [Abstract]
Accrued expenses and other current liabilities	$ 610	$ 1,135
Finance Lease, Liability, Current, Statement of Financial Position	Accrued expenses and other current liabilities	Accrued expenses and other current liabilities
Other long-term liabilities		$ 348
Other long-term liabilities, net	$ (10)
Finance Lease, Liability, Noncurrent, Statement of Financial Position		Other long-term liabilities
Total finance lease liabilities	$ 600	$ 1,483

Leases - Additional Information

Leases - Additional Information (Details)	Jun. 30, 2021	Sep. 30, 2020
Leases [Abstract]
Weighted average remaining lease term, operating leases	10 years 8 months 23 days	8 years 8 months 19 days
Weighted average remaining lease term, finance leases	8 months 15 days	1 year 3 months 25 days
Weighted average discount rate, operating leases (as a percent)	4.02%	3.92%
Weighted average discount rate, finance leases (as a percent)	4.81%	4.73%

Leases - Supplemental Cash Flow

Leases - Supplemental Cash Flow Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Cash Flow, Operating Activities, Lessee [Abstract]
Operating cash flows from operating leases	$ 2,532	$ 2,215	$ 7,530	$ 6,089
Operating cash flows from finance leases	8	22	35	77
Financing cash flows from finance leases	$ 269	$ 297	$ 881	$ 880

Leases - Assets Obtained in Exc

Leases - Assets Obtained in Exchange for Lease Liabilities (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Lessee Disclosure [Abstract]
ROU assets obtained in exchange for lease liabilities, operating leases	$ 14,066	$ 3,026	$ 19,033	$ 13,753

Leases - Future Lease Payments

Leases - Future Lease Payments - Operating Leases (Details) $ in Thousands	Jun. 30, 2021USD ($)
Lessee, Operating Lease, Liability, Payment, Due [Abstract]
2021	$ 2,501
2022	9,032
2023	7,286
2024	6,378
2025	5,779
Thereafter	34,475
Total future lease payments	$ 65,451

Leases - Gross Difference - Ope

Leases - Gross Difference - Operating Leases (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Sep. 30, 2020
Operating Lease Liabilities, Gross Difference, Amount [Abstract]
Total future lease payments	$ 65,451
Less imputed interest	(12,928)
Total lease liability balance	$ 52,523	$ 38,870

Leases - Future Lease Payment_2

Leases - Future Lease Payments - Finance Leases (Details) $ in Thousands	Jun. 30, 2021USD ($)
Finance Lease, Liability, Payment, Due [Abstract]
2021	$ 251
2022	363
Total future lease payments	$ 614

Leases - Gross Difference - Fin

Leases - Gross Difference - Finance Leases (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Sep. 30, 2020
Finance Lease Liabilities, Gross Difference, Amount [Abstract]
Total future lease payments	$ 614
Less imputed interest	(14)
Total finance lease liabilities	$ 600	$ 1,483

Leases - Future Lease Payment_3

Leases - Future Lease Payments Not Commenced (Details) $ in Millions	Jun. 30, 2021USD ($)
Leases [Abstract]
Leases that have not commenced with future lease payments	$ 15.1

Income Taxes - Provision (Benef

Income Taxes - Provision (Benefit) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Income Tax Expense (Benefit), Continuing Operations [Abstract]
Income tax expense (benefit)	$ 9,370	$ 5,120	$ 20,428	$ 5,557
Benefit from reversal of uncertain tax positions	$ 1,500
Benefit related to stock compensation windfalls			$ 2,700	6,100
Benefit from a reduction of deferred tax liabilities related to the extension of a tax rate incentive in China				$ 500

Income Taxes - Unrecognized Tax

Income Taxes - Unrecognized Tax Benefits - General Information (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
	Jun. 30, 2021	Jun. 30, 2021
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense [Abstract]
Interest related to unrecognized benefits	$ 0.3	$ 0.8

Income Taxes - Unrecognized T_2

Income Taxes - Unrecognized Tax Benefits - Reasonably Possible Change (Details) $ in Millions	Jun. 30, 2021USD ($)
Income Tax Disclosure [Abstract]
Anticipated unrecognized tax benefit reduction during next twelve months	$ 17.2

Other Balance Sheet Informati_3

Other Balance Sheet Information - Summary of Account Receivable (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Sep. 30, 2020
Valuation and Qualifying Accounts Disclosure [Line Items]
Accounts receivable	$ 238,890	$ 195,587
Less allowance for expected credit losses	(4,737)	(7,216)
Accounts receivable, net	234,079	188,291
Allowance for Sales Returns
Valuation and Qualifying Accounts Disclosure [Line Items]
Less allowance for sales returns	$ (74)	$ (80)

Other Balance Sheet Informati_4

Other Balance Sheet Information - Summary of Inventories (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Sep. 30, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Raw materials and purchased parts	$ 98,997	$ 73,609
Work-in-process	21,356	16,461
Finished goods	34,367	24,764
Inventory, net	154,720	114,834
Reserves for excess and obsolete inventory	$ 18,600	$ 17,100

Other Balance Sheet Informati_5

Other Balance Sheet Information - Capitalized Direct Costs (Details) - USD ($) $ in Millions	9 Months Ended
	Jun. 30, 2021	Sep. 30, 2020
Property, Plant and Equipment, Gross [Abstract]
Capitalized computer software, gross	$ 21.9	$ 18.2
Capitalized computer software costs	3.7
Software Development
Property, Plant and Equipment, Gross [Abstract]
Capitalized computer software, gross	$ 5

Other Balance Sheet Informati_6

Other Balance Sheet Information - Product Warranty and Retrofit Activity on Gross Basis (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Movement in Standard and Extended Product Warranty Accrual, Increase (Decrease) [Roll Forward]
Beginning Balance	$ 8,044	$ 7,910	$ 8,201	$ 7,175
Accruals for warranties	1,892	1,380	5,990	6,033
Costs incurred	(1,804)	(1,409)	(6,059)	(5,327)
Ending Balance	$ 8,132	$ 7,881	$ 8,132	$ 7,881

Stock-Based Compensation - Stoc

Stock-Based Compensation - Stock-Based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation	$ 6,086	$ 3,725	$ 20,277	$ 12,348
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation	5,475	3,348	18,667	11,361
Employee Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation	$ 611	$ 377	$ 1,610	$ 987

Stock-Based Compensation - Rest

Stock-Based Compensation - Restricted Stock Units Granted - Tabular Disclosure (Details) - shares	9 Months Ended
	Jun. 30, 2021	Jun. 30, 2020
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stocks granted (in shares)	346,172	411,967
Restricted Stock, Time Based Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stocks granted (in shares)	162,842	163,390
Board of Director Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stocks granted (in shares)	14,683	27,007
Restricted Stock, Performance Based Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stocks granted (in shares)	168,647	221,570

Stock-Based Compensation - Time

Stock-Based Compensation - Time-Based Grants (Details) - Restricted Stock, Time Based Shares	9 Months Ended
	Jun. 30, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (in years)	3 years
Share-based Compensation Award, Tranche One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage (as a percent)	33.33%
Share-based Compensation Award, Tranche Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage (as a percent)	33.33%
Share-based Compensation Award, Tranche Three
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage (as a percent)	33.33%

Stock-Based Compensation - Perf

Stock-Based Compensation - Performance-Based Grants (Details)	9 Months Ended	12 Months Ended
	Jun. 30, 2021	Sep. 30, 2020	Sep. 30, 2019
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Performance-based awards granted, percentage (as a percent)	100.00%	100.00%	100.00%
Performance-based awards granted, percentage, maximum threshold met (as a percent)	200.00%	200.00%	200.00%
Performance goal measurement period (in years)	3 years

Stock-Based Compensation - Re_2

Stock-Based Compensation - Restricted Stock Unit Activity - Tabular Disclosure (Details) - Restricted Stock Units (RSUs) - $ / shares	3 Months Ended		9 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Shares
Outstanding at beginning of period (in shares)			1,183,009
Restricted stocks granted (in shares)			346,172	411,967
Vested (in shares)			(406,764)
Forfeited (in shares)			(32,600)
Outstanding at end of period (in shares)	1,089,817		1,089,817
Weighted Average Grant-Date Fair Value
Outstanding at beginning of period (in dollars per share)			$ 36.10
Granted (in dollars per share)	$ 104.54	$ 31.87	71.81	$ 46.52
Vested (in dollars per share)			36.01
Forfeited (in dollars per share)			44.27
Outstanding at end of period (in dollars per share)	$ 47.23		$ 47.23

Stock-Based Compensation - Re_3

Stock-Based Compensation - Restricted Stock Unit Activity - Additional Information (Details) - Restricted Stock Units (RSUs) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in dollars per share)	$ 104.54	$ 31.87	$ 71.81	$ 46.52
Fair value of restricted stock awards vested	$ 0.3	$ 0.2	$ 28.2	$ 41.6
Proceeds from employees to satisfy tax obligation			$ 9.7	$ 24.1

Stock-Based Compensation - Re_4

Stock-Based Compensation - Restricted Stock Unit Activity - Unrecognized Compensation Cost (Details) - Restricted Stock Units (RSUs) $ in Millions	9 Months Ended
	Jun. 30, 2021USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost	$ 29.1
Unrecognized compensation cost, estimated weighted average amortization period	1 year 8 months 12 days

Stock-Based Compensation - Empl

Stock-Based Compensation - Employee Stock Purchase Plan (Details) - shares	9 Months Ended
	Jun. 30, 2021	Jun. 30, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued under employee stock purchase plan (in shares)	58,124	63,934
Employee Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Purchase price of common stock (as a percent)	85.00%

Earnings per Share - Tabular Di

Earnings per Share - Tabular Disclosure (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Net income
Income from continuing operations	$ 39,170	$ 13,696	$ 90,110	$ 36,062
Loss from discontinued operations, net of tax	(4)		(1,168)	(182)
Net income	39,166	13,696	88,942	35,880
Net income attributable to Brooks Automation, Inc. - basic	39,166	13,696	88,942	35,880
Net income attributable to Brooks Automation, Inc. - diluted	$ 39,166	$ 13,696	$ 88,942	$ 35,880
Weighted average common shares outstanding used in computing diluted earnings per share
Weighted average common shares outstanding used in computing basic earnings per share (in shares)	74,296	73,759	74,195	73,473
Dilutive restricted stock units	199	101	225	293
Weighted average common shares outstanding used in computing diluted earnings per share (in shares)	74,495	73,860	74,420	73,766
Basic net income per share:
Income from continuing operations (in dollars per share)	$ 0.53	$ 0.19	$ 1.21	$ 0.49
Loss from discontinued operations, net of tax (in dollars per share)	0		(0.02)	0
Basic net income per share attributable to Brooks Automation, Inc. (in dollars per share)	0.53	0.19	1.20	0.49
Diluted net income per share:
Income from continuing operations (in dollars per share)	0.53	0.19	1.21	0.49
Loss from discontinued operations, net of tax (in dollars per share)	0		(0.02)	0
Diluted net income per share (in dollars per share)	0.53	0.19	1.20	0.49
Dividend declared per share (in dollars per share)	$ 0.10	$ 0.10	$ 0.30	$ 0.30

Earnings per Share - Anti-dilut

Earnings per Share - Anti-dilutive Securities (Details) - shares	3 Months Ended		9 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Restricted Stock Units (RSUs)
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of diluted earnings per share (in shares)	13,593	148,085	18,548	162,189

Revenue from Contracts with C_3

Revenue from Contracts with Customers - Segment Information (Details) - segment	3 Months Ended		9 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Segment Reporting Information [Line Items]
Number of operating segments	3	3	3	3
Number of reportable segments	3	3	3	3
Number of reporting units	5	5	5	5
Brooks Semiconductor Solutions Group
Segment Reporting Information [Line Items]
Number of reporting units	3	3	3	3
Brooks Life Sciences Products
Segment Reporting Information [Line Items]
Number of reporting units	1	1	1	1
Brooks Life Sciences Services
Segment Reporting Information [Line Items]
Number of reporting units	1	1	1	1

Revenue from Contracts with C_4

Revenue from Contracts with Customers - Disaggregated By Reporting Unit (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Disaggregation of Revenue [Line Items]
Total revenue	$ 315,349	$ 220,350	$ 851,439	$ 651,077
Automation Solutions
Disaggregation of Revenue [Line Items]
Total revenue	$ 122,567	$ 81,656	$ 320,540	$ 214,627
Reporting unit, name of segment	Brooks Semiconductor Solutions Group	Brooks Semiconductor Solutions Group	Brooks Semiconductor Solutions Group	Brooks Semiconductor Solutions Group
Contamination Control Solutions
Disaggregation of Revenue [Line Items]
Total revenue	$ 50,742	$ 34,780	$ 117,236	$ 124,584
Reporting unit, name of segment	Brooks Semiconductor Solutions Group	Brooks Semiconductor Solutions Group	Brooks Semiconductor Solutions Group	Brooks Semiconductor Solutions Group
Global Semiconductor Services
Disaggregation of Revenue [Line Items]
Total revenue	$ 12,953	$ 10,616	$ 36,898	$ 31,575
Reporting unit, name of segment	Brooks Semiconductor Solutions Group	Brooks Semiconductor Solutions Group	Brooks Semiconductor Solutions Group	Brooks Semiconductor Solutions Group
Brooks Life Sciences Products
Disaggregation of Revenue [Line Items]
Total revenue	$ 48,625	$ 30,421	$ 146,490	$ 91,138
Reporting unit, name of segment	Brooks Life Sciences Products	Brooks Life Sciences Products	Brooks Life Sciences Products	Brooks Life Sciences Products
Brooks Life Sciences Services
Disaggregation of Revenue [Line Items]
Total revenue	$ 80,462	$ 62,877	$ 230,275	$ 189,153
Reporting unit, name of segment	Brooks Life Sciences Services	Brooks Life Sciences Services	Brooks Life Sciences Services	Brooks Life Sciences Services
Brooks Semiconductor Solutions Group
Disaggregation of Revenue [Line Items]
Total revenue	$ 186,262	$ 127,052	$ 474,674	$ 370,786

Revenue from Contracts with C_5

Revenue from Contracts with Customers - Contract Balances (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Sep. 30, 2020
Accounts Receivable, after Allowance for Credit Loss, Current [Abstract]
Accounts receivable, net	$ 234,079		$ 234,079		$ 188,291
Contract with Customer, Asset, after Allowance for Credit Loss, Current [Abstract]
Contract assets	$ 16,100		$ 16,100		16,800
Capitalized Contract Cost [Abstract]
Sales commission amortization period	60 months		60 months
Deferred commissions	$ 300		$ 300		400
Deferred commission amortization expense		$ 100	100	$ 400
Contract with Customer, Liability [Abstract]
Current contract liabilities	35,421		35,421		31,357
Contract liabilities	35,400		$ 35,400		$ 31,400
Revenue recognized	30,200
Maximum
Capitalized Contract Cost [Abstract]
Deferred commission amortization expense	$ 100

Revenue from Contracts with C_6

Revenue from Contracts with Customers - Remaining Performance Obligations (Details) $ in Thousands	Jun. 30, 2021USD ($)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligations	$ 65,229
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-07-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligations	$ 46,552
Unsatisfied performance obligation, period	12 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-07-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligations	$ 18,677
Unsatisfied performance obligation, period

Revenue from Contracts with C_7

Revenue from Contracts with Customers - Costs to Obtain and Fulfill a Contract (Details)	Jun. 30, 2021
Capitalized Contract Cost [Abstract]
Sales commission amortization period	60 months

Segment Information - General I

Segment Information - General Information (Details) - segment	3 Months Ended		9 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Segment Reporting, Disclosure of Entity's Reportable Segments [Abstract]
Number of reportable segments	3	3	3	3
Number of operating segments	3	3	3	3
Number of reportable segments, previously operated	2	2	2	2

Segment Information - Reconcili

Segment Information - Reconciliation of Reportable Segment Operating Income (Loss) to Corresponding Consolidated Amounts (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Segment Reporting Information [Line Items]
Total revenue	$ 315,349	$ 220,350	$ 851,439	$ 651,077
Amortization of other intangible assets			30,800	31,300
Restructuring charges		(29)	179	1,125
Tariff adjustment			5,414
Operating income	50,233	19,099	111,667	44,337
Interest income	409	29	503	865
Interest expense	(477)	(810)	(1,485)	(2,265)
Other income (expenses), net	(1,625)	498	(147)	(1,318)
Income before income taxes	48,540	18,816	110,538	41,619
Completed Technology
Segment Reporting Information [Line Items]
Amortization of other intangible assets	3,352	2,779	8,060	8,194
Acquired Intangible Assets
Segment Reporting Information [Line Items]
Amortization of other intangible assets	7,733	7,611	22,690	23,137
Brooks Semiconductor Solutions Group
Segment Reporting Information [Line Items]
Total revenue	186,262	127,052	474,674	370,786
Operating income	44,797	23,414	99,637	55,120
Brooks Life Sciences Products
Segment Reporting Information [Line Items]
Total revenue	48,625	30,421	146,490	91,138
Operating income	9,138	2,482	28,295	4,988
Brooks Life Sciences Services
Segment Reporting Information [Line Items]
Total revenue	80,462	62,877	230,275	189,153
Operating income	13,783	4,109	41,501	15,695
Operating Segments
Segment Reporting Information [Line Items]
Total revenue	315,349	220,350	851,439	651,077
Segment Reconciling Items
Segment Reporting Information [Line Items]
Operating income	67,718	30,005	169,433	75,803
Corporate, Non-Segment
Segment Reporting Information [Line Items]
Other unallocated corporate expense (income)	$ 6,400	$ 545	$ 21,423	$ (990)

Segment Information - Financial

Segment Information - Financial Information for Business Segments - Assets (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Sep. 30, 2020
Segment Reporting Information [Line Items]
Total assets	$ 1,763,255	$ 1,559,125
Operating Segments
Segment Reporting Information [Line Items]
Total assets	1,472,498	1,248,452
Operating Segments | Brooks Semiconductor Solutions Group
Segment Reporting Information [Line Items]
Total assets	433,108	296,289
Operating Segments | Brooks Life Sciences Products
Segment Reporting Information [Line Items]
Total assets	259,592	214,196
Operating Segments | Brooks Life Sciences Services
Segment Reporting Information [Line Items]
Total assets	$ 779,798	$ 737,967

Segment Information - Reconci_2

Segment Information - Reconciliation of Reportable Segment Assets to Corresponding Consolidated Amounts (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Sep. 30, 2020
Segment Reporting Information [Line Items]
Cash and cash equivalents, restricted cash, and marketable securities	$ 286,310	$ 305,694
Deferred tax asset	4,447	4,979
Assets	1,763,255	1,559,125
Operating Segments
Segment Reporting Information [Line Items]
Assets	$ 1,472,498	$ 1,248,452

Segment Information - Revenue f

Segment Information - Revenue from External Customers Attributed to Geographic Areas (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	$ 315,349	$ 220,350	$ 851,439	$ 651,077
Asia/Pacific/Other
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	151,086	99,415	395,138	307,969
CHINA
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	55,062	30,228	137,945	76,435
TAIWAN, PROVINCE OF CHINA
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	29,844	15,266	73,350	91,993
KOREA, REPUBLIC OF
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	28,994	22,369	77,982	46,296
Asia Pacific, Other than China, Taiwan, and Korea
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	37,186	31,552	105,861	93,245
North America
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	110,454	79,882	313,830	246,000
UNITED STATES
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	108,344	79,032	290,883	243,883
North America, Other than United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	2,110	850	22,947	2,117
Europe
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	$ 53,809	$ 41,053	$ 142,471	$ 97,108

Significant Customers (Details)

Significant Customers (Details) - Largest Customer	9 Months Ended
	Jun. 30, 2021	Jun. 30, 2020
Customer Concentration Risk | Revenue from Contract with Customer Benchmark
Concentration Risk [Line Items]
Concentration risk, percentage (as a percent)		11.00%
Credit Concentration Risk | Accounts Receivable
Concentration Risk [Line Items]
Concentration risk, percentage (as a percent)	11.00%

Commitments and Contingencies -

Commitments and Contingencies - Tariff Matter (Details) $ / shares in Units, $ in Millions	3 Months Ended	9 Months Ended
	Jun. 30, 2021USD ($)$ / shares	Jun. 30, 2021USD ($)$ / shares
Loss Contingency Accrual, Disclosures [Abstract]
Earnings Per Share, Basic, Increase (Decrease) During Period, Change in Estimate, Tariffs | $ / shares	$ (0.07)	$ (0.07)
Earnings Per Share, Diluted, Increase (Decrease) During Period, Change in Estimate, Tariffs | $ / shares	$ (0.07)	$ (0.07)
Tariffs
Loss Contingency Accrual, Disclosures [Abstract]
Loss contingency accrual	$ 6.1	$ 6.1
Tariffs, Period Prior to Acquisition
Loss Contingency Accrual, Disclosures [Abstract]
Loss contingency accrual	2.8	2.8
Tariffs, Period after Acquisition
Loss Contingency Accrual, Disclosures [Abstract]
Loss contingency accrual	$ 3.3	$ 3.3

Commitments and Contingencies_2

Commitments and Contingencies - Letters of Credit (Details) $ in Millions	Jun. 30, 2021USD ($)
Commitments and Contingencies Disclosure [Abstract]
Outstanding letters of credit	$ 1.3

Commitments and Contingencies_3

Commitments and Contingencies - Purchase Commitments (Details) $ in Millions	Jun. 30, 2021USD ($)
Non-cancelable commitments
Other Commitments [Line Items]
Other commitment	$ 288
Non-cancellable Contracts and Purchase Orders for Inventory
Other Commitments [Line Items]
Other commitment	254.6
Non-cancelable IT-related commitments
Other Commitments [Line Items]
Other commitment	18
Non-cancelable China facility commitments
Other Commitments [Line Items]
Other commitment	$ 15.2

Subsequent Events (Details)

Subsequent Events (Details) - $ / shares	3 Months Ended			9 Months Ended
	Sep. 30, 2021	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Subsequent Event [Line Items]
Cash dividend declared (in dollars per share)		$ 0.10	$ 0.10	$ 0.30	$ 0.30
Subsequent Event
Subsequent Event [Line Items]
Cash dividend declared, date	Aug. 3, 2021
Cash dividend declared (in dollars per share)	$ 0.10
Cash dividend declared, payment date	Sep. 24, 2021
Cash dividend declared, record date	Sep. 3, 2021