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Stock-Based Compensation - Additional Disclosures (Details) - USD ($) $ / shares in Units, $ in Thousands	9 Months Ended		12 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Sep. 30, 2021	Sep. 30, 2020	May 17, 2022	May 16, 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Issuance of shares of common stock	$ 5,702	$ 0		$ 0	$ 0
Payments related to tax withholding	$ 1,676	$ 0		0	0
Common stock reserved for future issuance or settlement (in shares)	4,400,000		4,400,000
Share-based Payment Arrangement, Expense	$ 15,763			1,744	606
Post-combination portion
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number						96,650
Pre-combination portion
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number							102,305
Emerson stock-based compensation plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Expense	1,100			$ 1,700	$ 600
Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in dollars per share)			$ 193.70
Total fair value of shares vested from RSU grants			$ 46,600
Total unrecognized compensation cost	69,500		$ 69,500
Total unrecognized compensation cost, period of recognition			2 years 9 months 7 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number							504,386
Restricted Stock Units \| Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number						453,397
Restricted Stock Units \| Post-combination portion
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number						61,898
Restricted Stock Units \| Pre-combination portion
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number							22,422
Restricted Stock Units \| Emerson stock-based compensation plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in dollars per share)			$ 166.30
Share-based Payment Arrangement, Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unrecognized compensation cost	$ 35,300		$ 35,300
Total unrecognized compensation cost, period of recognition			2 years 4 months 9 days
Granted (in dollars per share)			$ 193.55
Total intrinsic value of options exercised			$ 18,700
Issuance of shares of common stock			23,000
Payments related to tax withholding			$ 16,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	1,175,853		1,175,853	0			1,326,860
Share-based Payment Arrangement, Option [Member] \| Share-based Payment Arrangement, Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number						1,165,494
Share-based Payment Arrangement, Option [Member] \| Post-combination portion
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number						34,752
Share-based Payment Arrangement, Option [Member] \| Pre-combination portion
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number							79,883
Share-based Payment Arrangement, Option [Member] \| Emerson stock-based compensation plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in dollars per share)			$ 101.44