GOODWILL AND OTHER INTANGIBLES - Narrative (Details) - USD ($)	3 Months Ended		6 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Mar. 31, 2022	Mar. 31, 2021
Goodwill and Intangible Assets Disclosure [Abstract]
Carry amount of intangible assets related to foreign currency translation	$ 563,000
Amortization expense	4,470,000	$ 2,407,000	$ 6,857,000	$ 4,759,000
Estimated amortization expense, remainder of fiscal year	13,600,000		13,600,000
Estimated amortization expense, year one	22,100,000		22,100,000
Estimated amortization expense, year two	22,100,000		22,100,000
Estimated amortization expense, year three	22,100,000		22,100,000
Estimated amortization expense, year four	22,100,000		22,100,000
Estimated amortization expense, year five	22,100,000		22,100,000
Estimated amortization expense, thereafter	$ 242,638,000		242,638,000
Goodwill impairment			0
Indefinite-lived intangible asset (excluding goodwill) impairment			$ 0