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The current portion of long term debt gross value.

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The carrying amount of long-term debt, excluding amounts to be repaid within one year or the normal operating cycle, if longer (current maturities).

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Amount, after accumulated amortization, of debt discount (premium).

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LONG-TERM DEBT - Summary of Long-Term Debt (Details) £ in Thousands, $ in Thousands	Mar. 31, 2023 USD ($)	Mar. 31, 2023 GBP (£)	Sep. 30, 2022 USD ($)	Jun. 22, 2020
Debt Instrument [Line Items]
Long-term debt, Outstanding Balance	$ 1,527,168		$ 1,595,560
less: Current portion, Outstanding Balance	(15,720)		(12,653)
Long-term debt, Outstanding Balance, Non-current	1,511,448		1,582,907
Original Issuer Premium/(Discount)	(816)		(878)
Capitalized Fees & Expenses	(19,068)		(21,031)
Long-term debt, Balance Sheet	1,507,284		1,573,651
less: Current portion, Balance Sheet	(15,720)		(12,653)
Long-term debt, Balance Sheet, Non-current	1,491,564		1,560,998
Senior notes due 2028
Debt Instrument [Line Items]
Long-term debt, Outstanding Balance	974,775		974,775
Original Issuer Premium/(Discount)	242		266
Capitalized Fees & Expenses	(9,930)		(10,939)
Long-term debt, Balance Sheet	$ 965,087		$ 964,102
Coupon Interest Rate	5.75%	5.75%	5.75%	5.75%
Term Loan B due 2029
Debt Instrument [Line Items]
Long-term debt, Outstanding Balance	$ 492,000		$ 496,000
Original Issuer Premium/(Discount)	(1,058)		(1,144)
Capitalized Fees & Expenses	(8,120)		(8,823)
Long-term debt, Balance Sheet	482,822		486,033
Revolver due 2025
Debt Instrument [Line Items]
Long-term debt, Outstanding Balance	30,880		97,328
Original Issuer Premium/(Discount)	0		0
Capitalized Fees & Expenses	(982)		(1,227)
Long-term debt, Balance Sheet	29,898		96,101
Finance lease - real estate
Debt Instrument [Line Items]
Long-term debt, Outstanding Balance	12,406		13,091
Original Issuer Premium/(Discount)	0		0
Capitalized Fees & Expenses	0		0
Long-term debt, Balance Sheet	12,406		13,091
Non US lines of credit
Debt Instrument [Line Items]
Long-term debt, Outstanding Balance	2,924	£ 2,368	0
Original Issuer Premium/(Discount)	0		0
Capitalized Fees & Expenses	(11)		(2)
Long-term debt, Balance Sheet	2,913		(2)
Non US term loans
Debt Instrument [Line Items]
Long-term debt, Outstanding Balance	12,323		12,090
Original Issuer Premium/(Discount)	0		0
Capitalized Fees & Expenses	(13)		(27)
Long-term debt, Balance Sheet	12,310		12,063
Other long term debt
Debt Instrument [Line Items]
Long-term debt, Outstanding Balance	1,860		2,276
Original Issuer Premium/(Discount)	0		0
Capitalized Fees & Expenses	(12)		(13)
Long-term debt, Balance Sheet	$ 1,848		$ 2,263