Debt (Long-term debt) (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Jun. 30, 2021	Sep. 30, 2020
Total Debt:
Long-term Debt, Gross	$ 1,650,000	$ 1,091,000	$ 293,250
Total Amount Outstanding	1,606,418	1,070,711	288,621
Less Current Portion:
Current Portion	(6,375)	(3,000)	(3,000)
Noncurrent Portion	1,600,043	1,067,711	285,621
Senior Secured Notes Due 2028 And Term B Loan [Member]
Total Debt:
Unamortized debt issuance costs	(43,582)	(20,289)	(4,629)
Senior Secured Notes Due 2028 [Member]
Total Debt:
Long-term Debt, Gross	800,000	800,000
Term B Loan [Member]
Total Debt:
Long-term Debt, Gross	850,000	0
Less Current Portion:
Current Portion	(6,375)	0
Prior Term Loan B [Member]
Total Debt:
Long-term Debt, Gross	0	291,000	293,250
Less Current Portion:
Current Portion	$ 0	$ (3,000)	$ (3,000)

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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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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