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 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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Debt - Summary of Maturities (Details) - USD ($)	Sep. 30, 2021	Jun. 30, 2021	Sep. 30, 2020	Mar. 31, 2017	Dec. 31, 2015	Jun. 30, 2015
Debt Instrument [Line Items]
2022	$ 418,037,000
2023	0
2024	0
2025	0
2026	500,000,000
Thereafter	0
Total before unamortized discount	918,037,000
Less: unamortized discount and issuance costs	(50,113,000)
Total debt	$ 867,924,000		$ 1,536,673,000
Convertible Debentures 1.25% Due 2025
Debt Instrument [Line Items]
Convertible debentures, interest rate	1.25%			1.25%
Convertible Debentures 1.5% Due 2035
Debt Instrument [Line Items]
Convertible debentures, interest rate	1.50%					1.50%
Convertible Debentures 1.0% Due 2035
Debt Instrument [Line Items]
Total before unamortized discount	$ 130,300,000
Convertible debentures, interest rate	1.00%	1.00%			1.00%
Convertible Debentures
Debt Instrument [Line Items]
2022	$ 418,037,000
2023	0
2024	0
2025	0
2026	0
Thereafter	0
Total before unamortized discount	418,037,000
Less: unamortized discount and issuance costs	(45,038,000)
Total debt	372,999,000
Senior Notes
Debt Instrument [Line Items]
2022	0
2023	0
2024	0
2025	0
2026	500,000,000
Thereafter	0
Total before unamortized discount	500,000,000
Less: unamortized discount and issuance costs	(5,075,000)
Total debt	$ 494,925,000