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

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Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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Amount, after accumulated amortization, of debt discount.

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Amount of the cost of borrowed funds accounted for as interest expense for debt.

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Public Notes (Details) - USD ($)										3 Months Ended
Public Notes (Details) - USD ($)	Sep. 23, 2022	Sep. 19, 2022	Sep. 30, 2021	May 27, 2021	Feb. 19, 2021	Jan. 22, 2021	Oct. 01, 2018	Jun. 20, 2018	Mar. 15, 2013	Sep. 30, 2022	Sep. 30, 2021	Jun. 30, 2022	Dec. 05, 2018
Debt Instrument [Line Items]
Net realized (losses) on extinguishment of debt										$ (28,000)	$ (5,357,000)
Debt financing costs										15,223,000		$ 10,801,000
Public Notes
Debt Instrument [Line Items]
Issuance of debt										0	294,798,000
Unsecured debt outstanding										$ 1,344,169,000		1,343,178,000
6.375% 2024 Notes
Debt Instrument [Line Items]
Stated rate										6.375%
3.364% 2026 Notes
Debt Instrument [Line Items]
Stated rate										3.364%
3.437% 2028 Notes
Debt Instrument [Line Items]
Stated rate										3.437%
Unsecured Debt
Debt Instrument [Line Items]
Unamortized discount										$ 10,605,000		11,234,000
Unsecured Debt \| Public Notes
Debt Instrument [Line Items]
Unamortized discount			$ 15,802,000								15,802,000
Debt issuance costs, gross			17,834,000								17,834,000
Debt financing costs										10,338,000		11,047,000
Interest expense										15,613,000	13,932,000
Unsecured Debt \| 2023 Notes
Debt Instrument [Line Items]
Face amount								$ 70,000,000	$ 250,000,000
Stated rate								5.875%	5.875%
Issuance of debt								$ 69,403,000	$ 243,641,000
Repurchased face amount		$ 284,219,000
Redemption price rate		98.00%
Repayments of long-term debt	$ 347,000
Net realized (losses) on extinguishment of debt										(6,000)
Unsecured debt outstanding										$ 283,872,000		$ 284,219,000
Unsecured Debt \| 6.375% 2024 Notes
Debt Instrument [Line Items]
Face amount							$ 100,000,000
Stated rate							6.375%			637.50%		637.50%
Issuance of debt							$ 98,985,000
Unsecured debt outstanding										$ 81,240,000		$ 81,240,000
Unsecured Debt \| 2026 Notes
Debt Instrument [Line Items]
Face amount					$ 75,000,000	$ 325,000,000
Stated rate						3.706%							3.706%
Issuance of debt					$ 74,061,000	$ 317,720,000
Unsecured debt outstanding										$ 400,000,000		$ 400,000
Unsecured Debt \| 3.364% 2026 Notes
Debt Instrument [Line Items]
Face amount				$ 300,000
Stated rate				3.364%						336.40%		336.40%
Issuance of debt				$ 293,283,000
Unsecured debt outstanding										$ 300,000,000		$ 300,000
Unsecured Debt \| 3.437% 2028 Notes
Debt Instrument [Line Items]
Face amount			$ 300,000,000								$ 300,000,000
Stated rate			3.437%							343.70%	3.437%	343.70%
Issuance of debt			$ 291,798,000
Unsecured debt outstanding										$ 300,000,000		$ 300,000