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Face (par) amount of debt instrument at time of issuance.

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Gross amount of debt extinguished.

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Amount of gain (loss) from the difference between the repurchase price of a debt instrument initially issued by the entity and the net carrying amount of the debt at the time of its repurchase.

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Long-term debt: Debt extinguishment and redemptions of 2022 Notes (Details) € in Millions				1 Months Ended	3 Months Ended
	Dec. 01, 2021 USD ($)	May 06, 2021 USD ($)	Apr. 06, 2021 USD ($)	Jun. 30, 2020 USD ($)	Mar. 31, 2021 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2021 EUR (€)	May 31, 2021	May 07, 2021 USD ($)	Jun. 30, 2020 EUR (€)	Jun. 30, 2019 EUR (€)	Jun. 25, 2019 EUR (€)
Senior unsecured 2021 notes
Long-term debt
Interest rate (as a percent)				5.625%						5.625%
Principal amount plus accrued and unpaid interest (as a percent)				100.00%
Face amount				$ 189,200,000
Interest				1,600,000
Loss on debt purchase				$ 600,000
Senior unsecured 2024 Notes
Long-term debt
Interest rate (as a percent)				4.375%		4.375%	4.375%			4.375%
Face amount						$ 405,600,000	€ 350.0			€ 215.0	€ 135.0	€ 135.0
Senior notes outstanding						405,600,000	€ 350.0
Senior secured notes due 2022
Long-term debt
Interest rate (as a percent)								5.375%
Principal amount plus accrued and unpaid interest (as a percent)					103.20%
Face amount					$ 115,900,000	$ 284,100,000
Interest					400,000
Loss on debt purchase					$ 3,900,000
Notice issued for redemption of debt			$ 45,000,000.0
Amount of debt redeemed		$ 45,000,000.0	45,000,000.0
Redemption value			$ 1,900,000
Redemption price per $1,000 aggregate principal amount			41.41533
Accrued interest value			$ 400,000
Accrued interest per $1,000 aggregate principal amount			9.70486
Senior notes outstanding		$ 284,100,000
Senior secured notes due 2022 \| Subsequent Event
Long-term debt
Interest	$ 11,500,000
Loss on debt purchase	$ 10,800,000
Senior secured 2026 Notes
Long-term debt
Interest rate (as a percent)						3.50%	3.50%
Face amount						$ 500,000,000.0			$ 500,000,000.0
Senior notes outstanding						$ 500,000,000.0