Share-based Compensation - Restricted Stock and Performance-based Restrcited Stock Activity (Details) - USD ($)	3 Months Ended	12 Months Ended
Sep. 30, 2018	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2018
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Allocated share-based compensation expense		$ 15,324,000	$ 10,454,000	$ 13,177,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]
Weighted Average Remaining Recognition Period (Years)		2 years
Market-based Restricted Stock Units (MSU)
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Allocated share-based compensation expense		$ 1,200,000	$ 600,000	$ 400,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Granted (in shares)	1,300,000
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Nonvested (in shares)	919,023	932,138	906,341	919,023
Granted (in shares)		722,873	505,440	527,022
Vested (in shares)		(567,087)	(455,893)	(499,954)
Forfeited (in shares)		(34,400)	(23,750)	(39,750)
Nonvested (in shares)		1,053,524	932,138	906,341	919,023
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]
Nonvested (in dollars per share)	$ 15.14	$ 11.36	$ 14.09	$ 15.14
Granted (in dollars per share)		29.85	8.51	11.28
Vested (in dollars per share)		15.70	13.53	13.09
Forfeited (in dollars per share)		14.88	13.19	13.82
Nonvested (in dollars per share)		$ 21.60	$ 11.36	$ 14.09	$ 15.14
Weighted Average Remaining Recognition Period (Years)		1 year 8 months 23 days	1 year 7 months 28 days	1 year 7 months 13 days	1 year 7 months 13 days
Aggregate intrinsic value, nonvested		$ 32,016,594	$ 10,141,661	$ 8,465,225	$ 13,086,888
Performance Based Restricted Stock Units (PRSUs)
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Allocated share-based compensation expense		$ 2,300,000	$ 1,500,000	$ 2,800,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Nonvested (in shares)	422,300	342,775	596,724	422,300
Granted (in shares)		165,500	155,000	291,750
Vested (in shares)		(148,211)	(110,659)	(111,623)
Forfeited (in shares)		(6,240)	(298,290)	(5,703)
Nonvested (in shares)		353,824	342,775	596,724	422,300
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]
Nonvested (in dollars per share)	$ 16.63	$ 12.38	$ 13.95	$ 16.63
Granted (in dollars per share)		36.27	7.36	11.18
Vested (in dollars per share)		14.24	16.68	16.68
Forfeited (in dollars per share)		17.23	11.32	16.78
Nonvested (in dollars per share)		$ 22.69	$ 12.38	$ 13.95	$ 16.63
Weighted Average Remaining Recognition Period (Years)		1 year 8 months 26 days	1 year 7 months 6 days	1 year 10 months 17 days	2 years 21 days
Aggregate intrinsic value, nonvested		$ 10,752,711	$ 3,729,392	$ 5,573,402	$ 6,013,552

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Intrinsic value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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