Consolidated Balance Sheets (Parenthetical) - USD ($) shares in Thousands	Mar. 31, 2020	Jun. 30, 2019
Preferred stock, par value (dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized	45,000	45,000
Preferred stock, shares outstanding	0	0
Treasury stock, shares	20,751	2,972
Commitments and contingencies (see Note 9)
Class A Common Stock [Member]
Common stock, par value (dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized	360,000	360,000
Common stock, shares outstanding	43,508	61,287
Class B Common Stock [Member]
Common stock, par value (dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized	90,000	90,000
Common stock, shares outstanding	13,589	13,589

Represents the caption on the face of the balance sheet to indicate that the entity has entered into (1) purchase or supply arrangements that will require expending a portion of its resources to meet the terms thereof, and (2) is exposed to potential losses or, less frequently, gains, arising from (a) possible claims against a company's resources due to future performance under contract terms, and (b) possible losses or likely gains from uncertainties that will ultimately be resolved when one or more future events that are deemed likely to occur do occur or fail to occur.

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