Stockholders' Equity - Additional Information (Detail) - USD ($)		12 Months Ended
	Aug. 07, 2018	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2015	May 31, 2013
Class of Stock [Line Items]
Number of shares repurchased		0	0	3,100,000
Aggregate cost of shares repurchased		$ 0	$ 0	$ 39,000,000
Number of common share attached to one right		1
Conditions under which rights become exercisable		The rights, unless redeemed or exchanged, will become exercisable for common stock of the Company 10 business days after the earlier of public announcement that a person or group has obtained beneficial ownership (defined to include stock which a person has the right to acquire, regardless of whether such right is subject to the passage of time or the satisfaction of conditions) of 15% or more of the outstanding shares of the Company’s Class B Common Stock or launch of a tender offer to do so. Following such acquisition of beneficial ownership, each right will entitle its holder (other than the acquiring person or group) to purchase, at the exercise price (subject to adjustments provided in the rights agreement), a number of shares of the Company’s Class A or Class B Common Stock, as applicable, having a then-current market value of twice the exercise price, and in the event of a subsequent merger or other acquisition of the Company or transfer of more than 50% of the Company or its assets, to purchase, at the exercise price, a number of shares of common stock of the acquiring entity having a then-current market value of twice the exercise price. The exercise price for the Company rights will be $90.00, subject to certain adjustments.
Exercise price of rights		$ 90.00
Conditions under which rights not become exercisable		The rights will not become exercisable by virtue of (i) any person’s or group’s beneficial ownership, as of the Distribution Date, of 15% or more of the Class B Common Stock of the Company, unless such person or group acquires beneficial ownership of additional shares of the Company’s Class B Common Stock after June 18, 2018; (ii) the repurchase of the Company’s shares that causes a holder to become the beneficial owner of 15% or more of the Company’s Class B Common Stock, unless such holder acquires beneficial ownership of additional shares representing one percent or more of the Company’s Class B Common Stock; (iii) acquisitions by way of a pro rata stock dividend or a stock split; (iv) acquisitions solely as a result of any unilateral grant of any security by the Company or through the exercise of any options, warrants, rights or similar interests (including restricted stock) granted by the Company to its directors, officers and employees pursuant to any equity incentive or award plan; or (v) certain acquisitions determined by the Board of Directors to be inadvertent, provided, that following such acquisition, the acquirer promptly, but in any case within 10 business days, divests a sufficient number of shares so that such person would no longer otherwise qualify as an acquiring person.
Subsequent Event [Member]
Class of Stock [Line Items]
Remaining authorized amount under stock repurchase program	$ 429,000,000
Minimum [Member]
Class of Stock [Line Items]
Minimum percentage of beneficial ownership publicly announced to which trigger stockholder rights to become exercisable		15.00%
Transfer percentage		50.00%
Class A Common Stock [Member]
Class of Stock [Line Items]
Series Common stock, shares authorized		1,500,000,000	1,500,000,000
Series Common stock, par value		$ 0.01	$ 0.01
Common stock, shares outstanding		383,385,353	382,294,262	380,000,000	382,000,000
Aggregate amount of shares authorized to be repurchased						$ 500,000,000
Number of shares repurchased		0		3,000,000
Aggregate cost of shares repurchased				$ 0
Class A Common Stock [Member] | Subsequent Event [Member]
Class of Stock [Line Items]
Number of shares repurchased	5,200,000
Aggregate cost of shares repurchased	$ 71,000,000
Class B Common Stock [Member]
Class of Stock [Line Items]
Series Common stock, shares authorized		750,000,000	750,000,000
Series Common stock, par value		$ 0.01	$ 0.01
Common stock, shares outstanding		199,630,240	199,630,240	200,000,000	200,000,000
Number of shares repurchased				0
Aggregate cost of shares repurchased				$ 0
Series Common Stock [Member]
Class of Stock [Line Items]
Series Common stock, shares authorized		25,000,000
Series Common stock, par value		$ 0.01
Common stock, shares outstanding		0
Series Preferred Stock [Member]
Class of Stock [Line Items]
Preferred Stock, shares authorized		25,000,000
Preferred Stock, par value		$ 0.01
Preferred stock, share outstanding		0