Summary of Significant Accounting Policies (Additional Information) (Details) $ / shares in Units, $ in Thousands		3 Months Ended	12 Months Ended
	Jan. 01, 2018 USD ($)	Mar. 31, 2018 USD ($)	Jun. 30, 2018 USD ($) segment station $ / shares shares	Jun. 30, 2017 USD ($) $ / shares shares	Jun. 30, 2016 USD ($)	Jan. 31, 2018 shares	Jan. 30, 2018 $ / shares	Jul. 01, 2017 USD ($)	Jun. 30, 2015 USD ($)
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Number of reportable segments | segment			2
Number of owned television stations | station			17
Other revenue, typical period of adjustment to estimated sales			3 months
Cash and cash equivalents			$ 437,600	$ 22,300	$ 25,000				$ 22,800
LIFO inventory income recognized		$ 1,300	(1,300)	(1,700)	(700)
Advertising expenses			$ 122,800	$ 63,900	$ 72,600
Likelihood of recognized income tax positions are sustained, minimum percentage			50.00%
Preferred stock issued (in shares) | shares			700,000	700,000
Preferred stock par value (in usd per share) | $ / shares			$ 1.00	$ 1.00
Cumulative effect adjustment for adoption of Accounting Standards Update 2016-09			$ 500
Deferred income taxes			437,000	$ 384,700
Reclassification adjustment for adoption of Accounting Standards Update 2018-02	$ 4,000		0
Minimum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Stop loss contract amount to cap self-insured medical claims			350
Maximum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Stop loss contract amount to cap self-insured medical claims			$ 500
Series A Preferred Stock
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Preferred stock issued (in shares) | shares						650,000
Preferred stock par value (in usd per share) | $ / shares			$ 1.00				$ 1,000
Domestic
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cash and cash equivalents			$ 411,100
Foreign
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cash and cash equivalents			26,500
Money market funds | Domestic
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cash and cash equivalents			370,200
Additional Paid-in Capital
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative effect adjustment for adoption of Accounting Standards Update 2016-09			1,100
Retained Earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative effect adjustment for adoption of Accounting Standards Update 2016-09			(600)
Reclassification adjustment for adoption of Accounting Standards Update 2018-02			4,000
Accounting Standards Update 2016-09, Forfeiture Rate Component
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Deferred income taxes								$ (500)
Accounting Standards Update 2016-09, Forfeiture Rate Component | Additional Paid-in Capital
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative effect adjustment for adoption of Accounting Standards Update 2016-09								1,100
Accounting Standards Update 2016-09, Forfeiture Rate Component | Retained Earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative effect adjustment for adoption of Accounting Standards Update 2016-09								$ 600
Quoted Prices (Level 1)
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cash and cash equivalents			$ 373,100