Intangible Assets and Goodwill - Intangible Assets subject to Amortization (Details) - USD ($) $ in Millions	Mar. 31, 2021	Jun. 30, 2020
Finite-Lived Intangible Assets [Line Items]
Intangible assets subject to amortization, gross amount	$ 739.0	$ 811.0
Intangible assets subject to amortization, accumulated amortization	(526.6)	(531.4)
Intangible assets subject to amortization, net amount	212.4	279.6
Indefinite-lived Intangible Assets [Line Items]
Intangible assets not subject to amortization, gross amount	1,355.9	1,367.9
Intangible assets, net	1,568.3	1,647.5
Trademarks | National Media
Indefinite-lived Intangible Assets [Line Items]
Intangible assets not subject to amortization, gross amount	694.7	706.7
Internet domain names | National Media
Indefinite-lived Intangible Assets [Line Items]
Intangible assets not subject to amortization, gross amount	8.3	8.3
FCC licenses | Local Media
Indefinite-lived Intangible Assets [Line Items]
Intangible assets not subject to amortization, gross amount	652.9	652.9
Advertiser relationships | National Media
Finite-Lived Intangible Assets [Line Items]
Intangible assets subject to amortization, gross amount	211.0	211.0
Intangible assets subject to amortization, accumulated amortization	(211.0)	(170.0)
Intangible assets subject to amortization, net amount	0.0	41.0
Advertiser relationships | Local Media
Finite-Lived Intangible Assets [Line Items]
Intangible assets subject to amortization, gross amount	12.5	12.5
Intangible assets subject to amortization, accumulated amortization	(12.5)	(10.1)
Intangible assets subject to amortization, net amount	0.0	2.4
Publisher relationships | National Media
Finite-Lived Intangible Assets [Line Items]
Intangible assets subject to amortization, gross amount	132.8	132.8
Intangible assets subject to amortization, accumulated amortization	(58.0)	(43.9)
Intangible assets subject to amortization, net amount	74.8	88.9
Partner relationships | National Media
Finite-Lived Intangible Assets [Line Items]
Intangible assets subject to amortization, gross amount	98.2	98.2
Intangible assets subject to amortization, accumulated amortization	(50.8)	(38.7)
Intangible assets subject to amortization, net amount	47.4	59.5
Customer relationships | National Media
Finite-Lived Intangible Assets [Line Items]
Intangible assets subject to amortization, gross amount	8.0	71.3
Intangible assets subject to amortization, accumulated amortization	(3.5)	(65.6)
Intangible assets subject to amortization, net amount	4.5	5.7
Network affiliation agreements | Local Media
Finite-Lived Intangible Assets [Line Items]
Intangible assets subject to amortization, gross amount	229.3	229.3
Intangible assets subject to amortization, accumulated amortization	(166.2)	(161.5)
Intangible assets subject to amortization, net amount	63.1	67.8
Retransmission agreements | Local Media
Finite-Lived Intangible Assets [Line Items]
Intangible assets subject to amortization, gross amount	10.6	27.9
Intangible assets subject to amortization, accumulated amortization	(6.7)	(23.1)
Intangible assets subject to amortization, net amount	3.9	4.8
Other | National Media
Finite-Lived Intangible Assets [Line Items]
Intangible assets subject to amortization, gross amount	35.9	26.3
Intangible assets subject to amortization, accumulated amortization	(17.2)	(16.9)
Intangible assets subject to amortization, net amount	18.7	9.4
Other | Local Media
Finite-Lived Intangible Assets [Line Items]
Intangible assets subject to amortization, gross amount	0.7	1.7
Intangible assets subject to amortization, accumulated amortization	(0.7)	(1.6)
Intangible assets subject to amortization, net amount	$ 0.0	$ 0.1