Intangible Assets and Goodwill (Intangible Assets) (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended			12 Months Ended
	May 31, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2017	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2017
Finite and Indefinite-lived Intangible Assets by Major Class [Line Items]
Intangible assets subject to amortization, gross amount		$ 798.6	$ 805.7		$ 798.6	$ 805.7
Intangible assets subject to amortization, accumulated amortization		(392.5)	(248.8)		(392.5)	(248.8)
Intangible assets subject to amortization, net amount		406.1	556.9		406.1	556.9
Intangible assets not subject to amortization		1,407.5	1,449.3		1,407.5	1,449.3
Intangible assets, net		1,813.6	2,006.2		1,813.6	2,006.2
Amortization expense					155.1	74.8	$ 19.1
Expected future amortization expense, 2020		140.8			140.8
Expected future amortization expense, 2021		84.2			84.2
Expected future amortization expense, 2022		41.4			41.4
Expected future amortization expense, 2023		39.6			39.6
Expected future amortization expense, 2024		32.5			32.5
Trademarks
Finite and Indefinite-lived Intangible Assets by Major Class [Line Items]
Impairment of indefinite lived intangible assets	$ 41.8	41.8	2.9	$ 19.8		22.7
National Media | Trademarks
Finite and Indefinite-lived Intangible Assets by Major Class [Line Items]
Intangible assets not subject to amortization		724.5	766.3		724.5	766.3
National Media | Trademarks | Impairment of goodwill and other long-lived assets
Finite and Indefinite-lived Intangible Assets by Major Class [Line Items]
Impairment of indefinite lived intangible assets							$ 5.3
National Media | Internet domain names
Finite and Indefinite-lived Intangible Assets by Major Class [Line Items]
Intangible assets not subject to amortization		7.8	7.8		7.8	7.8
National Media | Advertiser relationships
Finite and Indefinite-lived Intangible Assets by Major Class [Line Items]
Intangible assets subject to amortization, gross amount		213.3	212.3		213.3	212.3
Intangible assets subject to amortization, accumulated amortization		(102.0)	(41.1)		(102.0)	(41.1)
Intangible assets subject to amortization, net amount		111.3	171.2		111.3	171.2
National Media | Publisher relationships
Finite and Indefinite-lived Intangible Assets by Major Class [Line Items]
Intangible assets subject to amortization, gross amount		125.0	125.0		125.0	125.0
Intangible assets subject to amortization, accumulated amortization		(25.4)	(7.4)		(25.4)	(7.4)
Intangible assets subject to amortization, net amount		99.6	117.6		99.6	117.6
National Media | Partner relationships
Finite and Indefinite-lived Intangible Assets by Major Class [Line Items]
Intangible assets subject to amortization, gross amount		98.2	95.0		98.2	95.0
Intangible assets subject to amortization, accumulated amortization		(22.7)	(6.6)		(22.7)	(6.6)
Intangible assets subject to amortization, net amount		75.5	88.4		75.5	88.4
National Media | Customer lists
Finite and Indefinite-lived Intangible Assets by Major Class [Line Items]
Intangible assets subject to amortization, gross amount		67.5	67.5		67.5	67.5
Intangible assets subject to amortization, accumulated amortization		(46.3)	(14.0)		(46.3)	(14.0)
Intangible assets subject to amortization, net amount		21.2	53.5		21.2	53.5
National Media | Other
Finite and Indefinite-lived Intangible Assets by Major Class [Line Items]
Intangible assets subject to amortization, gross amount		23.2	22.0		23.2	22.0
Intangible assets subject to amortization, accumulated amortization		(14.9)	(11.9)		(14.9)	(11.9)
Intangible assets subject to amortization, net amount		8.3	10.1		8.3	10.1
Local Media | FCC licenses
Finite and Indefinite-lived Intangible Assets by Major Class [Line Items]
Intangible assets not subject to amortization		675.2	675.2		675.2	675.2
Local Media | Advertiser relationships
Finite and Indefinite-lived Intangible Assets by Major Class [Line Items]
Intangible assets subject to amortization, gross amount		12.5	25.0		12.5	25.0
Intangible assets subject to amortization, accumulated amortization		(5.8)	(3.5)		(5.8)	(3.5)
Intangible assets subject to amortization, net amount		6.7	21.5		6.7	21.5
Local Media | Other
Finite and Indefinite-lived Intangible Assets by Major Class [Line Items]
Intangible assets subject to amortization, gross amount		1.7	1.7		1.7	1.7
Intangible assets subject to amortization, accumulated amortization		(1.2)	(0.8)		(1.2)	(0.8)
Intangible assets subject to amortization, net amount		0.5	0.9		0.5	0.9
Local Media | Network
Finite and Indefinite-lived Intangible Assets by Major Class [Line Items]
Intangible assets subject to amortization, gross amount		229.3	229.3		229.3	229.3
Intangible assets subject to amortization, accumulated amortization		(155.1)	(148.6)		(155.1)	(148.6)
Intangible assets subject to amortization, net amount		74.2	80.7		74.2	80.7
Local Media | Retransmission agreements
Finite and Indefinite-lived Intangible Assets by Major Class [Line Items]
Intangible assets subject to amortization, gross amount		27.9	27.9		27.9	27.9
Intangible assets subject to amortization, accumulated amortization		(19.1)	(14.9)		(19.1)	(14.9)
Intangible assets subject to amortization, net amount		$ 8.8	$ 13.0		$ 8.8	$ 13.0