Revenue Recognition - Disaggregation of Revenue (Details) - USD ($) $ in Millions	3 Months Ended			6 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Dec. 31, 2019	Dec. 31, 2018
Disaggregation of Revenue [Line Items]
Total revenues	$ 810.5	$ 878.4		$ 1,535.7	$ 1,652.8
Total advertising related
Disaggregation of Revenue [Line Items]
Total revenues	427.3	492.3		806.9	917.8
Print
Disaggregation of Revenue [Line Items]
Total revenues	149.4	167.4		309.8	352.6
Non-political spot
Disaggregation of Revenue [Line Items]
Total revenues	89.5	87.6		166.3	162.5
Political spot
Disaggregation of Revenue [Line Items]
Total revenues	4.4	65.8		7.0	101.9
Digital
Disaggregation of Revenue [Line Items]
Total revenues	137.1	126.9		232.9	215.7
Third party sales
Disaggregation of Revenue [Line Items]
Total revenues	46.9	44.6		90.9	85.1
Total consumer related
Disaggregation of Revenue [Line Items]
Total revenues	348.9	368.2	$ 327.8	672.0	696.0
Subscription
Disaggregation of Revenue [Line Items]
Total revenues	159.8	192.0		310.3	352.7
Retransmission
Disaggregation of Revenue [Line Items]
Total revenues	85.1	74.1		164.7	147.4
Newsstand
Disaggregation of Revenue [Line Items]
Total revenues	37.7	43.5		80.3	82.6
Affinity marketing
Disaggregation of Revenue [Line Items]
Total revenues	20.0	18.3		33.9	37.2
Licensing
Disaggregation of Revenue [Line Items]
Total revenues	24.4	23.7		44.4	48.5
Digital and other consumer driven
Disaggregation of Revenue [Line Items]
Total revenues	21.9	16.6		38.4	27.6
Total other
Disaggregation of Revenue [Line Items]
Total revenues	34.3	17.9		56.8	39.0
Projects based
Disaggregation of Revenue [Line Items]
Total revenues	15.1	13.5		29.5	22.9
Other
Disaggregation of Revenue [Line Items]
Total revenues	19.2	4.4		27.3	16.1
Operating segments
Disaggregation of Revenue [Line Items]
Total revenues	811.2	878.6		1,536.9	1,653.6
Operating segments | National media
Disaggregation of Revenue [Line Items]
Total revenues	597.2	616.2		1,130.1	1,176.8
Operating segments | National media | Total advertising related
Disaggregation of Revenue [Line Items]
Total revenues	302.0	306.4		573.0	593.6
Operating segments | National media | Print
Disaggregation of Revenue [Line Items]
Total revenues	149.4	167.4		309.8	352.6
Operating segments | National media | Non-political spot
Disaggregation of Revenue [Line Items]
Total revenues	0.0	0.0		0.0	0.0
Operating segments | National media | Political spot
Disaggregation of Revenue [Line Items]
Total revenues	0.0	0.0		0.0	0.0
Operating segments | National media | Digital
Disaggregation of Revenue [Line Items]
Total revenues	132.2	122.9		223.8	207.8
Operating segments | National media | Third party sales
Disaggregation of Revenue [Line Items]
Total revenues	20.4	16.1		39.4	33.2
Operating segments | National media | Total consumer related
Disaggregation of Revenue [Line Items]
Total revenues	263.8	294.1		507.3	548.6
Operating segments | National media | Subscription
Disaggregation of Revenue [Line Items]
Total revenues	159.8	192.0		310.3	352.7
Operating segments | National media | Retransmission
Disaggregation of Revenue [Line Items]
Total revenues	0.0	0.0		0.0	0.0
Operating segments | National media | Newsstand
Disaggregation of Revenue [Line Items]
Total revenues	37.7	43.5		80.3	82.6
Operating segments | National media | Affinity marketing
Disaggregation of Revenue [Line Items]
Total revenues	20.0	18.3		33.9	37.2
Operating segments | National media | Licensing
Disaggregation of Revenue [Line Items]
Total revenues	24.4	23.7		44.4	48.5
Operating segments | National media | Digital and other consumer driven
Disaggregation of Revenue [Line Items]
Total revenues	21.9	16.6		38.4	27.6
Operating segments | National media | Total other
Disaggregation of Revenue [Line Items]
Total revenues	31.4	15.7		49.8	34.6
Operating segments | National media | Projects based
Disaggregation of Revenue [Line Items]
Total revenues	15.1	13.5		29.5	22.9
Operating segments | National media | Other
Disaggregation of Revenue [Line Items]
Total revenues	16.3	2.2		20.3	11.7
Operating segments | Local media
Disaggregation of Revenue [Line Items]
Total revenues	214.0	262.4		406.8	476.8
Operating segments | Local media | Total advertising related
Disaggregation of Revenue [Line Items]
Total revenues	126.0	186.1		235.1	325.0
Operating segments | Local media | Print
Disaggregation of Revenue [Line Items]
Total revenues	0.0	0.0		0.0	0.0
Operating segments | Local media | Non-political spot
Disaggregation of Revenue [Line Items]
Total revenues	89.5	87.6		166.3	162.5
Operating segments | Local media | Political spot
Disaggregation of Revenue [Line Items]
Total revenues	4.4	65.8		7.0	101.9
Operating segments | Local media | Digital
Disaggregation of Revenue [Line Items]
Total revenues	4.9	4.0		9.1	7.9
Operating segments | Local media | Third party sales
Disaggregation of Revenue [Line Items]
Total revenues	27.2	28.7		52.7	52.7
Operating segments | Local media | Total consumer related
Disaggregation of Revenue [Line Items]
Total revenues	85.1	74.1		164.7	147.4
Operating segments | Local media | Subscription
Disaggregation of Revenue [Line Items]
Total revenues	0.0	0.0		0.0	0.0
Operating segments | Local media | Retransmission
Disaggregation of Revenue [Line Items]
Total revenues	85.1	74.1		164.7	147.4
Operating segments | Local media | Newsstand
Disaggregation of Revenue [Line Items]
Total revenues	0.0	0.0		0.0	0.0
Operating segments | Local media | Affinity marketing
Disaggregation of Revenue [Line Items]
Total revenues	0.0	0.0		0.0	0.0
Operating segments | Local media | Licensing
Disaggregation of Revenue [Line Items]
Total revenues	0.0	0.0		0.0	0.0
Operating segments | Local media | Digital and other consumer driven
Disaggregation of Revenue [Line Items]
Total revenues	0.0	0.0		0.0	0.0
Operating segments | Local media | Total other
Disaggregation of Revenue [Line Items]
Total revenues	2.9	2.2		7.0	4.4
Operating segments | Local media | Projects based
Disaggregation of Revenue [Line Items]
Total revenues	0.0	0.0		0.0	0.0
Operating segments | Local media | Other
Disaggregation of Revenue [Line Items]
Total revenues	2.9	2.2		7.0	4.4
Intersegment eliminations
Disaggregation of Revenue [Line Items]
Total revenues	(0.7)	(0.2)		(1.2)	(0.8)
Intersegment eliminations | Total advertising related
Disaggregation of Revenue [Line Items]
Total revenues	(0.7)	(0.2)		(1.2)	(0.8)
Intersegment eliminations | Print
Disaggregation of Revenue [Line Items]
Total revenues	0.0	0.0		0.0	0.0
Intersegment eliminations | Non-political spot
Disaggregation of Revenue [Line Items]
Total revenues	0.0	0.0		0.0	0.0
Intersegment eliminations | Political spot
Disaggregation of Revenue [Line Items]
Total revenues	0.0	0.0		0.0	0.0
Intersegment eliminations | Digital
Disaggregation of Revenue [Line Items]
Total revenues	0.0	0.0		0.0	0.0
Intersegment eliminations | Third party sales
Disaggregation of Revenue [Line Items]
Total revenues	(0.7)	(0.2)		(1.2)	(0.8)
Intersegment eliminations | Total consumer related
Disaggregation of Revenue [Line Items]
Total revenues	0.0	0.0		0.0	0.0
Intersegment eliminations | Subscription
Disaggregation of Revenue [Line Items]
Total revenues	0.0	0.0		0.0	0.0
Intersegment eliminations | Retransmission
Disaggregation of Revenue [Line Items]
Total revenues	0.0	0.0		0.0	0.0
Intersegment eliminations | Newsstand
Disaggregation of Revenue [Line Items]
Total revenues	0.0	0.0		0.0	0.0
Intersegment eliminations | Affinity marketing
Disaggregation of Revenue [Line Items]
Total revenues	0.0	0.0		0.0	0.0
Intersegment eliminations | Licensing
Disaggregation of Revenue [Line Items]
Total revenues	0.0	0.0		0.0	0.0
Intersegment eliminations | Digital and other consumer driven
Disaggregation of Revenue [Line Items]
Total revenues	0.0	0.0		0.0	0.0
Intersegment eliminations | Total other
Disaggregation of Revenue [Line Items]
Total revenues	0.0	0.0		0.0	0.0
Intersegment eliminations | Projects based
Disaggregation of Revenue [Line Items]
Total revenues	0.0	0.0		0.0	0.0
Intersegment eliminations | Other
Disaggregation of Revenue [Line Items]
Total revenues	$ 0.0	$ 0.0		$ 0.0	$ 0.0