Leases and Other Commitments (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Operating Leased Assets [Line Items]
Future minimum sublease payments due	$ 93.0
Rent expense for operating leases	86.9	$ 102.6	$ 105.5
Sublease rental income	14.3	$ 6.7	$ 5.4
Secondarily liable leases	51.3
Television Broadcasting [Member]
Operating Leased Assets [Line Items]
Long-term programming purchase commitment	$ 16.4