Long-Term Debt Long Term Debt (Schedule of Equity Units) (Details) - USD ($)							1 Months Ended		12 Months Ended
		Aug. 15, 2016		Jul. 01, 2016	Apr. 01, 2016	Jul. 01, 2014	Jul. 31, 2016	Apr. 30, 2016	Dec. 31, 2016	Dec. 31, 2015	Mar. 31, 2016
Capital Unit [Line Items]
Stock Purchase Contract Liability	[1]								$ 212,000,000	$ 115,000,000
Total payments									$ 94,000,000	$ 101,000,000
Capital Unit, Class A
Capital Unit [Line Items]
Units Issued		28,000,000	[2]			20,000,000
Total Net Proceeds		$ 1,374,800,000	[2]			$ 982,000,000
Stock Purchase Contract Annual Rate (percentage)		4.75%	[2]			4.875%
Stock Purchase Contract Liability	[1]	$ 190,600,000	[2]			$ 142,800,000
Capital Unit, Class A | Remarketable Subordinated Notes
Capital Unit [Line Items]
Units Issued				8,500,000.0	8,500,000.0		8,500,000.0	8,500,000.0
Total Long-term Debt		$ 1,400,000,000.0	[2]			$ 1,000,000,000					$ 550,000,000
RSN Annual Interest Rate		2.00%	[2],[3]			1.50%					1.07%
Capital Unit, Class A | Remarketable Subordinated Notes, 2016 Series A-1, due August 15, 2021
Capital Unit [Line Items]
Total Long-term Debt		$ 700,000,000
Capital Unit, Class A | Remarketable Subordinated Notes, 2016 Series A-2, due August 15, 2024
Capital Unit [Line Items]
Total Long-term Debt		$ 700,000,000

[1] Payments of $94 million and $101 million were made in 2016 and 2015, respectively, including payments for the remarketed 2013 Series A and B notes. The stock purchase contract liability was $212 million and $115 million at December 31, 2016 and 2015, respectively.

[2] The maturity dates of the $700 million Series A-1 RSNs and $700 million Series A-2 RSNs are August 15, 2021 and August 15, 2024, respectively.

[3] Annual interest rate applies to each of the Series A-1 RSNs and Series A-2 RSNs.