Intangible Assets (Intangible Assets) (Details) (USD $)
12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Indefinite-Lived Intangible Assets (Excluding Goodwill) $ 18,000,000  
Gross Carrying Value 1,091,405,000 1,205,450,000
Accumulated Amortization (287,281,000) (243,081,000)
Net Carrying Value 804,124,000 962,369,000
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life 15 years  
Licenses [Member]    
Gross Carrying Value 1,091,405,000 1,205,450,000
Accumulated Amortization (287,281,000) (243,081,000)
Net Carrying Value $ 804,124,000 $ 962,369,000