Fair Value Measurements (Narrative) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2013	Dec. 31, 2014
Fair Value Measurements [Abstract]
Interest rate swap agreement for notional amount	$ 300,000,000
Fair value of debt	1,508,000,000		$ 1,624,300,000
Impairment of long lived assets	343,300,000
Reduction in value of goodwill	1,326,701,000	$ 91,016,000
Impairment of Long-Lived Assets Held-for-use	343,300,000
Impairment of Intangible Assets, Finite-lived	$ 68,900,000