Indebtedness Indebtedness (Schedule of Maturities) (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Debt Instrument [Line Items]
Long-term Debt, Current Maturities	$ 441,061,000
2016	529,984,000
2017	554,840,000
2018	307,855,000
2019	881,374,000
Thereafter	1,735,633,000
Long-term Debt	4,450,747,000
Interest Paid, Net	229,000,000	254,200,000	246,100,000
Interest Paid, Capitalized	$ 17,600,000	$ 16,800,000	$ 9,400,000