Financial Instruments Financial Instruments - Schedule of Interest Rate Derivatives (Details) (Interest Rate Contract [Member], Not Designated as Hedging Instrument [Member], USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Noncurrent Derivative Assets [Member]
Derivatives, Fair Value [Line Items]
Interest Rate Derivative Assets, at Fair Value	$ 71,170	$ 98,123
Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Interest Rate Derivative Liabilities, at Fair Value	$ 19,544	$ 13,484