Fair Value Disclosure of Financial Instruments (Assets and Liabilities Measured at Fair Value on Recurring Basis) (Details) (Fair Value, Measurements, Recurring, USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Derivative financial instruments, Asset	$ 444	$ 288
Derivative financial instruments, Liability	20,015	21,423
Quoted Prices in Active Markets for Identical Assets and Liabilities (Level 1)
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Derivative financial instruments, Asset	0	0
Derivative financial instruments, Liability	0	0
Significant Other Observable Inputs (Level 2)
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Derivative financial instruments, Asset	444	288
Derivative financial instruments, Liability	20,015	21,423
Significant Unobservable Inputs (Level 3)
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Derivative financial instruments, Asset	0	0
Derivative financial instruments, Liability	$ 0	$ 0