Annual report pursuant to Section 13 and 15(d)

Fair Value Measurements (Fair Value of Assets and Liabilities Measured on Recurring Basis) (Details)

v3.6.0.2
Fair Value Measurements (Fair Value of Assets and Liabilities Measured on Recurring Basis) (Details) - USD ($)
$ in Thousands
Dec. 31, 2016
Dec. 31, 2015
Derivative Assets    
Derivative Asset $ 103 $ 19,943
Derivative Liabilities    
Derivative Liabilities (18,296)  
Total net assets (18,193) 19,943
Level 2 [Member]    
Derivative Assets    
Derivative Asset 103 19,943
Derivative Liabilities    
Derivative Liabilities (18,296)  
Total net assets $ (18,193) $ 19,943