Details Of Certain Accounts (Accrued Liabilities) (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Accrued payroll and related benefits	$ 19,490	$ 61,246
Current asset retirement obligations	554	575
Unearned revenue	6,700	11,461
Accrued interest	4,882	4,221
Derivative liability (Note 14)	19,390	13,222
Taxes payable excluding income tax payable	6,583	6,236
Other	9,189	7,962
Total accrued liabilities	$ 66,788	$ 104,923