Selected Balance Sheet Information (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Schedule of Equity Method Investments [Line Items]
Accrued Liabilities, Current	$ 477,284	$ 490,260
Deferred income taxes	57,337	49,809
Equity Method Investments	$ 49,144	$ 32,624