Prepaid and Other Current Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Collateral posted with broker for derivative instruments (1)	$ 2,759	$ 215
Prepaid insurance	7,727	7,547
Derivative assets	5,164	4,296
Other	12,720	5,221
Total	$ 28,370	$ 17,279