Fair Value Measurements (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Assets (Liabilities)
Total	$ 10,284	$ 49,846
Fair value on a recurring basis
Assets (Liabilities)
Derivative Asset	800	284
Derivative Liability	9,484	49,562
Total	10,284	49,846
Fair value on a recurring basis | Level 1
Assets (Liabilities)
Derivative Asset	0	0
Derivative Liability	0	0
Total	0	0
Fair value on a recurring basis | Level 2
Assets (Liabilities)
Derivative Asset	800	284
Derivative Liability	9,484	49,562
Total	10,284	49,846
Fair value on a recurring basis | Level 3
Assets (Liabilities)
Derivative Asset	0	0
Derivative Liability	0	0
Total	$ 0	$ 0