Leases (Schedule of lease assets and liabilities) (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Leases [Abstract]
Operating right of use asset	$ 8,302	$ 0
Finance right of use assets	18,416
Total right of use assets	26,718
Current operating lease liability	4,519	0
Current finance lease liability	4,081
Operating lease liability	3,556	$ 0
Finance lease liability	5,319
Total lease liability	$ 17,475