Operating Leases (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Operating Leased Assets [Line Items]
Operating Leases, Rent Expense	$ 0	$ 900	$ 300	$ 4,500
Terminal Facilities
Operating Leased Assets [Line Items]
Operating Leases, Rent Expense	600	1,200	2,000	3,800
Terminal Facilities | Related Party [Member]
Operating Leased Assets [Line Items]
Operating Leases, Rent Expense	0	251	0	712
Related Party Transaction, Expenses from Transactions with Related Party	$ 0	$ 300	$ 0	$ 700