Accounts Receivable - Third Parties Accounts Receivable—Third Parties (Schedule Of Accounts Receivable) (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Accounts Receivable, Net [Abstract]
Trade customers	$ 14,455	$ 17,325
Allowance for doubtful accounts	(728)	(921)
Trade Customer Receivable Net Current	13,727	16,404
Other	1,768	0
Accounts receivable, net—third parties	$ 15,495	$ 16,404