Receivables - Narrative (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Other receivables	$ 7,229	$ 7,225
Foreign
Accounts, Notes, Loans and Financing Receivable [Line Items]
Other receivables	$ 5,900	$ 6,300