Discontinued Operations - Carrying Amount of Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Total current assets of discontinued operations	$ 17,456	$ 14,206
Total current liabilities of discontinued operations	17,107	14,541
Discontinued Operations | LOEN
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Trade accounts receivable, net	17,456	14,206
Total current assets of discontinued operations	17,456	14,206
Accounts payable	15,836	13,498
Accrued and other current liabilities	1,271	1,043
Total current liabilities of discontinued operations	$ 17,107	$ 14,541