Assets and Liabilities Held for Sale (Details) - USD ($) $ in Thousands	Sep. 17, 2017	Sep. 30, 2017	Dec. 31, 2016	Sep. 30, 2016
Assets held for sale:
Cash and cash equivalents		$ 8,909		$ 0
Total current assets		78,223	$ 0
Liabilities held for sale:
Total current liabilities		19,990	$ 0
Bayou | Disposal Group, Held-for-sale, Not Discontinued Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Payment waiver	$ 1,500
Assets held for sale:
Cash and cash equivalents		8,910
Receivables, net		9,121
Costs and estimated earnings in excess of billings		831
Inventories		3,141
Prepaid expenses and other current assets		1,201
Total current assets		23,204
Property, plant & equipment, less accumulated depreciation		51,803
Identified intangible assets, less accumulated amortization		3,216
Total assets held for sale		78,223
Liabilities held for sale:
Accounts payable		2,196
Accrued expenses		3,373
Billings in excess of costs and estimated earnings		6,645
Total current liabilities		12,214
Long-term debt		7,689
Other non-current liabilities		87
Total liabilities held for sale		19,990
Non-controlling interests		$ 2,957