Assets and Liabilities Held for Sale (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017	Sep. 30, 2017
Assets held for sale:
Cash and cash equivalents	$ 0	$ 1,000	$ 8,909
Total current assets	10,173	70,314
Liabilities held for sale:
Total current liabilities	6,423	20,900
Disposal Group, Held-for-sale, Not Discontinued Operations
Assets held for sale:
Cash and cash equivalents	0
Receivables, net	2,003
Retainage	16
Contract assets	2,185
Inventories	1,804
Prepaid expenses and other current assets	250
Total current assets	6,258
Property, plant & equipment, less accumulated depreciation	3,915
Identified intangible assets, less accumulated amortization	0
Total assets held for sale	10,173
Liabilities held for sale:
Accounts payable	985
Accrued expenses	5,399
Contract liabilities	39
Total current liabilities	6,423
Long-term debt	0
Other non-current liabilities	0
Total liabilities held for sale	6,423
Bayou | Disposal Group, Held-for-sale, Not Discontinued Operations
Assets held for sale:
Cash and cash equivalents		989
Receivables, net		6,368
Retainage		0
Contract assets		1,299
Inventories		3,727
Prepaid expenses and other current assets		827
Total current assets		13,210
Property, plant & equipment, less accumulated depreciation		53,887
Identified intangible assets, less accumulated amortization		3,217
Total assets held for sale		70,314
Liabilities held for sale:
Accounts payable		5,763
Accrued expenses		1,805
Contract liabilities		5,478
Total current liabilities		13,046
Long-term debt		7,757
Other non-current liabilities		97
Total liabilities held for sale		$ 20,900
Australia | Disposal Group, Held-for-sale, Not Discontinued Operations
Assets held for sale:
Cash and cash equivalents	0
Receivables, net	2,003
Retainage	16
Contract assets	2,185
Inventories	1,769
Prepaid expenses and other current assets	250
Total current assets	6,223
Property, plant & equipment, less accumulated depreciation	2,315
Identified intangible assets, less accumulated amortization	0
Total assets held for sale	8,538
Liabilities held for sale:
Accounts payable	985
Accrued expenses	5,399
Contract liabilities	39
Total current liabilities	6,423
Long-term debt	0
Other non-current liabilities	0
Total liabilities held for sale	6,423
Denmark | Disposal Group, Held-for-sale, Not Discontinued Operations
Assets held for sale:
Cash and cash equivalents	0
Receivables, net	0
Retainage	0
Contract assets	0
Inventories	35
Prepaid expenses and other current assets	0
Total current assets	35
Property, plant & equipment, less accumulated depreciation	1,600
Identified intangible assets, less accumulated amortization	0
Total assets held for sale	1,635
Liabilities held for sale:
Accounts payable	0
Accrued expenses	0
Contract liabilities	0
Total current liabilities	0
Long-term debt	0
Other non-current liabilities	0
Total liabilities held for sale	$ 0