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Revenue - Contract Assets and Liabilities (Details) $ in Thousands | 3 Months Ended
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Mar. 31, 2018 USD ($)
Costs in Excess of Billings |
Beginning balance, January 1, 2018 | $ 16,532
Costs in excess of billings to receivables | (11,647)
Costs in excess of billings recognized, net of reclassification to receivables | 17,329
Ending balance, March 31, 2018 | 22,214
Billings in Excess of Cost |
Beginning balance, January 1, 2018 | (12,779)
Billings in excess of cost to revenue | 8,340
Net billings in advance and cash payments not recognized as revenue | (7,133)
Ending balance, March 31, 2018 | $ (11,572)

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- Definition Change in Contract with Customer, Liability [Roll Forward] + References No definition available. + Details
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- Definition Contract With Customer, Asset, New Contract Additions + References No definition available. + Details
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- Definition Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 45 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=82913815&loc=SL49130533-203044 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 270 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=84173487&loc=SL51747714-108306 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=82913815&loc=SL49130531-203044 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 8 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=82913847&loc=SL49130549-203045 + Details
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