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Revenue - Contract Assets and Liabilities (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2018 USD ($)
Costs in Excess of Billings
Beginning balance, January 1, 2018	$ 16,532
Costs in excess of billings to receivables	(14,950)
Costs in excess of billings recognized, net of reclassification to receivables	18,581
Ending balance, June 30, 2018	20,163
Billings in Excess of Cost
Beginning balance, January 1, 2018	(12,779)
Billings in excess of cost to revenue	9,044
Net billings in advance and cash payments not recognized as revenue	(11,792)
Ending balance, June 30, 2018	$ (15,527)

X

- Definition

Change in Contract with Customer, Asset [Roll Forward]

+ References

No definition available.

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Change in Contract with Customer, Liability [Roll Forward]

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- Definition

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X

- Definition

Contract With Customer, Liability, Increase From Billings And Cash Receipts

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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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 45
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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

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