Contract Receivables (Details) $ in Thousands	12 Months Ended
Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2018 USD ($) Customer	Dec. 31, 2017 USD ($) Customer
Contract Receivables [Abstract]
Maximum term of contract receivables	12 months
Components of contract receivables [Abstract]
Billed receivables			$ 15,998	$ 8,154
Unbilled receivables			5,506	5,980
Allowance for doubtful accounts	$ (137)	$ (137)	(427)	(137)
Total contract receivables, net			$ 21,077	$ 13,997
Subsequent Billing	4,100
Allowance for Doubtful Accounts Receivable [Roll Forward]
Beginning balance	137	17
Current year provision	294	118
Current year write-offs	0	0
Currency adjustment	(4)	2
Ending balance	$ 427	$ 137
Contract Receivables [Member]
Concentration Risk [Line Items]
Number of customers accounted for receivables \| Customer			1	1
Concentration risk, percentage	16.80%	26.70%

Describes the maximum period under which the entity considered its contract receivables to be collected.

No definition available.

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- Definition

Currency adj

+ References

No definition available.

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- Definition

Number of accounted customers for consolidated contract receivables.

+ References

No definition available.

+ Details

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- Definition

Subsequent billing

+ References

No definition available.

+ Details

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- Definition

Amount billed to customers under long-term contracts or programs but not paid. Excludes amounts due that have been withheld because of retainage provisions in a contract.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.3(c))
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-Section 50
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-URI http://asc.fasb.org/extlink&oid=68065756&loc=d3e49354-109356

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Balance Type:	debit
Period Type:	instant

- Definition

For an unclassified balance sheet, a valuation allowance for receivables due a company that are expected to be uncollectible.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Balance Type:	credit
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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

+ Details

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- Definition

Amount of direct write-downs of accounts receivable charged against the allowance.

+ References

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- Definition

Amounts due for billed services rendered or to be rendered, actions taken or to be taken, or a promise to refrain from taking certain actions in accordance with the terms of a legally binding agreement between the Company and, at a minimum, one other party. An example would be amounts billed to customers under contracts or programs but not paid as of the balance sheet date.

+ References

+ Details

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Balance Type:	debit
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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- References

No definition available.

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- Definition

Amount of expense related to write-down of receivables to the amount expected to be collected. Includes, but is not limited to, accounts receivable and notes receivable.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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- References

No definition available.

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- Definition

Unbilled amounts due for services rendered or to be rendered, actions taken or to be taken, or a promise to refrain from taking certain actions in accordance with the terms of a legally binding agreement between the entity and, at a minimum, one other party. An example would be amounts associated with contracts or programs where the recognized revenue for performance thereunder exceeds the amounts billed under the terms thereof as of the date of the balance sheet.

+ References

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