Revenue Contract Liabilities (Details) $ in Thousands	9 Months Ended
Sep. 30, 2018 USD ($)
Movement in Deferred Revenue [Roll Forward]
Contract with Customer, Liability	$ 7,066
Contract with Customer, Liability	7,874
Equipment revenue [Member]
Movement in Deferred Revenue [Roll Forward]
Deferred Revenue, Additions	4,086
Increase (Decrease) in Deferred Revenue	(3,136)
Software revenue [Member]
Movement in Deferred Revenue [Roll Forward]
Deferred Revenue, Additions	5,507
Increase (Decrease) in Deferred Revenue	$ (5,649)

Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82913815&loc=SL49130532-203044

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130549-203045

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

Amount of deferred revenue recognized for transactions arising during the current reporting period. Deferred revenue is a liability as of the balance sheet date related to a revenue producing activity for which revenue has not yet been recognized. Generally, an Entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

+ References

No definition available.

+ Details

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- Definition

The increase (decrease) during the reporting period, excluding the portion taken into income, in the liability reflecting revenue yet to be earned for which cash or other forms of consideration was received or recorded as a receivable.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

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Balance Type:	debit
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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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- Details

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- Details

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