Revenue From Contracts With Customers - Contract Balances Outstanding (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Current deferred revenue
Current deferred revenue
Balance as of December 31, 2017	$ 5,380	$ 20,784
Increases due to billings	7,961	15,548
Revenue recognized	(4,678)	(30,803)
Foreign currency impact	71	(149)
Balance as of December 31, 2018	11,776	5,380
Long-Term deferred revenue
Increases due to billings	7,961	15,548
Revenue recognized	(4,678)	(30,803)
Foreign currency impact	71	(149)
Contract with Customer, Asset, Reclassified to Receivable	3,042
Long-Term deferred revenue
Disaggregation of Revenue [Line Items]
Contract with Customer, Liability, Cumulative Catch-up Adjustment to Revenue, Modification of Contract	(694)
Current deferred revenue
Increases due to billings	0	8,241
Revenue recognized	0	0
Foreign currency impact	(122)	(525)
Long-Term deferred revenue
Balance as of December 31, 2017	7,716	0
Increases due to billings	0	8,241
Revenue recognized	0	0
Foreign currency impact	(122)	(525)
Balance as of December 31, 2018	3,858	$ 7,716
Contract with Customer, Asset, Reclassified to Receivable	$ (3,042)

Contract with Customer, Liability, Current [Roll Forward]

No definition available.

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- Definition

Contract with Customer, Liability, Foreign Currency Impact

+ References

No definition available.

+ Details

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- Definition

Contract with Customer, Liability, Noncurrent [Roll Forward]

+ References

No definition available.

+ Details

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- Definition

Amount of decrease in right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time from transfer to receivable due to right to consideration becoming unconditional.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130551-203045

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- Definition

Amount of increase (decrease) in revenue recognized for cumulative catch-up adjustment from contract modification which (increases) decreases obligation to transfer good or service to customer for which consideration from customer has been received or is due.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130551-203045

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- Definition

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

+ References

Reference 1: 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

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 8
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- Definition

Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

+ References

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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.

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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.

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