Revenue - Performance Obligations (Details) $ in Thousands	12 Months Ended
Dec. 31, 2019 USD ($)
Revenue
Future revenue related to current unsatisfied performance obligations	$ 35,914
Original expected durations	true
Revenue, Practical Expedient, Incremental Cost of Obtaining Contract [true/false]	true
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-01-01
Revenue
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	12 months
Future revenue related to current unsatisfied performance obligations	$ 11,295
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01
Revenue
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	12 months
Future revenue related to current unsatisfied performance obligations	$ 7,682
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01
Revenue
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	12 months
Future revenue related to current unsatisfied performance obligations	$ 5,951
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
Revenue
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	12 months
Future revenue related to current unsatisfied performance obligations	$ 10,986

Indicates (true false) whether practical expedient was elected to recognize incremental cost of obtaining contract as expense when incurred if amortization period would have been one year or less.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 340
-SubTopic 40
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=68051541&loc=SL51790836-203054

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 22
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130569-203045

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- Definition

Indicates (true false) whether optional exemption was applied not to disclose amount of transaction price allocated to and explanation of expected timing of revenue recognition for remaining performance obligation, when contract has expected duration of one year or less or right to consideration corresponds directly to performance completed.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130558-203045

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- Definition

Amount of transaction price allocated to performance obligation that has not been recognized as revenue.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130556-203045

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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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- Definition

Period in which remaining performance obligation is expected to be recognized as revenue, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130556-203045

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