Revenue from Contracts with Customers - Performance Obligations Unsatisfied at End of Period (Details) $ in Thousands	Mar. 31, 2019 USD ($)
Revenue from Contract with Customer [Abstract]
Performance obligation unsatisfied or partially unsatisfied	$ 1,639
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2019-04-01
Revenue from Contract with Customer [Abstract]
Performance obligation unsatisfied or partially unsatisfied	$ 671
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Estimated remaining performance period	9 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-01-01
Revenue from Contract with Customer [Abstract]
Performance obligation unsatisfied or partially unsatisfied	$ 369
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Estimated remaining performance period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01
Revenue from Contract with Customer [Abstract]
Performance obligation unsatisfied or partially unsatisfied	$ 303
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Estimated remaining performance period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01
Revenue from Contract with Customer [Abstract]
Performance obligation unsatisfied or partially unsatisfied	$ 153
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Estimated remaining performance period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
Revenue from Contract with Customer [Abstract]
Performance obligation unsatisfied or partially unsatisfied	$ 143
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Estimated remaining performance period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01
Revenue from Contract with Customer [Abstract]
Performance obligation unsatisfied or partially unsatisfied	$ 0
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Estimated remaining performance period	1 year

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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=109196051&loc=SL49130556-203045

+ Details

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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

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=109196051&loc=SL49130556-203045

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