Equity Incentive Plan - Phantom unit award (Details) - Phantom unit awards $ in Millions	3 Months Ended
Mar. 31, 2020 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation not yet recognized	$ 0.5
Recognition period for costs not yet recognized	3 years
Vesting Alternative One, One Year from Grant Date
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting rate (as a percent)	33.00%
Vesting Alternative One, Two Years from Grant Date
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting rate (as a percent)	33.00%
Vesting Alternative One, Three Years from Grant Date
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting rate (as a percent)	34.00%

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

+ References

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- Definition

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+ References

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- Definition

Percentage of vesting of award under share-based payment arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Section 50
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