Revenues from Contracts with Customers - Performance Obligations (Details) $ in Thousands	Sep. 30, 2020 USD ($)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-10-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation, expected timing of satisfaction, period	3 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation, expected timing of satisfaction, period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation, expected timing of satisfaction, period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation, expected timing of satisfaction, period
Third-Party Customer
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
HEP contractual minimum revenues, performance obligations expected to be satisfied	$ 59,629
Third-Party Customer | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-10-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
HEP contractual minimum revenues, performance obligations expected to be satisfied	$ 6,441
Remaining performance obligation, expected timing of satisfaction, period	3 months
Third-Party Customer | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
HEP contractual minimum revenues, performance obligations expected to be satisfied	$ 21,942
Remaining performance obligation, expected timing of satisfaction, period	1 year
Third-Party Customer | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
HEP contractual minimum revenues, performance obligations expected to be satisfied	$ 10,954
Remaining performance obligation, expected timing of satisfaction, period	1 year
Third-Party Customer | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
HEP contractual minimum revenues, performance obligations expected to be satisfied	$ 20,292
Remaining performance obligation, expected timing of satisfaction, period