Commitments and Contingencies Commitment and Contingencies - Narrative (Details)		12 Months Ended					41 Months Ended
	Mar. 22, 2018 USD ($)	Dec. 31, 2019 USD ($) refinery claim	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2019 USD ($) refinery claim	Jun. 17, 2013 USD ($)
Long-term Purchase Commitment [Line Items]
Renewable identification numbers (RINs) benefit		$ 5,300,000
Number of owned and operated refineries | refinery		4					4
Site contingency reimbursement							$ 12,200,000
Bankruptcy claims number of claims to be settled | claim		2					2
Bankruptcy claims amount of claims to be settled		$ 22,400,000					$ 22,400,000
Settlement liabilities, current		500,000					500,000
Maximum bankruptcy claims remaining		$ 22,400,000					$ 22,400,000
Predecessor working ownership percentage		3.40%					3.40%
Allowed claims, settlement ratio			0.0544
One Major Customer | Customer Concentration Risk | Revenue from Contract with Customer Benchmark
Long-term Purchase Commitment [Line Items]
Concentration risk, percentage				10.00%
Wyoming Refinery One
Long-term Purchase Commitment [Line Items]
Accrual for environmental loss contingencies		$ 16,500,000					$ 16,500,000
Environmental costs recognized, period for recognition of one third costs		5 years
Environmental costs recognized, period for recognition		30 years
Wyoming Refinery Two | Waste Water Treatment System
Long-term Purchase Commitment [Line Items]
Accrual for environmental loss contingencies		$ 11,600,000					11,600,000
Wyoming Refinery
Long-term Purchase Commitment [Line Items]
Loss contingency, range of possible loss, portion not accrued		100,000					100,000
Maximum | Tesoro Corporation
Long-term Purchase Commitment [Line Items]
Contingent consideration, liability								$ 40,000,000
Tesoro Corporation
Long-term Purchase Commitment [Line Items]
Contingent consideration, liability								$ 20,000,000
Loss contingency, damages paid	$ 10,500,000				$ 16,800,000
Loss contingency, damages sought					$ 8,300,000	$ 4,300,000
Tesoro Corporation | Indemnification Agreement
Long-term Purchase Commitment [Line Items]
Guarantor obligations, deductible		1,000,000					1,000,000
Guarantor obligations, maximum exposure, undiscounted		$ 15,000,000					$ 15,000,000