Fair Value Measurements - Assets Acquired and Liabilities Assumed (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Jan. 11, 2019	Dec. 31, 2018	Mar. 23, 2018	Dec. 31, 2017
Goodwill	$ 127,997	$ 195,919		$ 153,397		$ 107,187
Washington Refinery Acquisition
Net working capital excluding operating leases			$ (35,854)
Property, plant, and equipment			412,766
Operating lease right-of-use assets			62,337
Goodwill			42,522
Current operating lease liabilities			(21,571)
Long-term operating lease liabilities			(40,766)
Deferred tax liability			(92,103)
Other non-current liabilities			(804)
Total			$ 326,527
Operating lease, discount rate			9.60%
Northwest Retail
Net working capital excluding operating leases					$ 3,822
Property, plant, and equipment					30,230
Goodwill					46,210
Long-term capital lease obligations					(5,244)
Other non-current liabilities					(487)
Total					$ 74,531