Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2019

Property Plant And Equipment Estimated Useful Life

We compute depreciation of property, plant, and equipment using the straight-line method, based on the estimated useful life of each asset as follows:



Assets		Lives in Years
Refining		5 to 47
Logistics		3 to 30
Retail		3 to 30
Corporate		3 to 7
Software		3 to 5

Summary of Depreciation Expense

The following table summarizes depreciation and finance lease amortization expense excluded from each line item in our consolidated statements of operations (in thousands):



	Year Ended December 31,
	2019		2018		2017
Cost of revenues	$	16,882	$	6,722	$	6,029
Operating expense	55,181		28,037		22,861
General and administrative expense	3,145		4,233		2,929