Debt, Revolver and Senior Notes (Details) (USD $)			12 Months Ended					0 Months Ended	12 Months Ended	0 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2012 Revolving Credit Facility		Dec. 31, 2012 Revolving Credit Facility Revolver Amendment	Feb. 21, 2013 Revolving Credit Facility Revolver Amendment	Jan. 04, 2013 Revolving Credit Facility Revolver Amendment	Sep. 14, 2012 Senior Notes	Dec. 31, 2012 Senior Notes	Sep. 14, 2012 Senior Notes Prior to October 1, 2015	Sep. 14, 2012 Senior Notes On or after October 1, 2016	Sep. 14, 2012 Senior Notes On or after October 1, 2017
Line of Credit Facility
Available borrowing capacity			$ 300,000,000			$ 500,000,000	$ 500,000,000
Collateral, Revolving Credit Facility			The Revolving Credit Facility is non-recourse to Tesoro, except for TLGP and is guaranteed by all of our subsidiaries and secured by substantially all of our assets.
Borrowing capacity, description			Borrowings are available under the Revolving Credit Facility up to the total loan availability of the facility.
Amount outstanding	0	50,000,000	0
Letters of credit, amount outstanding			300,000
Unused credit availability			299,700,000
Remaining percentage of eligible borrowing base			99.00%
30 day Eurodollar (LIBOR) Rate			0.21%	[1]
Eurodollar Margin			3.25%	[1]
Base Rate			3.25%	[1]
Base Rate Margin			2.25%	[1]
Commitment Fee (unused portion)			0.50%	[1]
Maximum borrowing capacity							650,000,000
Minimum decrease in margins							0.50%
Maximum decrease in margins							1.00%
Maturity date					Dec. 31, 2017
Senior Notes
Aggregate principal amount								$ 350,000,000
Interest rate								5.875%
Maturity date									Oct. 01, 2020
Redemption price, percentage										105.875%	2.938%	1.469%
Percentage redemption with equity proceeds										35.00%
Collateral, Senior Notes								The Senior Notes are unsecured and guaranteed by all of our domestic subsidiaries, except Tesoro Logistics Finance Corp., the co-issuer of the Senior Notes.

[1] We have the option to elect if the borrowings will bear interest at either a base rate plus the base rate margin, or a Eurodollar rate, for the applicable period, plus the Eurodollar margin at the time of the borrowing. The applicable margin varies based upon a certain leverage ratio, as defined by the Revolving Credit Facility. We also incur commitment fees for the unused portion of the Revolving Credit Facility at an annual rate. Letters of credit outstanding under the Revolving Credit Facility incur fees at the Eurodollar margin rate.