Benefit Plans (Notes)

6 Months Ended

Jun. 30, 2012

Compensation and Retirement Disclosure [Abstract]

BENEFIT PLANS

BENEFIT PLANS

Tesoro sponsors the following four defined benefit pension plans: the funded qualified employee retirement plan, the unfunded nonqualified executive security plan, the unfunded nonqualified restoration retirement plan and the unfunded nonqualified supplemental executive retirement plan. Although our funded employee retirement plan fully meets all funding requirements under applicable laws and regulations, we voluntarily contributed $24 million during the six months ended June 30, 2012 to improve the funded status of the plan.

The components of pension benefit expense and other postretirement benefit expense (income) included in the condensed statements of consolidated operations for the three and six months ended June 30, 2012 and 2011, were (in millions):

	Pension Benefits
	Three Months Ended						Six Months Ended
	June 30,						June 30,
	2012			2011			2012			2011
Service cost	$	7		$	7		$	14		$	14
Interest cost	8			8			15			15
Expected return on plan assets	(6		)	(5		)	(12		)	(10		)
Recognized net actuarial loss	5			5			11			10
Recognized curtailment loss	—			1			—			3
Net Periodic Benefit Expense	$	14		$	16		$	28		$	32
	Other Postretirement Benefits
	Three Months Ended						Six Months Ended
	June 30,						June 30,
	2012			2011			2012			2011
Service cost	$	1		$	2		$	2		$	3
Interest cost	1			1			2			2
Amortization of prior service credit	(10		)	(10		)	(19		)	(19		)
Recognized net actuarial loss	3			3			6			6
Net Periodic Benefit Income	$	(5	)	$	(4	)	$	(9	)	$	(8	)