Benefit Plans (Notes)

9 Months Ended

Sep. 30, 2014

Defined Benefit Pension Plans and Defined Benefit Postretirement Plans Disclosure [Abstract]

BENEFIT PLANS

BENEFIT PLANS

Tesoro sponsors four defined benefit pension plans, including one funded qualified employee retirement plan and three unfunded nonqualified executive plans. Although our funded employee retirement plan fully meets all funding requirements under applicable laws and regulations, we voluntarily contributed $60 million during the nine months ended September 30, 2014 to improve the funded status of the plan. Tesoro also provides other postretirement health care benefits to retirees who met certain service requirements and were participating in our group health insurance program at retirement.

The components of pension and other postretirement benefit expense (income) for the three and nine months ended September 30, 2014 and 2013 were (in millions):

	Pension Benefits
	Three Months Ended September 30,						Nine Months Ended September 30,
	2014			2013			2014			2013
Service cost	$	12		$	13		$	38		$	27
Interest cost	7			9			24			22
Expected return on plan assets	(6		)	(6		)	(21		)	(18		)
Amortization of prior service cost	—			1			1			1
Recognized net actuarial loss	3			3			10			16
Net Periodic Benefit Expense	$	16		$	20		$	52		$	48
	Other Postretirement Benefits
	Three Months Ended September 30,						Nine Months Ended September 30,
	2014			2013			2014			2013
Service cost	$	—		$	—		$	2		$	3
Interest cost	1			1			2			2
Amortization of prior service credit	(8		)	(8		)	(25		)	(27		)
Recognized net actuarial loss	1			1			4			6
Recognized curtailment gain	—			(17		)	—			(17		)
Net Periodic Benefit Income	$	(6	)	$	(23	)	$	(17	)	$	(33	)