Employee Benefits

3 Months Ended

Mar. 31, 2016

Compensation and Retirement Disclosure [Abstract]

Employee Benefits

Employee Benefits

The Company has a noncontributory defined benefit pension plan covering a majority of its employees and postretirement medical and life insurance plans providing coverage to less than half of its employees. Employees hired or rehired after June 30, 2010, are not eligible for the noncontributory defined benefit pension plan and employees hired or rehired after December 31, 1996, are not eligible for the postretirement medical plan and are not eligible to receive basic life insurance once they retire.

Questar is subject to and complies with minimum-required and maximum-allowed annual contribution levels for its qualified pension plan, as determined by the Employee Retirement Income Security Act and the Internal Revenue Code. The 2016 estimated net cost for the qualified pension plan is $8.2 million.

The Company also has a nonqualified pension plan that covers a group of management employees in addition to the noncontributory qualified pension plan. The nonqualified pension plan provides for defined benefit payments upon retirement of the management employee, above the benefit limit defined by the Internal Revenue Service (IRS) for the qualified plan. The nonqualified pension plan is unfunded; benefits are paid from the Company's general funds. The 2016 estimated net cost for the nonqualified pension plan is $3.0 million.

Components of the qualified and nonqualified net periodic pension cost are listed in the table below:

	3 Months Ended						12 Months Ended
	March 31,						March 31,
	2016			2015			2016			2015
	(in millions)
Service cost	$	3.0		$	3.4		$	13.4		$	12.2
Interest cost	8.2			8.1			32.8			33.1
Expected return on plan assets	(12.2		)	(11.6		)	(48.3		)	(44.6		)
Prior service cost	—			—			0.1			0.5
Recognized net actuarial loss	3.8			5.7			20.0			17.2
Pension settlement costs	—			—			16.7			—
Net pension cost	$	2.8		$	5.6		$	34.7		$	18.4

The Company currently estimates a $2.1 million net cost for postretirement benefits other than pensions in 2016, before accretion of a regulatory liability. Net periodic postretirement benefit cost components are listed in the table below:

	3 Months Ended						12 Months Ended
	March 31,						March 31,
	2016			2015			2016			2015
	(in millions)
Service cost	$	0.1		$	0.2		$	0.5		$	0.6
Interest cost	0.9			0.9			3.5			3.7
Expected return on plan assets	(0.7		)	(0.8		)	(3.1		)	(3.0		)
Recognized net actuarial loss	0.2			0.3			1.1			0.7
Accretion of regulatory liability	0.2			0.2			1.0			0.8
Net postretirement benefit cost	$	0.7		$	0.8		$	3.0		$	2.8