v3.8.0.1

EMPLOYEE BENEFIT PLANS (Tables)

12 Months Ended

Dec. 31, 2017

Retirement Benefits [Abstract]

Disclosures for our Pension Plans and other postretirement benefit plans

The changes in the benefit obligation, the changes in fair value of plan assets, the funded status and the amounts recognized in the consolidated balance sheets for our Pension Plans and other postretirement benefit plans as of and for the years ended December 31, 2017 and 2016 were as follows:

	Pension Plans								Other Postretirement Benefit Plans
	2017				2016				2017				2016
	(Thousands of Dollars)
Change in benefit obligation:
Benefit obligation, January 1	$	127,402			$	109,202			$	11,061			$	10,042
Service cost	8,955				7,703				456				419
Interest cost	4,507				4,023				430				401
Benefits paid	(5,941		)		(2,554		)		(342		)		(422		)
Participant contributions	—				—				215				253
Actuarial loss	14,894				9,028				590				368
Benefit obligation, December 31	$	149,817			$	127,402			$	12,410			$	11,061
Change in plan assets:
Plan assets at fair value, January 1	$	107,644			$	87,706			$	—			$	—
Actual return on plan assets	17,070				6,891				—				—
Employer contributions	11,105				15,601				127				169
Benefits paid	(5,941		)		(2,554		)		(342		)		(422		)
Participant contributions	—				—				215				253
Plan assets at fair value, December 31	$	129,878			$	107,644			$	—			$	—
Reconciliation of funded status:
Fair value of plan assets at December 31	$	129,878			$	107,644			$	—			$	—
Less: Benefit obligation at December 31	149,817				127,402				12,410				11,061
Funded status at December 31	$	(19,939	)		$	(19,758	)		$	(12,410	)		$	(11,061	)
Amounts recognized in the consolidated balance sheets (a):
Accrued liabilities	$	(210	)		$	(162	)		$	(376	)		$	(321	)
Other long-term liabilities	(19,729		)		(19,596		)		(12,034		)		(10,740		)
Net pension liability	$	(19,939	)		$	(19,758	)		$	(12,410	)		$	(11,061	)

(a) For the Pension Plan, since assets exceed the present value of expected benefit payments for the next 12 months, all of the liability is noncurrent. For the Excess Pension Plan and the other postretirement benefit plans, since there are no assets, the current liability is the present value of expected benefit payments for the next 12 months; the remainder is noncurrent.

The components of net periodic benefit cost (income)

The components of net periodic benefit cost (income) related to our Pension Plans and other postretirement benefit plans were as follows:

	Pension Plans												Other Postretirement Benefit Plans
	Year Ended December 31,												Year Ended December 31,
	2017				2016				2015				2017				2016				2015
	(Thousands of Dollars)
Service cost	$	8,955			$	7,703			$	7,676			$	456			$	419			$	470
Interest cost	4,507				4,023				4,389				430				401				448
Expected return on plan assets	(6,411		)		(5,407		)		(5,018		)		—				—				—
Amortization of prior service credit	(2,059		)		(2,063		)		(2,063		)		(1,145		)		(1,145		)		(1,145		)
Amortization of net actuarial loss	1,484				1,091				1,845				191				181				269
Net periodic benefit cost (income)	$	6,476			$	5,347			$	6,829			$	(68	)		$	(144	)		$	42

Adjustments recognized in other comprehensive (loss) income

Adjustments to other comprehensive (loss) income related to our Pension Plans and other postretirement benefit plans were as follows:

	Pension Plans												Other Postretirement Benefit Plans
	Year Ended December 31,												Year Ended December 31,
	2017				2016				2015				2017				2016				2015
	(Thousands of Dollars)
Net unrecognized (loss) gain arising during the year:
Net actuarial (loss) gain	$	(4,235	)		$	(7,544	)		$	1,000			$	(590	)		$	(368	)		$	1,056
Net (gain) loss reclassified into income:
Amortization of prior service credit	(2,059		)		(2,063		)		(2,063		)		(1,145		)		(1,145		)		(1,145		)
Amortization of net actuarial loss	1,484				1,091				1,845				191				181				269
Net gain reclassified into income	(575		)		(972		)		(218		)		(954		)		(964		)		(876		)
Income tax benefit (expense)	162				57				(362		)		22				3				(382		)
Total changes to other comprehensive (loss) income	$	(4,648	)		$	(8,459	)		$	420			$	(1,522	)		$	(1,329	)		$	(202	)

The amounts recorded as a component of accumulated other comprehensive (loss) income

The amounts recorded as a component of “Accumulated other comprehensive loss” on the consolidated balance sheets related to our Pension Plans and other postretirement benefit plans were as follows:

	Pension Plans								Other Postretirement Benefit Plans
	December 31,								December 31,
	2017				2016				2017				2016
	(Thousands of Dollars)
Unrecognized actuarial loss	$	(31,178	)		$	(28,427	)		$	(4,154	)		$	(3,755	)
Prior service credit	16,604				18,663				9,464				10,609
Deferred tax asset	219				57				25				3
Accumulated other comprehensive (loss) income, net of tax	$	(14,355	)		$	(9,707	)		$	5,335			$	6,857

Schedule of pre-tax amounts in accumulated other comprehensive loss to be recognized over next fiscal year

The following pre-tax amounts in accumulated other comprehensive loss as of December 31, 2017 are expected to be recognized as components of net periodic benefit cost (income) in 2018:

	Pension Plans				Other Postretirement Benefit Plans
	(Thousands of Dollars)
Actuarial loss	$	2,174			$	214
Prior service credit	$	(2,057	)		$	(1,145	)

Schedule of fair value of plan assets

The major classes of plan assets measured at fair value for the Pension Plan were as follows:

	December 31, 2017
	Level 1				Level 2				Level 3				Total
	(Thousands of Dollars)
Cash equivalent securities	$	381			$	—			$	—			$	381
Equity securities:
U.S. large cap equity fund (a)	—				75,353				—				75,353
International stock index fund (b)	14,480				—				—				14,480
Fixed income securities:
Bond market index fund (c)	39,664				—				—				39,664
Total	$	54,525			$	75,353			$	—			$	129,878

	December 31, 2016
	Level 1				Level 2				Level 3				Total
	(Thousands of Dollars)
Cash equivalent securities	$	738			$	—			$	—			$	738
Equity securities:
U.S. large cap equity fund (a)	—				64,813				—				64,813
International stock index fund (b)	10,459				—				—				10,459
Fixed income securities:
Bond market index fund (c)	31,634				—				—				31,634
Total	$	42,831			$	64,813			$	—			$	107,644

(a) This fund is a low-cost equity index fund not actively managed that tracks the S&P 500. Fair values were estimated using pricing models, quoted prices of securities with similar characteristics or discounted cash flows.

(b) This fund tracks the performance of the Total International Composite Index.

(c) This fund tracks the performance of the Barclays Capital U.S. Aggregate Bond Index.

Schedule of expected benefit payments

The following benefit payments, which reflect expected future service, as appropriate, are expected to be paid for the years ending December 31:

	Pension Plans				Other Postretirement Benefit Plans
	(Thousands of Dollars)
2018	$	8,823			$	376
2019	$	9,699			$	416
2020	$	10,432			$	434
2021	$	11,050			$	464
2022	$	11,650			$	497
Years 2023-2027	$	64,799			$	3,090

Assumptions used to determine the benefit obligations

The weighted-average assumptions used to determine the benefit obligations were as follows:

	Pension Plans						Other Postretirement Benefit Plans
	December 31,						December 31,
	2017			2016			2017			2016
Discount rate	3.72	%		4.33	%		3.82	%		4.49	%
Rate of compensation increase	3.51	%		3.51	%		n/a			n/a

Assumptions used to determine the net periodic benefit cost (income)

The weighted-average assumptions used to determine the net periodic benefit cost (income) were as follows:

	Pension Plans									Other Postretirement Benefit Plans
	Year Ended December 31,									Year Ended December 31,
	2017			2016			2015			2017			2016			2015
Discount rate	4.33	%		4.61	%		4.22	%		4.49	%		4.75	%		4.34	%
Expected long-term rate of return on plan assets	6.00	%		6.25	%		6.50	%		n/a			n/a			n/a
Rate of compensation increase	3.51	%		3.51	%		3.51	%		n/a			n/a			n/a

Schedule of assumed health care cost trend rates

The assumed health care cost trend rates were as follows:

	December 31,
	2017			2016
Health care cost trend rate assumed for next year	6.84	%		6.84	%
Rate to which the cost trend rate was assumed to decrease (the ultimate trend rate)	5.00	%		5.00	%
Year that the rate reaches the ultimate trend rate	2028			2028

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