v3.20.4

EMPLOYEE BENEFIT PLANS (Tables)

12 Months Ended

Dec. 31, 2020

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, 2020 and 2019 were as follows:

			Pension Plans												Other Postretirement Benefit Plans
			2020						2019						2020						2019
			(Thousands of Dollars)
Change in benefit obligation:
Benefit obligation, January 1			$	167,257					$	141,833					$	13,196					$	10,908
Service cost			9,174						9,549						529						431
Interest cost			4,693						5,480						399						453
Benefits paid			(9,520)						(7,109)						(281)						(217)
Participant contributions			—						—						44						62
Actuarial loss			15,081						17,504						793						1,559
Benefit obligation, December 31			$	186,685					$	167,257					$	14,680					$	13,196
Change in plan assets:
Plan assets at fair value, January 1			$	159,036					$	126,949					$	—					$	—
Actual return on plan assets			21,758						28,064						—						—
Employer contributions			11,453						11,132						237						155
Benefits paid			(9,520)						(7,109)						(281)						(217)
Participant contributions			—						—						44						62
Plan assets at fair value, December 31			$	182,727					$	159,036					$	—					$	—
Reconciliation of funded status:
Fair value of plan assets at December 31			$	182,727					$	159,036					$	—					$	—
Less: Benefit obligation at December 31			186,685						167,257						14,680						13,196
Funded status at December 31			$	(3,958)					$	(8,221)					$	(14,680)					$	(13,196)
Amounts recognized in the consolidated balance sheets (a):
Accrued liabilities			$	(382)					$	(303)					$	(352)					$	(368)
Other long-term liabilities			(3,576)						(7,918)						(14,328)						(12,828)
Net pension liability			$	(3,958)					$	(8,221)					$	(14,680)					$	(13,196)
Accumulated benefit obligation			$	181,263					$	164,183					$	14,680					$	13,196

(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,
			2020						2019						2018						2020						2019						2018
			(Thousands of Dollars)
Service cost			$	9,174					$	9,549					$	9,621					$	529					$	431					$	504
Interest cost			4,693						5,480						4,824						399						453						429
Expected return on plan assets			(8,972)						(8,015)						(7,417)						—						—						—
Amortization of prior service credit			(2,057)						(2,057)						(2,057)						(1,145)						(1,145)						(1,145)
Amortization of net actuarial loss			1,845						846						2,174						137						42						214
Excess Pension Plan settlement			136						—						—						—						—						—
Net periodic benefit cost (income)			$	4,819					$	5,803					$	7,145					$	(80)					$	(219)					$	2

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,
			2020						2019						2018						2020						2019						2018
			(Thousands of Dollars)
Net unrecognized (loss) gain arising during the year:
Net actuarial (loss) gain			$	(2,159)					$	2,545					$	1,049					$	(793)					$	(1,559)					$	2,267
Net (gain) loss reclassified into income:
Amortization of prior service credit			(2,057)						(2,057)						(2,057)						(1,145)						(1,145)						(1,145)
Amortization of net actuarial loss			1,845						846						2,174						137						42						214
Net (gain) loss reclassified into income			(212)						(1,211)						117						(1,008)						(1,103)						(931)
Reclassification of stranded tax effects			—						—						(74)						—						—						—
Income tax benefit (expense)			28						14						(69)						—						—						(25)
Total changes to other comprehensive (loss) income			$	(2,343)					$	1,348					$	1,023					$	(1,801)					$	(2,662)					$	1,311

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,
			2020						2019						2020						2019
			(Thousands of Dollars)
Unrecognized actuarial loss			$	(24,878)					$	(24,564)					$	(3,846)					$	(3,190)
Prior service credit			10,433						12,490						6,029						7,174
Deferred tax asset			118						90						—						—
Accumulated other comprehensive (loss) income, net of tax			$	(14,327)					$	(11,984)					$	2,183					$	3,984

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, 2020
			Level 1						Level 2						Level 3						Total
			(Thousands of Dollars)
Cash equivalent securities			$	2,125					$	—					$	—					$	2,125
Equity securities:
U.S. large cap equity fund (a)			—						104,857						—						104,857
International stock index fund (b)			20,732						—						—						20,732
Fixed income securities:
Bond market index fund (c)			55,013						—						—						55,013
Total			$	77,870					$	104,857					$	—					$	182,727

			December 31, 2019
			Level 1						Level 2						Level 3						Total
			(Thousands of Dollars)
Cash equivalent securities			$	160					$	—					$	—					$	160
Equity securities:
U.S. large cap equity fund (a)			—						92,737						—						92,737
International stock index fund (b)			17,473						—						—						17,473
Fixed income securities:
Bond market index fund (c)			48,666						—						—						48,666
Total			$	66,299					$	92,737					$	—					$	159,036

(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)
2021			$	9,771					$	352
2022			$	10,030					$	397
2023			$	10,329					$	451
2024			$	10,846					$	483
2025			$	11,558					$	529
2026-2030			$	61,321					$	3,355

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,
			2020						2019						2020						2019
Discount rate			2.84		%				3.34		%				2.83		%				3.43		%
Rate of compensation increase			3.51		%				3.51		%				n/a						n/a
Cash balance interest crediting rate			2.00		%				2.00		%				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,
			2020						2019						2018						2020						2019						2018
Discount rate			3.34		%				4.40		%				3.72		%				3.43		%				4.53		%				3.82		%
Expected long-term rate of return on plan assets			6.50		%				6.50		%				6.50		%				n/a						n/a						n/a
Rate of compensation increase			3.51		%				3.51		%				3.51		%				n/a						n/a						n/a
Cash balance interest crediting rate			2.00		%				2.90		%				2.00		%				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,
			2020						2019
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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