Employee Benefit Plans (Tables)

12 Months Ended

Dec. 31, 2016

Compensation and Retirement Disclosure [Abstract]

Schedule of amounts recognized in balance sheet

Changes in benefit obligation and plan assets for the years ended December 31, 2016 and 2015, and amounts recognized in the Consolidated Balance Sheets at December 31, 2016 and 2015, were as follows:



	Pension Benefits						Other Postretirement Benefits
	2016			2015			2016			2015
	(In thousands)
Change in benefit obligation:
Benefit obligation at beginning of year	$	442,960		$	475,337		$	92,734		$	99,012
Service cost	—			86			1,647			1,816
Interest cost	17,218			17,141			3,688			3,607
Plan participants' contributions	—			—			1,405			1,408
Actuarial (gain) loss	1,882			(24,875		)	(3,872		)	(5,873		)
Benefits paid	(25,753		)	(24,729		)	(6,298		)	(7,236		)
Benefit obligation at end of year	436,307			442,960			89,304			92,734
Change in net plan assets:
Fair value of plan assets at beginning of year	332,667			354,363			82,593			87,586
Actual gain (loss) on plan assets	26,595			(10,879		)	4,184			258
Employer contribution	—			13,912			962			577
Plan participants' contributions	—			—			1,405			1,408
Benefits paid	(25,753		)	(24,729		)	(6,298		)	(7,236		)
Fair value of net plan assets at end of year	333,509			332,667			82,846			82,593
Funded status - under	$	(102,798	)	$	(110,293	)	$	(6,458	)	$	(10,141	)
Amounts recognized in the Consolidated Balance Sheets at December 31:
Other assets (noncurrent)	$	—		$	—		$	13,131		$	5,095
Other accrued liabilities (current)	—			—			(538		)	(421		)
Other liabilities (noncurrent)	(102,798		)	(110,293		)	(19,051		)	(14,815		)
Net amount recognized	$	(102,798	)	$	(110,293	)	$	(6,458	)	$	(10,141	)
Amounts recognized in accumulated other comprehensive (income) loss consist of:
Actuarial loss	$	198,668		$	208,671		$	17,470		$	22,484
Prior service cost (credit)	—			—			(13,003		)	(14,374		)
Total	$	198,668		$	208,671		$	4,467		$	8,110

The projected benefit obligation, accumulated benefit obligation and fair value of plan assets for the pension plans with accumulated benefit obligations in excess of plan assets

The pension plans all have accumulated benefit obligations in excess of plan assets. The projected benefit obligation, accumulated benefit obligation and fair value of plan assets for these plans at December 31 were as follows:



	2016		2015
	(In thousands)
Projected benefit obligation	$	436,307	$	442,960
Accumulated benefit obligation	$	436,307	$	442,960
Fair value of plan assets	$	333,509	$	332,667

Components of net periodic benefit cost

Components of net periodic benefit cost (credit) for the Company's pension and other postretirement benefit plans for the years ended December 31 were as follows:



	Pension Benefits									Other Postretirement Benefits
	2016			2015			2014			2016			2015			2014
	(In thousands)
Components of net periodic benefit cost (credit):
Service cost	$	—		$	86		$	129		$	1,647		$	1,816		$	1,518
Interest cost	17,218			17,141			17,682			3,688			3,607			3,521
Expected return on assets	(20,924		)	(22,254		)	(21,218		)	(4,533		)	(4,795		)	(4,617		)
Amortization of prior service cost (credit)	—			36			71			(1,371		)	(1,371		)	(1,393		)
Recognized net actuarial loss	6,215			7,016			4,869			1,491			1,960			649
Curtailment loss	—			258			—			—			—			—
Net periodic benefit cost (credit), including amount capitalized	2,509			2,283			1,533			922			1,217			(322		)
Less amount capitalized	381			316			388			(52		)	120			(21		)
Net periodic benefit cost (credit)	2,128			1,967			1,145			974			1,097			(301		)
Other changes in plan assets and benefit obligations recognized in accumulated other comprehensive (income) loss:
Net (gain) loss	(3,789		)	8,257			77,238			(3,523		)	(1,336		)	15,114
Amortization of actuarial loss	(6,215		)	(7,016		)	(4,869		)	(1,491		)	(1,960		)	(649		)
Amortization of prior service (cost) credit	—			(294		)	(71		)	1,371			1,371			1,393
Total recognized in accumulated other comprehensive (income) loss	(10,004		)	947			72,298			(3,643		)	(1,925		)	15,858
Total recognized in net periodic benefit cost (credit) and accumulated other comprehensive (income) loss	$	(7,876	)	$	2,914		$	73,443		$	(2,669	)	$	(828	)	$	15,557

Weighted average assumptions used to determine benefit obligations and net periodic benefit costs

Weighted average assumptions used to determine benefit obligations at December 31 were as follows:



	Pension Benefits				Other Postretirement Benefits
	2016		2015		2016		2015
Discount rate	3.83	%	4.00	%	3.86	%	4.06	%
Expected return on plan assets	6.75	%	6.75	%	5.75	%	5.75	%
Rate of compensation increase	N/A		N/A		3.00	%	3.00	%

Weighted average assumptions used to determine net periodic benefit cost for the years ended December 31 were as follows:



	Pension Benefits				Other Postretirement Benefits
	2016		2015		2016		2015
Discount rate	4.00	%	3.70	%	4.06	%	3.74	%
Expected return on plan assets	6.75	%	7.00	%	5.75	%	6.00	%
Rate of compensation increase	N/A		N/A		3.00	%	3.00	%

Health care rate assumptions for the Company's other postretirement benefit plans

Health care rate assumptions for the Company's other postretirement benefit plans as of December 31 were as follows:



				2016					2015
Health care trend rate assumed for next year	8.6	%	–	10.7	%	4.0	%	–	8.0	%
Health care cost trend rate - ultimate				4.5	%	5.0	%	–	6.0	%
Year in which ultimate trend rate achieved				2024					2021

Assumed health care cost trend rates

Assumed health care cost trend rates may have a significant effect on the amounts reported for the health care plans. A one percentage point change in the assumed health care cost trend rates would have had the following effects at December 31, 2016:



	1 Percentage Point Increase		1 Percentage Point Decrease
	(In thousands)
Effect on total of service and interest cost components	$	255	$	(210	)
Effect on postretirement benefit obligation	$	5,741	$	(4,834	)

The fair value of the pension and postretirement net plan assets by class

The fair value of the Company's pension plans' assets (excluding cash) by class were as follows:



	Fair Value Measurements at December 31, 2016, Using
	Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Balance at December 31, 2016
	(In thousands)
Assets:
Cash equivalents	$	—	$	6,347	$	—	$	6,347
Equity securities:
U.S. companies	11,348		—		—		11,348
International companies	1,584		—		—		1,584
Collective and mutual funds*	162,055		64,052		—		226,107
Corporate bonds	—		68,677		—		68,677
Municipal bonds	—		11,002		—		11,002
U.S. Government securities	4,352		2,044		—		6,396
Total assets measured at fair value	$	179,339	$	152,122	$	—	$	331,461


*	Collective and mutual funds invest approximately 29 percent in common stock of international companies, 21 percent in corporate bonds, 20 percent in common stock of large-cap U.S. companies, 8 percent in cash equivalents, 7 percent in U.S. Government securities and 15 percent in other investments.



	Fair Value Measurements at December 31, 2015, Using
	Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Balance at December 31, 2015
	(In thousands)
Assets:
Cash equivalents	$	—	$	8,379	$	—	$	8,379
Equity securities:
U.S. companies	15,135		—		—		15,135
International companies	2,332		—		—		2,332
Collective and mutual funds*	154,400		63,568		—		217,968
Corporate bonds	—		62,145		—		62,145
Municipal bonds	—		11,680		—		11,680
U.S. Government securities	5,288		6,823		—		12,111
Total assets measured at fair value	$	177,155	$	152,595	$	—	$	329,750


*	Collective and mutual funds invest approximately 29 percent in common stock of international companies, 19 percent in common stock of large-cap U.S. companies, 16 percent in corporate bonds, 16 percent in cash equivalents, 6 percent in common stock of mid-cap U.S. companies and 14 percent in other investments.

The fair value of the Company's other postretirement benefit plans' assets (excluding cash) by asset class were as follows:



	Fair Value Measurements at December 31, 2016, Using
	Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Balance at December 31, 2016
	(In thousands)
Assets:
Cash equivalents	$	—	$	250	$	—	$	250
Equity securities:
U.S. companies	2,328		—		—		2,328
International companies	5		—		—		5
Insurance contract*	—		80,263		—		80,263
Total assets measured at fair value	$	2,333	$	80,513	$	—	$	82,846


*	The insurance contract invests approximately 38 percent in corporate bonds, 25 percent in common stock of large-cap U.S. companies, 20 percent in U.S. Government securities, 9 percent in mortgage-backed securities and 8 percent in other investments.



	Fair Value Measurements at December 31, 2015, Using
	Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Balance at December 31, 2015
	(In thousands)
Assets:
Cash equivalents	$	—	$	3,261	$	—	$	3,261
Equity securities:
U.S. companies	2,274		—		—		2,274
International companies	9		—		—		9
Insurance contract*	—		77,044		—		77,044
Total assets measured at fair value	$	2,283	$	80,305	$	—	$	82,588


*	The insurance contract invests approximately 36 percent in corporate bonds, 22 percent in U.S. Government securities, 19 percent in common stock of large-cap U.S. companies, 10 percent in mortgage-backed securities and 13 percent in other investments.

Benefit payments expected to be paid

The following benefit payments, which reflect future service, as appropriate, and expected Medicare Part D subsidies are as follows:



Years	Pension Benefits		Other Postretirement Benefits		Expected Medicare Part D Subsidy
			(In thousands)
2017	$	24,798	$	5,410	$	168
2018	25,054		5,573		165
2019	25,271		5,603		160
2020	25,616		5,500		154
2021	25,987		5,511		146
2022 - 2026	132,224		27,956		568

Multiemployer plans



	EIN/Pension Plan Number	Pension Protection Act Zone Status		FIP/RP Status Pending/Implemented	Contributions						Surcharge Imposed	Expiration Date of Collective Bargaining Agreement
Pension Fund		2016	2015		2016		2015		2014
					(In thousands)
Alaska Laborers-Employers Retirement Fund	91-6028298-001	Yellow as of 6/30/2016	Yellow as of 6/30/2015	Implemented	$	766	$	917	$	666	No	12/31/2016
Edison Pension Plan	93-6061681-001	Green as of 12/31/2016	Green as of 12/31/2015	No	6,242		5,517		9,061		No	12/31/2017
IBEW Local No. 82 Pension Plan	31-6127268-001	Green as of 6/30/2016	Red as of 6/30/2015	Implemented	2,560		2,252		1,392		No	12/1/2019
IBEW Local No. 357 Pension Plan A	88-6023284-001	Green	Green	No	3,016		1,896		3,575		No	5/31/2018
IBEW Local 648 Pension Plan	31-6134845-001	Red as of 2/29/2016	Red as of 2/28/2015	Implemented	773		745		1,110		No	9/2/2018
Idaho Plumbers and Pipefitters Pension Plan	82-6010346-001	Green as of 5/31/2016	Green as of 5/31/2015	No	1,221		1,169		1,125		No	9/30/2019
Local Union 212 IBEW Pension Trust Fund	31-6127280-001	Yellow as of 4/30/2016	Yellow as of 4/30/2015	Implemented	1,146		937		568		No	6/2/2019
National Automatic Sprinkler Industry Pension Fund	52-6054620-001	Red as of 12/31/2016	Red as of 12/31/2015	Implemented	775		677		608		No	7/31/2018- 3/31/2021
National Electrical Benefit Fund	53-0181657-001	Green	Green	No	6,366		5,271		6,476		No	1/1/2017- 5/31/2020
Operating Engineers Local 800 & WY Contractors Association, Inc. Pension Plan for Wyoming**	83-6011320-001	Red as of 12/31/2016	Red as of 12/31/2015	Implemented	—		—		68		No	10/31/2005*
Sheet Metal Workers' Pension Plan of Southern CA, AZ and NV	95-6052257-001	Red as of 12/31/2016	Red as of 12/31/2015	Implemented	1,087		714		676		No	6/30/2017
Southwest Marine Pension Trust	95-6123404-001	Red	Red	Implemented	50		26		31		No	1/31/2019
Other funds					20,525		18,991		17,461
Total contributions					$	44,527	$	39,112	$	42,817


*	Plan includes collective bargaining agreements which have expired. The agreements contain provisions that automatically renew the existing contracts in lieu of a new negotiated collective bargaining agreement.


**	The Company withdrew from the plan as of October 26, 2014, as discussed later.

The Company was listed in the plans' Forms 5500 as providing more than 5 percent of the total contributions for the following plans and plan years:



Pension Fund	Year Contributions to Plan Exceeded More Than 5 Percent of Total Contributions (as of December 31 of the Plan's Year-End)
Edison Pension Plan	2015 and 2014
IBEW Local No. 82 Pension Plan	2015 and 2014
Local Union No. 124 IBEW Pension Trust Fund	2015 and 2014
Local Union 212 IBEW Pension Trust Fund	2015 and 2014
IBEW Local Union No. 357 Pension Plan A	2015 and 2014
IBEW Local 573 Pension Plan	2014
IBEW Local 648 Pension Plan	2015 and 2014
Idaho Plumbers and Pipefitters Pension Plan	2015 and 2014
Minnesota Teamsters Construction Division Pension Fund	2015 and 2014
Operating Engineers Local 800 & WY Contractors Association, Inc. Pension Plan for Wyoming*	2014
Pension and Retirement Plan of Plumbers and Pipefitters Union Local No. 525	2015 and 2014


*	The Company withdrew from the plan as of October 26, 2014, as discussed later.