Retirement Benefit Plans (Tables)

12 Months Ended

Dec. 31, 2017



	2017		2016		2017		2016
(in thousands)	Pension Benefits				Other Post- Retirement Benefits
Change in benefit obligation
Benefit obligation:
at beginning of year	$	479,281	$	462,819	$	22,481	$	22,281
Service cost		15,381		14,098		129		170
Interest cost		16,514		16,907		668		773
Plan participants' contributions		—		—		636		1,269
Plan amendments		(17,315)		—		—		(1,224)
Net actuarial loss		39,419		16,944		993		1,844
Benefits paid		(19,436)		(31,487)		(1,871)		(2,632)
Benefit obligation, end of year		513,844		479,281		23,036		22,481
Change in plan assets
Fair value of plan assets:
at beginning of year		515,555		491,550		—		—
Actual return on plan assets		68,307		40,375		—		—
Employer contributions		1,132		16,123		1,235		1,363
Plan participants' contributions		—		—		636		1,269
Benefit payments		(19,436)		(31,487)		(1,871)		(2,632)
Expenses		(1,193)		(1,006)		—		—
Fair value of plan assets, end of year		564,365		515,555		—		—
Funded status at end of year - net asset (liability)	$	50,521	$	36,274	$	(23,036)	$	(22,481)
Amounts recognized in accumulated other comprehensive loss
Unrecognized loss:
at beginning of year	$	115,910	$	109,565	$	(2,078)	$	(2,553)
Net actuarial loss (gain)		(12,932)		6,345		1,346		475
Unrecognized loss at end of year	$	102,978	$	115,910	$	(732)	$	(2,078)

Projected benefit obligation	$	513,844	$	479,281
Accumulated benefit obligation		489,075		443,261
Fair value of plan assets		564,365		515,555



	Years Ended December 31,
	2017		2016		2015		2017		2016		2015
($ in thousands)	Pension Benefits						Other Post-Retirement Benefits
Net periodic benefit cost
Service cost	$	15,381	$	14,098	$	13,511	$	129	$	170	$	117
Interest cost		16,514		16,907		18,635		668		773		891
Expected return on plan assets		(37,632)		(34,554)		(32,833)		—		—		—
Amortization of net loss/ prior service cost		5,554		5,783		3,169		(353)		145		6
Net periodic benefit cost		(183)		2,234		2,482		444		1,088		1,014
Other changes in plan assets and benefit obligations recognized in other comprehensive income, before taxes
Net (loss) gain recognized during the year		(5,554)		(5,783)		(3,169)		353		(145)		(6)
Net actuarial loss (gain)		(7,378)		12,128		39,876		993		620		(5,905)
Total recognized in other comprehensive income		(12,932)		6,345		36,707		1,346		475		(5,911)
Total recognized in net periodic benefit cost and other comprehensive income	$	(13,115)	$	8,579	$	39,189	$	1,790	$	1,563	$	(4,897)

Discount rate for benefit obligations		3.57%		4.10%		4.40%		3.52%		3.95%		4.32%
Discount rate for net periodic benefit cost		4.10%		4.40%		4.11%		3.95%		4.32%		4.02%
Expected long-term return on plan assets		7.25%		7.25%		7.50%		n/a		n/a		n/a
Rate of compensation increase		scaled *		scaled *		scaled *		n/a		n/a		n/a

* Graded scale, declining from 7.00% at age 20 to 2.00% at age 60



	1% Decrease		Assumed		1% Increase
(in thousands)	in Rates		Rates		in Rates
Aggregated service and interest cost	$	722	$	797	$	889
Postretirement benefit obligation		20,964		23,036		25,564



	December 31, 2017
Fair Value Measurements by Asset Category / Fund		Level 1		Level 2		Level 3	Total
(in thousands)
Cash and equivalents	$	5,496	$	—	$	—	$	5,496
Total cash and cash equivalents		5,496		—		—		5,496

Fixed income securities		—		113,169		162		113,331
Mutual fund-fixed income		31,839		—		—		31,839
Total fixed income		31,839		113,169		162		145,170

Domestic and foreign stock		102,416		6		—		102,422
Mutual funds-equity		168,299		—		—		168,299
Total equity		270,715		6		—		270,721

Real assets fund		—		—		—		—
Total assets at fair value		308,050		113,175		162		421,387
Common trust funds (fixed income)		—		—		—		114,068
Common trust fund (real assets)		—		—		—		28,910
Total	$	308,050	$	113,175	$	162	$	564,365



	December 31, 2016
Fair Value Measurements by Asset Category / Fund		Level 1		Level 2		Level 3		Total
(in thousands)
Cash and equivalents	$	15,568	$	—	$	—	$	15,568
Total cash and cash equivalents		15,568		—		—		15,568

Fixed income securities		—		136,085		—		136,085
Mutual fund-fixed income		48,805		—		—		48,805
Total fixed income		48,805		136,085		—		184,890

Domestic and foreign stock		104,455		6		—		104,461
Mutual funds-equity		157,630		—		—		157,630
Total equity		262,085		6		—		262,091

Real assets fund		27,690		—		—		27,690
Total assets at fair value		354,148		136,091		—		490,239
Common trust fund (fixed income)		—		—		—		25,316
Total	$	354,148	$	136,091	$	—	$	515,555