Retirement Plans and Other Postretirement Benefits (Tables)

12 Months Ended

Dec. 31, 2019

Retirement Benefits [Abstract]

Summary of Retirement Plans and Other Postretirement Benefits

Information with respect to the Retirement Plans and Other Postretirement Benefits follows:

	Retirement Plans				Other Postretirement Benefits
(Dollars in thousands)	2019		2018		2019		2018
Change in benefit obligation:
Benefit obligation at beginning of year	$	46,868	$	50,364	$	2,283	$	2,611
Service cost	436		560		67		88
Interest cost	1,905		1,760		94		92
Actuarial loss (gain)	7,104		(3,205)		731		(404)
Benefits paid	(2,628)		(2,611)		(106)		(104)
Benefit obligation at end of year	$	53,685	$	46,868	$	3,069	$	2,283
Change in plan assets:
Fair value of plan assets at beginning of year	$	45,379	$	46,753	$	—	$	—
Actual return (loss) on plan assets	8,696		(1,923)		—		—
Benefits paid	(2,628)		(2,611)		(106)		(104)
Employer contribution and non-qualified benefit payments	160		3,160		106		104
Fair value of plan assets at end of year	$	51,607	$	45,379	$	—	$	—
Funded status	(2,078)		(1,489)		(3,069)		(2,283)
Unrecognized net actuarial loss (gain)	22,433		22,141		638		(92)
Unrecognized prior service costs	—		(181)		—		—
Net amount recognized	$	20,355	$	20,471	$	(2,431)	$	(2,375)

Components of Net Periodic Benefit Cost (Income)

Components of net periodic benefit cost were as follows: 

	Retirement Plans						Other Postretirement Benefits
(Dollars in thousands)	2019		2018		2017		2019		2018		2017
Service cost	$	436	$	560	$	524	$	67	$	88	$	48
Interest cost	1,905		1,760		1,927		94		92		118
Expected loss on plan assets	(3,061)		(3,287)		(3,074)		—		—		—
Amortization of net actuarial loss	1,176		1,120		1,185		—		4		42
Accretion of prior service cost	(181)		(283)		(282)		—		—		—
Net periodic benefit cost (income)	$	275	$	(130)	$	280	$	161	$	184	$	208

Expected Amortization Expense

(Dollars in thousands)	Retirement Plans		Other Postretirement Benefits
Expected amortization expense for 2020:
Amortization of net actuarial loss	$	1,156	$	25
Accretion of prior service cost	—		—

Summary of Benefit Payments Expected to be Paid

The following benefits payments, which reflect expected future service, as appropriate, are expected to be paid:

(Dollars in thousands)	Retirement Plans		Other Postretirement Benefits
For the fiscal year ending:
2020	$	2,845	$	89
2021	2,920		92
2022	2,930		94
2023	2,996		97
2024	3,013		102
Years 2025-2029	15,122		557

Weighted-Average Assumptions Used to Determine Benefit Obligations

Weighted-average assumptions used to determine benefit obligations at December 31, 2019 and 2018 were as follows:

	Retirement Plans				Other Postretirement Benefits
	2019		2018		2019		2018
Assumed discount rate	3.2	%	4.2	%	3.2	%	4.2	%
Assumed salary increase rate (based on age)	3% - 6%		3% - 6%		—		—

The benefit obligation for all plans at December 31, 2019 was based on the Pri-2012 White Collar Mortality Table projected to 2029 using scale MP-2019 published by the Society of Actuaries.

Weighted-average assumptions used to determine net periodic costs for the years ended December 31, 2019 and 2018 were as follows. The discount rate was determined utilizing the FTSE Pension Discount Curve. Historical investment returns is the basis used to determine the overall expected long-term rate of return on assets.

	Retirement Plans				Other Postretirement Benefits
	2019		2018		2019		2018
Assumed discount rate	4.2	%	3.6	%	4.2	%	3.6	%
Assumed long-term rate of investment return	7.0	%	7.0	%	—		—
Assumed salary increase rate (based on age)	3% - 6%		3% - 6%		—		—

Summary of Corporation's Pension Plan Asset Allocation

The Corporation's pension plan asset allocation at December 31, 2019 and 2018, by asset category was as follows:

	Percentage of Plan Assets at December 31,
	2019		2018
Asset Category:
Equity securities	61	%	60	%
Debt securities	38		39
Other	1		1
Total	100	%	100	%

Major Categories of Assets in Corporation's Pension Plan

The major categories of assets in the Corporation’s pension plan at year-end are presented in the following table. Assets are segregated by the level of the valuation inputs within the fair value hierarchy described in Note 18, “Fair Value Disclosures.”

	Fair Value Measurements at December 31,
(Dollars in thousands)	2019		2018
Level 1:
Mutual funds	$	34,332	$	28,360
Short-term investments	1,068		666
Level 2:
U.S. government obligations	6,167		6,167
Corporate bonds	6,540		6,031
Level 3:
Certificates of deposit	3,500		4,155
Total fair value of plan assets	$	51,607	$	45,379

Reconciliation of Beginning and Ending Balances for Measurements in Hierarchy Level 3

The following table provides a reconciliation of the beginning and ending balances for measurements in hierarchy Level 3 at December 31, 2019 and 2018:

(Dollars in thousands)	Balance at December 31, 2018		Total Unrealized (Losses) or Gains		Total Realized Gains or (Losses)		Purchases		Maturities/ Redemptions		Balance at December 31, 2019
Certificates of deposit	$	4,155	$	110	$	—	$	600	$	(1,365)	$	3,500
Total Level 3 assets	$	4,155	$	110	$	—	$	600	$	(1,365)	$	3,500
(Dollars in thousands)	Balance at December 31, 2017		Total Unrealized (Losses) or Gains		Total Realized Gains or (Losses)		Purchases		Maturities/ Redemptions		Balance at December 31, 2018
Certificates of deposit	$	4,210	$	—	$	—	$	845	$	(900)	$	4,155
Total Level 3 assets	$	4,210	$	—	$	—	$	845	$	(900)	$	4,155