Retirement Plans and Other Postretirement Benefits (Tables)

12 Months Ended

Dec. 31, 2018

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)	2018			2017			2018			2017
Change in benefit obligation:
Benefit obligation at beginning of year	$	50,364		$	47,389		$	2,611		$	2,968
Service cost	560			524			88			48
Interest cost	1,760			1,927			92			118
Actuarial (gain) loss	(3,205		)	3,169			(404		)	(409		)
Benefits paid	(2,611		)	(2,645		)	(104		)	(114		)
Benefit obligation at end of year	$	46,868		$	50,364		$	2,283		$	2,611
Change in plan assets:
Fair value of plan assets at beginning of year	$	46,753		$	41,418		$	—		$	—
Actual (loss) return on plan assets	(1,923		)	5,799			—			—
Benefits paid	(2,611		)	(2,645		)	(104		)	(114		)
Employer contribution and non-qualified benefit payments	3,160			2,181			104			114
Fair value of plan assets at end of year	$	45,379		$	46,753		$	—		$	—
Funded status	(1,489		)	(3,611		)	(2,283		)	(2,611		)
Unrecognized net actuarial loss (gain)	22,141			21,256			(92		)	316
Unrecognized prior service costs	(181		)	(464		)	—			—
Net amount recognized	$	20,471		$	17,181		$	(2,375	)	$	(2,295	)

Information for Pension Plans with Accumulated Benefit Obligation in Excess of Plan Assets

Components of Net Periodic Benefit Cost (Income)

Components of net periodic benefit cost were as follows:

	Retirement Plans									Other Post Retirement Benefits
(Dollars in thousands)	2018			2017			2016			2018		2017		2016
Service cost	$	560		$	524		$	661		$	88	$	48	$	46
Interest cost	1,760			1,927			2,071			92		118		133
Expected (loss) return on plan assets	(3,287		)	(3,074		)	(3,041		)	—		—		—
Amortization of net actuarial loss	1,120			1,185			1,296			4		42		25
Accretion of prior service cost	(283		)	(282		)	(283		)	—		—		—
Settlement cost	—			—			1,434			—		—		—
Net periodic benefit (income) cost	$	(130	)	$	280		$	2,138		$	184	$	208	$	204

Expected Amortization Expense

(Dollars in thousands)	Retirement Plans			Other Postretirement Benefits
Expected amortization expense for 2019:
Amortization of net actuarial loss	$	1,175		$	—
Accretion of prior service cost	(181		)	—

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:
2019	$	2,836	$	89
2020	2,839		90
2021	2,892		92
2022	2,898		94
2023	2,964		97
Years 2024-2028	14,946		540

Weighted-Average Assumptions Used to Determine Benefit Obligations

Weighted-average assumptions used to determine benefit obligations at December 31, 2018 and 2017 were as follows:

	Retirement Plans				Other Postretirement Benefits
	2018		2017		2018		2017
Assumed discount rate	4.2	%	3.6	%	4.2	%	3.6	%
Assumed salary increase rate	3.0		3.0		—		—

The benefit obligation for all plans at December 31, 2018 was based on the RP-2014 mortality table using the projection scale MP-2018 published by the Society of Actuaries.

Weighted-average assumptions used to determine net periodic costs for the years ended December 31, 2018 and 2017 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
	2018		2017		2018		2017
Assumed discount rate	3.6	%	4.0	%	3.6	%	4.0	%
Assumed long-term rate of investment return	7.0		7.5		—		—
Assumed salary increase rate	3.0		3.0		—		—

Summary of Corporation's Pension Plan Asset Allocation

The Corporation's pension plan asset allocation at December 31, 2018 and 2017, by asset category was as follows:

	Percentage of Plan Assets at December 31,
	2018		2017
Asset Category:
Equity securities	60	%	64	%
Debt securities	39		35
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 17, “Fair Value Disclosures.”

	Fair Value Measurements at December 31,
(Dollars in thousands)	2018		2017
Level 1:
Mutual funds	$	28,360	$	31,144
Short-term investments	666		515
Level 2:
U.S. government obligations	6,167		4,910
Corporate bonds	6,031		5,974
Level 3:
Certificates of deposit	4,155		4,210
Total fair value of plan assets	$	45,379	$	46,753

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, 2018 and 2017:

(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
(Dollars in thousands)	Balance at December 31, 2016		Total Unrealized (Losses) or Gains		Total Realized Gains or (Losses)		Purchases		Maturities/ Redemptions			Balance at December 31, 2017
Certificates of deposit	$	4,565	$	—	$	—	$	535	$	(890	)	$	4,210
Total Level 3 assets	$	4,565	$	—	$	—	$	535	$	(890	)	$	4,210