Defined Benefit Pension Plans (Tables)

3 Months Ended

Mar. 31, 2021

Retirement Benefits [Abstract]

Components of Net Periodic Benefit Cost

The following table presents components of net periodic benefit cost and other amounts recognized in other comprehensive income (loss), on a pre-tax basis:

(Dollars in thousands)	Qualified Pension Plan		Non-Qualified Retirement Plans
Three months ended March 31,	2021	2020	2021	2020
Net Periodic Benefit Cost:
Service cost (1)	$592	$541	$52	$43
Interest cost (2)	645	626	84	116
Expected return on plan assets (2)	(1,204)	(1,135)	—	—
Recognized net actuarial loss (2)	387	396	158	140
Net periodic benefit cost	$420	$428	$294	$299

(1)Included in salaries and employee benefits expense in the Unaudited Consolidated Statements of Income.

(2)Included in other expenses in the Unaudited Consolidated Statements of Income.

Schedule of Assumptions Used for Net Periodic Benefit Cost

The following table presents the measurement date and weighted-average assumptions used to determine net periodic benefit cost:

	Qualified Pension Plan		Non-Qualified Retirement Plans
For the three months ended March 31,	2021	2020	2021	2020
Measurement date	Dec 31, 2020	Dec 31, 2019	Dec 31, 2020	Dec 31, 2019
Equivalent single discount rate for benefit obligations	2.71%	3.42%	2.51%	3.30%
Equivalent single discount rate for service cost	2.86	3.54	2.94	3.62
Equivalent single discount rate for interest cost	2.16	3.07	1.97	2.93
Expected long-term return on plan assets	5.75	5.75	N/A	N/A
Rate of compensation increase	3.75	3.75	3.75	3.75