Pension Benefits and Other Postretirement Benefit Plans (Tables)

3 Months Ended

Mar. 31, 2020

Defined Benefit Plan [Abstract]

Components of Net Periodic Benefit Cost

The components of net periodic benefit (credit) cost were as follows:

	Pension Benefits				Other Postretirement Benefits
	Three Months Ended				Three Months Ended
	March 31,				March 31,
(Dollars in thousands)	2020		2019		2020		2019
Service cost	$	—	$	—	$	17	$	18
Interest cost	231		1,784		10		15
Expected return of plan assets	(393)		(2,192)		—		—
Amortization of prior service credit	—		—		(28)		(253)
Amortization of net loss	114		454		—		—
Net periodic benefit (credit) cost	$	(48)	$	46	$	(1)	$	(220)