Retirement Plans (Tables)

3 Months Ended

Mar. 31, 2019

Compensation And Retirement Disclosure [Abstract]

Summary of Components of Net Periodic Pension Cost

The following table summarizes the components of net periodic pension cost for the quarters ended March 31, 2019 and 2018.

	Three Months Ended
	March 31, 2019		March 31, 2018
(Dollars in thousands)
Interest cost	$	286	$	272
Net amortization		52		109
Net periodic pension cost	$	338	$	381