Benefit Plans (Tables)

6 Months Ended

Jun. 30, 2018

Supplemental Retirement Plan

Benefit plans

Schedule of components of net periodic benefit cost

	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2018		2017		2018		2017
	(Dollars in thousands)
Components of net periodic benefit cost:
Service cost	$	62	$	81	$	124	$	162
Interest cost		237		259		474		518
Amortization of net actuarial loss		73		69		146		138
Net periodic benefit cost	$	372	$	409	$	744	$	818

Split-Dollar Life Insurance Benefit Plan

Benefit plans

Schedule of change in projected benefit obligation

	June 30,		December 31,
	2018		2017
	(Dollars in thousands)
Change in projected benefit obligation:
Projected benefit obligation at beginning of year	$	6,711	$	6,301
Interest cost		113		243
Actuarial loss		—		167
Projected benefit obligation at end of period	$	6,824	$	6,711

Schedule of amounts recognized in accumulated other comprehensive loss

	June 30,		December 31,
	2018		2017
	(Dollars in thousands)
Net actuarial loss	$	2,530	$	2,453
Prior transition obligation		1,194		1,238
Accumulated other comprehensive loss	$	3,724	$	3,691

Schedule of components of net periodic benefit cost

	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2018		2017		2018		2017
	(Dollars in thousands)
Amortization of prior transition obligation	$	(16)	$	(17)	$	(32)	$	(35)
Interest cost		56		60		113		121
Net periodic benefit cost	$	40	$	43	$	81	$	86