Benefit Plans (Tables)

9 Months Ended

Sep. 30, 2017

Supplemental Retirement Plan

Benefit plans

Schedule of components of net periodic benefit cost

	Three Months Ended				Nine Months Ended
	September 30,				September 30,
	2017		2016		2017		2016
	(Dollars in thousands)
Components of net periodic benefit cost:
Service cost	$	81	$	134	$	243	$	400
Interest cost		259		259		777		777
Amortization of net actuarial loss		69		60		207		180
Net periodic benefit cost	$	409	$	453	$	1,227	$	1,357

Split-Dollar Life Insurance Benefit Plan

Benefit plans

Schedule of change in projected benefit obligation

	September 30,		December 31,
	2017		2016
	(Dollars in thousands)
Change in projected benefit obligation:
Projected benefit obligation at beginning of year	$	6,301	$	6,215
Interest cost		182		248
Actuarial gain		—		(162)
Projected benefit obligation at end of period	$	6,483	$	6,301

Schedule of amounts recognized in accumulated other comprehensive loss

	September 30,		December 31,
	2017		2016
	(Dollars in thousands)
Net actuarial loss	$	2,246	$	2,126
Prior transition obligation		1,261		1,328
Accumulated other comprehensive loss	$	3,507	$	3,454

Schedule of components of net periodic benefit cost

	Three Months Ended				Nine Months Ended
	September 30,				September 30,
	2017		2016		2017		2016
	(Dollars in thousands)
Amortization of prior transition obligation	$	(18)	$	(13)	$	(53)	$	(39)
Interest cost		61		62		182		186
Net periodic benefit cost	$	43	$	49	$	129	$	147