Benefit Plans (Tables)

6 Months Ended

Jun. 30, 2019

Benefit plans

Schedule of components of net periodic benefit cost

	Income line item where recognized in	Pension Benefits				Other Benefits
(dollars in thousands)	the consolidated statements of income	2019		2018		2019		2018
Three Months Ended June 30,
Service cost	Salaries and employee benefits	$	17	$	174	$	159	$	213
Interest cost	Other noninterest expense		2,044		1,795		206		184
Expected return on plan assets	Other noninterest expense		(1,195)		(1,239)		—		—
Prior service credit	Other noninterest expense		—		—		(107)		(107)
Recognized net actuarial loss	Other noninterest expense		1,564		1,609		(76)		—
Total net periodic benefit cost		$	2,430	$	2,339	$	182	$	290
Six Months Ended June 30,
Service cost	Salaries and employee benefits	$	34	$	348	$	318	$	425
Interest cost	Other noninterest expense		4,088		3,589		412		369
Expected return on plan assets	Other noninterest expense		(2,390)		(2,479)		—		—
Prior service credit	Other noninterest expense		—		—		(214)		(214)
Recognized net actuarial loss	Other noninterest expense		3,128		3,220		(152)		—
Total net periodic benefit cost		$	4,860	$	4,678	$	364	$	580