Employee Benefit Plans (Tables)

9 Months Ended

Sep. 30, 2017

BancShares Plan

For the three and nine months ended September 30, 2017 and 2016, the components of net periodic benefit cost are as follows:



	Three months ended September 30						Nine months ended September 30
(Dollars in thousands)	2017			2016			2017			2016
Service cost	$	3,180		$	3,153		$	9,490		$	9,463
Interest cost	7,283			7,218			21,732			21,668
Expected return on assets	(10,589		)	(9,155		)	(31,594		)	(27,481		)
Amortization of prior service cost	53			54			158			158
Amortization of net actuarial loss	2,214			1,714			6,641			5,144
Net periodic benefit cost	$	2,141		$	2,984		$	6,427		$	8,952

Bancorporation Plan

For the three and nine months ended September 30, 2017 and 2016, the components of net periodic benefit cost are as follows:



	Three months ended September 30						Nine months ended September 30
(Dollars in thousands)	2017			2016			2017			2016
Service cost	$	569		$	642		$	1,910		$	1,925
Interest cost	1,624			1,694			4,989			5,081
Expected return on assets	(2,783		)	(2,775		)	(8,375		)	(8,325		)
Amortization of net actuarial loss	63			—			491			—
Net periodic benefit cost	$	(527	)	$	(439	)	$	(985	)	$	(1,319	)