COMPONENTS OF QUARTERLY AND YEAR TO DATE NET PERIODIC BENEFIT COSTS

The components of net periodic expense for the Corporation’s pension and other benefit plans for the periods indicated are as follows (in thousands):



	Three Months Ended September 30,						Nine Months Ended September 30,
	2017			2016			2017			2016
Qualified Pension Plan
Service cost, benefits earned during the period	$	—		$	298		$	—		$	892
Interest cost on projected benefit obligation	403			470			1,209			1,410
Expected return on plan assets	(785		)	(756		)	(2,355		)	(2,267		)
Amortization of unrecognized transition obligation	—			—			—			—
Amortization of unrecognized prior service cost	—			1			—			5
Amortization of unrecognized net loss	58			383			174			1,150
Net periodic pension cost (benefit)	$	(324	)	$	396		$	(972	)	$	1,190

Supplemental Pension Plan
Service cost, benefits earned during the period	$	—		$	11		$	—		$	32
Interest cost on projected benefit obligation	12			13			36			39
Expected return on plan assets	—			—			—			—
Amortization of unrecognized prior service cost	—			—			—			—
Amortization of unrecognized net loss	1			6			3			19
Net periodic supplemental pension cost	$	13		$	30		$	39		$	90

Postretirement Plan, Medical and Life
Service cost, benefits earned during the period	$	—		$	11		$	—		$	35
Interest cost on projected benefit obligation	3			18			11			53
Expected return on plan assets	—			—			—			—
Amortization of unrecognized prior service cost	(55		)	(23		)	(165		)	(72		)
Amortization of unrecognized net loss	29			7			87			19
Net periodic postretirement, medical and life cost (benefit)	$	(23	)	$	13		$	(67	)	$	35