EMPLOYEE BENEFIT PLANS (Tables)

6 Months Ended

Jun. 30, 2019

Pension and Other Postretirement Benefits Cost (Reversal of Cost) [Abstract]

Components of the Net Periodic Benefit Cost

Components of the net periodic benefit cost of PLC’s defined benefit pension plan for the three and six months ended June 30, 2019 and 2018, are as follows: 

	For The Three Months Ended June 30,										For The Six Months Ended June 30,
	2019					2018					2019					2018
	Qualified Pension Plan			Nonqualified Excess Pension Plan		Qualified Pension Plan			Nonqualified Excess Pension Plan		Qualified Pension Plan			Nonqualified Excess Pension Plan		Qualified Pension Plan			Nonqualified Excess Pension Plan
	(Dollars In Thousands)
Service cost — benefits earned during the period	$	3,114		$	285	$	3,441		$	387	$	6,228		$	570	$	6,882		$	774
Interest cost on projected benefit obligation	2,778			371		2,397			359		5,556			742		4,794			718
Expected return on plan assets	(4,463		)	—		(4,026		)	—		(8,926		)	—		(8,052		)	—
Amortization of actuarial loss	—			74		—			265		—			148		—			530
Preliminary net periodic benefit cost	1,429			730		1,812			1,011		2,858			1,460		3,624			2,022
Settlement/curtailment expense	—			—		—			—		—			—		—			—
Total net periodic benefit costs	$	1,429		$	730	$	1,812		$	1,011	$	2,858		$	1,460	$	3,624		$	2,022