POSTRETIREMENT MEDICAL BENEFITS AND PENSION (Tables)

9 Months Ended

Sep. 30, 2015

Postretirement Medical Benefits

Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]

Components of net periodic benefit cost

The components of net periodic postretirement medical benefit cost are as follows:

	Three Months Ended September 30,				Nine Months Ended September 30,
	2015		2014		2015		2014
	(In thousands)				(In thousands)
Components of net periodic benefit cost:
Service cost	$	1,054	$	822	$	3,163	$	2,467
Interest cost	2,907		3,203		8,722		9,610
Amortization of deferred items	327		4		981		13
Total net periodic benefit cost	$	4,288	$	4,029	$	12,866	$	12,090

The following table shows the net periodic postretirement medical benefit costs that relate to current and former mining operations:

	Three Months Ended September 30,				Nine Months Ended September 30,
	2015		2014		2015		2014
	(In thousands)				(In thousands)
Former mining operations	$	2,034	$	2,402	$	6,103	$	7,210
Current operations	2,254		1,627		6,763		4,880
Total net periodic benefit cost	$	4,288	$	4,029	$	12,866	$	12,090

Pension

Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]

Components of net periodic benefit cost

The Company incurred net periodic benefit costs of providing these pension benefits as follows:

	Three Months Ended September 30,						Nine Months Ended September 30,
	2015			2014			2015			2014
	(In thousands)						(In thousands)
Components of net periodic benefit cost:
Service cost	$	436		$	500		$	1,318		$	1,500
Interest cost	1,831			1,747			5,780			5,240
Expected return on plan assets	(2,435		)	(2,154		)	(7,744		)	(6,461		)
Settlements	(1,529		)	—			(1,874		)	—
Amortization of deferred items	1,059			359			3,301			1,078
Total net periodic pension cost	$	(638	)	$	452		$	781		$	1,357