PENSION AND OTHER POSTRETIREMENT BENEFIT PLANS (Tables)

3 Months Ended

Mar. 31, 2012

PENSION AND OTHER POSTRETIREMENT BENEFIT PLANS

Summary of the components of net periodic benefit cost

	Three Months Ended March 31
	Nonunion Defined						Supplemental				Postretirement
	Benefit Pension Plan						Benefit Pension Plan				Health Benefit Plan
	2012			2011			2012		2011		2012			2011
	($ thousands)
Service cost	$	2,297		$	2,164		$	—	$	—	$	79		$	56
Interest cost	2,173			2,489			52		97		187			195
Expected return on plan assets	(3,016		)	(3,146		)	—		—		—			—
Amortization of prior service credit	—			—			—		—		(48		)	(48		)
Amortization of net actuarial loss and other	2,692			1,730			51		82		104			28
Net periodic benefit cost	$	4,146		$	3,237		$	103	$	179	$	322		$	231