Retirement Plans (Tables)

3 Months Ended

Mar. 31, 2012

Retirement Plans [Abstract]

Net Periodic Benefit Cost

The following tables provide the components of net periodic benefit cost:

	Pension Benefits
		For the three months ended
					March 31,
		2012				2011
($ in thousands)
Components of net periodic pension benefit cost
Service cost		$	10,492			$	9,615
Interest cost on projected benefit obligation			19,658				21,172
Expected return on plan assets			(24,089	)			(25,589	)
Amortization of prior service cost /(credit)			(50	)			(50	)
Amortization of unrecognized loss			7,787				4,435
Net periodic pension benefit cost		$	13,798			$	9,583
	Postretirement Benefits
	Other Than Pensions (OPEB)
		For the three months ended
		March 31,
			2012				2011
($ in thousands)
Components of net periodic postretirement benefit cost
Service cost		$	2,555			$	4,228
Interest cost on projected benefit obligation			4,460				6,328
Expected return on plan assets			(55	)			(82	)
Amortization of prior service cost/(credit)			(2,503	)			(2,550	)
Amortization of unrecognized loss			1,911				1,499
Net periodic postretirement benefit cost		$	6,368			$	9,423