Retirement Plans (Tables)

6 Months Ended

Jun. 30, 2012

Retirement Plans [Abstract]

Net Periodic Benefit Cost

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

	Pension Benefits						Pension Benefits
	For the three months ended						For the six months ended
	June 30,						June 30,
	2012			2011			2012			2011
($ in thousands)
Components of net periodic pension benefit cost
Service cost	$	10,492		$	9,615		$	20,984		$	19,230
Interest cost on projected benefit obligation		19,658			21,172			39,316			42,344
Expected return on plan assets		(24,089	)		(25,589	)		(48,178	)		(51,178	)
Amortization of prior service cost /(credit)		(50	)		(50	)		(100	)		(100	)
Amortization of unrecognized loss		7,787			4,435			15,574			8,870
Net periodic pension benefit cost	$	13,798		$	9,583		$	27,596		$	19,166

		Postretirement Benefits						Postretirement Benefits
		Other Than Pensions (OPEB)						Other Than Pensions (OPEB)
		For the three months ended						For the six months ended
		June 30,						June 30,
		2012			2011			2012			2011
($ in thousands)
Components of net periodic postretirement benefit cost
Service cost	$	2,555		$	4,228		$	5,110		$	8,456
Interest cost on projected benefit obligation		4,460			6,328			8,920			12,656
Expected return on plan assets		(55	)		(82	)		(110	)		(164	)
Amortization of prior service cost/(credit)		(2,503	)		(2,550	)		(5,006	)		(5,100	)
Amortization of unrecognized loss		1,911			1,499			3,822			2,998
Net periodic postretirement benefit cost	$	6,368		$	9,423		$	12,736		$	18,846