Retirement Benefits (Tables)

6 Months Ended

Jun. 30, 2011

Pension Benefits

Components of Net Periodic Benefit Costs

The components of the net periodic pension benefit costs are as follows:

	Three Months Ended						Six Months Ended
	June 30,			June 30,			June 30,			June 30,
	2011			2010			2011			2010
	(Dollars in thousands)
Service cost	$	3,740		$	3,075		$	7,510		$	6,785
Interest cost		7,144			6,995			14,314			14,020
Expected return on plan assets		(10,186	)		(9,377	)		(20,400	)		(16,793	)
Amortization of prior service cost		510			515			1,021			1,033
Amortization of actuarial losses		1,993			2,282			3,985			4,199
Net periodic benefit cost	$	3,201		$	3,490		$	6,430		$	9,244

Other Postretirement Benefits

Components of Net Periodic Benefit Costs

The components of the net periodic other postretirement benefits costs are as follows:

	Three Months Ended						Six Months Ended
	June 30,			June 30,			June 30,			June 30,
	2011			2010			2011			2010
	(Dollars in thousands)
Service cost	$	259		$	244		$	518		$	466
Interest cost		658			695			1,315			1,403
Amortization of prior service credit		(643	)		(641	)		(1,285	)		(1,283	)
Amortization of actuarial losses		142			53			284			143
Net periodic benefit cost	$	416		$	351		$	832		$	729