Defined Benefit Plans (Tables)

3 Months Ended

Mar. 31, 2015

Defined Benefit Pension Plans and Defined Benefit Postretirement Plans Disclosure [Abstract]

Schedule of Costs of Retirement Plans

The components of net periodic pension and postretirement benefit costs for the three months ended March 31, 2015 and 2014 are as follows:

	Pension Plans						Other Postretirement Benefits
	Three months ended March 31,						Three months ended March 31,
	2015			2014			2015			2014
	(dollars in thousands)
Service costs	$	240		$	190		$	—		$	—
Interest costs	420			440			10			10
Expected return on plan assets	(520		)	(520		)	—			—
Amortization of net (gain)/loss	380			280			(10		)	(20		)
Net periodic benefit cost	$	520		$	390		$	—		$	(10	)