Defined Benefit Plans (Tables)

6 Months Ended

Jun. 30, 2016

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 and six months ended June 30, 2016 and 2015 are as follows (dollars in thousands):

	Pension Plans												Other Postretirement Benefits
	Three months ended June 30,						Six months ended June 30,						Three months ended June 30,						Six months ended June 30,
	2016			2015			2016			2015			2016			2015			2016			2015
Service costs	$	240		$	230		$	490		$	470		$	—		$	—		$	—		$	—
Interest costs	390			410			790			830			10			—			10			10
Expected return on plan assets	(420		)	(490		)	(840		)	(1,010		)	—			—			—			—
Amortization of prior service cost	10			10			10			10			—			—			—			—
Settlement/curtailment loss	—			2,750			—			2,750			—			—			—			—
Amortization of net (gain)/loss	240			360			470			740			(20		)	(10		)	(30		)	(20		)
Net periodic benefit cost	$	460		$	3,270		$	920		$	3,790		$	(10	)	$	(10	)	$	(20	)	$	(10	)