Pension and Non-pension Post-retirement Benefits (Tables)

6 Months Ended

Jun. 30, 2018

Defined Benefit Pension Plan

Defined Benefit Plan Disclosure [Line Items]

Schedule of Net Benefit Costs [Table Text Block]

The components of our net pension expense, including the SERP, are as follows:

Three months ended June 30,	U.S. Plans						Non-U.S. Plans						Total
(dollars in thousands)	2018			2017			2018			2017			2018			2017
Service cost	$	1,025		$	883		$	284		$	277		$	1,309		$	1,160
Interest cost	3,142			3,442			741			701			3,883			4,143
Expected return on plan assets	(5,669		)	(5,623		)	—			—			(5,669		)	(5,623		)
Amortization of unrecognized:
Prior service cost (credit)	1			59			(50		)	(52		)	(49		)	7
Actuarial loss	1,599			1,265			154			152			1,753			1,417
Pension expense	$	98		$	26		$	1,129		$	1,078		$	1,227		$	1,104
Six months ended June 30,	U.S. Plans						Non-U.S. Plans						Total
(dollars in thousands)	2018			2017			2018			2017			2018			2017
Service cost	$	2,004		$	1,958		$	576		$	528		$	2,580		$	2,486
Interest cost	6,307			6,892			1,504			1,338			7,811			8,230
Expected return on plan assets	(11,329		)	(11,240		)	—			—			(11,329		)	(11,240		)
Amortization of unrecognized:
Prior service cost (credit)	1			118			(101		)	(99		)	(100		)	19
Actuarial loss	3,236			2,617			313			290			3,549			2,907
Pension expense	$	219		$	345		$	2,292		$	2,057		$	2,511		$	2,402

Non-Pension Post-retirement Benefit Plans

Defined Benefit Plan Disclosure [Line Items]

Schedule of Net Benefit Costs [Table Text Block]

The provision for our non-pension, post-retirement, benefit expense consists of the following:

Three months ended June 30,	U.S. Plans						Non-U.S. Plans						Total
(dollars in thousands)	2018			2017			2018			2017			2018			2017
Service cost	$	151		$	96		$	—		$	—		$	151		$	96
Interest cost	455			471			10			11			465			482
Amortization of unrecognized:
Prior service cost (credit)	(70		)	(51		)	—			—			(70		)	(51		)
Actuarial loss / (gain)	(53		)	(154		)	(17		)	(13		)	(70		)	(167		)
Non-pension post-retirement benefit expense	$	483		$	362		$	(7	)	$	(2	)	$	476		$	360
Six months ended June 30,	U.S. Plans						Non-U.S. Plans						Total
(dollars in thousands)	2018			2017			2018			2017			2018			2017
Service cost	$	302		$	316		$	—		$	—		$	302		$	316
Interest cost	911			1,052			20			22			931			1,074
Amortization of unrecognized:
Prior service cost (credit)	(141		)	(101		)	—			—			(141		)	(101		)
Actuarial loss / (gain)	(105		)	(129		)	(33		)	(26		)	(138		)	(155		)
Non-pension post-retirement benefit expense	$	967		$	1,138		$	(13	)	$	(4	)	$	954		$	1,134