Retirement Benefits - Pretax Amounts Recognized in Accumulated Other Comprehensive Income Loss (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2019 USD ($)
Pension Benefits | U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Net gain (loss) in current year	$ (1,265)
Prior service cost	0
Amortization of prior service cost (credit)	15
Amortization of net loss (gain)	2,312
Exchange rate effect on amounts in OCI	0
Total	1,062
Pension Benefits | Non-U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Net gain (loss) in current year	(7,544)
Prior service cost	156
Amortization of prior service cost (credit)	6
Amortization of net loss (gain)	1,111
Exchange rate effect on amounts in OCI	86
Total	(6,185)
Other Benefit Plans
Defined Benefit Plan Disclosure [Line Items]
Net gain (loss) in current year	161
Prior service cost	0
Amortization of prior service cost (credit)	(70)
Amortization of net loss (gain)	(565)
Exchange rate effect on amounts in OCI	26
Total	$ (448)