Retirement Benefits - Reconciliation Of Changes In Benefit Obligations And Fair Value Of Plan Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
CHANGE IN BENEFIT OBLIGATION
Other	$ 0
CHANGE IN PLAN ASSETS
Fair value of plan assets at January 1	98,242
Other	0
Fair value of plan assets at December 31	106,274	$ 98,242
Other noncurrent liabilities	(93,604)	(76,190)
U.S. Plans
CHANGE IN BENEFIT OBLIGATION
Obligation at January 1	98,476	102,312
Service cost	1,016	1,279	$ 1,162
Interest cost	3,043	3,770	4,037
Plan amendments	0	113
Benefits paid	(3,140)	(3,985)
Actuarial loss (gain)	1,987	(5,013)
Currency translation	0	0
Settlements	(11,126)	0
Acquisition/Divestiture	0	0
Other	0	0
Obligation at December 31	90,256	98,476	102,312
CHANGE IN PLAN ASSETS
Fair value of plan assets at January 1	77,575	79,687
Actual return on plan assets	6,740	(2,587)
Employer contributions	3,639	4,460
Benefits paid	(3,140)	(3,985)
Currency translation	0	0
Settlements	(11,126)	0
Acquisition/Divestiture	0	0
Other	0	0
Fair value of plan assets at December 31	73,688	77,575	79,687
Funded status at December 31	(16,568)	(20,901)
Current liabilities	(729)	(743)
Other noncurrent liabilities	(15,839)	(20,158)
Net liability at December 31	(16,568)	(20,901)
Non-U.S. Plans
CHANGE IN BENEFIT OBLIGATION
Obligation at January 1	58,063	69,488
Service cost	1,627	1,506	1,331
Interest cost	1,429	1,734	2,345
Plan amendments	0	0
Benefits paid	(2,023)	(2,448)
Actuarial loss (gain)	6,844	(6,909)
Currency translation	(6,988)	(5,308)
Settlements	(819)	0
Acquisition/Divestiture	29,491	0
Other	140	0
Obligation at December 31	87,764	58,063	69,488
CHANGE IN PLAN ASSETS
Fair value of plan assets at January 1	20,645	22,152
Actual return on plan assets	2,470	205
Employer contributions	1,974	1,837
Benefits paid	(2,023)	(2,448)
Currency translation	(4,108)	(1,101)
Settlements	(819)	0
Acquisition/Divestiture	14,307	0
Other	140	0
Fair value of plan assets at December 31	32,586	20,645	22,152
Funded status at December 31	(55,178)	(37,418)
Current liabilities	(1,005)	(875)
Other noncurrent liabilities	(54,173)	(36,543)
Net liability at December 31	(55,178)	(37,418)
Other Postretirement Benefit Plans
CHANGE IN BENEFIT OBLIGATION
Obligation at January 1	20,400	22,855
Service cost	601	673	714
Interest cost	811	833	932
Plan amendments	0	0
Benefits paid	(718)	(622)
Actuarial loss (gain)	(1,990)	(2,966)
Currency translation	52	(373)
Settlements	0	0
Acquisition/Divestiture	5,480	0
Other	0	0
Obligation at December 31	24,636	20,400	22,855
CHANGE IN PLAN ASSETS
Fair value of plan assets at January 1	0	0
Actual return on plan assets	0	0
Employer contributions	718	622
Benefits paid	(718)	(622)
Currency translation	0	0
Settlements	0	0
Acquisition/Divestiture	0	0
Other	0	0
Fair value of plan assets at December 31	0	0	$ 0
Funded status at December 31	(24,636)	(20,400)
Current liabilities	(1,044)	(911)
Other noncurrent liabilities	(23,592)	(19,489)
Net liability at December 31	$ (24,636)	$ (20,400)