Retirement Benefit Plans Part 2 (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)
Defined Benefit Plans and Other Postretirement Benefit Plans
Number of active employees participating in U.S. Pension Plan	69
Plans with accumulated benefit obligation in excess of plan assets
Accumulated benefit obligation	$ 2,616	$ 13,872
Fair value of plan assets	0	9,989
Plans with projected benefit obligation in excess of plan assets
Projected benefit obligation	2,616	14,207
Fair value of plan assets	0	9,989
Changes in accumulated other comprehensive income:
Total recognized in other comprehensive (income) loss	(4,121)	$ 5,382	$ (12,282)
Pension Benefits
Amounts that will be amortized from accumulated other comprehensive income (loss) in next fiscal year
Net actuarial loss	64
Prior service cost	$ 42
U.S. Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans
Number of participants in U.S. Pension Plan	361
Expected future employer contributions in the next fiscal year	$ 0
Weighted-average assumptions used to determine benefit obligation
Discount rate	4.08%	3.76%
Rate of compensation increase	3.00%	3.00%
Weighted-average assumptions used to determine net periodic benefit costs
Discount rate	3.76%	4.63%	3.79%
Expected long-term rate of return on plan assets	5.20%	5.70%	6.50%
Rate of compensation increase	3.00%	3.00%	3.00%
Accumulated benefit obligations
Accumulated benefit obligations	$ 41,537	$ 45,695
Change in benefit obligation:
Benefit obligation at beginning of year	47,027	43,653
Service cost	480	493	$ 690
Interest cost	1,711	1,964	1,803
Plan participants' contributions	0	0
Actuarial (gain) loss	(3,352)	5,907
Foreign currency	0	0
Benefits paid	(1,944)	(1,706)
Settlement	(2,148)	(3,284)
Benefit obligation at end of year	41,774	47,027	43,653
Change in fair value of plan assets and net accrued liabilities:
Fair value of plan assets at beginning of year	51,885	52,397
Actual return on plan assets	(933)	4,236
Employer contributions	341	242
Plan participants' contributions	0	0
Foreign exchange	0	0
Benefits paid	(1,944)	(1,706)
Settlement	(2,148)	(3,284)
Fair value of plan assets at end of year	47,201	51,885	52,397
Funded status at end of year	5,427	4,858
Amounts recognized in the Consolidated Balance Sheets consist of:
Noncurrent Other Assets	7,173	7,051
Current Liabilities	(243)	(185)
Long-Term Liabilities	(1,503)	(2,008)
Net accrued asset (liability)	5,427	4,858
Amounts recognized in Accumulated Other Comprehensive Loss consist of:
Prior service (cost) credit	(42)	(109)
Net actuarial loss	(5,127)	(5,993)
Accumulated Other Comprehensive Loss	(5,169)	(6,102)
Components of the net periodic benefit cost
Service cost	480	493	690
Interest cost	1,711	1,964	1,803
Expected return on plan assets	(2,613)	(2,683)	(2,911)
Amortization of net actuarial loss	835	147	1,751
Amortization of prior service cost (credit)	42	43	73
Foreign currency	0	0	0
Curtailment charge	25	0	0
Settlement credit	225	356	0
Net periodic benefit cost	705	320	1,406
Changes in accumulated other comprehensive income:
Net actuarial loss (gain)	195	4,353	(9,817)
Amortization of prior service (cost) credit	(67)	(43)	(73)
Amortization of net actuarial loss	(1,060)	(503)	(1,751)
Total recognized in other comprehensive (income) loss	(932)	3,807	(11,641)
Total recognized in net periodic benefit (cost) and other comprehensive (income) loss	(227)	$ 4,127	$ (10,235)
Expected future benefit payments
2016	2,296
2017	2,450
2018	2,594
2019	2,573
2020	2,637
2021 to 2025	13,582
Total	$ 26,132
U.S. Pension Plan | Debt Securities
Defined Benefit Plans and Other Postretirement Benefit Plans
Target allocation of investments	60.00%
U.S. Pension Plan | Equity Securities
Defined Benefit Plans and Other Postretirement Benefit Plans
Target allocation of investments	40.00%
U.S. Nonqualified Plan
Defined Benefit Plans and Other Postretirement Benefit Plans
Expected future employer contributions in the next fiscal year	$ 243
Non-U.S. Pension Benefits
Weighted-average assumptions used to determine benefit obligation
Discount rate	3.59%	3.38%
Rate of compensation increase	3.50%	3.50%
Weighted-average assumptions used to determine net periodic benefit costs
Discount rate	3.38%	4.33%	4.41%
Expected long-term rate of return on plan assets	4.40%	5.60%	4.70%
Rate of compensation increase	3.50%	4.50%	4.50%
Change in benefit obligation:
Benefit obligation at beginning of year	$ 12,014	$ 11,238
Service cost	153	155	$ 142
Interest cost	396	476	422
Plan participants' contributions	20	21
Actuarial (gain) loss	(718)	1,421
Foreign currency	681	815
Benefits paid	(301)	(482)
Settlement	0	0
Benefit obligation at end of year	10,883	12,014	11,238
Change in fair value of plan assets and net accrued liabilities:
Fair value of plan assets at beginning of year	9,989	9,733
Actual return on plan assets	1,232	974
Employer contributions	333	365
Plan participants' contributions	20	21
Foreign exchange	(582)	(622)
Benefits paid	(301)	(482)
Settlement	0	0
Fair value of plan assets at end of year	10,691	9,989	9,733
Funded status at end of year	(192)	(2,025)
Amounts recognized in the Consolidated Balance Sheets consist of:
Noncurrent Other Assets	678	0
Current Liabilities	(33)	(37)
Long-Term Liabilities	(837)	(1,988)
Net accrued asset (liability)	(192)	(2,025)
Amounts recognized in Accumulated Other Comprehensive Loss consist of:
Prior service (cost) credit	0	0
Net actuarial loss	(111)	(1,682)
Accumulated Other Comprehensive Loss	(111)	(1,682)
Components of the net periodic benefit cost
Service cost	153	155	142
Interest cost	396	476	422
Expected return on plan assets	(433)	(539)	(402)
Amortization of net actuarial loss	54	9	9
Amortization of prior service cost (credit)	0	0	0
Foreign currency	(35)	(61)	21
Curtailment charge	0	0	0
Settlement credit	0	0	0
Net periodic benefit cost	135	40	192
Changes in accumulated other comprehensive income:
Net actuarial loss (gain)	(1,517)	987	467
Amortization of prior service (cost) credit	0	0	0
Amortization of net actuarial loss	(54)	(9)	(9)
Total recognized in other comprehensive (income) loss	(1,571)	978	458
Total recognized in net periodic benefit (cost) and other comprehensive (income) loss	(1,436)	1,018	$ 650
Expected future benefit payments
2016	225
2017	230
2018	238
2019	244
2020	251
2021 to 2025	1,377
Total	2,565
U.K. Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans
Expected future employer contributions in the next fiscal year	308
Accumulated benefit obligations
Accumulated benefit obligations	9,720	10,658
German Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans
Expected future employer contributions in the next fiscal year	33
Accumulated benefit obligations
Accumulated benefit obligations	870	$ 1,027
Postretirement Medical Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans
Expected future employer contributions in the next fiscal year	$ 835
Weighted-average assumptions used to determine benefit obligation
Discount rate	3.70%	3.39%
Rate of compensation increase	0.00%	0.00%
Weighted-average assumptions used to determine net periodic benefit costs
Discount rate	3.39%	4.10%	3.27%
Expected long-term rate of return on plan assets	0.00%	0.00%	0.00%
Rate of compensation increase	0.00%	0.00%	0.00%
Assumed healthcare cost trend rates
Healthcare cost trend rate assumption for the next year	6.76%	7.50%
Rate to which the cost trend rate is assumed to decline (the ultimate trend rate)	5.00%	5.00%
Year that the rate reaches the ultimate trend rate	2031	2031
Effect of one-percentage-point change in assumed healthcare cost trends
Effect of one-percentage-point decrease on total of service and interest cost components	$ (37)
Effect of one-percentage-point increase on total of service and interest cost components	42
Effect of one-percentage-point decrease on postretirement benefit obligation	(803)
Effect of one-percentage-point increase on postretirement benefit obligation	910
Change in benefit obligation:
Benefit obligation at beginning of year	13,292	$ 13,186
Service cost	96	128	$ 154
Interest cost	393	497	443
Plan participants' contributions	0	0
Actuarial (gain) loss	(1,618)	591
Foreign currency	0	0
Benefits paid	(1,019)	(1,110)
Settlement	0	0
Benefit obligation at end of year	11,144	13,292	13,186
Change in fair value of plan assets and net accrued liabilities:
Fair value of plan assets at beginning of year	0	0
Actual return on plan assets	0	0
Employer contributions	1,019	1,110
Plan participants' contributions	0	0
Foreign exchange	0	0
Benefits paid	(1,019)	(1,110)
Settlement	0	0
Fair value of plan assets at end of year	0	0	0
Funded status at end of year	(11,144)	(13,292)
Amounts recognized in the Consolidated Balance Sheets consist of:
Noncurrent Other Assets	0	0
Current Liabilities	(835)	(947)
Long-Term Liabilities	(10,309)	(12,345)
Net accrued asset (liability)	(11,144)	(13,292)
Amounts recognized in Accumulated Other Comprehensive Loss consist of:
Prior service (cost) credit	0	0
Net actuarial loss	(560)	(2,178)
Accumulated Other Comprehensive Loss	(560)	(2,178)
Components of the net periodic benefit cost
Service cost	96	128	154
Interest cost	393	497	443
Expected return on plan assets	0	0	0
Amortization of net actuarial loss	0	0	201
Amortization of prior service cost (credit)	0	(6)	(103)
Foreign currency	0	0	0
Curtailment charge	0	0	0
Settlement credit	0	0	0
Net periodic benefit cost	489	619	695
Changes in accumulated other comprehensive income:
Net actuarial loss (gain)	(1,618)	591	(1,001)
Amortization of prior service (cost) credit	0	6	103
Amortization of net actuarial loss	0	0	(201)
Total recognized in other comprehensive (income) loss	(1,618)	597	(1,099)
Total recognized in net periodic benefit (cost) and other comprehensive (income) loss	(1,129)	$ 1,216	$ (404)
Expected future benefit payments
2016	835
2017	890
2018	914
2019	959
2020	1,010
2021 to 2025	4,574
Total	9,182
Amounts that will be amortized from accumulated other comprehensive income (loss) in next fiscal year
Net actuarial loss	173
Prior service cost	$ 0