Pensions and Other Postretirement Benefits (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Change in plan assets [Roll forward]
Fair value of plan assets at beginning of year	$ 270,984
Fair value of plan assets at end of year	274,589	270,984
Amounts recognized in balance sheet associated with retirement benefit plans [Abstract]
Included in other assets	802	1,741
Accrued pension and other postretirement costs	(319,136)	(291,117)
Total actuarial items	172,361	131,177
Components of actuarial items [Abstract]
Total actuarial items	172,361	131,177
Other retirement obligations [Abstract]
Company's matching expense for 401(k) savings plans	4,985	5,399	5,004
Liabilities recorded for post-employment benefit obligations to certain terminated employees related to acquisitions	6,818	9,222
Accrued liabilities for post-employment benefit obligations to certain terminated employees related to acquisitions	1,823	2,126
Defined Benefit Pension [Member]
Defined benefit pension plans [Abstract]
Assets held in trust	5,445
Deferred compensation arrangement, annual retirement benefit to surviving spouse	614
Deferred Compensation [Member]
Defined benefit pension plans [Abstract]
Assets held in trust	11,830	10,663
Non-qualified Pension Plans [Member]
Defined benefit pension plans [Abstract]
Assets held in trust	14,423	14,922
U.S. Pension Plans [Member]
Change in benefit obligation [Roll forward]
Benefit obligation at beginning of year	303,613	289,430
Service cost (adjusted for actual employee contributions)	0	0	0
Interest cost	16,332	16,341	16,745
Plan amendments	0	8,777
Spin-off of VPG	0	(1,255)
Actuarial (gains) losses	20,320	7,379
Benefits paid	(17,738)	(17,059)
Benefit obligation at end of year	322,527	303,613	289,430
Change in plan assets [Roll forward]
Fair value of plan assets at beginning of year	238,523	216,641
Actual return on plan assets	1,117	26,116
Spin-off of VPG	0	0
Company contributions	17,143	12,825
Benefits paid	(17,738)	(17,059)
Fair value of plan assets at end of year	239,045	238,523	216,641
Funded status at end of year	(83,482)	(65,090)
Amounts recognized in balance sheet associated with retirement benefit plans [Abstract]
Accrued pension and other postretirement costs	83,482	65,090
Total actuarial items	135,009	108,239
Total	51,527	43,149
Components of actuarial items [Abstract]
Unrecognized net actuarial loss (gain)	130,608	101,236
Unamortized prior service (credit) cost	4,401	7,003
Total actuarial items	135,009	108,239
Projected and accumulated benefit obligations [Abstract]
Accumulated benefit obligation, all plans	322,527	303,613
Plans for which the accumulated benefit obligation exceeds plan assets [Abstract]
Projected benefit obligation	322,527	303,613	289,430
Accumulated benefit obligation	322,527	303,613
Fair value of plan assets	239,045	238,523
Components of net periodic pension cost [Abstract]
Net service cost	0	0	0
Interest cost	16,332	16,341	16,745
Expected return on plan assets	(19,082)	(18,098)	(14,955)
Amortization of actuarial losses	9,006	9,315	11,300
Amortization of prior service (credit) cost	2,361	1,477	34
Curtailment and settlement losses (gains)	148	0	0
Net periodic benefit cost	8,765	9,035	13,124
Weighted average assumptions used to calculate benefit obligations [Abstract]
Discount rate (in hundredths)	5.00%	5.50%
Rate of compensation increase (in hundredths)	0.00%	0.00%
Weighted average assumptions used calculating net periodic benefit cost [Abstract]
Discount rate (in hundredths)	5.50%	5.75%
Rate of compensation increase (in hundredths)	0.00%	0.00%
Expected return on plan assets (in hundredths)	8.00%	8.50%
Target allocation of assets in equity securities (in hundredths)	60.00%
Target allocation percentage of assets invested in fixed income securities (in hundredths)	40.00%
Actual plan asset allocations [Abstract]
Equity securities (in hundredths)	61.00%	63.00%
Fixed income securities (in hundredths)	39.00%	36.00%
Cash and cash equivalents (in hundredths)	0.00%	1.00%
Total (in hundredths)	100.00%	100.00%
Estimated future benefit payments [Abstract]
2012	18,121
2013	18,592
2014	25,359
2015	20,737
2016	21,096
2017-2021	106,408
Estimated future employer contributions to U.S. defined benefit pension plans in next fiscal year, minimum	12,000
Estimated future employer contributions to U.S. defined benefit pension plans in next fiscal year, maximum	16,000
Non-U.S. Pension Plans [Member]
Change in benefit obligation [Roll forward]
Benefit obligation at beginning of year	231,870	231,416
Service cost (adjusted for actual employee contributions)	3,197	3,027	2,991
Interest cost	10,366	10,774	11,174
Plan amendments	531	163
Spin-off of VPG	0	(13,882)
Actuarial (gains) losses	14,986	20,899
Benefits paid	(12,763)	(10,991)
Currency translation	(4,220)	(9,536)
Benefit obligation at end of year	243,966	231,870	231,416
Change in plan assets [Roll forward]
Fair value of plan assets at beginning of year	32,461	34,762
Actual return on plan assets	830	2,376
Spin-off of VPG	0	(8,939)
Company contributions	15,325	14,427
Benefits paid	(12,763)	(10,991)
Currency translation	(309)	826
Fair value of plan assets at end of year	35,544	32,461	34,762
Funded status at end of year	(208,422)	(199,409)
Amounts recognized in balance sheet associated with retirement benefit plans [Abstract]
Included in other assets	802	1,741
Accrued pension and other postretirement costs	209,224	201,150
Total actuarial items	41,494	28,454
Total	(166,928)	(170,955)
Components of actuarial items [Abstract]
Unrecognized net actuarial loss (gain)	41,494	28,454
Unamortized prior service (credit) cost	0	0
Total actuarial items	41,494	28,454
Projected and accumulated benefit obligations [Abstract]
Accumulated benefit obligation, all plans	225,381	213,893
Plans for which the accumulated benefit obligation exceeds plan assets [Abstract]
Projected benefit obligation	236,323	225,291
Accumulated benefit obligation	221,637	210,786
Fair value of plan assets	27,098	24,178
Components of net periodic pension cost [Abstract]
Net service cost	3,197	3,027	2,991
Interest cost	10,366	10,774	11,174
Expected return on plan assets	(1,651)	(1,629)	(1,689)
Amortization of actuarial losses	993	160	70
Amortization of prior service (credit) cost	531	163	94
Curtailment and settlement losses (gains)	0	0	405
Net periodic benefit cost	13,436	12,495	13,045
Weighted average assumptions used to calculate benefit obligations [Abstract]
Discount rate (in hundredths)	3.96%	4.50%
Rate of compensation increase (in hundredths)	2.31%	2.19%
Weighted average assumptions used calculating net periodic benefit cost [Abstract]
Discount rate (in hundredths)	4.50%	5.19%
Rate of compensation increase (in hundredths)	2.19%	2.34%
Expected return on plan assets (in hundredths)	4.26%	4.89%
Actual plan asset allocations [Abstract]
Equity securities (in hundredths)	19.00%	24.00%
Fixed income securities (in hundredths)	29.00%	26.00%
Cash and cash equivalents (in hundredths)	52.00%	50.00%
Total (in hundredths)	100.00%	100.00%
Estimated future benefit payments [Abstract]
2012	11,524
2013	12,984
2014	14,026
2015	12,950
2016	13,522
2017-2021	77,915
U.S. Postretirement Plans [Member]
Change in benefit obligation [Roll forward]
Benefit obligation at beginning of year	10,633	13,617
Service cost (adjusted for actual employee contributions)	77	95	113
Interest cost	547	640	810
Spin-off of VPG		(2,493)
Actuarial (gains) losses	675	(148)
Benefits paid	(1,008)	(1,078)
Benefit obligation at end of year	10,924	10,633	13,617
Change in plan assets [Roll forward]
Fair value of plan assets at beginning of year	0
Spin-off of VPG	0
Benefits paid	(1,008)	(1,078)
Fair value of plan assets at end of year	0	0
Funded status at end of year	(10,924)	(10,633)
Amounts recognized in balance sheet associated with retirement benefit plans [Abstract]
Accrued pension and other postretirement costs	10,924	10,633
Total actuarial items	(4,142)	(5,516)
Total	(15,066)	(16,149)
Components of actuarial items [Abstract]
Unrecognized net actuarial loss (gain)	(2,309)	(3,299)
Unamortized prior service (credit) cost	1,865	(2,296)
Unrecognized net transition obligation	32	79
Total actuarial items	(4,142)	(5,516)
Components of net periodic pension cost [Abstract]
Net service cost	77	95	113
Interest cost	547	640	810
Amortization of actuarial losses	(315)	(244)	(300)
Amortization of prior service (credit) cost	(431)	(434)	(441)
Amortization of transition obligation	47	61	74
Net periodic benefit cost	(75)	118	256
Weighted average assumptions used to calculate benefit obligations [Abstract]
Discount rate (in hundredths)	5.00%	5.50%
Rate of compensation increase (in hundredths)	0.00%	0.00%
Weighted average assumptions used calculating net periodic benefit cost [Abstract]
Discount rate (in hundredths)	5.50%	5.75%
Rate of compensation increase (in hundredths)	0.00%	0.00%
Estimated future benefit payments [Abstract]
2012	1,024
2013	1,018
2014	1,010
2015	1,012
2016	1,000
2017-2021	4,369
Non-U.S. Postretirement Plans [Member]
Change in benefit obligation [Roll forward]
Benefit obligation at beginning of year	5,801	5,841
Service cost (adjusted for actual employee contributions)	275	255	330
Interest cost	282	291	391
Actuarial (gains) losses	341	778
Benefits paid	(618)	(854)
Currency translation	(109)	(510)
Benefit obligation at end of year	5,972	5,801	5,841
Change in plan assets [Roll forward]
Fair value of plan assets at beginning of year	0
Benefits paid	(618)	(854)
Fair value of plan assets at end of year	0	0
Funded status at end of year	(5,972)	(5,801)
Amounts recognized in balance sheet associated with retirement benefit plans [Abstract]
Accrued pension and other postretirement costs	5,972	5,801
Total	(5,972)	(5,801)
Components of actuarial items [Abstract]
Unrecognized net actuarial loss (gain)	0	0
Unamortized prior service (credit) cost	0	0
Unrecognized net transition obligation	0	0
Components of net periodic pension cost [Abstract]
Net service cost	275	255	330
Interest cost	282	291	391
Amortization of actuarial losses	0	0	0
Amortization of prior service (credit) cost	0	0	0
Amortization of transition obligation	0	0	0
Net periodic benefit cost	557	546	721
Weighted average assumptions used to calculate benefit obligations [Abstract]
Discount rate (in hundredths)	5.09%	4.80%
Rate of compensation increase (in hundredths)	3.22%	3.00%
Weighted average assumptions used calculating net periodic benefit cost [Abstract]
Discount rate (in hundredths)	4.80%	5.50%
Rate of compensation increase (in hundredths)	3.00%	3.46%
Estimated future benefit payments [Abstract]
2012	581
2013	221
2014	331
2015	376
2016	509
2017-2021	3,090
Other Retirement Obligations [Member]
Amounts recognized in balance sheet associated with retirement benefit plans [Abstract]
Accrued pension and other postretirement costs	$ (9,534)	$ (8,443)