Pensions And Other Postretirement Benefits (Schedule Of Defined Benefit Pension Plans And Other Postretirement Benefits Plan) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at December 31	$ 357,967	$ 377,607
Noncurrent assets	58,075	121,631
Noncurrent liabilities	(124,310)	(126,479)
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	8,674	7,702	7,229
Interest cost	19,531	18,615	18,477
Actuarial losses (gains)	793	537	245
Termination benefits		(926)	(6,411)
Funded status at December 31	(36,302)	27,851
Unrecognized transition losses	24	42
Unrecognized prior service cost	808	923
Unrecognized net actuarial losses	158,425	82,903
Net amount recognized	122,955	111,719
Noncurrent assets	58,075	121,631
Current liabilities	(4,722)	(4,779)
Noncurrent liabilities	(89,655)	(89,001)
Net amount recognized	(36,302)	27,851
Net actuarial losses	158,425	82,903
Prior service cost (credit)	808	923
Unrecognized net initial obligation	24	42
Total (before tax effects)	159,257	83,868
Accumulated Benefit Obligations for all Defined Benefit Plans	347,636	332,544
Other Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	785	763	719
Interest cost	1,501	1,730	1,836
Actuarial losses (gains)	(455)	(555)	(401)
Termination benefits			(250)
Funded status at December 31	(30,425)	(32,734)
Unrecognized transition losses
Unrecognized prior service cost	(3,072)	(3,527)
Unrecognized net actuarial losses	12,212	15,202
Net amount recognized	(21,285)	(21,059)
Noncurrent assets
Current liabilities	(2,096)	(2,538)
Noncurrent liabilities	(28,329)	(30,196)
Net amount recognized	(30,425)	(32,734)
Net actuarial losses	12,212	15,202
Prior service cost (credit)	(3,072)	(3,527)
Unrecognized net initial obligation
Total (before tax effects)	9,140	11,675
Accumulated Benefit Obligations for all Defined Benefit Plans
Plan Assets [Member] | Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Participant contributions	153	137
Benefits paid	(16,308)	(14,659)
Transfers
Currency translation	(694)	342
Fair value of plan assets at January 1	377,607	342,874
Actual return on plan assets	(4,428)	48,001
Employer contributions	4,259	3,501
Reimbursement of German benefits	(2,622)	(2,589)
Fair value of plan assets at December 31	357,967	377,607
Plan Assets [Member] | Other Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Participant contributions	245	234
Benefits paid	(2,559)	(2,017)
Transfers
Currency translation
Fair value of plan assets at January 1
Actual return on plan assets
Employer contributions	2,314	1,783
Reimbursement of German benefits
Fair value of plan assets at December 31
Benefit Obligations [Member] | Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Benefit obligations at January 1	349,755	330,757
Service cost	8,674	7,702
Interest cost	19,531	18,615
Participant contributions	153	137
Actuarial losses (gains)	37,973	14,441
Benefits paid	(18,931)	(17,249)
Curtailments	(54)	(1,057)
Termination benefits		926
Currency translation	(2,832)	(4,517)
Benefit obligations at December 31	394,269	349,755
Benefit Obligations [Member] | Other Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Benefit obligations at January 1	32,734	30,014
Service cost	785	763
Interest cost	1,501	1,729
Participant contributions
Actuarial losses (gains)	(2,281)	2,011
Benefits paid	(2,314)	(1,783)
Curtailments
Termination benefits
Currency translation
Benefit obligations at December 31	$ 30,425	$ 32,734