Comprehensive Income Total Other Comprehensive Income (Loss) (Details) (USD $)	12 Months Ended			1 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009	Aug. 31, 2010 Interest Rate Swap [Member]	Jul. 31, 2010 Interest Rate Swap [Member]
Other Comprehensive Income (Loss), before Tax [Abstract]
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, before Tax	$ 615,000	$ 1,265,000	$ 2,213,000
Other Comprehensive Income (Loss), Amortization, Pension and Other Postretirement Benefit Plans, Net Prior Service Cost (Credit) Recognized in Net Periodic Benefit Cost, before Tax			230,000
Other Comprehensive Income Derivatives Settlement Of Forward Starting Interest Rate Swap Agreement Before Tax		(8,663,000)
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, before Tax	862,000	332,000
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Net Unamortized Gain (Loss) Arising During Period, before Tax	(1,735,000)	(734,000)	263,000
Other Comprehensive Income (Loss), Finalization of Pension and Non-Pension Postretirement Plan Valuation, before Tax			2,051,000
Other Comprehensive Income (Loss), before Tax	(258,000)	(7,800,000)	4,757,000
Other Comprehensive Income (Loss), Tax [Abstract]
Other Comprehensive Income (Loss), Foreign Currency Translation Gain (Loss) Arising During Period, Tax	0	0	0
Other Comprehensive Income (Loss), Amortization, Pension and Other Postretirement Benefit Plans, Net Prior Service Cost Recognized in Net Periodic Pension Cost, Tax Effect			(86,000)
Other Comprehensive Income Derivatives Settlement Of Forward Starting Interest Rate Swap Agreement Tax Effect		0
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Tax Effect	0	0
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Net Unamortized Gain (Loss) Arising During Period, Tax	649,000	275,000	(98,000)
Other Comprehensive Income (Loss), Finalization of Pension and Non-Pension Postretirement Plan Valuation, Tax			(768,000)
Other Comprehensive Income (Loss), Tax	649,000	275,000	(952,000)
Other Comprehensive Income (Loss), Net of Tax
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Gain (Loss) Arising During Period, Net of Tax	615,000	1,265,000	2,213,000
Other Comprehensive Income (Loss), Amortization, Pension and Other Postretirement Benefit Plans, Net Prior Service Cost Recognized in Net Periodic Pension Cost, Net of Tax			144,000
Other Comprehensive Income Derivatives Settlement Of Forward Starting Interest Rate Swap Agreement Net of Tax		(8,663,000)
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax	862,000	332,000
Other Comprehensive Income (Loss), Reclassification, Pension and Other Postretirement Benefit Plans, Net (Gain) Loss Recognized in Net Periodic Benefit Cost, Net of Tax	(1,086,000)	(459,000)	165,000
Other Comprehensive Income (Loss), Finalization of Pension and Non-Pension Postretirement Plan Valuation, Net of Tax			1,283,000
Other comprehensive income (loss), net of tax	391,000	(7,525,000)	3,805,000
Debt Instrument, Face Amount					250,000,000
Debt Instrumentm Fixed Rate Debt Term Of Debt					10 years
Settlement of forward starting interest rate swap agreement	0	(8,663,000)	0	(8,700,000)
Interest expense	$ 12,939,000	$ 6,680,000	$ 4,414,000	$ 100,000