Pensions and Other Postretirement Benefit Plans (Reconciliation of Level 3 Assets) (Details) (Pension Plans [Member], USD $) In Thousands, unless otherwise specified				12 Months Ended				12 Months Ended				12 Months Ended				12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2011 Significant Unobservable Inputs (Level 3) [Member]	Dec. 31, 2010 Significant Unobservable Inputs (Level 3) [Member]	Dec. 31, 2011 Insurance Contracts [Member]	Dec. 31, 2010 Insurance Contracts [Member]	Dec. 31, 2011 Insurance Contracts [Member] Significant Unobservable Inputs (Level 3) [Member]	Dec. 31, 2010 Insurance Contracts [Member] Significant Unobservable Inputs (Level 3) [Member]	Dec. 31, 2011 Limited Partnerships [Member]	Dec. 31, 2010 Limited Partnerships [Member]	Dec. 31, 2011 Limited Partnerships [Member] Significant Unobservable Inputs (Level 3) [Member]	Dec. 31, 2010 Limited Partnerships [Member] Significant Unobservable Inputs (Level 3) [Member]	Dec. 31, 2011 Hedge Funds [Member]	Dec. 31, 2010 Hedge Funds [Member]	Dec. 31, 2011 Hedge Funds [Member] Significant Unobservable Inputs (Level 3) [Member]	Dec. 31, 2010 Hedge Funds [Member] Significant Unobservable Inputs (Level 3) [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, beginning of year	$ 304,658	$ 262,376	$ 247,072	$ 21,864	$ 30,209	$ 2,361	$ 2,050	$ 2,050	$ 1,549	$ 8,676	$ 9,115	$ 9,115	$ 9,066	$ 557	$ 10,699	$ 10,699	$ 19,594
Net realized (losses)/ gains				88	1,167				(25)			107	(2)			(19)	1,194
Net unrealized gains				414	2,378			311	203			235	1,247			(132)	928
Net purchases, issuances and settlements				0	426				426
Net transfers (out of) Level 3				(10,772)	(12,316)				(103)			(781)	(1,196)			(9,991)	(11,017)
Fair value of plan assets, end of year	$ 304,658	$ 262,376	$ 247,072	$ 11,594	$ 21,864	$ 2,361	$ 2,050	$ 2,361	$ 2,050	$ 8,676	$ 9,115	$ 8,676	$ 9,115	$ 557	$ 10,699	$ 557	$ 10,699