Commitments And Contingencies (Schedule Of Activity Related To Asbestos Claims) (Details)	12 Months Ended	3 Months Ended				12 Months Ended
	Dec. 31, 2010	Mar. 31, 2012 Asbestos Commitments And Contingencies [Member]		Mar. 31, 2011 Asbestos Commitments And Contingencies [Member]		Dec. 31, 2011 Asbestos Commitments And Contingencies [Member]		Mar. 31, 2012 Asbestos Commitments And Contingencies [Member] Maritime Claims [Member]
Loss Contingencies [Line Items]
Beginning claims		58,658		64,839		64,839
New claims		893		965		3,748
Settlements		(289)		(340)		(1,117)
Dismissals		(2,042)		(817)		(11,059)
MARDOC claims		178	[1]	(1)	[1]	2,247	[1]	3,378
Ending claims		57,398		64,646		58,658
Claims permanently dismissed								26,574
Remaining claims								6,504
Total number of maritime claims								36,448
New filings added to active status, number	8

[1] As of January 1, 2010, the Company was named in 36,448 maritime actions which had been administratively dismissed by the United States District Court for the Eastern District of Pennsylvania ("MARDOC claims"), and therefore were not included in "Beginning claims". As of March 31, 2012, pursuant to an ongoing review process initiated by the Court, 26,574 claims were permanently dismissed, and 3,378 claims remain active (and have been added to "Ending claims"). In addition, the Company was named in 8 new maritime actions in 2010 (not included in "Beginning claims"). The Company expects that more of the remaining 6,504 maritime actions will be activated, or permanently dismissed, as the Court's review process continues.