Commitments And Contingencies (Schedule Of Activity Related To Asbestos Claim) (Detail) (Asbestos Commitments and Contingencies)	3 Months Ended			6 Months Ended				12 Months Ended
	Jun. 30, 2012		Jun. 30, 2011	Jun. 30, 2012		Jun. 30, 2011		Dec. 31, 2011		Dec. 31, 2010
Loss Contingencies [Line Items]
Beginning claims	57,398		64,646	58,658		64,839		64,839
New claims	894		893	1,787		1,858		3,748
Settlements	(258)		(263)	(547)		(603)		(1,117)
Dismissals	(474)		(8,873)	(2,516)		(9,690)		(11,059)
MARDOC claims	(1)	[1]		177	[1]	(1)	[1]	2,247	[1]
Ending claims	57,559		56,403	57,559		56,403		58,658
New Filings Added To Active Status, number										8
Maritime Claims
Loss Contingencies [Line Items]
MARDOC claims				3,377
Claims permanently dismissed	26,575			26,575
Remaining Claims	6,504			6,504
Total number of maritime claims	36,448			36,448

[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 June 30, 2012, pursuant to an ongoing review process initiated by the Court, 26,575 claims were permanently dismissed, and 3,377 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.