Commitments And Contingencies (Schedule Of Activity Related To Asbestos Claim) (Detail) (Asbestos Commitments and Contingencies)	3 Months Ended				12 Months Ended
	Mar. 31, 2013		Mar. 31, 2012		Dec. 31, 2012		Mar. 31, 2013 Maritime Claims Claim	Dec. 30, 2009 Maritime Claims Claim
Loss Contingencies [Line Items]
Beginning claims	56,442		58,658		58,658
New claims	792		893		3,542
Settlements	(237)		(289)		(1,030)
Dismissals	(789)		(2,042)		(4,919)
Number Of Activated Maritime Claims	0	[1]	178	[1]	191	[1]
MARDOC claims							3,391
Number_Restored_Dismissed_Maritime_Claims							457
Net_Number_Restored_Maritime_Claims							2,934
Ending claims	56,208		57,398		56,442
Claims permanently dismissed							26,562
Remaining Claims							6,503
Total number of maritime claims								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 classified as active claims. In addition, the Company was named in 8 new maritime actions in 2010 (also not classified as active claims). Through March 31, 2013, pursuant to an ongoing review process initiated by the Court, 26,562 claims were permanently dismissed, and 3,391 claims were classified as active, of which 457 claims were subsequently dismissed, and 2,934 claims remain active (and have been added to "Ending claims"). The Company expects that more of the remaining 6,503 maritime actions will be activated, or permanently dismissed, as the Court's review process continues. The number on this line reflects the number of previously inactive MARDOC claims that were newly activated in a given period