Commitments And Contingencies (Schedule Of Activity Related To Asbestos Claim) (Detail) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2017 USD ($) LegalMatter	Mar. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Apr. 22, 2016 USD ($)	Sep. 30, 2014 USD ($)	Jun. 16, 2014 USD ($)
Loss Contingencies [Line Items]
Airplane Operating Lease Period Years				five
Fair Value Of Residual Value Guarantee	$ 2.5
Fair Value Of Residual Value Guarantee, Fair Value of Operating Lease Asset Threshold						$ 9.5
Asbestos Commitments and Contingencies
Loss Contingencies [Line Items]
Beginning claims	36,052	41,090	41,090
New claims	818	980	2,826
Settlements	(301)	(394)	(924)
Dismissals	(1,009)	(1,027)	(6,940)
Ending claims	35,560	40,649	41,090	41,090
New York | Asbestos Commitments and Contingencies
Loss Contingencies [Line Items]
Ending claims | LegalMatter	18,300
Texas | Asbestos Commitments and Contingencies
Loss Contingencies [Line Items]
Ending claims | LegalMatter	800
Mississippi | Asbestos Commitments and Contingencies
Loss Contingencies [Line Items]
Ending claims | LegalMatter	4,700
OHIO | Asbestos Commitments and Contingencies
Loss Contingencies [Line Items]
Ending claims | LegalMatter	200
George Coulbourn [Member] | Asbestos Commitments and Contingencies
Loss Contingencies [Line Items]
Court Judgment					$ 6.8
Ivan Sweberg [Member] | Asbestos Commitments and Contingencies
Loss Contingencies [Line Items]
Court Judgment							$ 5.3
Court_Reduced_Verdict							10.0
Paid Judgment Pursuant to Appeal	$ 2.7
Selwyn Hackshaw [Member] | Asbestos Commitments and Contingencies
Loss Contingencies [Line Items]
Court Judgment							3.1
Court_Reduced_Verdict							$ 6.0