Commitments and Contingencies (Asbestos Liability) (Detail)	3 Months Ended					9 Months Ended		12 Months Ended
	Sep. 30, 2019 USD ($) claim agreement	Sep. 30, 2018 USD ($)	Jun. 30, 2017 USD ($)	Mar. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Sep. 30, 2019 USD ($) claim agreement	Sep. 30, 2018 USD ($)	Dec. 31, 2018 USD ($) claim	Dec. 31, 2017 USD ($) claim	Dec. 31, 2016 USD ($)	Mar. 31, 2019 claim	Jun. 30, 2018 claim	Mar. 31, 2018 claim	Oct. 06, 2016 USD ($)	Apr. 22, 2016 USD ($)	Feb. 09, 2016 USD ($)	Jul. 02, 2015 USD ($)	Jun. 16, 2014 USD ($)	Sep. 17, 2013 USD ($)	Mar. 01, 2013 USD ($)	Feb. 25, 2013 USD ($)	Feb. 23, 2011 USD ($)	Mar. 23, 2010 USD ($)
Loss Contingencies [Line Items]
Payments for asbestos-related fees and costs, net of insurance recoveries						$ 29,000,000.0	$ 46,400,000
Current portion of total estimated liability	$ 66,000,000.0					$ 66,000,000.0		$ 66,000,000.0
Asbestos Commitments and Contingencies
Loss Contingencies [Line Items]
Pending claims | claim	28,829					28,829		29,089	32,234		28,851	29,323	29,920
Payments for asbestos-related fees and costs, net of insurance recoveries	$ 11,000,000.0	$ 11,600,000				$ 28,900,000	46,400,000	$ 63,900,000
Cumulative claims resolved | claim	138,000					138,000
Settlement cost	$ 640,000,000					$ 640,000,000
Average settlement cost per resolved claim								11,300	$ 7,800	$ 3,900
Cumulative average settlement cost per resolved claim	4,600					4,600
Estimated payments to current and future claimants								36,000,000,000
Additional liability					$ 227,000,000
Liability for claims	474,000,000				$ 696,000,000	474,000,000				$ 696,000,000
Percentage Of Asbestos Liability Attributable To Settlement And Denfese Costs For Future Claims					80.00%					80.00%
Current portion of total estimated liability	$ 66,000,000					$ 66,000,000
Number of buyout agreements with excess insurer groups | agreement	10					10
Aggregate value of policy buyout agreements	$ 82,500,000					$ 82,500,000
Estimated Percentage Of Insurance Which Covers Asbestos Costs					21.00%					21.00%
Insurance reimbursement asset	77,000,000				$ 143,000,000	77,000,000				$ 143,000,000
Gross Settlement And Defense Incurred Costs	$ 13,900,000	$ 13,800,000				$ 54,200,000	$ 69,700,000	$ 88,800,000
Mesothelioma Claims Percentage Pending Asbestos Claims					10.00%					10.00%
Mesothelioma Claims Percentage Aggregate Settlement Defense Costs					90.00%					90.00%
Thomas Amato | Asbestos Commitments and Contingencies
Loss Contingencies [Line Items]
Jury Verdict																					$ 2,500,000
PaidJuryVerdict			$ 300,000
Share Of Responsibility Of Verdict																					10.00%
James Nelson | Asbestos Commitments and Contingencies
Loss Contingencies [Line Items]
Jury Verdict																							$ 14,500,000
Share Of Responsibility Of Verdict																							9.09%
Court judgment against all parties held responsible																						$ 4,000,000.0
Additional interest on the compensation awarded																						$ 10,000.00
Larry Bell | Asbestos Commitments and Contingencies
Loss Contingencies [Line Items]
Share Of Responsibility Of Verdict																							5.00%
Frank Vincinguerra | Asbestos Commitments and Contingencies
Loss Contingencies [Line Items]
Jury Verdict																					$ 2,300,000
PaidJuryVerdict					$ 600,000
Share Of Responsibility Of Verdict																					20.00%
Ivo Peraica | Asbestos Commitments and Contingencies
Loss Contingencies [Line Items]
Court Judgment																				$ 10,600,000
Reduced Damages														$ 4,250,000
CourtJudgmentIncludingSetoffs														1,940,000
Paid Judgment Pursuant to Appeal				$ 2,700,000
Jury Verdict Total																				35,000,000
Court_Reduced_Verdict																				$ 18,000,000
Richard DeLisle | Asbestos Commitments and Contingencies
Loss Contingencies [Line Items]
Court Judgment																			$ 1,300,000
Jury Verdict																			$ 8,000,000
Share Of Responsibility Of Verdict																			16.00%
Ivan Sweberg | Asbestos Commitments and Contingencies
Loss Contingencies [Line Items]
Court Judgment																		$ 5,300,000
Reduced Damages														9,500,000
CourtJudgmentIncludingSetoffs														4,730,000
Paid Judgment Pursuant to Appeal				$ 5,700,000
Jury Verdict Total																		15,000,000
Court_Reduced_Verdict																		10,000,000
Selwyn Hackshaw | Asbestos Commitments and Contingencies
Loss Contingencies [Line Items]
Court Judgment																		3,100,000
Reduced Damages														3,000,000
CourtJudgmentIncludingSetoffs														$ 0
Jury Verdict Total																		10,000,000
Court_Reduced_Verdict																		$ 6,000,000
James Poage | Asbestos Commitments and Contingencies
Loss Contingencies [Line Items]
Compensatory Damages																	$ 1,500,000
Additional Damages																	10,000,000
Court Judgment																	$ 10,800,000
Valent Rabovsky | Asbestos Commitments and Contingencies
Loss Contingencies [Line Items]
Court Judgment															$ 400,000
Jury Verdict Total																$ 1,085,000.000
Share Of Responsibility Of Verdict																30.00%
George Coulbourn | Asbestos Commitments and Contingencies
Loss Contingencies [Line Items]
Additional Damages															5,000,000
Court Judgment															6,800,000
Jury Verdict Total															$ 9,000,000
Share Of Responsibility Of Verdict															20.00%
Geoffrey_Anisansel | Asbestos Commitments and Contingencies
Loss Contingencies [Line Items]
Jury Verdict Total			$ 20,000,000
New York | Asbestos Commitments and Contingencies
Loss Contingencies [Line Items]
Pending claims | claim	18,000					18,000
Mississippi | Asbestos Commitments and Contingencies
Loss Contingencies [Line Items]
Pending claims | claim	300					300
Texas | Asbestos Commitments and Contingencies
Loss Contingencies [Line Items]
Pending claims | claim	100					100
Ohio | Asbestos Commitments and Contingencies
Loss Contingencies [Line Items]
Pending claims | claim	200					200