Commitments and Contingencies (Additional Information) (Detail)	12 Months Ended
	Dec. 31, 2015 USD ($) claims LegalMatter	Dec. 31, 2014 USD ($) claims	Dec. 31, 2013 USD ($) claims
Loss Contingencies [Line Items]
Number of pending claims | claims	488	440	362
Estimated total cleanup costs, accrual	$ 400,000
Number of claims dismissed | claims	231	104
Number of claims settled | claims	6	13
Claims settlements amount	$ 1,600,000	$ 3,200,000
Asbestos forecast claim period	10 years
Asbestos-related liabilities, estimated liability	$ 56,600,000	56,500,000
Asbestos-related liabilities, estimated insurance recovery	53,400,000	53,000,000
Environmental remediation expense (income)	$ 300,000	(800,000)	$ 500,000
Superfund Sites Proceedings
Loss Contingencies [Line Items]
Number of pending claims | LegalMatter	1
Estimated total cleanup costs, cost sharing percentage	2.00%
Loss contingency, minimum possible loss	$ 18,800,000
Loss contingency, maximum possible loss	29,600,000
PCB Contamination Proceedings
Loss Contingencies [Line Items]
PCB contamination of the building and pond, liability recording during the period	700,000
Remediation and monitoring costs incurred since inception related to the PCB soil and building contamination	2,500,000
PCB Contamination Proceedings | Building
Loss Contingencies [Line Items]
Remediation and monitoring costs incurred since inception related to the PCB soil and building contamination		$ 500,000
PCB Contamination Proceedings | Pond
Loss Contingencies [Line Items]
Estimated total cleanup costs, accrual	200,000
Connecticut Voluntary Corrective Action Program (VCAP)
Loss Contingencies [Line Items]
Estimated total cleanup costs, accrual	3,200,000
CT DEEP
Loss Contingencies [Line Items]
Estimated total cleanup costs, accrual	$ 0