Commitments, Contingencies and Legal Proceedings - Additional Information (Detail)			1 Months Ended	3 Months Ended		9 Months Ended
	Oct. 14, 2014 USD ($)	Sep. 25, 2014	Jan. 31, 2008	Dec. 31, 2015 USD ($)	Sep. 30, 2015 USD ($)	Sep. 30, 2015 USD ($) Operable_Unit	Sep. 30, 2014 USD ($)	May. 15, 2015	Dec. 31, 2014 USD ($)
Commitments Contingencies And Litigation [Line Items]
Number of operable units | Operable_Unit						5
Upper end estimate of total past and future response costs	$ 1,100,000,000
Uncertainty premium for future response costs	100,000,000
Cost of response incurred by government						$ 4,280,000
Initial minimum amount of NRD assessment						176,000,000
Initial maximum amount of NRD assessment						333,000,000
Revised minimum amount of NRD assessment						287,000,000
Revised maximum amount of NRD assessment						423,000,000
Cash payments towards completion of remediation activities	45,900,000					5,617,000	$ 39,000
Environmental loss contingencies	105,000,000
Other prepaid loss contingencies for earlier settlements	59,000,000
Increase in remediation activities reserve						10,000,000
Reserve for Environmental liabilities, current portion					$ 16,022,000	$ 16,022,000			$ 1,075,000
Maximum estimated percentage of discharge						27.00%
Whiting Litigation [Member]
Commitments Contingencies And Litigation [Line Items]
Remaining costs and damages amount						$ 33,000,000
2015 Work Plan [Member]
Commitments Contingencies And Litigation [Line Items]
Estimated cost of work to satisfy our share of obligation					10,000,000	10,000,000
2016 Work Plan [Member]
Commitments Contingencies And Litigation [Line Items]
Increase in remediation activities reserve					10,000,000
Scenario, Forecast [Member]
Commitments Contingencies And Litigation [Line Items]
Cash payments towards completion of remediation activities				$ 4,500,000
NCR [Member]
Commitments Contingencies And Litigation [Line Items]
Percentage of apportion liability on cost								28.00%
NCR and GP [Member] | Whiting Litigation [Member]
Commitments Contingencies And Litigation [Line Items]
Costs and damages amount						67,000,000
NCR and GP [Member] | 2016 Work Plan [Member] | Whiting Litigation [Member]
Commitments Contingencies And Litigation [Line Items]
Annual estimated cost rate seek by Government					100,000,000	$ 100,000,000
Minimum [Member]
Commitments Contingencies And Litigation [Line Items]
Period over which estimated cost to be incurred						2 years
Minimum [Member] | Appvion [Member]
Commitments Contingencies And Litigation [Line Items]
Litigation claim amount						$ 170,000,000
Maximum [Member]
Commitments Contingencies And Litigation [Line Items]
Estimated cost related to Fox River matter						$ 175,000,000
Period over which estimated cost to be incurred						3 years
OU2-5 [Member]
Commitments Contingencies And Litigation [Line Items]
Estimated future cost of work yet to be done	500,000,000
Annual estimated cost rate seek by Government					70,000,000	$ 70,000,000
NCR costs and damages percentage		100.00%
OU2-5 [Member] | Whiting Litigation [Member]
Commitments Contingencies And Litigation [Line Items]
NCR costs and damages percentage			100.00%
OU2-5 [Member] | 2015 Work Plan [Member]
Commitments Contingencies And Litigation [Line Items]
Annual remediation cost rate seek by Government					100,000,000	100,000,000
OU2-5 [Member] | Scenario, Forecast [Member]
Commitments Contingencies And Litigation [Line Items]
Estimated future cost of remediation				$ 10,000,000
Dredging Season [Member]
Commitments Contingencies And Litigation [Line Items]
Annual estimated cost rate seek by Government					$ 100,000,000	$ 100,000,000
OU1 [Member]
Commitments Contingencies And Litigation [Line Items]
Estimated future cost of work yet to be done	$ 100,000,000