Commitments, Guarantees, Indemnifications, and Legal Proceedings - Additional Information (Details) - DeRidder, Louisiana - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2018	Feb. 08, 2017
Schedule Of Commitments And Contingencies [Line Items]
Loss contingency, period of occurrence	February 8, 2017
Liability insurance		$ 1.0
Property damages and business interruption insurance		$ 5.0
Claim with insurance carrier	$ 17.0
Insurance proceeds included in net cash provided by operating activities	14.5
Insurance proceeds included in net cash provided by investing activities	$ 2.5

Schedule of commitments and contingencies.

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- Definition

Amount of loss contingency liability.

+ References

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- Definition

The amount of insurance-related assessment liability that is expected to be recovered through policy surcharges applied to in-force policies.

+ References

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States when the existing condition, situation, or set of circumstances involving uncertainty occurred.

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Amount of receivable related to a loss contingency accrual. For example, an insurance recovery receivable.

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- Definition

Amount of cash inflow for proceeds from settlement of insurance claim, classified as investing activities. Excludes insurance settlement classified as operating activities.

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Amount of cash inflow for proceeds from settlement of insurance claim, classified as operating activities. Excludes insurance settlement classified as investing activities.

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