Stockholder's Equity - Accumulated Other Comprehensive Income (Loss) - Changes in Accumulated Other Comprehensive Loss (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	$ (6,267)	$ (6,713)
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	895	3,021
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	(822)	68
Net current-period other comprehensive income (loss)	73	3,089
Ending balance	(6,194)	(3,739)
UnrealizedGainsLossesFromDefinedBenefitPensionAndPostretirementPlanItems [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(4,933)	(5,928)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	66	107
Net current-period other comprehensive income (loss)	66	107
Tax Cuts and Jobs Act, Reclassification from AOCI to Retained Earnings, Tax Effect
Ending balance	(4,867)	(5,821)
Accumulated (Gain) Loss from Commodity Contracts Cash Flows Hedges [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(1,334)	(785)
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	895	3,021
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	(888)	(39)
Net current-period other comprehensive income (loss)	7	2,982
Tax Cuts and Jobs Act, Reclassification from AOCI to Retained Earnings, Tax Effect		(115)
Ending balance	$ (1,327)	2,082
AOCI Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Prior Period Reclassification Adjustment		(115)
Tax Cuts and Jobs Act, Reclassification from AOCI to Retained Earnings, Tax Effect		$ (115)

Tax Cuts and Jobs Act, Reclassification from AOCI to Retained Earnings, Tax Effect

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Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

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Amount after tax, before reclassification adjustments of other comprehensive income (loss).

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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