Property, Plant and Equipment - Schedule of Property, Plant and Equipment (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 16,754,603	$ 15,594,782
Less accumulated depreciation	(9,855,493)	(9,416,227)
Property, plant and equipment, net, total	6,899,110	6,178,555
Land and Improvements, Net [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	744,305	719,736
Buildings and Improvements [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	1,505,913	1,413,690
Machinery and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	12,204,738	11,630,179
Proved Oil and Gas Properties [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	558,231	558,123
Leasehold Interest in Unproved Oil and Gas Properties [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	138,000	165,000
Construction in Process and Equipment Deposits [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 1,603,416	$ 1,108,054