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Property, Plant and Equipment - Additional Information (Detail) - USD ($)
$ in Thousands
Jul. 01, 2017
Dec. 31, 2016
Property, Plant and Equipment [Line Items]    
Accumulated depreciation $ 8,460,000 $ 8,160,000
Property, plant and equipment, net 5,062,423 5,078,650
Group Of Wells Assets With Carrying Value Closest To Its Undiscounted Cash Flows [Member]    
Property, Plant and Equipment [Line Items]    
Property, plant and equipment, net $ 75,800 $ 80,800