Other Operating Expenses and Income, Net - Additional Information (Detail) - Other Operating Income, Net - USD ($)	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018
Component Of Other Income And Expense [Line Items]
Restructuring charge	$ 7,113,000
Net gain on legal settlements			$ 7,677,000
Gain on sale of surplus land			$ 16,938,000
Repair costs related to leased railcars		$ 12,425,000

Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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