Discontinued Operations and Disposition - Summary of Assets and Liabilities of ASW (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Current assets of discontinued operations	$ 0	$ 20,238
Current liabilities of discontinued operations	$ 0	9,458
ASW Steel Inc [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Cash and cash equivalents		1,124
Receivables		6,928
Inventories		13,764
Other assets		1,708
Property, plant and equipment, net		11,714
Charge for impairment		(15,000)
Current assets of discontinued operations		20,238
Accounts payable		8,890
Accrued payrolls and employee benefits		178
Other current liabilities		390
Current liabilities of discontinued operations		$ 9,458