Segment Reporting (Tables)

3 Months Ended

Mar. 31, 2020

Segment Reporting [Abstract]

Summarized Financial Information for Reportable Segments

	Three Months Ended March 31,
	2020			2019
	(in thousands)
Revenues
Energy	$	152,373		$	236,075
Industrial		170,287			192,171
Total revenues		322,660			428,246
Segment contribution margin
Energy		21,538			22,019
Industrial		54,200			51,622
Total segment contribution margin		75,738			73,641
Operating costs of idled facilities and excess railcar capacity		6,952			6,955
Selling, general, and administrative		33,447			41,960
Depreciation, depletion, and amortization		34,830			58,095
Restructuring and other charges		5,499			2,002
Other operating income, net		(2,268	)		(6,859	)
Loss from operations		(2,722	)		(28,512	)
Interest expense, net		23,583			25,603
Other non-operating expense, net		2,912			2,187
Loss before benefit for income taxes	$	(29,217	)	$	(56,302	)