Goodwill and Other Intangible Assets, Net - Reconciliation (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2020	Dec. 31, 2019
Goodwill [Line Items]
Gross goodwill	$ 256,908	$ 254,594
Accumulated impairments	(104,968)	(104,968)
Net goodwill	151,940	149,626
Acquisitions	2,300
Currency translation adjustment	14
Diversified Industrial
Goodwill [Line Items]
Gross goodwill	183,169	180,855
Accumulated impairments	(40,178)	(40,178)
Net goodwill	142,991	140,677
Acquisitions	2,300
Currency translation adjustment	14
Energy net revenue
Goodwill [Line Items]
Gross goodwill	67,143	67,143
Accumulated impairments	(64,790)	(64,790)
Net goodwill	2,353	2,353
Acquisitions	0
Currency translation adjustment	0
Financial Services
Goodwill [Line Items]
Gross goodwill	6,515	6,515
Accumulated impairments	0	0
Net goodwill	6,515	6,515
Acquisitions	0
Currency translation adjustment	0
Corporate and Other
Goodwill [Line Items]
Gross goodwill	81	81
Accumulated impairments	0	0
Net goodwill	81	$ 81
Acquisitions	0
Currency translation adjustment	$ 0

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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