Segment Information - Schedule of Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Segment Reporting Information [Line Items]
Revenue:	$ 330,007	$ 371,080	$ 973,344	$ 1,112,608
Income (loss) from continuing operations before interest expense and income taxes:	59,154	47,045	33,566	129,036
Interest expense	6,988	9,622	23,025	30,099
Income tax provision	14,783	13,705	10,034	31,505
Net income from continuing operations	37,383	23,718	507	67,432
Total	(3,194)	1,855	26,420	(408)
Depreciation and amortization	16,255	16,387	48,735	49,046
Diversified Industrial net sales
Segment Reporting Information [Line Items]
Revenue:	274,094	281,120	788,566	862,090
Income (loss) from continuing operations before interest expense and income taxes:	26,372	(3,042)	54,408	27,609
Depreciation and amortization	12,243	11,927	36,893	35,449
Energy net revenue
Segment Reporting Information [Line Items]
Revenue:	22,378	44,147	75,282	126,665
Income (loss) from continuing operations before interest expense and income taxes:	(1,891)	954	(7,041)	(472)
Depreciation and amortization	3,669	4,309	11,156	13,174
Financial Services revenue
Segment Reporting Information [Line Items]
Revenue:	33,535	45,813	109,496	123,853
Income (loss) from continuing operations before interest expense and income taxes:	28,701	20,436	31,892	48,012
Depreciation and amortization	304	110	567	309
Corporate and Other
Segment Reporting Information [Line Items]
Income (loss) from continuing operations before interest expense and income taxes:	5,972	28,697	(45,693)	53,887
Total	(3,194)	1,855	26,420	(408)
Depreciation and amortization	$ 39	$ 41	$ 119	$ 114