Reportable Segments - Segment Income (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Segment Reporting Information
Sales to external customers	$ 322.0	$ 289.5	$ 610.5	$ 591.4
Depreciation and amortization expense	19.8	23.3	39.3	46.9
Operating income (loss)	25.6	25.8	54.5	41.6
Restructuring costs	0.3	5.6	1.0	10.8
Increase in fair value of contingent consideration liabilities			2.0
Operating Segments | Cryo Tank Solutions
Segment Reporting Information
Sales to external customers	97.8	105.3	201.7	203.3
Depreciation and amortization expense	3.8	4.6	7.7	9.0
Operating income (loss)	13.4	15.9	29.0	27.5
Restructuring costs	0.0	1.1	0.3	2.9
Operating Segments | Heat Transfer Systems
Segment Reporting Information
Sales to external customers	65.2	97.3	134.4	210.2
Depreciation and amortization expense	9.5	14.2	19.0	28.3
Operating income (loss)	(0.5)	7.2	3.4	12.7
Restructuring costs	0.3	2.9	0.7	5.7
Operating Segments | Specialty Products
Segment Reporting Information
Sales to external customers	106.8	48.6	184.1	101.5
Depreciation and amortization expense	3.4	1.0	6.5	2.4
Operating income (loss)	23.4	11.7	41.3	25.5
Restructuring costs	0.0	0.0	0.0	0.0
Increase in fair value of contingent consideration liabilities	1.2		2.0
Operating Segments | Repair, Service & Leasing
Segment Reporting Information
Sales to external customers	54.6	40.1	96.0	80.8
Depreciation and amortization expense	2.7	3.0	5.3	6.3
Operating income (loss)	5.6	7.6	13.9	12.2
Restructuring costs	0.0	0.0	0.0	0.0
Intersegment Eliminations
Segment Reporting Information
Sales to external customers	(2.4)	(1.8)	(5.7)	(4.4)
Depreciation and amortization expense	0.0	0.0	0.0	0.0
Operating income (loss)	0.0	0.0	0.0	0.0
Corporate
Segment Reporting Information
Sales to external customers	0.0	0.0	0.0	0.0
Depreciation and amortization expense	0.4	0.5	0.8	0.9
Operating income (loss)	(16.3)	(16.6)	(33.1)	(36.3)
Restructuring costs	$ 0.0	$ 1.6	$ 0.0	$ 2.2