Revenue - Disaggregation of Revenue (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2018
Disaggregation of Revenue
Revenues	$ 319.9	$ 599.6
Point in time
Disaggregation of Revenue
Revenues	217.8	416.2
Over time
Disaggregation of Revenue
Revenues	102.1	183.4
Natural gas processing (including petrochemical) applications
Disaggregation of Revenue
Revenues	69.0	127.7
Liquefied natural gas (LNG) applications
Disaggregation of Revenue
Revenues	42.6	84.8
Industrial gas applications
Disaggregation of Revenue
Revenues	3.0	6.4
HVAC, power and refining applications
Disaggregation of Revenue
Revenues	21.7	40.5
Bulk industrial gas applications
Disaggregation of Revenue
Revenues	64.9	117.9
Packaged gas industrial applications
Disaggregation of Revenue
Revenues	56.7	105.6
Respiratory therapy
Disaggregation of Revenue
Revenues	34.3	63.2
Cryobiological storage
Disaggregation of Revenue
Revenues	20.0	39.1
On-site generation systems
Disaggregation of Revenue
Revenues	7.7	14.4
Operating Segments | Energy & Chemicals
Disaggregation of Revenue
Revenues	100.8	190.7
Operating Segments | Energy & Chemicals | Point in time
Disaggregation of Revenue
Revenues	23.7	47.6
Operating Segments | Energy & Chemicals | Over time
Disaggregation of Revenue
Revenues	77.1	143.1
Operating Segments | Energy & Chemicals | Natural gas processing (including petrochemical) applications
Disaggregation of Revenue
Revenues	69.0	127.7
Operating Segments | Energy & Chemicals | Liquefied natural gas (LNG) applications
Disaggregation of Revenue
Revenues	7.1	16.1
Operating Segments | Energy & Chemicals | Industrial gas applications
Disaggregation of Revenue
Revenues	3.0	6.4
Operating Segments | Energy & Chemicals | HVAC, power and refining applications
Disaggregation of Revenue
Revenues	21.7	40.5
Operating Segments | Energy & Chemicals | Bulk industrial gas applications
Disaggregation of Revenue
Revenues	0.0	0.0
Operating Segments | Energy & Chemicals | Packaged gas industrial applications
Disaggregation of Revenue
Revenues	0.0	0.0
Operating Segments | Energy & Chemicals | Respiratory therapy
Disaggregation of Revenue
Revenues	0.0	0.0
Operating Segments | Energy & Chemicals | Cryobiological storage
Disaggregation of Revenue
Revenues	0.0	0.0
Operating Segments | Energy & Chemicals | On-site generation systems
Disaggregation of Revenue
Revenues	0.0	0.0
Operating Segments | Distribution & Storage
Disaggregation of Revenue
Revenues	157.4	293.5
Operating Segments | Distribution & Storage | Point in time
Disaggregation of Revenue
Revenues	134.7	255.8
Operating Segments | Distribution & Storage | Over time
Disaggregation of Revenue
Revenues	22.7	37.7
Operating Segments | Distribution & Storage | Natural gas processing (including petrochemical) applications
Disaggregation of Revenue
Revenues	0.0	0.0
Operating Segments | Distribution & Storage | Liquefied natural gas (LNG) applications
Disaggregation of Revenue
Revenues	35.8	70.0
Operating Segments | Distribution & Storage | Industrial gas applications
Disaggregation of Revenue
Revenues	0.0	0.0
Operating Segments | Distribution & Storage | HVAC, power and refining applications
Disaggregation of Revenue
Revenues	0.0	0.0
Operating Segments | Distribution & Storage | Bulk industrial gas applications
Disaggregation of Revenue
Revenues	64.9	117.9
Operating Segments | Distribution & Storage | Packaged gas industrial applications
Disaggregation of Revenue
Revenues	56.7	105.6
Operating Segments | Distribution & Storage | Respiratory therapy
Disaggregation of Revenue
Revenues	0.0	0.0
Operating Segments | Distribution & Storage | Cryobiological storage
Disaggregation of Revenue
Revenues	0.0	0.0
Operating Segments | Distribution & Storage | On-site generation systems
Disaggregation of Revenue
Revenues	0.0	0.0
Operating Segments | BioMedical
Disaggregation of Revenue
Revenues	62.0	116.7
Operating Segments | BioMedical | Point in time
Disaggregation of Revenue
Revenues	59.4	112.8
Operating Segments | BioMedical | Over time
Disaggregation of Revenue
Revenues	2.6	3.9
Operating Segments | BioMedical | Natural gas processing (including petrochemical) applications
Disaggregation of Revenue
Revenues	0.0	0.0
Operating Segments | BioMedical | Liquefied natural gas (LNG) applications
Disaggregation of Revenue
Revenues	0.0	0.0
Operating Segments | BioMedical | Industrial gas applications
Disaggregation of Revenue
Revenues	0.0	0.0
Operating Segments | BioMedical | HVAC, power and refining applications
Disaggregation of Revenue
Revenues	0.0	0.0
Operating Segments | BioMedical | Bulk industrial gas applications
Disaggregation of Revenue
Revenues	0.0	0.0
Operating Segments | BioMedical | Packaged gas industrial applications
Disaggregation of Revenue
Revenues	0.0	0.0
Operating Segments | BioMedical | Respiratory therapy
Disaggregation of Revenue
Revenues	34.3	63.2
Operating Segments | BioMedical | Cryobiological storage
Disaggregation of Revenue
Revenues	20.0	39.1
Operating Segments | BioMedical | On-site generation systems
Disaggregation of Revenue
Revenues	7.7	14.4
Intersegment eliminations
Disaggregation of Revenue
Revenues	(0.3)	(1.3)
Intersegment eliminations | Point in time
Disaggregation of Revenue
Revenues	0.0	0.0
Intersegment eliminations | Over time
Disaggregation of Revenue
Revenues	(0.3)	(1.3)
Intersegment eliminations | Natural gas processing (including petrochemical) applications
Disaggregation of Revenue
Revenues	0.0	0.0
Intersegment eliminations | Liquefied natural gas (LNG) applications
Disaggregation of Revenue
Revenues	(0.3)	(1.3)
Intersegment eliminations | Industrial gas applications
Disaggregation of Revenue
Revenues	0.0	0.0
Intersegment eliminations | HVAC, power and refining applications
Disaggregation of Revenue
Revenues	0.0	0.0
Intersegment eliminations | Bulk industrial gas applications
Disaggregation of Revenue
Revenues	0.0	0.0
Intersegment eliminations | Packaged gas industrial applications
Disaggregation of Revenue
Revenues	0.0	0.0
Intersegment eliminations | Respiratory therapy
Disaggregation of Revenue
Revenues	0.0	0.0
Intersegment eliminations | Cryobiological storage
Disaggregation of Revenue
Revenues	0.0	0.0
Intersegment eliminations | On-site generation systems
Disaggregation of Revenue
Revenues	$ 0.0	$ 0.0