XML 115 R96.htm IDEA: XBRL DOCUMENT v3.8.0.1
Impairment of goodwill - Narrative (Details)
$ in Millions
 12 Months Ended
Dec. 31, 2017
USD ($)
segment
cash_generating_unit
Dec. 31, 2017
Dec. 31, 2017
$ / €
Dec. 31, 2017
$ / £
Dec. 31, 2016
USD ($)
Dec. 31, 2015
USD ($)
Disclosure of impairment loss recognised or reversed [line items]            
Number of cash generating units | cash_generating_unit 6          
Number of reportable segments | segment 2          
Goodwill $ 59.6       $ 56.9 $ 62.2
Growth rate used to extrapolate cash flow projections   2.10%     2.10%  
Exchange rate applied to cash flow projections (in USD per GBP and EUR per USD)     1.19 1.35    
Minimum            
Disclosure of impairment loss recognised or reversed [line items]            
Discount rate applied to cash flow projections   8.50%     10.10%  
Maximum            
Disclosure of impairment loss recognised or reversed [line items]            
Discount rate applied to cash flow projections   10.90%     10.70%  
Gas Cylinders            
Disclosure of impairment loss recognised or reversed [line items]            
Goodwill 20.5       $ 18.9 22.3
Gas Cylinders | Luxfer Gas Cylinders            
Disclosure of impairment loss recognised or reversed [line items]            
Goodwill 19.5       17.9  
Gas Cylinders | Superform            
Disclosure of impairment loss recognised or reversed [line items]            
Goodwill 1.0       1.0  
Elektron            
Disclosure of impairment loss recognised or reversed [line items]            
Goodwill 39.1       38.0 $ 39.9
Luxfer MEI Technologies operations            
Disclosure of impairment loss recognised or reversed [line items]            
Goodwill 5.4       3.9  
Luxfer Magtech operations            
Disclosure of impairment loss recognised or reversed [line items]            
Goodwill $ 33.7          
Magnesium Elektron operations            
Disclosure of impairment loss recognised or reversed [line items]            
Goodwill         $ 34.1