Quarterly report pursuant to Section 13 or 15(d)

Intangible Assets and Goodwill Intangible Assets (Details)

v3.19.1
Intangible Assets and Goodwill Intangible Assets (Details) - USD ($)
 3 Months Ended 6 Months Ended 12 Months Ended
Mar. 31, 2019
Mar. 31, 2019
Mar. 31, 2018
Sep. 30, 2018
Intangible Assets [Line Items]        
Finite-Lived Intangible Assets, Gross $ 608,900,000 $ 608,900,000   $ 602,500,000
Finite-Lived Intangible Assets, Accumulated Amortization 258,600,000 258,600,000   242,800,000
Impairment of Intangible Assets, Indefinite-lived (Excluding Goodwill)     $ 4,600,000.0  
Intangible Assets, Gross (Excluding Goodwill) 735,900,000     730,100,000
Trade Names [Member]        
Intangible Assets [Line Items]        
Indefinite-lived Intangible Assets (Excluding Goodwill) 127,000,000 $ 127,000,000   127,600,000
After Tax [Member]        
Intangible Assets [Line Items]        
Impairment of Intangible Assets, Indefinite-lived (Excluding Goodwill)     $ 3,500,000.0  
Minimum        
Intangible Assets [Line Items]        
Finite-Lived Intangible Asset, Useful Life   3 years    
Maximum        
Intangible Assets [Line Items]        
Finite-Lived Intangible Asset, Useful Life   21 years    
Trade Names [Member]        
Intangible Assets [Line Items]        
Finite-Lived Intangible Assets, Gross 200,000 $ 200,000   200,000
Finite-Lived Intangible Assets, Accumulated Amortization 200,000 200,000   200,000
Customer Relationships [Member]        
Intangible Assets [Line Items]        
Finite-Lived Intangible Assets, Gross 469,200,000 469,200,000   464,500,000
Finite-Lived Intangible Assets, Accumulated Amortization 158,800,000 158,800,000   148,400,000
Technology-Based Intangible Assets [Member]        
Intangible Assets [Line Items]        
Finite-Lived Intangible Assets, Gross 78,200,000 78,200,000   79,600,000
Finite-Lived Intangible Assets, Accumulated Amortization 47,300,000 47,300,000   45,100,000
Computer Software, Intangible Asset [Member]        
Intangible Assets [Line Items]        
Finite-Lived Intangible Assets, Gross 58,500,000 58,500,000   58,000,000
Finite-Lived Intangible Assets, Accumulated Amortization 50,600,000 50,600,000   48,900,000
Other Intangible Assets [Member]        
Intangible Assets [Line Items]        
Finite-Lived Intangible Assets, Gross 2,800,000 2,800,000   200,000
Finite-Lived Intangible Assets, Accumulated Amortization 1,700,000 1,700,000   $ 200,000
Burnaby Machine & Mill Equipment Ltd. [Member]        
Intangible Assets [Line Items]        
Indefinite-lived Intangible Assets (Excluding Goodwill) $ 14,000,000 $ 14,000,000