Annual report pursuant to Section 13 and 15(d)

Financing Agreements - Narrative (Details)

v3.21.2
Financing Agreements - Narrative (Details)
12 Months Ended
Jun. 14, 2021
USD ($)
Mar. 03, 2021
USD ($)
Jun. 16, 2020
USD ($)
Jan. 10, 2020
USD ($)
Sep. 25, 2019
USD ($)
Dec. 15, 2014
USD ($)
Jul. 09, 2010
USD ($)
Sep. 30, 2021
USD ($)
Sep. 30, 2020
USD ($)
Sep. 30, 2019
USD ($)
Sep. 30, 2021
EUR (€)
Sep. 15, 2020
Sep. 30, 2018
USD ($)
Mar. 08, 2018
EUR (€)
Maturities of long-term debt                            
2022               $ 0            
2023               0            
2024               0            
2025               500,000,000.0            
2026               $ 375,000,000.0            
Debt Instrument [Line Items]                            
Debt Instrument, Covenant Terms, Maximum Ratio of Indebtedness to Earnings before Interest, Taxes, Depreciation, and Amortization               3.5            
Debt Instrument, Covenant Terms, Minimum Ratio of Earnings before Interest, Taxes, Depreciation, and Amortization to Interest Expense               3.00            
Amortization of deferred financing costs               $ 7,200,000 $ 3,900,000 $ 6,800,000        
Line of Credit Facility, Maximum Borrowing Capacity, Increase       $ 25,000,000.0                    
Long-term Debt               1,212,900,000 1,552,600,000          
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents $ 350,000,000.0             450,900,000 $ 311,800,000 $ 399,400,000     $ 56,500,000  
$900.0 revolving credit facility (excluding outstanding letters of credit)                            
Debt Instrument [Line Items]                            
Letters of credit outstanding               16,400,000            
Remaining borrowing capacity available under the credit facility               $ 883,600,000            
Weighted average interest rates (as a percent)               2.28% 2.76% 2.54%        
Weighted average facility fee (as a percent)               0.22% 0.26% 0.12%        
Long-term Debt               $ 0 $ 0          
Other Credit Arrangements                            
Debt Instrument [Line Items]                            
Maximum borrowing capacity               411,500,000            
Amount of credit facility utilized for providing bank guarantees               254,000,000.0            
2010 Notes                            
Debt Instrument [Line Items]                            
Debt issued         $ 375,000,000.0     375,000,000.0            
$150.0 senior unsecured notes                            
Debt Instrument [Line Items]                            
Debt issued             $ 150,000,000.0              
Percentage of the principal amount at which the notes are redeemable due to a change of control             101.00%              
$100.0 Series A Notes                            
Debt Instrument [Line Items]                            
Debt issued           $ 100,000,000.0                
Stated interest rate           4.60%                
Redemption price, percentage           100.00%                
Unamortized debt issuance costs               200,000 300,000          
Long-term Debt               99,800,000 99,700,000          
350 Million Senior Unsecured Notes                            
Debt Instrument [Line Items]                            
Debt issued   $ 350,000,000.0                        
Stated interest rate   3.75%                        
Redemption price, percentage   101.00%                        
Long-term Debt               345,800,000 $ 0          
Deferred financing costs   $ 4,200,000                        
350 Million Senior Unsecured Notes | Debt Instrument, Redemption, Period One                            
Debt Instrument [Line Items]                            
Redemption price, percentage   101.875%                        
350 Million Senior Unsecured Notes | Debt Instrument, Redemption, Period Two                            
Debt Instrument [Line Items]                            
Redemption price, percentage   101.25%                        
350 Million Senior Unsecured Notes | Debt Instrument, Redemption, Period Three                            
Debt Instrument [Line Items]                            
Redemption price, percentage   100.625%                        
350 Million Senior Unsecured Notes | Debt Instrument, Redemption, Period Four                            
Debt Instrument [Line Items]                            
Redemption price, percentage   100.00%                        
350 Million Senior Unsecured Notes | Debt Instrument, Redemption, Period Five                            
Debt Instrument [Line Items]                            
Redemption price, percentage   103.75%                        
Debt Instrument, Redemption Price, Option, Percentage of Principal Available to be Redeemed   40.00%                        
HI_500TermLoan                            
Debt Instrument [Line Items]                            
Debt issued               $ 500,000,000.0            
Weighted average interest rates (as a percent)               2.65% 2.99%          
HI_225TermLoan                            
Debt Instrument [Line Items]                            
Debt issued               $ 225,000,000.0            
Weighted average interest rates (as a percent)               2.63% 2.86%          
Syndicated Credit Facility | $900.0 revolving credit facility (excluding outstanding letters of credit)                            
Debt Instrument [Line Items]                            
Maximum borrowing capacity | €                           € 150,000,000.0
Unamortized debt issuance costs               $ 500,000            
Syndicated Credit Facility | Letter of Credit                            
Debt Instrument [Line Items]                            
Maximum borrowing capacity | €                     € 175,000,000.0      
2020 Notes                            
Debt Instrument [Line Items]                            
Debt issued     $ 400,000,000.0         400.0            
Stated interest rate     5.75%                      
Redemption price, percentage     101.00%                      
Amortization of deferred financing costs     $ 4,200,000                      
2020 Notes | Debt Instrument, Redemption, Period One                            
Debt Instrument [Line Items]                            
Redemption price, percentage   102.875%                        
2020 Notes | Debt Instrument, Redemption, Period Two                            
Debt Instrument [Line Items]                            
Redemption price, percentage   101.438%                        
2020 Notes | Debt Instrument, Redemption, Period Three                            
Debt Instrument [Line Items]                            
Redemption price, percentage   100.00%                        
2020 Notes | 2010 Notes                            
Debt Instrument [Line Items]                            
Unamortized debt issuance costs               4,200,000 $ 5,200,000          
Long-term Debt               395,800,000 394,800,000          
$500.0 Term Loan | Term loans                            
Debt Instrument [Line Items]                            
Unamortized debt issuance costs               1,300,000            
Long-term Debt               0 473,700,000          
$225.0 Term Loan | Term loans                            
Debt Instrument [Line Items]                            
Unamortized debt issuance costs               4,200,000            
Long-term Debt               0 213,400,000          
2019 Notes | 2010 Notes                            
Debt Instrument [Line Items]                            
Debt issued         $ 375,000,000.0                  
Stated interest rate         4.50%             5.00%    
Notes issued at a discount         $ 0.6                  
Effective annual interest rate (as a percent)         4.53%                  
Debt Instrument, Interest Rate, Stated Percentage, Increase In Rate For Each Bond Rating Downgrade         0.25%                  
Unamortized debt issuance costs               3,100,000 3,700,000          
Long-term Debt         $ 374,400,000     371,500,000 $ 370,800,000          
$150.0 senior unsecured notes | 2010 Notes                            
Debt Instrument [Line Items]                            
Unamortized debt issuance costs               300,000            
Revolver | $900.0 revolving credit facility (excluding outstanding letters of credit) | Milacron                            
Debt Instrument [Line Items]                            
Borrowings under facilities               $ 650,000,000.0            
Amendment To Credit Agreements                            
Debt Instrument [Line Items]                            
Debt Instrument, Covenant Terms, Maximum Ratio of Indebtedness to Earnings before Interest, Taxes, Depreciation, and Amortization 3.50                          
Debt Instrument, Covenant Terms, Maximum Ratio of Indebtedness to Earnings before Interest, Taxes, Depreciation, and Amortization, Increase To Ratio 4.00                          
Amendment To Credit Agreements | LIBO                            
Debt Instrument [Line Items]                            
Debt Instrument, Floor Base Rate 0.00%                          
Amendment To Credit Agreements | Base Rate                            
Debt Instrument [Line Items]                            
Debt Instrument, Floor Base Rate 1.00%                          
L/G Facility Agreement Amendment                            
Debt Instrument [Line Items]                            
Debt Instrument, Covenant Terms, Maximum Ratio of Indebtedness to Earnings before Interest, Taxes, Depreciation, and Amortization               4.00            
Debt Instrument, Covenant Terms, Minimum Ratio of Earnings before Interest, Taxes, Depreciation, and Amortization to Interest Expense               3.00