Post-effective amendment to a registration statement that is not immediately effective upon filing

Supplemental Disclosures to Consolidated Statements of Cash Flows - Schedule of Cash Flow, Supplemental Disclosures (Details)

v3.22.0.1
Supplemental Disclosures to Consolidated Statements of Cash Flows - Schedule of Cash Flow, Supplemental Disclosures (Details) - USD ($)
$ in Millions
 2 Months Ended 4 Months Ended 12 Months Ended
Dec. 31, 2021
Oct. 19, 2021
Jun. 30, 2021
Jun. 30, 2020
Jun. 30, 2019
Jun. 30, 2018
Cash Paid For:            
Cash paid for interest $ 5.5 $ 10.0 $ 37.4 $ 39.2 $ 39.2  
Cash paid for income taxes 2.9 4.3 19.3 10.6 11.3  
Non-Cash Investing and Financing Activities:            
Contingent consideration from acquisitions 0.5 0.8 0.0 0.0 0.0  
Property, plant, and equipment purchases in accounts payable 0.1 (1.8) 3.2 2.0 2.7  
Acquisition purchases in accrued expense and other liabilities 0.0 0.1 2.1 2.8 0.0  
Accounts payable converted to note payable to third parties 0.0 0.0 0.0 0.0 0.2  
Common Shares issued to Mirion Sellers in Mirion Business Combination 420.7 0.0 0.0 0.0 0.0  
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents [Abstract]            
Cash and cash equivalents 84.0 101.8 101.1 118.4 35.8  
Restricted cash—current 0.6 0.8 0.8 1.1 1.4  
Restricted cash—non-current 0.7 0.5 0.5 0.5 0.4  
Total cash, cash equivalents, and restricted cash shown in the statements of cash flow $ 85.3 $ 103.1 $ 102.4 $ 120.0 $ 37.6 $ 35.9