Mirion Technologies, Inc. Quarterly report pursuant to Section 13 or 15(d)

Quarterly report pursuant to Section 13 or 15(d)

Borrowings - Narrative (Details)

Borrowings - Narrative (Details) $ / shares in Units, € in Millions, $ in Millions		3 Months Ended			12 Months Ended
	Oct. 20, 2021 USD ($) $ / shares shares	Mar. 31, 2022 USD ($)	Mar. 31, 2022 EUR (€)	Mar. 31, 2021 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2021 EUR (€)	Mar. 31, 2022 EUR (€)	Dec. 31, 2021 EUR (€)	Jun. 30, 2021 USD ($)	Jun. 30, 2021 EUR (€)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2019 EUR (€)	Jul. 31, 2019 USD ($)	May 31, 2019 USD ($)	May 31, 2019 CAD ($)
Debt Instrument [Line Items]
Fair market value of credit agreement		$ 818,600,000			$ 825,200,000
Amortization expense				$ 1,000,000
Debt instrument, overdraft facilities amount		0			0
Accounts receivable, held-for-sale		8,900,000			9,100,000		€ 8.0	€ 8.0
Other short-term borrowings		$ 0			400,000
Plus Accrued Paid In Kind Interest Notes \| Shareholder
Debt Instrument [Line Items]
Interest rate		11.50%					11.50%
Related party debt notes authorized to be issued amount		$ 900,000,000
Plus Accrued Paid In Kind Interest Notes \| Management
Debt Instrument [Line Items]
Related party debt notes authorized to be issued amount		5,000,000
Letter of Credit
Debt Instrument [Line Items]
Line of credit facility, current borrowing capacity		75,000,000			79,700,000		€ 67.5	€ 70.3
Proceeds from lines of credit		48,100,000	€ 43.3		42,700,000	€ 37.7
Restricted cash		$ 3,000,000			$ 1,300,000
Letter of Credit \| Minimum
Debt Instrument [Line Items]
Interest rate		0.50%					0.50%
Letter of Credit \| Maximum
Debt Instrument [Line Items]
Interest rate		2.00%					2.00%
2021 Credit Agreement \| Secured Debt
Debt Instrument [Line Items]
Loan amount		$ 830,000,000
2021 Credit Agreement \| Revolving Credit Facility
Debt Instrument [Line Items]
Loan amount		$ 90,000,000
Line of credit facility, unused capacity, commitment fee percentage		0.50%	0.50%		0.50%	0.50%
Line of credit facility, stepdowns, commitment fee percentage		0.375%	0.375%
Line of credit facility, commitment fee percentage		0.25%	0.25%
Leverage ratio		7.00	7.00
Revolving credit facility of exceed revolving credit commitment, percentage		40.00%	40.00%
Loan term					5 years			5 years
Maximum borrowing capacity		$ 82,000,000			$ 81,900,000
Debt issuance costs		1,800,000
Amortization expense		1,000,000
Write off of debt issuance cost				400,000
2021 Credit Agreement \| Revolving Credit Facility \| Maximum \| London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate					2.75%	2.75%
2021 Credit Agreement \| Term Loan Facility
Debt Instrument [Line Items]
Loan term					7 years			7 years
Debt instrument, quarterly repayment, percentage					0.25%			0.25%
Repayments of term loan		400,000			$ 1,700,000
Term loan, amount outstanding		827,900,000			$ 828,300,000
Debt issuance costs		$ 21,700,000
Write off of debt issuance cost				$ 15,400,000
2021 Credit Agreement \| Term Loan Facility \| Adjusted LIBOR
Debt Instrument [Line Items]
Interest rate		3.25%			3.25%		3.25%	3.25%
2021 Credit Agreement \| Term Loan Facility \| Minimum \| London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate					0.50%	0.50%
2021 Credit Agreement \| Term Loan Facility \| Maximum \| London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate					2.75%	2.75%
2021 Credit Agreement \| Letter of Credit
Debt Instrument [Line Items]
Maximum borrowing capacity		$ 8,000,000			$ 8,100,000
2019 Credit Facility
Debt Instrument [Line Items]
Debt instruments, interest rate period									3 months	3 months
2019 Credit Facility \| Secured Debt
Debt Instrument [Line Items]
Loan amount												$ 450,000,000
2019 Credit Facility \| Revolving Credit Facility
Debt Instrument [Line Items]
Loan amount												90,000,000
Line of credit facility, unused capacity, commitment fee percentage				0.50%
Loan term				5 years
2019 Credit Facility \| Revolving Credit Facility \| Maximum \| London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate				4.00%
2019 Credit Facility \| Term Loan Facility
Debt Instrument [Line Items]
Loan amount \| €													€ 125.0
2019 Credit Facility \| USD Term Loan
Debt Instrument [Line Items]
Loan amount											$ 225,000,000	$ 66,000,000		$ 34,000,000
Loan term				7 years
Debt instrument, quarterly repayment, percentage				0.25%
2019 Credit Facility \| USD Term Loan \| Adjusted LIBOR
Debt Instrument [Line Items]
Interest rate				4.27%
2019 Credit Facility \| USD Term Loan \| Maximum \| London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate				4.00%
2019 Credit Facility \| London Interbank Offered Rate (LIBOR) \| Eurodollar
Debt Instrument [Line Items]
Repayment of debt				$ 1,900,000
2019 Credit Facility \| Euro Term Loan
Debt Instrument [Line Items]
Debt instrument, quarterly repayment, percentage				0.25%
2019 Credit Facility \| Euro Term Loan \| Eurodollar
Debt Instrument [Line Items]
Loan term				7 years
Interest rate				4.25%
Repayment of debt				$ 400,000
2019 Credit Facility \| Euro Term Loan \| Maximum \| London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate				4.25%
2019 Credit Facility \| NRG Loan
Debt Instrument [Line Items]
Loan amount									$ 7,400,000	€ 7.2
Interest rate									2.00%	2.00%
2019 Credit Facility \| Canadian Financial Institution
Debt Instrument [Line Items]
Loan amount															$ 1,300,000	$ 1.7
Interest rate															4.15%	4.15%
GSAH
Debt Instrument [Line Items]
Purchase consideration	$ 2,600,000,000
Beginning balance, cash consideration paid by GSAH	1,300,000,000
Equity interest, value	$ 400,000,000
Share price (in dollars per share) \| $ / shares	$ 10.45
GSAH \| Common Class A
Debt Instrument [Line Items]
Business acquisition equity interest issued or issuable (in shares) \| shares	30,401,902
GSAH \| Common Class B
Debt Instrument [Line Items]
Business acquisition equity interest issued or issuable (in shares) \| shares	8,560,540