XML 87 R70.htm IDEA: XBRL DOCUMENT
v3.21.2

Contracts in Progress - Schedule of cost and billings on uncompleted construction type long term contracts or programs (Detail) - USD ($) $ in Millions | Jun. 30, 2021 | Jun. 30, 2020
--- | --- | ---
Costs in Excess of Billings on Uncompleted Contracts or Programs [Abstract] |  |
Costs incurred on contracts (from inception to completion) | $ 185.8 | $ 152.5
Estimated earnings | 133.2 | 108.9
Contracts in progress | 319.0 | 261.4
Less: billings to date | (261.9) | (209.8)
Less: write-offs | (2.7) | 0.0
Costs in Excess of Billings | $ 54.4 | $ 51.6

X
- Definition Construction contract in progress. + References No definition available. + Details
Name: | mir_ConstructionContractInProgress
Namespace Prefix: | mir_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Contracts write offs amount. + References No definition available. + Details
Name: | mir_ContractsWriteOffsAmount
Namespace Prefix: | mir_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Costs in excess of billings uncompleted construction type contracts. + References No definition available. + Details
Name: | mir_CostsInExcessOfBillingsUncompletedConstructionTypeContracts
Namespace Prefix: | mir_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Costs incurred on contracts. + References No definition available. + Details
Name: | mir_CostsIncurredOnContracts
Namespace Prefix: | mir_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amounts due for billed services rendered or to be rendered, actions taken or to be taken, or a promise to refrain from taking certain actions in accordance with the terms of a legally binding agreement between the Company and, at a minimum, one other party. An example would be amounts billed to customers under contracts or programs but not paid as of the balance sheet date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.3(c)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 912 -SubTopic 310 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=123371682&loc=d3e55302-109406 + Details
Name: | us-gaap_BilledContractReceivables
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- References No definition available. + Details
Name: | us-gaap_CostsInExcessOfBillingsOnUncompletedContractsOrProgramsAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount to be collected within one year of the balance sheet date (or one operating cycle, if longer) from customers in accordance with the contractual provisions of long-term contracts or programs including amounts billed and unbilled as of the balance sheet date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.3(c)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
Name: | us-gaap_ReceivablesLongTermContractsOrPrograms
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant