XML 72 R62.htm IDEA: XBRL DOCUMENT
v3.23.1

Subsequent Events (Details) - Litigation and Commercial Claims - Subsequent Event - Various Pipeline Projects for Texas Customer - Texas Customer $ in Millions | Apr. 25, 2023 USD ($)
--- | ---
Subsequent Event [Line Items] |
Settlement liability | $ 0.3
Damages no longer sought | $ 1.4

X
- Definition Loss Contingency, Damages No Longer Sought, Value + References No definition available. + Details
Name: | mg_LossContingencyDamagesNoLongerSoughtValue
Namespace Prefix: | mg_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount awarded to other party in judgment or settlement of litigation. + References No definition available. + Details
Name: | us-gaap_LitigationSettlementAmountAwardedToOtherParty
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event. + References No definition available. + Details
Name: | us-gaap_SubsequentEventLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_LossContingenciesByNatureOfContingencyAxis=us-gaap_CollectibilityOfReceivablesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_LitigationCaseAxis=mg_VariousPipelineProjectsForTexasCustomerMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_MajorCustomersAxis=mg_TexasCustomerMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |