Incremental percentage increase (decrease) in the stated rate on a debt instrument.

No definition available.

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

The cash outflow for the extinguishment of long-term borrowing, with the highest claim on the assets of the entity in case of bankruptcy or liquidation, before its maturity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3291-108585

+ Details

Name:	us-gaap_EarlyRepaymentOfSeniorDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
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Period Type:	duration

- Details

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- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_SecuredDebtMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=mcrn_SeniorSecuredAssetBasedRevolvingCreditFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Debt - Additional Information (Details) - Secured Debt [Member] - USD ($)				6 Months Ended
	Apr. 30, 2018	Apr. 27, 2018	Feb. 28, 2018	Jun. 30, 2018
Senior Secured Term Loan Facility Due September 2023 [Member]
Debt Instrument [Line Items]
Early Repayment of Senior Debt	$ 25,000,000		$ 25,000,000	$ 50,000,000
Senior Secured Asset-Based Revolving Credit Facility [Member] \| Domestic Line of Credit [Member]
Debt Instrument [Line Items]
Debt Instrument, Variable Interest Rate		0.50%
Debt Instrument, Fee Amount		0.125%
Line of Credit Facility, Maximum Borrowing Capacity		$ 5,000,000