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

No definition available.

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- 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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3291-108585

+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 50
-Section 40
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=114001942&loc=d3e12355-112629

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 50
-Section 40
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=114001942&loc=d3e12317-112629

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

+ Details

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

+ Details

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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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- Details

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- Details

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- Details

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- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_DomesticLineOfCreditMember
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- Details

Name:	us-gaap_DebtInstrumentAxis=mcrn_SeniorSecuredAssetBasedRevolvingCreditFacilityMember
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Debt - Narrative (Details) - USD ($) $ in Millions							3 Months Ended		9 Months Ended
Debt - Narrative (Details) - USD ($) $ in Millions	Sep. 30, 2019	Jul. 03, 2019	Jul. 31, 2018	Apr. 30, 2018	Apr. 27, 2018	Feb. 28, 2018	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Debt Instrument [Line Items]
Gain (loss) on debt extinguishment							$ 0.7	$ 0.3	$ 0.7	$ 1.0
Senior Secured Term Loan Facility Due September 2023 \| Secured Debt
Debt Instrument [Line Items]
Principal payments	$ 9.5	$ 52.0	$ 25.0	$ 25.0		$ 25.0				75.0
Gain (Loss) on Extinguishment of Debt
Debt Instrument [Line Items]
Gain (loss) on debt extinguishment							$ 0.7	$ 0.3	$ 0.7	$ 1.0
Domestic Line of Credit \| Senior Secured Asset-Based Revolving Credit Facility \| Secured Debt
Debt Instrument [Line Items]
Increase (decrease) in interest rate (as a percent)					0.50%
Commitment fee rate (as a percent)					0.125%
Maximum borrowing capacity					$ 5.0