Represents the number of phases in the trial.

No definition available.

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Namespace Prefix:	mni_
Data Type:	xbrli:integerItemType
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- Definition

Represents the number of wholly-owned subsidiaries.

+ References

No definition available.

+ Details

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Namespace Prefix:	mni_
Data Type:	xbrli:integerItemType
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Period Type:	duration

- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66011266&loc=d3e33918-111571

+ Details

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Period Type:	instant

- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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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Data Type:	xbrli:stringItemType
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Period Type:	duration

- Definition

Number of plaintiffs that have filed claims pertaining to a loss contingency.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Details

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

- Details

Name:	us-gaap_LitigationCaseAxis=mni_SacramentoCaseMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LitigationCaseAxis=mni_FresnoCaseMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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COMMITMENTS AND CONTINGENCIES - Legal Proceedings (Details) $ in Millions	1 Months Ended			6 Months Ended
	Jan. 31, 2016 subsidiary	Feb. 28, 2009 item	Dec. 31, 2008 item	Jun. 25, 2017 USD ($) item
Letter of credit
Contingencies
Outstanding letters of credit \| $				$ 28.7
"Sacramento Case"
Contingencies
Number of carriers		5,000
Number of phases				3
"Fresno Case"
Contingencies
Number of carriers			3,500
Number of phases				2
PNC
Contingencies
Number of subsidiaries \| subsidiary	3
Ownership interest (as a percent)	27.00%