Represents the length of a fiscal quarter of the reporting entity.

No definition available.

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Namespace Prefix:	mni_
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Period Type:	duration

- Definition

Number of media companies operated by the entity.

+ References

No definition available.

+ Details

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Namespace Prefix:	mni_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

The number of states in which the entity has operations.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
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- 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)
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Data Type:	num:percentItemType
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Period Type:	instant

- References

No definition available.

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Data Type:	xbrli:stringItemType
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Period Type:	duration

- References

No definition available.

+ Details

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Period Type:	duration

- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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

- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

+ Details

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

- Details

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SIGNIFICANT ACCOUNTING POLICIES (Details) $ in Thousands	3 Months Ended	6 Months Ended
SIGNIFICANT ACCOUNTING POLICIES (Details) $ in Thousands	Jun. 25, 2017 USD ($) company item	Jun. 25, 2017 USD ($) company item	Jul. 31, 2017	Dec. 25, 2016 USD ($)
Investments in Unconsolidated Companies Activity
Number of media companies \| company	30	30
Number of states \| item	14	14
Length of fiscal quarter	91 days	182 days
Long-term debt fair value disclosure
Estimated fair value of long-term debt	$ 857,300	$ 857,300		$ 844,000
Long-term debt	$ 833,000	$ 833,000		$ 846,164
Career Builder LLC
Investments in Unconsolidated Companies Activity
Ownership interest (as a percent)	15.00%	15.00%
Career Builder LLC \| Scenario, Forecast
Investments in Unconsolidated Companies Activity
Ownership interest (as a percent)			3.60%