Gross amount of debt redeemed through at par through a tender offer.

No definition available.

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Namespace Prefix:	mni_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ 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 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
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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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Fair value amount of debt instrument that was repurchased.

+ References

No definition available.

+ Details

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

- Definition

Face (par) amount of the original debt instrument that was repurchased.

+ References

No definition available.

+ Details

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

- Definition

Gross amount of debt extinguished.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 50
-Section 40
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=49170532&loc=d3e12317-112629

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 50
-Section 40
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=49170532&loc=d3e12355-112629

+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

Reflects the difference between the fair value of payments made to legally extinguish a debt and its carrying value at that time. This item excludes the write-off of amounts previously capitalized as debt issuance costs.

+ References

+ Details

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

- Definition

Write-off of amounts previously capitalized as debt issuance cost in an extinguishment of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.8)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

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Namespace Prefix:
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- Details

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LONG-TERM DEBT - Debt Redemptions, Repurchases and Loss on Extinguishment of Debt (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended	9 Months Ended
	Jul. 16, 2018	Sep. 30, 2018	Sep. 24, 2017	Jul. 01, 2018	Sep. 30, 2018	Sep. 24, 2017	Dec. 31, 2017
LONG-TERM DEBT
Face value debt reduced		$ 439,630	$ 68,550		$ 439,630	$ 68,550
Amount of debt redeemed			16,900			16,900
Gross gain on extinguishment of debt		68,700
Gain (loss) on extinguishment of debt, net		36,286	(1,831)		30,918	(2,700)
9.00% senior secured notes due in 2022
LONG-TERM DEBT
Face value debt reduced		$ 439,630	51,685		$ 439,630	51,685
Interest rate (as a percent)		9.00%			9.00%		9.00%
Debt redeemed through tender offer		$ 344,100	35,000	$ 500		50,000
Amount of debt redeemed	$ 344,100		1,700	$ 75,000		1,700
Debt repurchased privately							$ 20,000
5.750% notes due in 2017
LONG-TERM DEBT
Face value debt reduced			$ 16,865			$ 16,865
Interest rate (as a percent)		5.75%	5.75%		5.75%	5.75%
Debentures
LONG-TERM DEBT
Gross gain on extinguishment of debt		$ 68,700			$ 68,700
Write off of unamortized discounts		$ 32,300			$ 32,300