Debt operating cash flows ratio required to be maintained.

No definition available.

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- Definition

Interest coverage ratio required to maintain under credit facility.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Leverage ratio required to maintain under credit facility.

+ References

No definition available.

+ Details

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- Definition

Line of credit facility expiration month and year.

+ References

No definition available.

+ Details

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- Definition

Notes expiration date.

+ References

No definition available.

+ Details

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- Definition

Reclassification of deferred financing costs from other assets, net to long-term debt, net.

+ References

No definition available.

+ Details

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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

Weighted average interest rate of debt outstanding.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
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- 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
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the 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))
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-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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

- Definition

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

+ References

+ Details

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

- Definition

Date the credit facility terminates, in CCYY-MM-DD format.

+ References

+ Details

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

- Definition

The effective interest rate at the end of the reporting period.

+ References

+ Details

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

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ Details

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

- Definition

The cash inflow from parent as a source of financing that is recorded as additional paid in capital.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
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-Glossary Financing Activities
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of cash outflow for payment of an obligation from a lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
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-Name Accounting Standards Codification
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(f))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

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

- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Balance Type:	credit
Period Type:	instant

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Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_LoansPayableMember
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- Details

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- Details

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

- Details

Name:	us-gaap_LineOfCreditFacilityAxis=mcccb_BankCreditFacilityMember
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Data Type:	na
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Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=mcccb_TermLoanIMember
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- Details

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Name:	us-gaap_CreditFacilityAxis=mcccb_TermLoanAMember
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Name:	us-gaap_CreditFacilityAxis=mcccb_TermLoanHMember
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Debt - Additional Information (Detail) - USD ($)		6 Months Ended	9 Months Ended		12 Months Ended
Debt - Additional Information (Detail) - USD ($)	May 19, 2016	Jun. 30, 2016	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Debt Instrument [Line Items]
Received capital contributions from parent			$ 75,000,000	$ 0
Loss on early extinguishment of debt			(1,156,000)
Outstanding senior notes			500,000,000
Reclassification of deferred financing costs from other assets to long-term debt, net			15,400,000		$ 20,200,000
5 1/2% Senior Notes Due 2021 [Member]
Debt Instrument [Line Items]
Outstanding senior notes			$ 200,000,000
Senior notes expiration date			2021-04
6 3/8% Senior Notes Due 2023 [Member]
Debt Instrument [Line Items]
Outstanding senior notes			$ 300,000,000
Senior notes expiration date			2023-04
Interest Rate Swap [Member]
Debt Instrument [Line Items]
Interest rate on borrowings			1.50%
Expiration period of revolving credit commitments			2018-12
Weighted average interest rate on outstanding borrowings			3.60%
Interest Rate Swap [Member] \| Not Designated as Hedging Instrument [Member]
Debt Instrument [Line Items]
Revolving credit commitment outstanding			$ 600,000,000
Maximum [Member]
Debt Instrument [Line Items]
Required debt to operating cash flow			850.00%
Minimum [Member]
Debt Instrument [Line Items]
Required debt to operating cash flow			1.00%
Loans Payable [Member]
Debt Instrument [Line Items]
Revolving credit commitment outstanding			$ 135,400,000
Mediacom LLC [Member]
Debt Instrument [Line Items]
Received capital contributions from parent	$ 75,000,000
Letter of Credit [Member]
Debt Instrument [Line Items]
Revolving credit commitment outstanding			9,700,000
Bank Credit Facility [Member]
Debt Instrument [Line Items]
Revolving credit commitment outstanding			1,388,000,000
Unused revolving credit commitments			$ 223,400,000
Bank Credit Facility [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Leverage ratio			500.00%
Interest coverage ratio			200.00%
Bank Credit Facility [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Leverage ratio			100.00%
Interest coverage ratio			100.00%
Bank Credit Facility [Member] \| Term Loan I [Member]
Debt Instrument [Line Items]
Repayment of credit facility	245,600,000
Bank Credit Facility [Member] \| Revolving Credit Commitments at Present [Member]
Debt Instrument [Line Items]
Revolving credit commitments	$ 170,600,000		$ 368,500,000
Expiration date of revolving credit commitments			Oct. 10, 2019
Bank Credit Facility [Member] \| Term Loan A [Member]
Debt Instrument [Line Items]
Revolving credit commitment outstanding			$ 145,800,000
Expiration date of revolving credit commitments			Jan. 15, 2021
Bank Credit Facility [Member] \| Term Loan H [Member]
Debt Instrument [Line Items]
Revolving credit commitment outstanding		$ 580,500,000
Expiration date of revolving credit commitments		Jan. 29, 2021
Bank Credit Facility [Member] \| Term Loan J [Member]
Debt Instrument [Line Items]
Revolving credit commitment outstanding			$ 293,300,000
Expiration date of revolving credit commitments			Jun. 30, 2021