Description of percentage of secured lien on borrowings under credit facility.

No definition available.

Name:	mcep_DescriptionOfPercentageOfSecuredLienOnBorrowingsUnderCreditFacility
Namespace Prefix:	mcep_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Line of Credit facility basis spread on LIBOR.

+ References

No definition available.

+ Details

Name:	mcep_LineOfCreditFacilityBasisSpreadOnLibor
Namespace Prefix:	mcep_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Line of credit facility basis spread on prime rate.

+ References

No definition available.

+ Details

Name:	mcep_LineOfCreditFacilityBasisSpreadOnPrimeRate
Namespace Prefix:	mcep_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Margin on Adjusted LIBOR Based on Borrowing Usage.

+ References

No definition available.

+ Details

Name:	mcep_MarginOnAdjustedLiborBasedOnBorrowingUsage
Namespace Prefix:	mcep_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Margin on LIBOR based on borrowing usage.

+ References

No definition available.

+ Details

Name:	mcep_MarginOnLiborBasedOnBorrowingUsage
Namespace Prefix:	mcep_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Minimum Current Ratio

+ References

No definition available.

+ Details

Name:	mcep_MinimumCurrentRatio
Namespace Prefix:	mcep_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	duration

- Definition

Omit before interest and tax.

+ References

No definition available.

+ Details

Name:	mcep_RatioOfIndebtednessToEarnings
Namespace Prefix:	mcep_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	duration

- 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 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.16)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 20, 22

-Article 5

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.16)

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

+ Details

Name:	us-gaap_LineOfCredit
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

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 210.5-02.19(b),22(b))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

+ Details

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

- Definition

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

+ References

+ Details

Name:	us-gaap_LineOfCreditFacilityExpirationDate1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

The effective interest rate during the reporting period.

+ References

+ Details

Name:	us-gaap_LineOfCreditFacilityInterestRateDuringPeriod
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_LineOfCreditFacilityLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- 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

+ Details

Name:	us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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

Name:	us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_RangeAxis=us-gaap_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=us-gaap_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableRateAxis=us-gaap_FederalFundsEffectiveSwapRateMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableRateAxis=us-gaap_LondonInterbankOfferedRateLIBORMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Debt - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Dec. 31, 2014	Apr. 02, 2015
Line of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity	$ 250.0
Senior secured revolving facility, expiring date	Nov. 05, 2018
Line of Credit Facility, Current Borrowing Capacity		240.0
Borrowings under the facility secure by liens	not less than 80%
Revolving credit facility borrowings, outstanding	203.0us-gaap_LineOfCredit
Minimum current ratio required under credit facility	1.0mcep_MinimumCurrentRatio
Average effective rate	2.69%
Minimum [Member]
Line of Credit Facility [Line Items]
Margin	0.75%
Unused portion of borrowing base, percentage fee	0.375%
Maximum [Member]
Line of Credit Facility [Line Items]
Leverage ratio required under credit facility	4.0
Margin	1.75%
Unused portion of borrowing base, percentage fee	0.50%
Federal Funds Effective Swap Rate [Member]
Line of Credit Facility [Line Items]
Federal fund effective rate	0.50%
London Interbank Offered Rate (LIBOR) [Member]
Line of Credit Facility [Line Items]
Federal fund effective LIBOR	1.00%
London Interbank Offered Rate (LIBOR) [Member] \| Minimum [Member]
Line of Credit Facility [Line Items]
Applicable margin rate	1.75%
London Interbank Offered Rate (LIBOR) [Member] \| Maximum [Member]
Line of Credit Facility [Line Items]
Applicable margin rate	2.75%
Subsequent Event [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Current Borrowing Capacity			$ 220.0