Aggregate balance of MSC Holdings LLC PIK Facility

No definition available.

Name:	msc_AggregatebalanceofMSCHoldingsLLCPIKFacility
Namespace Prefix:	msc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Forgiveness of Note Receivable from Parent

+ References

No definition available.

+ Details

Name:	msc_ForgivenessOfNoteReceivableFromParent
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Balance Type:	credit
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- Definition

Non-cash distribution declared to parent

+ References

No definition available.

+ Details

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Balance Type:	debit
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- Definition

Partial proceeds from the Preferred Equity Issuance received

+ References

No definition available.

+ Details

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

- Definition

Remaining proceeds held in reserve from the Preferred Equity Issuance

+ References

No definition available.

+ Details

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Namespace Prefix:	msc_
Data Type:	xbrli:monetaryItemType
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- Definition

Face amount or stated value per share of common stock.

+ 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 210.5-02.29)

-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 30

-Article 5

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

The cash inflow from the issuance of common stock, preferred stock, treasury stock, stock options, and other types of equity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

-URI http://asc.fasb.org/extlink&oid=6513228

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 14

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3255-108585

+ Details

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

- Definition

Number of shares issued which are neither cancelled nor held in the treasury.

+ References

No definition available.

+ Details

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Data Type:	xbrli:sharesItemType
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Period Type:	instant

- Details

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- Details

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Period Type:

Deficit Level 4 (Details) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Class of Stock [Line Items]
shares outstanding	82,556,847us-gaap_SharesOutstanding	82,556,847us-gaap_SharesOutstanding
Common Stock, Par or Stated Value Per Share	$ 0.01	$ 0.01
Forgiveness of Note Receivable from Parent	$ 0	$ 24	$ 0
Non-cash distribution declared to parent	0msc_NonCashDistributionDeclaredToParent	208msc_NonCashDistributionDeclaredToParent	0msc_NonCashDistributionDeclaredToParent
Aggregate balance of MSC Holdings LLC PIK Facility		247
Apollo Affiliates and Other Related Parties [Member]
Class of Stock [Line Items]
Partial proceeds from the Preferred Equity Issuance received			189	189
Remaining proceeds held in reserve from the Preferred Equity Issuance			16	16
Proceeds from Issuance or Sale of Equity			204	204
Notes Receivable From Parent [Member]
Class of Stock [Line Items]
Forgiveness of Note Receivable from Parent		$ 24