Damages Claimed.

No definition available.

Name:	mhfi_DamagesClaimed
Namespace Prefix:	mhfi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Rating fees Paid.

+ References

No definition available.

+ Details

Name:	mhfi_RatingFeesPaid
Namespace Prefix:	mhfi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Sale Leaseback Transaction, Interest Expense

+ References

No definition available.

+ Details

Name:	mhfi_SaleLeasebackTransactionInterestExpense
Namespace Prefix:	mhfi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- 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)

-URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571

+ Details

Name:	us-gaap_EquityMethodInvestmentOwnershipPercentage
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

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

- Definition

The portion of the gain that will be recorded as income or a reduction in rent expense in future periods less amounts recognized in the current period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 40

-Section 35

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=35688829&loc=d3e50609-112754

+ Details

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

- Definition

The amount of the current period expense recorded for use of the property in connection with the transaction involving the sale of property to another party and the lease of the property back to the seller.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6453985&loc=d3e41499-112717

+ Details

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

- Details

Name:	us-gaap_LitigationCaseAxis=mhfi_ParmalatMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Commitments and Contingencies (Details) € in Millions, $ in Millions	1 Months Ended		3 Months Ended	6 Months Ended
	Dec. 31, 2012 EUR (€)	Jun. 30, 2011 EUR (€)	Jun. 30, 2015 USD ($)	Jun. 30, 2015 USD ($)	Dec. 31, 2013 USD ($)	Oct. 31, 2005 EUR (€)	Dec. 31, 2003
Loss Contingencies [Line Items]
Equity method investment ownership percentage							45.00%
Deferred gain			$ 4	$ 4	$ 60
Amortized deferred gain			2	4
Interest expense (less than $1 million for three months and six months ended June 30, 2015)			$ 1	$ 1
Parmalat [Member]
Loss Contingencies [Line Items]
Damages claimed \| €						€ 4,100.0
Rating fees paid \| €	€ 1.1	€ 0.8