XML 45 R41.htm IDEA: XBRL DOCUMENT v2.4.0.8

Subsequent Event (Details) (Subsequent Event [Member], Revolving Credit Facility [Member], Credit Facility due 2018 [Member], USD $)	0 Months Ended
	Jul. 02, 2013
Subsequent Event [Line Items]
Debt instrument, face amount	$ 200,000,000
Debt instrument, term	5 years
Debt to Total Capital Ratio, Under 15% [Member]
Subsequent Event [Line Items]
Line of credit facility, commitment fee percentage for unused portions	0.125%
Debt instrument, ratio of indebtedness to total capital	15.00%
Debt to Total Capital Ratio, Above 25% [Member]
Subsequent Event [Line Items]
Line of credit facility, commitment fee percentage for unused portions	0.225%
Debt instrument, ratio of indebtedness to total capital	25.00%
LIBOR [Member] | Debt to Total Capital Ratio, Under 15% [Member]
Subsequent Event [Line Items]
Debt instrument, description of variable rate basis	LIBOR
Debt instrument, basis spread on variable rate	1.125%
LIBOR [Member] | Debt to Total Capital Ratio, Above 25% [Member]
Subsequent Event [Line Items]
Debt instrument, description of variable rate basis	LIBOR
Debt instrument, basis spread on variable rate	1.625%

X

- Definition

Debt Instrument, Ratio of Indebtedness to Total Capital

+ References

No definition available.

+ Details

Name:	mcy_DebtInstrumentRatioofIndebtednesstoTotalCapital
Namespace Prefix:	mcy_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

X

- Definition

The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

+ References

No definition available.

+ Details

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

X

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399



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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 55

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=6584090&loc=d3e28878-108400

+ Details

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

X

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentTerm
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

X

- 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

X

- Details

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