XML 30 R81.htm IDEA: XBRL DOCUMENT
v2.4.0.6

Profit Sharing Plan (Details) (USD $) In Millions, unless otherwise specified | 12 Months Ended
--- | ---
Dec. 31, 2011 | Dec. 31, 2010 | Dec. 31, 2009
Profit Sharing Plan [Abstract] |  |  |
Maximum percentage of compensation employee is allowed to contribute | 15.00% |  |
Matching contributions | $ 7.2 | $ 7.0 | $ 3.1
Value of shares authorized to repurchase for ESOP allocation | $ 0 | $ 1.2 | $ 1.2

X
- Definition Maximum percentage of compensation employee is allowed to contribute to the Plan. + References No definition available. + Details
Name: | mcy_MaximumPercentageOfCompensationEmployeeIsAllowedToContribute
Namespace Prefix: | mcy_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_DeferredCompensationArrangementsAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The amount of payment into the fund established for purposes of making future disbursements to the individual in accordance with the terms and understanding of the deferred compensation arrangement. + References No definition available. + Details
Name: | us-gaap_DeferredCompensationArrangementWithIndividualEmployerContribution
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition An entity will typically disclose the amount of any repurchase obligation. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Statement of Position (SOP) -Number 93-6 -Paragraph 53 -Subparagraph f -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 40 -Section 50 -Paragraph 1 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=6418621&loc=d3e17540-113929 + Details
Name: | us-gaap_EmployeeStockOwnershipPlanESOPRepurchaseObligationAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant