XML 64 R35.htm IDEA: XBRL DOCUMENT
v2.4.0.6

Deferred Policy Acquisition Costs (Tables) | 12 Months Ended
--- | ---
Dec. 31, 2012
Deferred Policy Acquisition Costs Disclosures [Abstract] |
Schedule Of Deferred Policy Acquisition Costs | Deferred policy acquisition costs are as follows:
| December 31,
| 2012 |  | 2011 |  | 2010
| (Amounts in thousands)
Balance, beginning of year | $ | 171,430 |  |  | $ | 170,579 |  |  | $ | 175,866 |
Policy acquisition costs deferred | 492,268 |  |  | 482,572 |  |  | 500,278 |
Amortization | (477,788 | ) |  | (481,721 | ) |  | (505,565 | )
Balance, end of year | $ | 185,910 |  |  | $ | 171,430 |  |  | $ | 170,579 |

X
- Definition Schedule Of Deferred Policy Acquisition Costs [Table Text Block]. + References No definition available. + Details
Name: | mcy_ScheduleOfDeferredPolicyAcquisitionCostsTableTextBlock
Namespace Prefix: | mcy_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

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