Promissory Note Received from Sale Of Property, Plan, and Equipment

No definition available.

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

- Definition

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

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+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

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

+ References

No definition available.

+ Details

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Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of consideration received or receivable for the disposal of assets and liabilities, including discontinued operation.

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Balance Type:	debit
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.

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Period Type:	duration

- Definition

The amount of unfunded commitments for which the entity is obligated, to those certain investments for which net asset value per share is calculated (including by unit, membership interest, or other equity (ownership interest) unit measure) (alternative investments).

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Balance Type:	credit
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- Definition

The cash inflow from a contractual arrangement with the lender, including letter of credit, standby letter of credit and revolving credit arrangements, under which borrowings can be made up to a specific amount at any point in time with maturities due beyond one year or the operating cycle, if longer.

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- Details

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Namespace Prefix:
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- Details

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Balance Type:
Period Type:

- Details

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Namespace Prefix:
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Balance Type:
Period Type:

- Details

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Balance Type:
Period Type:

- Details

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Balance Type:
Period Type:

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- Details

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Financial Instruments (Narrative) (Details) - USD ($) $ in Millions	1 Months Ended		6 Months Ended	12 Months Ended
	Sep. 30, 2024	Mar. 31, 2023	Jun. 30, 2026	Dec. 31, 2025
Brea, California Office Building \| Disposal Group, Disposed of by Sale, Not Discontinued Operations
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Sale price of fixed asset	$ 31.5
Promissory note received from sale of fixed asset	$ 21.4
Clearwater, Florida Office Building \| Disposal Group, Disposed of by Sale, Not Discontinued Operations
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Sale price of fixed asset		$ 19.6
Promissory note received from sale of fixed asset		$ 9.8
Promissory Note
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate (in percent)	7.00%	7.00%
Promissory note, term (in years)	4 years	4 years
Senior unsecured notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Unsecured notes			$ 900.0	$ 375.0
Unsecured credit facility \| Revolving Credit Facility
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Drawn down amount under credit facility			50.0	200.0
Private Equity Funds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Unfunded commitments to VIEs			$ 16.0	$ 4.0