Capital Stock and Earnings Per Share (OMH Only) - Narrative (Details)	6 Months Ended
Jun. 30, 2025 class
OMH
Class of Stock [Line Items]
Number of classes of authorized stock	2
OMFC
Class of Stock [Line Items]
Number of classes of authorized stock	2

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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+ Details