Debt - Narrative (Details) - USD ($) $ in Thousands	6 Months Ended
Debt - Narrative (Details) - USD ($) $ in Thousands	Jun. 30, 2025	Jun. 30, 2024
Senior Notes \| 5.25% Senior Notes Due 2028
Debt Instrument [Line Items]
Total interest payments	$ 17,100	$ 17,100

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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MGIC INVESTMENT CORP 10-Q