XML 53 R41.htm IDEA: XBRL DOCUMENT
v3.25.2

Reinsurance - Quota Share Transactions Terms (Details) | 6 Months Ended
--- | ---
Jun. 30, 2025
2020 QSR and 2021 QSR - 2021 NIW |
Effects of Reinsurance [Line Items] |
Quota Share % | 14.80%
Annual Loss Ratio to Exhaust Profit Commission (as a percent) | 69.00%
Cede rate, option 1 (as a percent) | 12.30%
Cede rate, option 2 (as a percent) | 10.00%
2021 QSR and 2022 QSR - 2021 NIW |
Effects of Reinsurance [Line Items] |
Quota Share % | 11.10%
Annual Loss Ratio to Exhaust Profit Commission (as a percent) | 69.00%
Cede rate, option 1 (as a percent) | 9.40%
Cede rate, option 2 (as a percent) | 7.00%
2021 QSR and 2022 QSR - 2022 NIW |
Effects of Reinsurance [Line Items] |
Quota Share % | 15.00%
Annual Loss Ratio to Exhaust Profit Commission (as a percent) | 57.50%
Cede rate, option 1 (as a percent) | 12.50%
Cede rate, option 2 (as a percent) | 10.00%
2022 QSR and 2023 QSR - 2022 NIW |
Effects of Reinsurance [Line Items] |
Quota Share % | 15.00%
Annual Loss Ratio to Exhaust Profit Commission (as a percent) | 62.00%
Cede rate, option 1 (as a percent) | 12.50%
Cede rate, option 2 (as a percent) | 10.00%
2022 QSR and 2023 QSR - 2023 NIW |
Effects of Reinsurance [Line Items] |
Quota Share % | 15.00%
Annual Loss Ratio to Exhaust Profit Commission (as a percent) | 62.00%
Cede rate, option 1 (as a percent) | 12.50%
Cede rate, option 2 (as a percent) | 10.00%
2023 QSR - 2023 NIW |
Effects of Reinsurance [Line Items] |
Quota Share % | 10.00%
Annual Loss Ratio to Exhaust Profit Commission (as a percent) | 58.50%
Cede rate, option 1 (as a percent) | 8.00%
Cede rate, option 2 (as a percent) | 7.00%
2024 QSR - 2024 NIW |
Effects of Reinsurance [Line Items] |
Quota Share % | 30.00%
Annual Loss Ratio to Exhaust Profit Commission (as a percent) | 56.00%
Cede rate, option 1 (as a percent) | 23.00%
Cede rate, option 2 (as a percent) | 15.00%
2025 QSR - 2025 NIW |
Effects of Reinsurance [Line Items] |
Quota Share % | 40.00%
Annual Loss Ratio to Exhaust Profit Commission (as a percent) | 63.00%
Cede rate, option 1 (as a percent) | 30.00%
Cede rate, option 2 (as a percent) | 20.00%
Credit Union QSR Transaction |
Effects of Reinsurance [Line Items] |
Quota Share % | 65.00%
Annual Loss Ratio to Exhaust Profit Commission (as a percent) | 50.00%

X
- Definition Reinsurance, Quota Share Reinsurance Agreement, Terms, Ceding Rate, Percent, Option One + References No definition available. + Details
Name: | mtg_ReinsuranceQuotaShareReinsuranceAgreementTermsCedingRatePercentOptionOne
Namespace Prefix: | mtg_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Reinsurance, Quota Share Reinsurance Agreement, Terms, Ceding Rate, Percent, Option Two + References No definition available. + Details
Name: | mtg_ReinsuranceQuotaShareReinsuranceAgreementTermsCedingRatePercentOptionTwo
Namespace Prefix: | mtg_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Reinsurance, Quota Share Reinsurance Agreement, Terms, Quota Share, Percent + References No definition available. + Details
Name: | mtg_ReinsuranceQuotaShareReinsuranceAgreementTermsQuotaSharePercent
Namespace Prefix: | mtg_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

X
- 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. + References No definition available. + Details
Name: | us-gaap_EffectsOfReinsuranceLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Ratio of non-life losses and loss expenses to non-life net premiums earned. + References No definition available. + Details
Name: | us-gaap_LossRatio
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_CededCreditRiskAxis=mtg_QuotaShareReinsuranceTransaction2020And20212021NIWMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_CededCreditRiskAxis=mtg_QuotaShareReinsuranceTransaction2021And20222021NIWMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_CededCreditRiskAxis=mtg_QuotaShareReinsuranceTransaction2021And20222022NIWMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_CededCreditRiskAxis=mtg_QuotaShareReinsuranceTransaction2022And20232022NIWMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_CededCreditRiskAxis=mtg_QuotaShareReinsuranceTransaction2022And20232023NIWMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_CededCreditRiskAxis=mtg_QuotaShareReinsuranceTransaction20232023NIWMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_CededCreditRiskAxis=mtg_QuotaShareReinsuranceTransaction20242024NIWMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_CededCreditRiskAxis=mtg_QuotaShareReinsuranceTransaction20252025NIWMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_CededCreditRiskAxis=mtg_CreditUnionQuotaShareReinsuranceTransactionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |