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Description of Business - Mortgage (Details) - Mortgage - USD ($) $ in Billions | Dec. 31, 2022 | Dec. 31, 2021
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Business Overview [Abstract] |  |
Down payment percent of purchase price | 20.00% |
Equity in home (percent) | 20.00% |
Direct primary mortgage insurance in force | $ 261.0 | $ 246.0
Direct primary mortgage insurance risk in force | $ 66.1 | $ 60.9

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- Definition Business Overview [Abstract] + References No definition available. + Details
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- Definition This element represents the maximum down payment percentage on a home's purchase price that is used to measure the need for private mortgage insurance. + References No definition available. + Details
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- Definition This element represents the maximum equity-ownership percentage on a home's value that is used to measure the need for private mortgage insurance for refinancings. + References No definition available. + Details
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- Definition Statutory Accounting Practices, Risk In Force + References No definition available. + Details
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- Definition Amount of participating insurance in force. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 50 -Section 50 -Paragraph 1 -Subparagraph (a) -URI https://asc.fasb.org/extlink&oid=6483535&loc=d3e16392-158451 + Details
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- Details
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