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Statutory Information - Narrative (Details) | 12 Months Ended
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Dec. 31, 2021 USD ($) jurisdiction | Dec. 31, 2020 USD ($) | Dec. 31, 2019 USD ($)
Statutory capital requirements [Abstract] |  |  |
Number of jurisdictions with risk-to-capital requirements | jurisdiction | 16 |  |
Maximum permitted risk-to-capital ratio commonly applied | 25 to 1 |  |
Risk to capital ratio of combined insurance operations at end of period | 9.5 to 1 |  |
Risk-to-capital ratio on combined insurance operations | 9.5 |  |
Statutory net income | $ 295,811,000 | $ 65,201,000 | $ 305,857,000
Statutory policyholders' surplus | $ 1,220,714,000 | $ 1,339,509,000 | $ 1,619,069,000
Insurance Subsidiaries |  |  |
Statutory capital requirements [Abstract] |  |  |
Percentage of statutory policyholders surplus used to determine maximum allowable dividends | 10.00% |  |
Adjusted statutory net income measurement period | 3 years |  |
Adjusted statutory net income dividend payment measurement period | 2 years |  |
Maximum |  |  |
Statutory capital requirements [Abstract] |  |  |
Risk to capital ratio | 25 |  |
Mortgage Guaranty Insurance Corporation |  |  |
Statutory capital requirements [Abstract] |  |  |
Risk to capital ratio at end of period | 9.5 to 1 |  |
Risk to capital ratio | 9.5 |  |
Amount of policyholders position above or below required MPP | $ 3,400,000,000 |  |
Amount of required MPP | 1,900,000,000 |  |
Increase in contingency reserve | 534,000,000 |  |
Statutory net income | 290,000,000 |  |
Statutory policyholders' surplus | $ 1,217,000,000 |  |

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- Definition The amount by which the entity's policyholders position (the insurer's net worth or surplus, contingency reserve and a portion of the reserves for unearned premiums) was above or below the required regulatory minimum of the entity's domiciliary state. + References No definition available. + Details
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- Definition The amount of minimum policyholder position (MPP) required by the entity's domiciliary state. + References No definition available. + Details
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- Definition The number of jurisdictions that require a mortgage insurer to maintain a minimum amount of statutory capital relative to the risk in force (or a similar measure) in order for the mortgage insurer to continue to write new business. This is generally referred to as a risk-to-capital requirement. + References No definition available. + Details
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- Definition The percentage of statutory policyholders' surplus, as defined, as of the preceding calendar year end which is used in the determination of the maximum allowable dividends that the insurance subsidiaries may pay in any twelve-month period without regulatory approval by the Office of the Commissioner of Insurance of the State of Wisconsin. + References No definition available. + Details
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- Definition The entity's risk-to-capital ratio as of the end of the reporting period. + References No definition available. + Details
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- Definition The risk-to-capital ratio of the entity's combined insurance operations as of the end of the reporting period. + References No definition available. + Details
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- Definition Statutory Accounting Practices, Statutory Amount Available For Dividend Payments Without Regulatory Approval, Measurement, Measurement Period + References No definition available. + Details
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- Definition Statutory Accounting Practices, Statutory Amount Available for Dividend Payments without Regulatory Approval, Measurement, Dividend Payment Period + References No definition available. + Details
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- Definition Statutory Capital Requirements, Risk To Capital Ratio + References No definition available. + Details
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- Definition Statutory Capital Requirements, Risk To Capital Ratio For Combined Insurance Operations + References No definition available. + Details
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- Definition For insurance companies, a description of the minimum regulatory capital requirements imposed by state insurance regulators, and restrictions on dividend payments. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 505 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6486098&loc=d3e24708-158529 + Details
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- Definition Amount as of the balance sheet date of each item listed to reconcile the differences resulting from applying state prescribed statutory accounting practices rather than statutory accounting practices prescribed by National Association of Insurance Commissioners. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 505 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6486098&loc=d3e24746-158529 + Details
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- Definition The amount of statutory capital and surplus (stockholders' equity) as of the balance sheet date using prescribed or permitted statutory accounting practices (rather than GAAP, if different) of the state or country. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(23)(c)) -URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6486098&loc=d3e24708-158529 + Details
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- Definition Amount of net income for the period determined using accounting principles prescribed or permitted by insurance regulators. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(23)(c)) -URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910 + Details
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