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Reinsurance - Narrative (Details) - USD ($) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2020 | Mar. 31, 2019 | Dec. 31, 2021
Effects of Reinsurance [Line Items] |  |  |
Ceded premiums | $ 31,576,000 | $ 30,724,000 |
Quota Share Reinsurance Agreement, 2020 |  |  |
Effects of Reinsurance [Line Items] |  |  |
Contingent termination fee | $ 0 |  |
Threshold for private mortgage insurer eligibility requirements for termination election (less than) (as a percent) | 90.00% |  |
Quota share for all policies covered (as a percent) | 30.00% |  |
Cede rate, option 1 (as a percent) | 25.00% |  |
Cede rate, option 2 (as a percent) | 20.00% |  |
Ceding commission, percentage (as a percent) | 20.00% |  |
Loss ratio threshold for profit commissions (as a percent) | 62.00% |  |
Quota Share Reinsurance Agreements, Excluding Captive Agreements |  |  |
Effects of Reinsurance [Line Items] |  |  |
Annual loss ratio cap under quota share reinsurance transactions (as a percent) | 300.00% |  |
Lifetime loss ratio cap under quota share reinsurance transactions (as a percent) | 200.00% |  |
Excess of Loss Reinsurance Agreement, Home Re |  |  |
Effects of Reinsurance [Line Items] |  |  |
Ceded premiums | $ 4,700,000 | $ 2,500,000 |
Forecast | Quota Share Reinsurance Agreement, 2021 |  |  |
Effects of Reinsurance [Line Items] |  |  |
Contingent termination fee |  |  | $ 0
Threshold for private mortgage insurer eligibility requirements for termination election (less than) (as a percent) |  |  | 90.00%
Quota share for all policies covered (as a percent) |  |  | 17.50%
Cede rate, option 1 (as a percent) |  |  | 14.50%
Cede rate, option 2 (as a percent) |  |  | 12.00%
Loss ratio threshold for profit commissions (as a percent) |  |  | 62.00%

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- Definition The annual maximum ratio of non-life losses and loss expenses to non-life net premiums earned under our quota share reinsurance transactions. + References No definition available. + Details
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- Definition The lifetime maximum ratio of non-life losses and loss expenses to non-life net premiums earned under our quota share reinsurance transactions. + References No definition available. + Details
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- Definition Reinsurance, Quota Share Reinsurance Agreement, Terms, Ceding Commission, Percent + References No definition available. + Details
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- Definition Reinsurance, Quota Share Reinsurance Agreement, Terms, Quota Share, Percent + References No definition available. + Details
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- Definition Reinsurance, Quota Share Reinsurance Agreement, Terms, Threshold For Private Mortgage Insurer Eligibility Requirements For Termination Election + References No definition available. + Details
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- Definition Amount of earned premiums ceded to other entities. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 235 -Section S99 -Paragraph 2 -Subparagraph (SX 210.12-17(Column C)) -URI http://asc.fasb.org/extlink&oid=34713774&loc=d3e574992-122915 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(1)) -URI http://asc.fasb.org/extlink&oid=116637232&loc=SL114874131-224263 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 605 -Section 50 -Paragraph 1 -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=6486672&loc=d3e27261-158547 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 605 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=84167274&loc=d3e27175-158546 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 605 -Section 50 -Paragraph 1 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=6486672&loc=d3e27261-158547 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 605 -Section 50 -Paragraph 1 -Subparagraph (b)(3) -URI http://asc.fasb.org/extlink&oid=6486672&loc=d3e27261-158547 + Details
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