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Reinsurance - Excess of Loss Reinsurance (Details) - USD ($) $ in Thousands |  |  |  |  |  |  |  | 3 Months Ended | 12 Months Ended
--- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Apr. 26, 2022 | Apr. 01, 2022 | Aug. 03, 2021 | Feb. 02, 2021 | Oct. 29, 2020 | May 25, 2019 | Oct. 30, 2018 | Mar. 31, 2023 | Dec. 31, 2022
2022 Traditional XOL |  |  |  |  |  |  |  |  |
Effects of Reinsurance [Line Items] |  |  |  |  |  |  |  |  |
Amortization period excess of loss reinsurance coverage |  | 10 years |  |  |  |  |  |  |
Initial first layer retention |  | $ 82,523 |  |  |  |  |  |  |
Remaining first layer retention |  |  |  |  |  |  |  | $ 82,509 | $ 82,517
Excess of loss reinsurance coverage, initial and remaining |  | $ 142,642 |  |  |  |  |  | 142,642 | 142,642
Home Re 2022-1 |  |  |  |  |  |  |  |  |
Effects of Reinsurance [Line Items] |  |  |  |  |  |  |  |  |
Term of mortgage insurance-linked notes | 12 years 6 months |  |  |  |  |  |  |  |
Initial first layer retention | $ 325,589 |  |  |  |  |  |  |  |
Remaining first layer retention |  |  |  |  |  |  |  | 325,520 | 325,576
Excess of loss reinsurance coverage, initial and remaining | $ 473,575 |  |  |  |  |  |  | 473,575 | 473,575
Home Re 2021-2 |  |  |  |  |  |  |  |  |
Effects of Reinsurance [Line Items] |  |  |  |  |  |  |  |  |
Term of mortgage insurance-linked notes |  |  | 12 years 6 months |  |  |  |  |  |
Initial first layer retention |  |  | $ 190,159 |  |  |  |  |  |
Remaining first layer retention |  |  |  |  |  |  |  | 190,016 | 190,097
Excess of loss reinsurance coverage, initial and remaining |  |  | $ 398,429 |  |  |  |  | 327,346 | 352,084
Home Re 2021-1 |  |  |  |  |  |  |  |  |
Effects of Reinsurance [Line Items] |  |  |  |  |  |  |  |  |
Term of mortgage insurance-linked notes |  |  |  | 12 years 6 months |  |  |  |  |
Initial first layer retention |  |  |  | $ 211,159 |  |  |  |  |
Remaining first layer retention |  |  |  |  |  |  |  | 211,055 | 211,102
Excess of loss reinsurance coverage, initial and remaining |  |  |  | $ 398,848 |  |  |  | 251,942 | 277,053
Home Re 2020-1 |  |  |  |  |  |  |  |  |
Effects of Reinsurance [Line Items] |  |  |  |  |  |  |  |  |
Term of mortgage insurance-linked notes |  |  |  |  | 10 years |  |  |  |
Initial first layer retention |  |  |  |  | $ 275,283 |  |  |  |
Remaining first layer retention |  |  |  |  |  |  |  | 274,979 | 274,871
Excess of loss reinsurance coverage, initial and remaining |  |  |  |  | $ 412,917 |  |  | 92,648 | 113,247
Home Re 2019-1 |  |  |  |  |  |  |  |  |
Effects of Reinsurance [Line Items] |  |  |  |  |  |  |  |  |
Term of mortgage insurance-linked notes |  |  |  |  |  | 10 years |  |  |
Initial first layer retention |  |  |  |  |  | $ 185,730 |  |  |
Remaining first layer retention |  |  |  |  |  |  |  | 183,351 | 183,540
Excess of loss reinsurance coverage, initial and remaining |  |  |  |  |  | $ 315,739 |  | 208,146 | 208,146
Home Re 2018-1 |  |  |  |  |  |  |  |  |
Effects of Reinsurance [Line Items] |  |  |  |  |  |  |  |  |
Term of mortgage insurance-linked notes |  |  |  |  |  |  | 10 years |  |
Initial first layer retention |  |  |  |  |  |  | $ 168,691 |  |
Remaining first layer retention |  |  |  |  |  |  |  | 164,708 | 164,849
Excess of loss reinsurance coverage, initial and remaining |  |  |  |  |  |  | $ 318,636 | $ 121,513 | $ 140,993

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- Definition Amount per life of risk undertaken originally by insurer that is not ceded to reinsurer. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 20 -Section 50 -Paragraph 3 -URI https://asc.fasb.org/extlink&oid=99397103&loc=d3e6811-158387 + Details
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