Reinsurance - Excess of Loss Reinsurance (Details) - USD ($) $ in Thousands									6 Months Ended	12 Months Ended
	Apr. 01, 2023	Apr. 26, 2022	Apr. 01, 2022	Aug. 03, 2021	Feb. 02, 2021	Oct. 29, 2020	May 25, 2019	Oct. 30, 2018	Jun. 30, 2023	Dec. 31, 2022
2023 Traditional XOL
Effects of Reinsurance [Line Items]
Amortization period excess of loss reinsurance coverage	10 years
Excess of loss reinsurance coverage, initial and remaining	$ 116,000
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									$ 82,490	$ 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									325,317	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									189,894	190,097
Excess of loss reinsurance coverage, initial and remaining				$ 398,429					299,100	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									210,961	211,102
Excess of loss reinsurance coverage, initial and remaining					$ 398,848				229,325	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									274,978	275,051
Excess of loss reinsurance coverage, initial and remaining						$ 412,917			72,127	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									183,000	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									164,572	164,849
Excess of loss reinsurance coverage, initial and remaining								$ 318,636	$ 102,557	$ 140,993