Reinsurance - Excess of Loss Reinsurance (Details) $ in Thousands											6 Months Ended	12 Months Ended
	Apr. 01, 2024 USD ($)	Oct. 23, 2023 USD ($)	Apr. 01, 2023 USD ($)	Apr. 26, 2022 USD ($)	Apr. 01, 2022 USD ($)	Aug. 03, 2021 USD ($)	Feb. 02, 2021 USD ($)	Oct. 29, 2020 USD ($)	May 25, 2019 USD ($)	Oct. 30, 2018 USD ($)	Jun. 30, 2024 USD ($)	Dec. 31, 2023 USD ($)
2024 Traditional XOL
Effects of Reinsurance [Line Items]
Amortization period excess of loss reinsurance coverage	10 years
Excess of loss reinsurance coverage, initial and remaining	$ 187,000
2023 Traditional XOL
Effects of Reinsurance [Line Items]
Amortization period excess of loss reinsurance coverage			10 years
Initial first layer retention			$ 70,578
Remaining first layer retention											$ 70,544	$ 70,578
Excess of loss reinsurance coverage, initial and remaining			$ 96,942								95,034	96,942
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											81,999	82,346
Excess of loss reinsurance coverage, initial and remaining					$ 142,642						136,629	142,642
Home Re 2023-1
Effects of Reinsurance [Line Items]
Term of mortgage insurance-linked notes		10 years
Initial first layer retention		$ 272,961
Remaining first layer retention											272,850	272,961
Excess of loss reinsurance coverage, initial and remaining		$ 330,277									$ 330,277	330,277
Reinsurance Retention Policy, Funding Percentage		0.97									0.97
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											$ 323,797	325,001
Excess of loss reinsurance coverage, initial and remaining				$ 473,575							$ 368,553	420,731
Reinsurance Retention Policy, Funding Percentage				1							1
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											$ 189,007	189,403
Excess of loss reinsurance coverage, initial and remaining						$ 398,429					$ 162,140	173,960
Reinsurance Retention Policy, Funding Percentage						1					0.79
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											$ 210,376	210,831
Excess of loss reinsurance coverage, initial and remaining							$ 398,848				$ 117,564	117,982
Reinsurance Retention Policy, Funding Percentage							1				0.83
Home Re 2020-1
Effects of Reinsurance [Line Items]
Initial first layer retention								$ 275,283
Remaining first layer retention											$ 0	261,280
Excess of loss reinsurance coverage, initial and remaining								$ 412,917			$ 0	41,846
Reinsurance Retention Policy, Funding Percentage								1			0
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											$ 182,464	182,722
Excess of loss reinsurance coverage, initial and remaining									$ 315,739		$ 21,039	21,039
Reinsurance Retention Policy, Funding Percentage									1		0.10
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											$ 164,108	164,335
Excess of loss reinsurance coverage, initial and remaining										$ 318,636	$ 38,998	$ 69,762
Reinsurance Retention Policy, Funding Percentage										1	1