Losses and LAE - Schedule of Cumulative Paid Claims / Reconciliation of Outstanding Liabilities (Details) - USD ($) $ in Thousands		Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Mortgage insurance
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability [Line Items]
Cumulative paid claims, net of reinsurance		$ 429,208
Mortgage insurance
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability [Line Items]
Liabilities for claims, net of reinsurance		339,391
Mortgage insurance | Mortgage insurance
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability [Line Items]
Liabilities for claims, net of reinsurance	[1]	339,391
2016 | Mortgage insurance
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability [Line Items]
Cumulative paid claims, net of reinsurance		140,113	$ 139,937	$ 139,651	$ 139,539	$ 138,525	$ 137,306	$ 134,115	$ 119,357	$ 76,616	$ 11,061
2017 | Mortgage insurance
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability [Line Items]
Cumulative paid claims, net of reinsurance		113,603	113,497	113,027	112,445	111,458	108,484	99,678	66,585	$ 24,653
2018 | Mortgage insurance
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability [Line Items]
Cumulative paid claims, net of reinsurance		64,256	64,015	63,603	62,968	60,926	54,625	36,066	$ 5,584
2019 | Mortgage insurance
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability [Line Items]
Cumulative paid claims, net of reinsurance		39,426	39,082	37,960	35,594	28,896	18,703	$ 4,220
2020 | Mortgage insurance
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability [Line Items]
Cumulative paid claims, net of reinsurance		20,375	19,465	17,884	14,635	9,867	$ 4,148
2021 | Mortgage insurance
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability [Line Items]
Cumulative paid claims, net of reinsurance		6,696	6,043	4,409	2,561	$ 1,112
2022 | Mortgage insurance
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability [Line Items]
Cumulative paid claims, net of reinsurance		9,238	6,699	2,867	$ 498
2023 | Mortgage insurance
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability [Line Items]
Cumulative paid claims, net of reinsurance		17,996	6,201	$ 246
2024 | Mortgage insurance
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability [Line Items]
Cumulative paid claims, net of reinsurance		15,740	$ 1,118
2025 | Mortgage insurance
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability [Line Items]
Cumulative paid claims, net of reinsurance		1,765
All outstanding liabilities before 2016, net of reinsurance
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability [Line Items]
Cumulative paid claims, net of reinsurance		6,634
All outstanding liabilities before 2016, net of reinsurance | Mortgage insurance
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability [Line Items]
Cumulative paid claims, net of reinsurance		$ 6,634

[1] Calculated as follows:   (In thousands)       Incurred losses, net of reinsurance   $ 761,965   All outstanding liabilities before 2016, net of reinsurance     6,634   Cumulative paid claims, net of reinsurance     (429,208 ) Liabilities for claims, net of reinsurance   $ 339,391