Reinsurance - Total VIE Assets and Liabilities of Eagle Re Issuers (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Ceded Credit Risk [Line Items]
Total assets	$ 7,839,185	$ 7,948,021
Total liabilities	3,580,389	3,663,668
Variable Interest Entity, Primary Beneficiary
Ceded Credit Risk [Line Items]
Total assets	2,274,548	1,539,029
Total liabilities	2,274,548	1,539,029
Eagle Re 2021-2 Ltd. | Variable Interest Entity, Primary Beneficiary | Excess-of-Loss Program | Radian Guaranty | Mortgage
Ceded Credit Risk [Line Items]
Total assets	484,122	0
Total liabilities	484,122	0
Eagle Re 2021-1 Ltd. | Variable Interest Entity, Primary Beneficiary | Excess-of-Loss Program | Radian Guaranty | Mortgage
Ceded Credit Risk [Line Items]
Total assets	497,735	0
Total liabilities	497,735	0
Eagle Re 2020-2 Ltd. | Variable Interest Entity, Primary Beneficiary | Excess-of-Loss Program | Radian Guaranty | Mortgage
Ceded Credit Risk [Line Items]
Total assets	143,986	390,324
Total liabilities	143,986	390,324
Eagle Re 2020-1 Ltd. | Variable Interest Entity, Primary Beneficiary | Excess-of-Loss Program | Radian Guaranty | Mortgage
Ceded Credit Risk [Line Items]
Total assets	488,385	488,385
Total liabilities	488,385	488,385
Eagle Re 2019-1 Ltd. | Variable Interest Entity, Primary Beneficiary | Excess-of-Loss Program | Radian Guaranty | Mortgage
Ceded Credit Risk [Line Items]
Total assets	384,602	384,602
Total liabilities	384,602	384,602
Eagle Re 2018-1 Ltd. | Variable Interest Entity, Primary Beneficiary | Excess-of-Loss Program | Radian Guaranty | Mortgage
Ceded Credit Risk [Line Items]
Total assets	275,718	275,718
Total liabilities	$ 275,718	$ 275,718