Reinsurance - Excess-of-Loss Program (Details) - USD ($) $ in Thousands	1 Months Ended							6 Months Ended	12 Months Ended
	Mar. 31, 2022	Nov. 30, 2021	Apr. 30, 2021	Oct. 31, 2020	Feb. 29, 2020	Apr. 30, 2019	Nov. 30, 2018	Jun. 30, 2022	Dec. 31, 2021
Total fixed-maturities available for sale								$ 5,228,744	$ 5,517,078
Mortgage
RIF								63,800,000	60,900,000
Excess-of-Loss Program | Radian Guaranty | Eagle Re 2021-2 Ltd. | Mortgage
RIF		$ 10,758,000						9,714,000	10,379,000
Initial and remaining coverage		484,000						484,000	484,000
Excess-of-Loss Program | Radian Guaranty | Eagle Re 2021-2 Ltd. | First Layer Retention | Mortgage
Initial first layer retention		$ 242,000						242,000	242,000
Excess-of-Loss Program | Radian Guaranty | Eagle Re 2021-1 Ltd. | Mortgage
RIF			$ 11,061,000					8,633,000	9,496,000
Initial and remaining coverage			498,000					432,000	498,000
Excess-of-Loss Program | Radian Guaranty | Eagle Re 2021-1 Ltd. | Radian Group Inc.
Proceeds from issuance of debt								45,400
Excess-of-Loss Program | Radian Guaranty | Eagle Re 2021-1 Ltd. | First Layer Retention | Mortgage
Initial first layer retention			$ 221,000					221,000	221,000
Excess-of-Loss Program | Radian Guaranty | Eagle Re 2020-2 Ltd. | Mortgage
RIF				$ 13,011,000				6,571,000	7,623,000
Initial and remaining coverage				390,000				66,000	144,000
Excess-of-Loss Program | Radian Guaranty | Eagle Re 2020-2 Ltd. | Radian Group Inc.
Proceeds from issuance of debt	$ 17,500
Total fixed-maturities available for sale								8,300
Excess-of-Loss Program | Radian Guaranty | Eagle Re 2020-2 Ltd. | First Layer Retention | Mortgage
Initial first layer retention				$ 423,000				423,000	423,000
Excess-of-Loss Program | Radian Guaranty | Eagle Re 2020-1 Ltd. | Mortgage
RIF					$ 9,866,000			2,675,000	3,241,000
Initial and remaining coverage					488,000			434,000	488,000
Excess-of-Loss Program | Radian Guaranty | Eagle Re 2020-1 Ltd. | First Layer Retention | Mortgage
Initial first layer retention					$ 202,000			202,000	202,000
Excess-of-Loss Program | Radian Guaranty | Eagle Re 2019-1 Ltd. | Mortgage
RIF						$ 10,705,000		1,977,000	2,429,000
Initial and remaining coverage						562,000		385,000	385,000
Excess-of-Loss Program | Radian Guaranty | Eagle Re 2019-1 Ltd. | First Layer Retention | Mortgage
Initial first layer retention						$ 268,000		264,000	264,000
Excess-of-Loss Program | Radian Guaranty | Eagle Re 2018-1 Ltd. | Mortgage
RIF							$ 9,109,000	1,717,000	2,117,000
Initial and remaining coverage							434,000	276,000	276,000
Excess-of-Loss Program | Radian Guaranty | Eagle Re 2018-1 Ltd. | First Layer Retention | Mortgage
Initial first layer retention							$ 205,000	$ 201,000	$ 201,000