Investments - Available for Sale Securities (Details) - USD ($) $ in Thousands		Jun. 30, 2025		Dec. 31, 2024
Debt Securities, Available-for-sale [Line Items]
Less: loaned securities		$ 179,692		$ 139,121
Total fixed-maturities, available for sale, Amortized Cost		5,449,992		5,511,501
Total fixed-maturities available for sale, Fair Value		5,108,278		5,074,920
Total fixed-maturities available for sale
Debt Securities, Available-for-sale [Line Items]
Amortized Cost		5,584,431		5,648,583
Total fixed-maturities, available for sale, Amortized Cost		5,449,992		5,511,501	[1]
Gross Unrealized Gains		32,599		16,565
Gross Unrealized Losses	[2]	(378,625)		(460,376)
Fair Value		5,238,405		5,204,772
Total fixed-maturities available for sale, Fair Value		5,108,278		5,074,920	[1]
U.S. government and agency securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost		164,513		160,509
Gross Unrealized Gains		126		0
Gross Unrealized Losses		(29,270)		(32,177)
Fair Value		135,369		128,332
State and municipal obligations
Debt Securities, Available-for-sale [Line Items]
Amortized Cost		159,695		167,114
Gross Unrealized Gains		167		40
Gross Unrealized Losses		(16,375)		(18,263)
Fair Value		143,487		148,891
Corporate bonds and notes
Debt Securities, Available-for-sale [Line Items]
Amortized Cost		2,767,925		2,878,705
Gross Unrealized Gains		17,288		5,261
Gross Unrealized Losses		(230,241)		(277,535)
Fair Value		2,554,972		2,606,431
RMBS
Debt Securities, Available-for-sale [Line Items]
Amortized Cost		1,063,500		1,104,721
Gross Unrealized Gains		8,628		6,965
Gross Unrealized Losses		(80,619)		(100,056)
Fair Value		991,509		1,011,630
CMBS
Debt Securities, Available-for-sale [Line Items]
Amortized Cost		343,420		438,139
Gross Unrealized Gains		37		51
Gross Unrealized Losses		(18,073)		(26,191)
Fair Value		325,384		411,999
CLO
Debt Securities, Available-for-sale [Line Items]
Amortized Cost		480,161		411,328
Gross Unrealized Gains		862		983
Gross Unrealized Losses		(580)		(849)
Fair Value		480,443		411,462
Other ABS
Debt Securities, Available-for-sale [Line Items]
Amortized Cost		559,833		442,620
Gross Unrealized Gains		4,055		1,556
Gross Unrealized Losses		(3,467)		(5,305)
Fair Value		560,421		438,871
Mortgage insurance-linked notes
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	[3]	45,384		45,447
Gross Unrealized Gains	[3]	1,436		1,709
Gross Unrealized Losses	[3]	0		0
Fair Value	[3]	46,820		47,156
Loaned securities, amortized cost | Total fixed-maturities available for sale
Debt Securities, Available-for-sale [Line Items]
Less: loaned securities		134,439	[1]	137,082
Loaned securities, fair value | Total fixed-maturities available for sale
Debt Securities, Available-for-sale [Line Items]
Less: loaned securities		$ 130,127	[1]	$ 129,852

[1] Included in other assets on our condensed consolidated balance sheets. See “Loaned Securities” below for a discussion of our securities lending agreements.

[2] See “Gross Unrealized Losses and Related Fair Value of Available for Sale Securities” below for additional details.

[3] Includes mortgage insurance-linked notes purchased by Radian Group in connection with the XOL Program. See Note 8 for more information.