Reinsurance - Effect of Reinsurance Programs (Details) - USD ($)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Ceded Credit Risk [Line Items]
Direct premiums written	$ 992,418,000	$ 1,024,660,000	$ 1,108,513,000
Ceded premiums written	(12,652,000)	(48,279,000)	(87,201,000)
Total net premiums written	983,791,000	983,447,000	1,033,509,000
Direct premiums earned	1,050,029,000	1,144,361,000	1,286,527,000
Assumed premiums earned	4,025,000	7,066,000	12,214,000
Ceded premiums earned	(72,923,000)	(114,244,000)	(183,420,000)
Total net premiums earned	981,131,000	1,037,183,000	1,115,321,000
Ceding commissions earned	18,998,000	31,745,000	53,654,000
Ceded losses	(41,980,000)	(4,570,000)
Ceded losses			58,266,000
Deferred ceding commissions	27,400,000	38,600,000
Mortgage insurance
Ceded Credit Risk [Line Items]
Direct premiums written	967,996,000	984,995,000	1,085,670,000
Assumed premiums written	4,025,000	7,066,000	12,197,000
Ceded premiums written	(12,148,000)	(47,515,000)	(86,912,000)
Direct premiums earned	1,025,607,000	1,104,696,000	1,263,684,000
Assumed premiums earned	4,025,000	7,066,000	12,214,000
Ceded premiums earned	(72,419,000)	(113,480,000)	(183,131,000)
Total net premiums earned	957,213,000	998,282,000	1,092,767,000
Title insurance
Ceded Credit Risk [Line Items]
Direct premiums written	24,422,000	39,665,000	22,843,000
Ceded premiums written	(504,000)	(764,000)	(289,000)
Direct premiums earned	24,422,000	39,665,000	22,843,000
Ceded premiums earned	$ (504,000)	$ (764,000)	$ (289,000)