Segment Reporting - Revenue and Other Segment Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Net premiums earned	$ 981,131	$ 1,037,183	$ 1,115,321
Services revenue	92,216	125,825	105,385
Net investment income	195,658	147,909	154,037
Net gains (losses) on investments and other financial instruments	(80,733)	15,603	60,277
Other income	2,454	3,412	3,597
Total revenues	1,190,726	1,329,932	1,438,617
Interest expense	84,454	84,344	71,150
Allocation of corporate operating expenses	163,000	147,386	129,870
Other technology services
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Services revenue	3,730	3,869	3,763
Inter-segment
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Net premiums earned	0	0	0
Services revenue	(332)	(281)	(1,439)
Net investment income	0	0	0
Net gains (losses) on investments and other financial instruments	0	0	0
Other income	(170)	0	0
Total revenues	(502)	(281)	(1,439)
Adjustments
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Net premiums earned	0	0	0
Services revenue	0	0	0
Net investment income	0	0	0
Net gains (losses) on investments and other financial instruments	(80,780)	14,094	60,277
Other income	0	0	247
Total revenues	(80,780)	14,094	60,524
Mortgage
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Net premiums earned	957,213	998,282	1,092,767
Services revenue	7,390	17,670	14,765
Net investment income	171,221	132,929	137,195
Net gains (losses) on investments and other financial instruments	0	0	0
Other income	2,376	2,678	2,816
Total revenues	1,138,200	1,151,559	1,247,543
Interest expense	84,440	84,344	71,150
Direct depreciation expense	8,986	9,580	12,387
Allocation of corporate operating expenses	138,566	127,482	114,802
Mortgage | Depreciation Expense
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Allocation of corporate operating expenses	3,000	3,200	2,600
homegenius
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Net premiums earned	23,918	38,901	22,554
Services revenue	85,158	108,282	79,524
Net investment income	729	358	361
Net gains (losses) on investments and other financial instruments	0	1,509	0
Other income	170	0	0
Total revenues	109,975	149,050	102,439
Interest expense	0	0	0
Direct depreciation expense	2,538	2,452	2,857
Allocation of corporate operating expenses	22,856	18,482	12,807
homegenius | Depreciation Expense
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Allocation of corporate operating expenses	500	500	300
Reportable Segment Total | Operating Segments
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Net premiums earned	981,131	1,037,183	1,115,321
Services revenue	92,548	125,952	94,289
Net investment income	171,950	133,287	137,556
Net gains (losses) on investments and other financial instruments	0	1,509	0
Other income	2,546	2,678	2,816
Total revenues	1,248,175	1,300,609	1,349,982
Interest expense	84,440	84,344	71,150
Direct depreciation expense	11,524	12,032	15,244
Allocation of corporate operating expenses	161,422	145,964	127,609
Reportable Segment Total | Operating Segments | Depreciation Expense
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Allocation of corporate operating expenses	3,600	3,700	2,900
All Other
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Net premiums earned	0	0	0
Services revenue	0	154	12,535
Net investment income	23,708	14,622	16,481
Net gains (losses) on investments and other financial instruments	47	0	0
Other income	78	734	534
Total revenues	$ 23,833	$ 15,510	$ 29,550