Policyholders' Liabilities - Schedule of Liability for Future Policy Benefits (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023	Dec. 31, 2022
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]
Net liability for future policy benefits	$ 1,237,871	$ 1,148,478	$ 1,230,142
Life Insurance:
Liability for Future Policy Benefit, Expected Net Premium [Roll Forward]
Balance, beginning of year	258,177	245,437
Beginning balance at original discount rate	265,959	258,283
Effect of changes in cash flow assumptions			18,005	$ (172)
Effect of actual variances from expected experience			(11,230)	5,215
Adjusted beginning of year balance			272,734	263,326
Issuances	76,675	23,526
Interest accrual	8,722	7,145
Net premiums collected	(38,486)	(33,484)
Derecognition and other	(5,438)	807
Ending balance at original discount rate	314,207	261,320
AOCI, Liability for Future Policy Benefit, Expected Net Premium, before Tax	(1,346)	(16,881)
Balance, end of period	312,861	244,439
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]
Pre-adoption liability, beginning balance	1,168,472	1,143,027
Beginning balance at original discount rate	1,198,717	1,204,220
Effect of changes in cash flow assumptions			19,054	(1,091)
Effect of actual variances from expected experience			(6,740)	9,827
Adjusted beginning of year balance			1,211,031	1,212,956
Issuances	77,484	24,158
Interest accrual	39,809	38,758
Benefit payments	(80,722)	(79,943)
Derecognition and other	(6,626)	139
Ending balance at original discount rate	1,240,976	1,196,068
Effect of changes in discount rates	(14,462)	(96,850)
Post-adoption liability, ending balance	1,226,514	1,099,218
Net liability for future policy benefits	913,653	854,779
Less: Reinsurance recoverable	1,308
Net liability for future policy benefits, after reinsurance recoverable	912,345
Home Service Insurance:
Liability for Future Policy Benefit, Expected Net Premium [Roll Forward]
Balance, beginning of year	113,757	106,763
Beginning balance at original discount rate	117,557	114,619
Effect of changes in cash flow assumptions			(441)	(258)
Effect of actual variances from expected experience			(9,310)	(10,108)
Adjusted beginning of year balance			107,806	104,253
Issuances	13,265	16,961
Interest accrual	3,587	3,367
Net premiums collected	(8,224)	(6,890)
Derecognition and other	374	588
Ending balance at original discount rate	116,808	118,279
AOCI, Liability for Future Policy Benefit, Expected Net Premium, before Tax	(2,367)	(10,835)
Balance, end of period	114,441	107,444
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]
Pre-adoption liability, beginning balance	334,730	316,707
Beginning balance at original discount rate	341,465	336,096
Effect of changes in cash flow assumptions			(1,580)	74
Effect of actual variances from expected experience			(7,572)	(6,809)
Adjusted beginning of year balance			332,313	329,361
Issuances	13,265	16,969
Interest accrual	11,538	11,229
Benefit payments	(15,685)	(16,953)
Derecognition and other	352	573
Ending balance at original discount rate	341,783	341,179
Effect of changes in discount rates	(8,290)	(36,604)
Post-adoption liability, ending balance	333,493	304,575
Net liability for future policy benefits	219,052	197,131
Less: Reinsurance recoverable	0
Net liability for future policy benefits, after reinsurance recoverable	219,052
Permanent | Life Insurance:
Liability for Future Policy Benefit, Expected Net Premium [Roll Forward]
Balance, beginning of year	244,917	235,228
Beginning balance at original discount rate	252,426	247,601
Effect of changes in cash flow assumptions			17,731	(210)
Effect of actual variances from expected experience			(12,203)	4,156
Adjusted beginning of year balance			257,954	251,547
Issuances	74,426	20,918
Interest accrual	8,342	6,897
Net premiums collected	(36,066)	(31,480)
Derecognition and other	(5,530)	567
Ending balance at original discount rate	299,126	248,449
AOCI, Liability for Future Policy Benefit, Expected Net Premium, before Tax	(1,303)	(16,380)
Balance, end of period	297,823	232,069
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]
Pre-adoption liability, beginning balance	973,350	947,415
Beginning balance at original discount rate	995,962	996,169
Effect of changes in cash flow assumptions			18,320	(389)
Effect of actual variances from expected experience			(9,656)	6,338
Adjusted beginning of year balance			1,004,626	1,002,118
Issuances	75,132	21,360
Interest accrual	33,624	32,470
Benefit payments	(67,441)	(63,211)
Derecognition and other	(6,642)	97
Ending balance at original discount rate	1,039,299	992,834
Effect of changes in discount rates	(8,395)	(78,072)
Post-adoption liability, ending balance	1,030,904	914,762
Net liability for future policy benefits	733,081	682,693
Less: Reinsurance recoverable	1,308
Net liability for future policy benefits, after reinsurance recoverable	731,773
Permanent | Home Service Insurance:
Liability for Future Policy Benefit, Expected Net Premium [Roll Forward]
Balance, beginning of year	98,831	93,508
Beginning balance at original discount rate	102,045	100,225
Effect of changes in cash flow assumptions			(462)	(343)
Effect of actual variances from expected experience			(5,784)	(5,631)
Adjusted beginning of year balance			95,799	94,251
Issuances	11,412	13,854
Interest accrual	3,193	3,019
Net premiums collected	(9,116)	(8,909)
Derecognition and other	317	475
Ending balance at original discount rate	101,605	102,690
AOCI, Liability for Future Policy Benefit, Expected Net Premium, before Tax	(2,042)	(9,438)
Balance, end of period	99,563	93,252
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]
Pre-adoption liability, beginning balance	211,946	200,351
Beginning balance at original discount rate	217,524	214,188
Effect of changes in cash flow assumptions			(502)	(257)
Effect of actual variances from expected experience			(5,880)	(5,472)
Adjusted beginning of year balance			211,142	208,459
Issuances	11,407	13,854
Interest accrual	7,233	6,987
Benefit payments	(11,399)	(12,246)
Derecognition and other	301	464
Ending balance at original discount rate	218,684	217,518
Effect of changes in discount rates	(5,797)	(23,934)
Post-adoption liability, ending balance	212,887	193,584
Net liability for future policy benefits	113,324	100,332
Less: Reinsurance recoverable	0
Net liability for future policy benefits, after reinsurance recoverable	113,324
Permanent Limited Pay | Life Insurance:
Liability for Future Policy Benefit, Expected Net Premium [Roll Forward]
Balance, beginning of year	13,260	10,209
Beginning balance at original discount rate	13,533	10,682
Effect of changes in cash flow assumptions			274	38
Effect of actual variances from expected experience			973	1,059
Adjusted beginning of year balance			14,780	11,779
Issuances	2,249	2,608
Interest accrual	380	248
Net premiums collected	(2,420)	(2,004)
Derecognition and other	92	240
Ending balance at original discount rate	15,081	12,871
AOCI, Liability for Future Policy Benefit, Expected Net Premium, before Tax	(43)	(501)
Balance, end of period	15,038	12,370
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]
Pre-adoption liability, beginning balance	195,122	195,612
Beginning balance at original discount rate	202,755	208,051
Effect of changes in cash flow assumptions			734	(702)
Effect of actual variances from expected experience			2,916	3,489
Adjusted beginning of year balance			206,405	210,838
Issuances	2,352	2,798
Interest accrual	6,185	6,288
Benefit payments	(13,281)	(16,732)
Derecognition and other	16	42
Ending balance at original discount rate	201,677	203,234
Effect of changes in discount rates	(6,067)	(18,778)
Post-adoption liability, ending balance	195,610	184,456
Net liability for future policy benefits	180,572	172,086
Less: Reinsurance recoverable	0
Net liability for future policy benefits, after reinsurance recoverable	180,572
Permanent Limited Pay | Home Service Insurance:
Liability for Future Policy Benefit, Expected Net Premium [Roll Forward]
Balance, beginning of year	14,926	13,255
Beginning balance at original discount rate	15,512	14,394
Effect of changes in cash flow assumptions			21	85
Effect of actual variances from expected experience			(3,526)	(4,477)
Adjusted beginning of year balance			12,007	10,002
Issuances	1,853	3,107
Interest accrual	394	348
Net premiums collected	892	2,019
Derecognition and other	57	113
Ending balance at original discount rate	15,203	15,589
AOCI, Liability for Future Policy Benefit, Expected Net Premium, before Tax	(325)	(1,397)
Balance, end of period	14,878	14,192
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]
Pre-adoption liability, beginning balance	122,784	116,356
Beginning balance at original discount rate	123,941	121,908
Effect of changes in cash flow assumptions			(1,078)	331
Effect of actual variances from expected experience			(1,692)	(1,337)
Adjusted beginning of year balance			$ 121,171	$ 120,902
Issuances	1,858	3,115
Interest accrual	4,305	4,242
Benefit payments	(4,286)	(4,707)
Derecognition and other	51	109
Ending balance at original discount rate	123,099	123,661
Effect of changes in discount rates	(2,493)	(12,670)
Post-adoption liability, ending balance	120,606	110,991
Net liability for future policy benefits	105,728	$ 96,799
Less: Reinsurance recoverable	0
Net liability for future policy benefits, after reinsurance recoverable	$ 105,728