Contingencies and Commitments - Narrative (Details) - USD ($) $ in Thousands		12 Months Ended
	Oct. 05, 2023	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Jun. 14, 2023
Loss Contingencies [Line Items]
Loss contingency, estimate	$ 109,960	$ 190,000			$ 117,750
Loss contingency, insurance rate freeze, term	5 years
Loss contingency, percentage of policyholder claim amounts	0.14%
Loss contingency, objection or opt out, period	45 days
Operating lease ROU asset		118,000	$ 140,000
Present value of minimum lease payments		$ 129,000	$ 152,000
Weighted average discount rate, operating lease		4.40%	3.30%
Weighted average remaining operating lease term		4 years	5 years
Operating lease expense		$ 42,000	$ 45,000	$ 49,000
Finance lease, net book value		5,000	14,000
Present value of minimum lease payments		27,000	106,000
Finance lease, right-of-use asset, accumulated amortization		$ 467,000	$ 458,000
Weighted average discount rate, finance lease		6.40%	2.90%
Weighted average remaining finance lease term		2 years	1 year
Payables (recoveries) for congressionally mandated assessments		$ 1,000	$ (2,000)
Certain Financing Arrangments
Loss Contingencies [Line Items]
Present value of minimum lease payments		$ 595,000	$ 558,000