Employee Benefits - Components of Net Periodic Benefit Cost (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Components of net periodic benefit cost:
Service cost	$ 24,474	$ 31,382	$ 31,660
Interest cost	17,559	10,582	5,694
Expected return on plan assets	(30,127)	(35,486)	(33,333)
Past service credit	(11,560)	(11,882)	(11,796)
Recognized net actuarial loss	9,563	11,032	13,400
Curtailment	(15,908)	0	0
Settlement	0	12,045	0
Net periodic benefit cost	(5,999)	17,673	5,625
Discontinued Operations, Held-for-Sale | Insurance Agency Business
Components of net periodic benefit cost:
Service cost	$ 5,100	$ 7,500	$ 7,700