Investment Securities - Schedule of Debt and Equity Securities (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2025	Dec. 31, 2024
Cost
Equity	$ 410,316	$ 259,554
Debt	855,540	864,575
Other	10,324	155,802
Total	1,276,180	1,279,931
Gross Unrealized Gain
Equity	217,254	231,815
Debt	5,535	3,209
Other	401	224
Total	223,190	235,248
Gross Unrealized Loss
Equity	(5,760)	(6,385)
Debt	(11,816)	(17,336)
Other	(358)	(96)
Total	(17,934)	(23,817)
Fair Value
Equity	621,810	484,984
Debt	849,259	850,448
Other	10,367	155,930
Total	$ 1,481,436	$ 1,491,362

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