Investments - Schedule of Unrealized Loss on Investments (Details) - USD ($) $ in Thousands	Mar. 31, 2025	Dec. 31, 2024
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 219,403	$ 461,425
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	2,160	7,105
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	1,148,628	1,179,267
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	149,335	157,295
Debt Securities, Available-for-sale, Unrealized Loss Position	1,368,031	1,640,692
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	151,495	164,400
Obligations of U.S. Government-sponsored enterprises
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	1,996	21,044
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	5	132
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	229,941	234,191
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	11,410	14,226
Debt Securities, Available-for-sale, Unrealized Loss Position	231,937	255,235
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	11,415	14,358
Obligations of states and political subdivisions
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	4,847	3,117
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	208	143
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	398,477	403,767
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	88,208	83,568
Debt Securities, Available-for-sale, Unrealized Loss Position	403,324	406,884
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	88,416	83,711
Agency mortgage-backed securities
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	176,976	423,600
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	1,910	6,763
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	468,526	478,790
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	48,275	57,410
Debt Securities, Available-for-sale, Unrealized Loss Position	645,502	902,390
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	50,185	64,173
U.S. Treasury bills
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	1,984	1,956
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	16	44
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	6,486	8,342
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	264	408
Debt Securities, Available-for-sale, Unrealized Loss Position	8,470	10,298
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	280	452
Corporate debt securities
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	33,600	11,708
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	21	23
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	45,198	54,177
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	1,178	1,683
Debt Securities, Available-for-sale, Unrealized Loss Position	78,798	65,885
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	$ 1,199	$ 1,706