Deposits (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Deposits, by Type [Abstract]
Non-interest bearing demand	$ 7,560,000	$ 5,568,300
Interest bearing:
Demand	7,205,900	4,753,200
Savings	8,379,300	4,981,600
Total	438,000	186,700
Time, other	1,490,400	779,800
Total interest bearing	17,513,600	10,701,300
Total deposits	25,073,600	16,269,600
Brokered time deposits	0
Time deposits obtained through Certificate of Deposit Account Registry Service (CDARS)	36,600	104,500
Time deposits of $250,000 or more	438,000	186,700
FDIC deposit insurance limit	250,000
Time, $250 and Over
Due within 3 months or less	47,800
Due after 3 months and within 6 months	34,600
Due after 6 months and within 12 months	283,900
Due within 2024	55,000
Due within 2025	10,700
Due within 2026	4,800
Due within 2027 and thereafter	1,200
Total	438,000	186,700
Total Time
Due within 3 months or less	311,800
Due after 3 months and within 6 months	215,400
Due after 6 months and within 12 months	1,005,400
Due within 2024	282,800
Due within 2025	69,200
Due within 2026	27,800
Due within 2027 and thereafter	16,000
Total	1,928,400
Interest expense, time deposits, $100,000 or more	$ 2,500	$ 900	$ 2,700