Deposit Accounts - Deposit Accounts and Weighted Average Interest Rates (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Transaction accounts
Noninterest-bearing checking	$ 4,932,817	$ 6,306,825
Interest-bearing checking	2,899,621	3,119,850
Money market	4,572,693	4,946,019
Savings	295,749	476,588
Total transaction accounts	12,700,880	14,849,282
Time deposit accounts
$250,000 or less	853,013	525,299
Greater than $250,000	1,441,733	1,977,820
Total time deposit accounts	2,294,746	2,503,119
Total deposits	$ 14,995,626	$ 17,352,401
Total transaction accounts
Noninterest-bearing checking (as a percent)	32.90%	36.40%
Interest-bearing checking (as a percent)	19.30%	18.00%
Money market (as a percent)	30.50%	28.50%
Savings (as a percent)	2.00%	2.70%
Total transaction accounts (as a percent)	84.70%	85.60%
Total time deposit accounts
Less than $250,000 (as a percent)	5.70%	3.00%
Greater than $250,000 (as a percent)	9.60%	11.40%
Total time deposit accounts (as a percent)	15.30%	14.40%
Total deposits (as a percent)	100.00%	100.00%
Transaction accounts
Noninterest-bearing checking (as a percent)	0.00%	0.00%
Interest-bearing checking (as a percent)	1.38%	0.63%
Money market (as a percent)	2.00%	0.85%
Savings (as a percent)	0.29%	0.49%
Total transaction accounts (as a percent)	1.04%	0.43%
Time deposit accounts
Less than $250,000 (as a percent)	4.04%	1.35%
Greater than $250,000 (as a percent)	4.56%	3.37%
Total time deposit accounts (as a percent)	4.37%	2.95%
Total deposits (as a percent)	1.55%	0.79%