CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024
Operating activities
Net income	$ 304,540	$ 289,931
Adjustments to reconcile net income to net cash used in operating activities:
Provisions for credit losses	23,286	12,041
Income tax expense	98,579	97,554
Amortization of brokered deposit placement fee	2,213	2,803
Amortization of Secured Borrowing Facility upfront fee	584	713
Amortization of deferred loan origination costs and loan premium/(discounts), net	3,806	3,229
Net amortization of discount on investments	(327)	(601)
Depreciation of premises and equipment	3,953	4,705
Acquired intangible assets amortization expense	1,021	1,215
Stock-based compensation expense	13,272	13,790
Unrealized (gains) losses on derivatives and hedging activities, net	(6)	20
Gains on sales of loans, net	(187,735)	(143,039)
(Gains) losses on securities, net	10,378	(2,118)
Other adjustments to net income, net	4,093	2,939
Changes in operating assets and liabilities:
Increase in accrued interest receivable	(296,543)	(287,000)
Increase in trading investments	(812)	0
Increase in non-marketable securities	0	(283)
Decrease in other interest-earning assets	1,497	1,657
Increase in other assets	(46,659)	(23,046)
Decrease in income taxes payable, net	(11,493)	(6,463)
Decrease in accrued interest payable	(26,984)	(15,738)
Decrease in other liabilities	(42,714)	(29,020)
Total adjustments	(450,591)	(366,642)
Total net cash used in operating activities	(146,051)	(76,711)
Investing activities
Loans acquired and originated	(2,783,336)	(2,593,293)
Net proceeds from sales of loans held for investment and loans held for sale	2,208,600	2,149,774
Proceeds from FFELP Loan claim payments	0	10,819
Net decrease in loans held for investment and loans held for sale (other than loans acquired and originated, and loan sales)	774,483	751,120
Purchases of available-for-sale securities	(38,174)	(25,790)
Proceeds from sales and maturities of available-for-sale securities	335,355	279,700
Total net cash provided by investing activities	496,928	572,330
Financing activities
Net (decrease) increase in certificates of deposit	(889,195)	31,555
Net decrease in other deposits	(109,679)	(787,295)
Borrowings collateralized by loans in securitization trusts - repaid	(288,840)	(253,176)
Unsecured debt issued	493,885	0
Unsecured debt repaid	(500,000)	0
Common stock dividends paid	(27,466)	(24,278)
Preferred stock dividends paid	(3,956)	(4,653)
Common stock repurchased	(29,696)	(25,457)
Total net cash used in financing activities	(1,356,576)	(1,063,304)
Net decrease in cash, cash equivalents and restricted cash	(1,005,699)	(567,685)
Cash, cash equivalents and restricted cash at beginning of period	4,874,260	4,299,507
Cash, cash equivalents and restricted cash at end of period	3,868,561	3,731,822
Cash disbursements made for:
Interest	300,605	284,041
Income taxes paid	11,366	7,280
Income taxes refunded	(19)	(1,001)
Reconciliation of the Consolidated Statements of Cash Flows to the Consolidated Balance Sheets:
Cash and cash equivalents	3,695,076	3,584,013
Restricted cash	173,485	147,809
Total cash, cash equivalents and restricted cash	3,868,561	3,731,822
Supplemental non-cash investment activities:
Accrued interest capitalized during the period	116,022	118,602
Trading investments received in consideration for loans sold	0	3,072
Available-for-sale investments received in consideration for loans sold	0	111,002
Collateralized Securities
Financing activities
Issuance costs	(20)	0
Unsecured borrowings
Financing activities
Issuance costs	$ (1,609)	$ 0