CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023
Operating activities
Net income (loss)	$ 496,772	$ 412,948
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Provisions for credit losses	300,336	329,864
Income tax expense	169,698	140,062
Amortization of brokered deposit placement fee	8,101	8,818
Amortization of Secured Borrowing Facility upfront fee	1,762	2,149
Amortization of deferred loan origination costs and loan premium/(discounts), net	9,203	9,831
Net amortization of discount on investments	(1,480)	(2,012)
Increase in tax indemnification receivable	0	(129)
Depreciation of premises and equipment	13,489	13,404
Acquired intangible assets amortization expense	3,834	7,351
Stock-based compensation expense	31,741	28,300
Unrealized (gains) losses on derivatives and hedging activities, net	62	(280)
Gains on sales of loans, net	(254,937)	(124,740)
Gains on securities, net	(385)	(1,988)
Acquisition transaction costs, net	0	997
Other adjustments to net income, net	8,856	12,279
Changes in operating assets and liabilities:
Increase in accrued interest receivable	(829,087)	(777,125)
Increase in non-marketable securities	(10,553)	(853)
Decrease in other interest-earning assets	3,409	75
Increase in other assets	(41,899)	(31,211)
Decrease in income taxes payable, net	(234,743)	(163,077)
(Decrease) increase in accrued interest payable	(6,121)	27,829
Decrease in other liabilities	(1,992)	(9,988)
Total adjustments	(830,706)	(530,444)
Total net cash used in operating activities	(333,934)	(117,496)
Investing activities
Loans acquired and originated	(6,071,409)	(5,600,123)
Net proceeds from sales of loans held for investment and loans held for sale	3,761,691	2,157,024
Proceeds from FFELP Loan claim payments	27,579	39,836
Net decrease in loans held for investment and loans held for sale (other than loans acquired and originated, and loan sales)	2,021,627	2,338,426
Purchases of available-for-sale securities	(76,963)	(70,790)
Proceeds from sales and maturities of available-for-sale securities	744,798	215,042
Purchase of subsidiary, net of cash acquired	0	(14,654)
Total net cash provided by (used in) investing activities	407,323	(935,239)
Financing activities
Brokered deposit placement fee	(5,906)	(6,904)
Net increase in certificates of deposit	508,686	886,475
Net decrease in other deposits	(727,932)	(796,218)
Issuance costs for collateralized borrowings	0	(15)
Borrowings collateralized by loans in securitization trusts - issued	1,529,461	1,135,054
Borrowings collateralized by loans in securitization trusts - repaid	(727,688)	(863,230)
Fees paid on Secured Borrowing Facility	(2,333)	(2,850)
Common stock dividends paid	(71,834)	(76,817)
Preferred stock dividends paid	(13,929)	(12,979)
Common stock repurchased	(200,898)	(259,331)
Total net cash provided by financing activities	287,627	3,185
Net increase (decrease) in cash, cash equivalents and restricted cash	361,016	(1,049,550)
Cash, cash equivalents and restricted cash at beginning of period	4,299,507	4,772,836
Cash, cash equivalents and restricted cash at end of period	4,660,523	3,723,286
Cash disbursements made for:
Interest	824,375	691,632
Income taxes paid	235,675	171,022
Income taxes refunded	(1,251)	(8,157)
Reconciliation of the Consolidated Statements of Cash Flows to the Consolidated Balance Sheets:
Cash and cash equivalents	4,489,539	3,548,225
Restricted cash	170,984	175,061
Total cash, cash equivalents and restricted cash	$ 4,660,523	$ 3,723,286