CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Operating activities
Net income	$ 289,931	$ 118,518
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Provisions for credit losses	12,041	114,112
Income tax expense	97,554	37,338
Amortization of brokered deposit placement fee	2,803	3,121
Amortization of Secured Borrowing Facility upfront fee	713	723
Amortization of deferred loan origination costs and loan premium/(discounts), net	3,229	3,421
Net amortization of discount on investments	(601)	(622)
Increase in tax indemnification receivable	0	(42)
Depreciation of premises and equipment	4,705	4,524
Acquired intangible assets amortization expense	1,215	2,272
Stock-based compensation expense	13,790	11,536
Unrealized (gains) losses on derivatives and hedging activities, net	20	(56)
(Gains) losses on sales of loans, net	(143,039)	9
Gains on securities, net	(2,118)	(1,711)
Other adjustments to net income, net	2,939	3,063
Changes in operating assets and liabilities:
Increase in accrued interest receivable	(287,000)	(257,888)
Increase in non-marketable securities	(283)	0
Decrease (increase) in other interest-earning assets	1,657	(1,869)
Increase in other assets	(23,046)	(26,632)
(Decrease) increase in income taxes payable, net	(6,463)	2,483
(Decrease) increase in accrued interest payable	(15,738)	20,358
Decrease in other liabilities	(29,020)	(23,770)
Total adjustments	(366,642)	(109,630)
Total net cash (used in) provided by operating activities	(76,711)	8,888
Investing activities
Loans acquired and originated	(2,593,293)	(2,463,358)
Net proceeds from sales of loans held for investment and loans held for sale	2,149,774	(9)
Proceeds from FFELP Loan claim payments	10,819	11,274
Net decrease in loans held for investment and loans held for sale (other than loans acquired and originated, and loan sales)	751,120	912,681
Purchases of available-for-sale securities	(25,790)	(4,992)
Proceeds from sales and maturities of available-for-sale securities	279,700	73,352
Total net cash provided by (used in) investing activities	572,330	(1,471,052)
Financing activities
Brokered deposit placement fee	0	(2,634)
Net increase in certificates of deposit	31,555	515,909
Net decrease in other deposits	(787,295)	(167,836)
Borrowings collateralized by loans in securitization trusts - issued	0	569,871
Borrowings collateralized by loans in securitization trusts - repaid	(253,176)	(293,120)
Fees paid on Secured Borrowing Facility	0	(16)
Common stock dividends paid	(24,278)	(26,635)
Preferred stock dividends paid	(4,653)	(4,063)
Common stock repurchased	(25,457)	(4,005)
Total net cash (used in) provided by financing activities	(1,063,304)	587,471
Net decrease in cash, cash equivalents and restricted cash	(567,685)	(874,693)
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	3,731,822	3,898,143
Cash disbursements made for:
Interest	284,041	198,874
Income taxes paid	7,280	4,700
Income taxes refunded	(1,001)	(7,273)
Reconciliation of the Consolidated Statements of Cash Flows to the Consolidated Balance Sheets:
Cash and cash equivalents	3,584,013	3,716,379
Restricted cash	147,809	181,764
Total cash, cash equivalents and restricted cash	$ 3,731,822	$ 3,898,143