Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023
Cash flows from operating activities
Net income	$ 109	$ 177
Adjustments to reconcile net income to net cash provided by operating activities:
Goodwill and acquired intangible asset impairment and amortization expense	5	5
Stock-based compensation expense	12	17
Mark-to-market (gains) losses on derivative and hedging activities, net	(30)	41
Provisions for loan losses	26	(3)
Decrease (increase) in accrued interest receivable	276	(69)
Increase (decrease) in accrued interest payable	12	(7)
Decrease in other assets	79	81
(Decrease) increase in other liabilities	(28)	2
Total adjustments	352	67
Net cash provided by operating activities	461	244
Cash flows from investing activities
Education loans originated and acquired	(610)	(438)
Proceeds from payments on education loans	6,200	4,111
Other investing activities, net	8	1
Net cash provided by investing activities	5,598	3,674
Cash flows from financing activities
Borrowings collateralized by loans in trust - issued	1,106	844
Borrowings collateralized by loans in trust - repaid	(5,154)	(5,837)
Long-term unsecured notes issued	0	495
Long-term unsecured notes repaid	(7)	(1,002)
Other financing activities, net	(53)	(29)
Common stock repurchased	(81)	(165)
Common dividends paid	(35)	(40)
Net cash used in financing activities	(4,846)	(5,457)
Net increase (decrease) in cash, cash equivalents, restricted cash and restricted cash equivalents	1,213	(1,539)
Cash, cash equivalents, restricted cash and restricted cash equivalents at beginning of period	2,793	4,807
Cash, cash equivalents, restricted cash and restricted cash equivalents at end of period	4,006	3,268
Supplemental disclosure of cash flow information:
Interest paid	1,680	1,688
Income taxes paid	30	9
Income taxes refunds received	(1)	(2)
Reconciliation of the Consolidated Statements of Cash Flows to the Consolidated Balance Sheets:
Cash and cash equivalents	1,088	1,317
Restricted cash and cash equivalents	2,918	1,951
Total cash, cash equivalents, restricted cash and restricted cash equivalents at end of period	4,006	3,268
Asset-backed Securities, Securitized Loans and Receivables [Member]
Cash flows from financing activities
Asset-backed commercial paper conduits, net	$ (622)	$ 277