CONSOLIDATED STATEMENTS OF INCOME - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Interest income:
Loans	$ 442,576	$ 477,833	$ 1,304,479	$ 1,513,279
Investments	3,366	3,327	9,262	9,086
Cash and cash equivalents	1,613	1,218	4,662	19,740
Total interest income	447,555	482,378	1,318,403	1,542,105
Interest expense:
Deposits	51,629	83,500	175,483	318,858
Interest expense on short-term borrowings	5,458	3,424	14,360	11,041
Interest expense on long-term borrowings	32,950	30,887	101,144	98,750
Total interest expense	90,037	117,811	290,987	428,649
Net interest income	357,518	364,567	1,027,416	1,113,456
Less: provisions for credit losses	138,442	(3,640)	(17,648)	409,505
Net interest income after provisions for credit losses	219,076	368,207	1,045,064	703,951
Non-interest income:
Gains (losses) on sales of loans, net	(10)	(4)	402,780	238,562
Gains (losses) on derivatives and hedging activities, net	44	(15)	161	49,408
Other income	13,879	9,646	76,747	42,547
Total non-interest income	13,913	9,627	479,688	330,517
Operating expenses
Compensation and benefits	66,229	62,743	200,426	219,413
FDIC assessment fees	6,521	1,455	17,634	17,508
Other operating expenses	67,899	63,292	175,098	179,424
Total operating expenses	140,649	127,490	393,158	416,345
Restructuring expenses	108	24,127	1,255	24,127
Total non-interest expenses	140,757	151,617	394,413	440,472
Income before income tax expense	92,232	226,217	1,130,339	593,996
Income tax expense	19,392	55,189	276,091	146,006
Net income	72,840	171,028	854,248	447,990
Preferred stock dividends	1,166	2,058	3,559	8,000
Net income attributable to SLM Corporation common stock	71,674	168,970	850,689	439,990
Net income attributable to SLM Corporation common stock	$ 71,674	$ 168,970	$ 850,689	$ 439,990
Basic earnings per common share attributable to SLM Corporation (in dollars per share)	$ 0.24	$ 0.45	$ 2.62	$ 1.14
Average common shares outstanding (in shares)	299,890,000	375,094,000	324,148,000	386,587,000
Diluted earnings per common share attributable to SLM Corporation (in dollars per share)	$ 0.24	$ 0.45	$ 2.59	$ 1.13
Average common and common equivalent shares outstanding (in shares)	304,511,000	377,918,000	329,064,000	389,391,000
Declared dividends per common share attributable to SLM Corporation (in dollars per share)	$ 0.03	$ 0	$ 0.09	$ 0.09