CONSOLIDATED STATEMENTS OF INCOME - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Interest income:
Loans	$ 553,905	$ 454,045	$ 1,107,384	$ 884,093
Investments	1,706	1,694	3,127	3,641
Cash and cash equivalents	18,111	6,572	29,664	11,808
Total interest income	573,722	462,311	1,140,175	899,542
Interest expense:
Deposits	136,597	90,605	262,584	168,061
Interest expense on short-term borrowings	1,135	1,128	2,300	3,521
Interest expense on long-term borrowings	39,122	29,628	76,142	54,396
Total interest expense	176,854	121,361	341,026	225,978
Net interest income	396,868	340,950	799,149	673,564
Less: provisions for credit losses	93,375	63,267	157,165	117,198
Net interest income after provisions for credit losses	303,493	277,683	641,984	556,366
Non-interest income:
Gains on sales of loans, net	0	2,060	0	2,060
Losses on sales of securities, net	0	(1,549)	0	(1,549)
Gains (losses) on derivatives and hedging activities, net	16,736	(5,268)	19,499	(1,376)
Other income	2,655	12,295	16,033	21,937
Total non-interest income	19,391	7,538	35,532	21,072
Non-interest expenses:
Compensation and benefits	66,495	60,245	145,233	128,562
FDIC assessment fees	7,356	8,001	14,974	16,797
Other operating expenses	64,955	67,069	118,746	114,922
Total non-interest expenses	138,806	135,315	278,953	260,281
Income before income tax expense	184,078	149,906	398,563	317,157
Income tax expense	33,801	40,074	90,097	81,071
Net income	150,277	109,832	308,466	236,086
Preferred stock dividends	4,331	3,920	8,799	7,317
Net income attributable to SLM Corporation common stock	$ 145,946	$ 105,912	$ 299,667	$ 228,769
Basic earnings per common share attributable to SLM Corporation (in dollars per share)	$ 0.34	$ 0.24	$ 0.69	$ 0.53
Average common shares outstanding (in shares)	429,278,000	435,187,000	431,911,000	434,573,000
Diluted earnings per common share attributable to SLM Corporation (in dollars per share)	$ 0.34	$ 0.24	$ 0.69	$ 0.52
Average common and common equivalent shares outstanding (in shares)	432,253,000	439,445,000	435,233,000	439,212,000
Dividends per common share attributable to SLM Corporation (in dollars per share)	$ 0.06	$ 0	$ 0.09	$ 0