CONSOLIDATED STATEMENTS OF INCOME - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Interest income:
Loans	$ 485,997	$ 359,610	$ 1,370,090	$ 1,021,106
Investments	1,340	1,928	4,981	6,272
Cash and cash equivalents	10,260	4,686	22,068	10,429
Total interest income	497,597	366,224	1,397,139	1,037,807
Interest expense:
Deposits	105,093	61,890	273,154	157,473
Interest expense on short-term borrowings	1,156	1,804	4,677	4,234
Interest expense on long-term borrowings	34,715	20,469	89,111	56,070
Total interest expense	140,964	84,163	366,942	217,777
Net interest income	356,633	282,061	1,030,197	820,030
Less: provisions for credit losses	70,047	54,930	187,245	130,441
Net interest income after provisions for credit losses	286,586	227,131	842,952	689,589
Non-interest (loss) income:
Gains on sales of loans, net	0	0	2,060	0
Losses on sales of securities, net	0	0	(1,549)	0
(Losses) gains on derivatives and hedging activities, net	(4,949)	1,661	(6,325)	(7,326)
Other (loss) income	(80,702)	4,455	(58,765)	26,430
Total non-interest (loss) income	(85,651)	6,116	(64,579)	19,104
Non-interest expenses:
Compensation and benefits	62,260	51,052	190,822	157,523
FDIC assessment fees	9,136	7,626	25,933	21,477
Other operating expenses	79,236	57,464	193,974	151,070
Total operating expenses	150,632	116,142	410,729	330,070
Acquired intangible asset amortization expense	92	117	276	351
Total non-interest expenses	150,724	116,259	411,005	330,421
Income before income tax (benefit) expense	50,211	116,988	367,368	378,272
Income tax (benefit) expense	(53,667)	40,617	27,404	136,341
Net income	103,878	76,371	339,964	241,931
Preferred stock dividends	4,124	3,028	11,441	12,577
Net income attributable to SLM Corporation common stock	$ 99,754	$ 73,343	$ 328,523	$ 229,354
Basic earnings per common share attributable to SLM Corporation (in dollars per share)	$ 0.23	$ 0.17	$ 0.76	$ 0.53
Average common shares outstanding (in shares)	435,468	431,718	434,875	430,958
Diluted earnings per common share attributable to SLM Corporation (in dollars per share)	$ 0.23	$ 0.17	$ 0.75	$ 0.52
Average common and common equivalent shares outstanding (in shares)	440,019	438,419	439,484	438,422