CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Statement of Comprehensive Income [Abstract]
Net income	$ 44,128	$ 76,122	$ 91,142	$ 148,667
Other comprehensive income (loss):
Unrealized gain (loss) on investments	2,749	(15,625)	4,155	37,769
Total unrealized gains (losses) on investments	2,749	(15,625)	4,155	37,769
Income tax (expense) benefit	(962)	5,955	(1,496)	(14,327)
Other comprehensive income (loss), net of tax benefit (expense)	1,787	(9,670)	2,659	23,442
Comprehensive income	45,915	66,452	93,801	172,109
Less: comprehensive loss attributable to noncontrolling interest	0	(347)	(434)	(686)
Total comprehensive income attributable to SLM Corporation	$ 45,915	$ 66,799	$ 94,235	$ 172,795