CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY (USD $) In Thousands, except Share data, unless otherwise specified		Total		Additional Paid-In Capital	Accumulated Other Comprehensive Income (Loss)	Total SLM Corporation Equity	Non-controlling interest	Preferred Stock	Common Stock	Treasury Stock	Retained Earnings	Series A Preferred Stock	Series A Preferred Stock Total SLM Corporation Equity	Series A Preferred Stock Retained Earnings	Series B Preferred Stock	Series B Preferred Stock Total SLM Corporation Equity	Series B Preferred Stock Retained Earnings	Navient's subsidiary investment Additional Paid-In Capital
Beginning Balance, value at Dec. 31, 2012		$ 1,089,300		$ 1,068,928	$ 14,348	$ 1,083,276	$ 6,024
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)		148,667		149,353		149,353	(686)
Other comprehensive income (loss), net of tax		23,442			23,442	23,442
Comprehensive income		172,109				172,795	(686)
Net transfers from affiliate		(55,459)		(55,459)		(55,459)
Cash dividends:
Issuance of common shares, shares	[1]	8,273,219
Ending Balance, value at Jun. 30, 2013		1,205,950		1,162,822	37,790	1,200,612	5,338
Beginning Balance, value at Mar. 31, 2013		1,109,928		1,056,783	47,460	1,104,243	5,685
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)		76,122		76,469		76,469	(347)
Other comprehensive income (loss), net of tax		(9,670)			(9,670)	(9,670)
Comprehensive income		66,452				66,799	(347)
Net transfers from affiliate		29,570		29,570		29,570
Cash dividends:
Issuance of common shares, shares	[1]	4,115,424
Ending Balance, value at Jun. 30, 2013		1,205,950		1,162,822	37,790	1,200,612	5,338
Beginning Balance, value at Dec. 31, 2013		1,166,143		0	(3,024)	1,161,471	4,672	0	0	0	0							1,164,495
Beginning Balance, shares at Dec. 31, 2013								0	0	0
Beginning Balances, shares issued at Dec. 31, 2013									0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)		91,142		0		91,576	(434)				23,403							68,173
Other comprehensive income (loss), net of tax		2,659			2,659	2,659
Comprehensive income		93,801				94,235	(434)
Net transfers from affiliate		479,409				479,409												479,409
Separation adjustments related to Spin-Off of Navient Corporation, shares								7,300,000	422,790,320
Separation adjustments related to Spin-Off of Navient Corporation		0		1,062,519				565,000	84,558									(1,712,077)
Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests		(4,238)					(4,238)
Cash dividends:
Cash dividends, preferred stock												(1,917)	(1,917)	(1,917)	(1,311)	(1,311)	(1,311)
Dividend equivalent units related to employee stock-based compensation plans				8							(8)
Issuance of common shares, shares		504,929	[1]						504,929
Issuance of common shares		2,445		2,344		2,445			101
Stock-based compensation expense		7,045		7,045		7,045
Shares repurchased related to employee stock-based compensation plans, shares									(358,771)	(358,771)
Shares repurchased related to employee stock-based compensation plans		(3,113)				(3,113)				(3,113)
Ending Balance, value at Jun. 30, 2014		1,738,264		1,071,916	(365)	1,738,264	0	565,000	84,659	(3,113)	20,167							0
Ending Balance, shares at Jun. 30, 2014								7,300,000	422,936,478	(358,771)
Ending Balance, shares issued at Jun. 30, 2014									423,295,249
Beginning Balance, value at Mar. 31, 2014		1,231,273		0	(2,152)	1,227,035	4,238	0	0	0	0							1,229,187
Beginning Balance, shares at Mar. 31, 2014								0	0	0
Beginning Balances, shares issued at Mar. 31, 2014									0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)		44,128		0		44,128					23,403							20,725
Other comprehensive income (loss), net of tax		1,787			1,787	1,787
Comprehensive income		45,915				45,915
Net transfers from affiliate		462,165				462,165												462,165
Separation adjustments related to Spin-Off of Navient Corporation, shares								7,300,000	422,790,320
Separation adjustments related to Spin-Off of Navient Corporation				1,062,519				565,000	84,558									(1,712,077)
Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests		(4,238)					(4,238)
Cash dividends:
Cash dividends, preferred stock												(1,917)	(1,917)	(1,917)	(1,311)	(1,311)	(1,311)
Dividend equivalent units related to employee stock-based compensation plans				8							(8)
Issuance of common shares, shares		504,929	[1]						504,929
Issuance of common shares		2,445		2,344		2,445			101
Stock-based compensation expense		7,045		7,045		7,045
Shares repurchased related to employee stock-based compensation plans, shares									(358,771)	(358,771)
Shares repurchased related to employee stock-based compensation plans		(3,113)				(3,113)				(3,113)
Ending Balance, value at Jun. 30, 2014		$ 1,738,264		$ 1,071,916	$ (365)	$ 1,738,264	$ 0	$ 565,000	$ 84,659	$ (3,113)	$ 20,167							$ 0
Ending Balance, shares at Jun. 30, 2014								7,300,000	422,936,478	(358,771)
Ending Balance, shares issued at Jun. 30, 2014									423,295,249

[1] Common shares issued under our various compensation and benefit plans.