CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Statement of Comprehensive Income [Abstract]
Net income	$ 47,699us-gaap_ProfitLoss	$ 47,014us-gaap_ProfitLoss
Other comprehensive income (loss):
Unrealized gains on investments	673	1,406
Unrealized losses on cash flow hedges	(15,689)	0
Total unrealized gains (losses)	(15,016)	1,406
Income tax (expense) benefit	5,825us-gaap_OtherComprehensiveIncomeLossTax	(534)us-gaap_OtherComprehensiveIncomeLossTax
Other comprehensive income (loss), net of tax benefit (expense)	(9,191)	872
Comprehensive income	38,508	47,886
Less: comprehensive loss attributable to noncontrolling interest	0	(434)
Total comprehensive income attributable to SLM Corporation	$ 38,508	$ 48,320

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income (loss) and other comprehensive income (loss), attributable to noncontrolling interests. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount before tax, after reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities. Excludes amounts related to other than temporary impairment (OTTI) loss.

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Amount of tax expense (benefit) allocated to other comprehensive income (loss).

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