Maximum contribution amount per employee to ESPP.

No definition available.

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- Definition

Maximum term for stock options, in years.

+ References

No definition available.

+ Details

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- Definition

Offering period of employee stock purchase plan.

+ References

No definition available.

+ Details

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- Definition

Share Based Compensation arrangement by share based payment award approval date.

+ References

No definition available.

+ Details

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award Award Vesting Periods

+ References

No definition available.

+ Details

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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (i)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

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- Definition

Discount rate from fair value on offering date that participants pay for shares.

+ References

+ Details

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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)(3)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

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- Definition

The number of shares purchased on the open market during the period for issuance to employees under the plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901

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Stock-Based Compensation Plans and Arrangements - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation cost	$ 15,681,000	$ 19,102,000	$ 22,362,000
Weighted average period for total unrecognized compensation cost	1 year 9 months 18 days
Offering period of employee stock purchase plan	12 months
Maximum contribution amount per employee to ESPP	7,500
SLM Corporation 2012 Omnibus Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Approval date	May 24, 2012
Shares authorized to be issued under plan	20,000,000
Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Approval date	May 24, 2012
Shares authorized to be issued under plan	6,000,000
Unrecognized compensation cost	18,750,000
Percentage of discount available to employees under ESPP	15.00%
Grants made prior to 2012 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum term for stock options (in years)	10 years
Grants made in 2012 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum term for stock options (in years)	5 years
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average period for total unrecognized compensation cost	1 month 6 days
Unrecognized compensation cost	$ 7,000
Restricted Stock Units, RSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting Period	RSUs may be time-vested over three years or vested at grant but subject to transfer restrictions
Performance Stock Units, PSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting Period	PSUs vest based on corporate earnings-related performance targets over a three-year period
Employee Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of the Company's common stock purchased by ESPP participants	47,176	34,279	41,330