SLM (SLM) 10-Q 19 Oct 16 2016 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information	9 Months Ended
	Sep. 30, 2016shares
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2016
Document Fiscal Year Focus	2,016
Document Fiscal Period Focus	Q3
Trading Symbol	SLM
Entity Registrant Name	SLM CORPORATION
Entity Central Index Key	1,032,033
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding (in shares)	428,267,726

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Assets
Cash and cash equivalents	$ 1,454,938	$ 2,416,219
Available-for-sale investments at fair value (cost of $209,464 and $196,402, respectively)	213,176	195,391
Loans held for investment (net of allowance for losses of $164,839 and $112,507, respectively)	14,760,504	11,630,591
Restricted cash and investments	38,256	27,980
Other interest-earning assets	47,283	54,845
Accrued interest receivable	805,647	564,496
Premises and equipment, net	86,721	81,273
Tax indemnification receivable	276,543	186,076
Other assets	62,545	57,227
Total assets	17,745,613	15,214,098
Liabilities
Deposits	12,941,345	11,487,707
Short-term borrowings	350,000	500,175
Long-term borrowings	1,577,689	579,101
Income taxes payable, net	199,813	166,662
Upromise related liabilities	259,290	275,384
Other liabilities	157,980	108,746
Total liabilities	15,486,117	13,117,775
Commitments and contingencies
Equity
Common stock, par value $0.20 per share, 1.125 billion shares authorized: 434.4 million and 430.7 million shares issued, respectively	86,881	86,136
Additional paid-in capital	1,157,248	1,135,860
Accumulated other comprehensive loss (net of tax benefit of $17,253 and $9,949, respectively)	(27,813)	(16,059)
Retained earnings	530,594	366,609
Total SLM Corporation stockholders’ equity before treasury stock	2,311,910	2,137,546
Less: Common stock held in treasury at cost: 6.1 million and 4.4 million shares, respectively	(52,414)	(41,223)
Total equity	2,259,496	2,096,323
Total liabilities and equity	17,745,613	15,214,098
Series A Preferred Stock
Equity
Preferred stock value outstanding	165,000	165,000
Series B Preferred Stock
Equity
Preferred stock value outstanding	$ 400,000	$ 400,000

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Amortized cost	$ 209,464	$ 196,402
Allowance for loan losses	164,839	112,507
Tax benefit for accumulated other comprehensive (loss) income	$ (17,253)	$ (9,949)
Preferred stock, stated value (in dollars per share)	$ 0.20	$ 0.20
Preferred stock shares authorized (in shares)	20,000,000	20,000,000
Common stock par value (in dollars per share)	$ 0.20	$ 0.20
Common stock, shares authorized (in shares)	1,125,000,000	1,125,000,000
Common stock shares issued (in shares)	434,400,000	430,700,000
Common stock held in treasury (in shares)	6,100,000	4,400,000
Series A Preferred Stock
Preferred stock, stated value (in dollars per share)	$ 50	$ 50
Preferred stock shares outstanding (in shares)	3,300,000	3,300,000
Series B Preferred Stock
Preferred stock, stated value (in dollars per share)	$ 100	$ 100
Preferred stock shares outstanding (in shares)	4,000,000	4,000,000

CONSOLIDATED STATEMENTS OF INCO

CONSOLIDATED STATEMENTS OF INCOME - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Interest income:
Loans	$ 268,341	$ 205,274	$ 765,246	$ 598,417
Investments	2,193	2,640	7,155	7,746
Cash and cash equivalents	2,003	987	4,832	2,568
Total interest income	272,537	208,901	777,233	608,731
Interest expense:
Deposits	38,210	29,110	107,633	86,961
Interest expense on short-term borrowings	1,604	1,951	5,827	4,719
Interest expense on long-term borrowings	9,448	2,398	17,869	2,398
Total interest expense	49,262	33,459	131,329	94,078
Net interest income	223,275	175,442	645,904	514,653
Less: provisions for credit losses	41,784	27,497	116,179	59,673
Net interest income after provisions for credit losses	181,491	147,945	529,725	454,980
Non-interest income:
Gains on sales of loans, net	0	0	0	76,874
Gains (losses) on derivatives and hedging activities, net	1,368	(547)	3,156	4,347
Other income	21,598	10,455	56,309	29,374
Total non-interest income	22,966	9,908	59,465	110,595
Non-interest expenses:
Compensation and benefits	43,380	39,304	138,659	119,079
FDIC assessment fees	5,095	3,801	13,548	10,230
Other operating expenses	51,234	49,759	135,164	134,541
Total operating expenses	99,709	92,864	287,371	263,850
Acquired intangible asset amortization expense	226	370	747	1,110
Restructuring and other reorganization expenses	0	910	0	6,311
Total non-interest expenses	99,935	94,144	288,118	271,271
Income before income tax expense	104,522	63,709	301,072	294,304
Income tax expense	47,557	17,985	120,987	109,865
Net income	56,965	45,724	180,085	184,439
Preferred stock dividends	5,316	4,913	15,698	14,606
Net income attributable to SLM Corporation common stock	$ 51,649	$ 40,811	$ 164,387	$ 169,833
Basic earnings per common share attributable to SLM Corporation (in dollars per share)	$ 0.12	$ 0.10	$ 0.38	$ 0.40
Average common shares outstanding (in shares)	428,077	426,019	427,711	425,384
Diluted earnings per common share attributable to SLM Corporation (in dollars per share)	$ 0.12	$ 0.09	$ 0.38	$ 0.39
Average common and common equivalent shares outstanding (in shares)	433,523	432,547	432,079	432,531

CONSOLIDATED STATEMENTS OF COMP

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Statement of Comprehensive Income [Abstract]
Net income	$ 56,965	$ 45,724	$ 180,085	$ 184,439
Other comprehensive income (loss):
Unrealized gains (losses) on investments	406	2,008	4,723	(499)
Unrealized gains (losses) on cash flow hedges	9,324	(21,751)	(23,782)	(19,284)
Total unrealized gains (losses)	9,730	(19,743)	(19,059)	(19,783)
Income tax (expense) benefit	(3,690)	7,676	7,305	7,661
Other comprehensive income (loss), net of tax (expense) benefit	6,040	(12,067)	(11,754)	(12,122)
Total comprehensive income	$ 63,005	$ 33,657	$ 168,331	$ 172,317

CONSOLIDATED STATEMENTS OF CHAN

CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY - USD ($) $ in Thousands	Total	Series A Preferred Stock	Series B Preferred Stock	Preferred Stock	Common Stock	Treasury Stock	Additional Paid-In Capital	Accumulated Other Comprehensive Income (Loss)	Retained Earnings	Retained EarningsSeries A Preferred Stock	Retained EarningsSeries B Preferred Stock
Beginning Balance (in shares) at Dec. 31, 2014				7,300,000	423,438,848	(1,365,277)
Beginning Balance, shares issued (in shares) at Dec. 31, 2014					424,804,125
Beginning Balance at Dec. 31, 2014	$ 1,829,958			$ 565,000	$ 84,961	$ (12,187)	$ 1,090,511	$ (11,393)	$ 113,066
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	184,439								184,439
Other comprehensive loss, net of tax	(12,122)							(12,122)
Total comprehensive income	172,317
Cash dividends:
Cash dividends, preferred stock		$ (8,625)	$ (5,981)							$ (8,625)	$ (5,981)
Dividend equivalent units related to employee stock-based compensation plans	$ 0						1,138		(1,138)
Issuance of common shares (in shares)	5,569,853				5,569,853
Issuance of common shares	$ 15,443				$ 1,114		14,329
Tax benefit related to employee stock-based compensation	6,093						6,093
Stock-based compensation expense	16,423						16,423
Shares repurchased related to employee stock-based compensation plans (in shares)					(2,900,266)	(2,900,266)
Shares repurchased related to employee stock-based compensation plans	(28,294)					$ (28,294)
Ending Balance (in shares) at Sep. 30, 2015				7,300,000	426,108,435	(4,265,543)
Ending Balance, shares issued (in shares) at Sep. 30, 2015					430,373,978
Ending Balance at Sep. 30, 2015	1,997,334			$ 565,000	$ 86,075	$ (40,481)	1,128,494	(23,515)	281,761
Beginning Balance (in shares) at Dec. 31, 2015				7,300,000	426,303,244	(4,374,190)
Beginning Balance, shares issued (in shares) at Dec. 31, 2015					430,677,434
Beginning Balance at Dec. 31, 2015	2,096,323			$ 565,000	$ 86,136	$ (41,223)	1,135,860	(16,059)	366,609
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	180,085								180,085
Other comprehensive loss, net of tax	(11,754)							(11,754)
Total comprehensive income	168,331
Cash dividends:
Cash dividends, preferred stock		$ (8,625)	$ (7,073)							$ (8,625)	$ (7,073)
Dividend equivalent units related to employee stock-based compensation plans	$ 0						402		(402)
Issuance of common shares (in shares)	3,727,574				3,727,574
Issuance of common shares	$ 6,238				$ 745		5,493
Tax deficiency related to employee stock-based compensation	(2,457)						(2,457)
Stock-based compensation expense	17,950						17,950
Shares repurchased related to employee stock-based compensation plans (in shares)					(1,763,092)	(1,763,092)
Shares repurchased related to employee stock-based compensation plans	(11,191)					$ (11,191)
Ending Balance (in shares) at Sep. 30, 2016				7,300,000	428,267,726	(6,137,282)
Ending Balance, shares issued (in shares) at Sep. 30, 2016					434,405,008
Ending Balance at Sep. 30, 2016	$ 2,259,496			$ 565,000	$ 86,881	$ (52,414)	$ 1,157,248	$ (27,813)	$ 530,594

CONSOLIDATED STATEMENTS OF CHA7

CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY (Parenthetical) - $ / shares	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Series A Preferred Stock
Preferred stock dividend rate (in dollars per share)	$ 0.87	$ 0.87
Series B Preferred Stock
Preferred stock dividend rate (in dollars per share)	$ 0.65	$ 0.51

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Operating activities
Net income	$ 180,085	$ 184,439
Adjustments to reconcile net income to net cash used in operating activities:
Provisions for credit losses	116,179	59,673
Income tax expense	120,987	109,865
Amortization of brokered deposit placement fee	7,766	8,006
Amortization of ABCP Facility upfront fee	866	1,790
Amortization of deferred loan origination costs and fees, net	4,304	2,563
Net amortization of discount on investments	1,387	1,332
Interest income on tax indemnification receivable	(14,386)	(5,118)
Depreciation of premises and equipment	6,896	5,427
Amortization of acquired intangibles	747	1,110
Stock-based compensation expense	17,950	16,423
Unrealized gains on derivative and hedging activities, net	(1,881)	(1,985)
Gains on sale of loans, net	0	(76,874)
Other adjustments to net income, net	2,540	216
Changes in operating assets and liabilities:
Net decrease in loans held for sale	0	55
Origination of loans held for sale	0	(55)
Increase in accrued interest receivable	(430,441)	(316,263)
Decrease (increase) in restricted cash and investments - other	1,564	(2,596)
Decrease in other interest-earning assets	7,562	24,875
Decrease in tax indemnification receivable	44,725	44,725
Increase in other assets	(22,879)	(18,022)
Decrease in income taxes payable, net	(201,338)	(176,172)
Increase in accrued interest payable	10,202	7,227
Increase (decrease) in payable due to entity that is a subsidiary of Navient	658	(5,368)
Increase in other liabilities	7,131	5,895
Total adjustments	(319,461)	(313,271)
Total net cash used in operating activities	(139,376)	(128,832)
Investing activities
Loans acquired and originated	(4,072,631)	(3,786,946)
Net proceeds from sales of loans held for investment	7,912	790,094
Proceeds from claim payments	49,742	91,000
Net decrease in loans held for investment	953,715	672,665
Increase in restricted cash and investments - variable interest entities	(11,840)	(18,205)
Purchases of available-for-sale securities	(40,767)	(50,062)
Proceeds from sales and maturities of available-for-sale securities	26,318	26,222
Total net cash used in investing activities	(3,087,551)	(2,275,232)
Financing activities
Brokered deposit placement fee	(3,953)	(477)
Net increase in certificates of deposit	481,623	161,096
Net increase (decrease) in other deposits	961,123	(129,412)
Issuance costs for collateralized borrowings	(1,351)	0
Borrowings collateralized by loans in securitization trusts - issued	1,104,551	620,681
Borrowings collateralized by loans in securitization trusts - repaid	(106,567)	(27,195)
Borrowings under ABCP Facility	376,325	713,746
Repayment of borrowings under ABCP Facility	(526,500)	(3,741)
Fees paid on ABCP Facility	(1,450)	(104)
Excess tax (expense) benefit from the exercise of stock-based awards	(2,457)	6,093
Preferred stock dividends paid	(15,698)	(14,606)
Net cash provided by financing activities	2,265,646	1,326,081
Net decrease in cash and cash equivalents	(961,281)	(1,077,983)
Cash and cash equivalents at beginning of period	2,416,219	2,359,780
Cash and cash equivalents at end of period	1,454,938	1,281,797
Cash disbursements made for:
Interest	119,812	79,917
Income taxes paid	201,218	171,194
Income taxes received	$ (86)	$ (80)

Significant Accounting Policies

Significant Accounting Policies	9 Months Ended
	Sep. 30, 2016
Accounting Policies [Abstract]
Significant Accounting Policies	Significant Accounting Policies Basis of Presentation The accompanying unaudited, consolidated financial statements of SLM Corporation (“Sallie Mae,” “SLM,” the “Company,” “we,” or “us”) have been prepared in accordance with generally accepted accounting principles in the United States of America (“GAAP”) for interim financial information. Accordingly, they do not include all the information and footnotes required by GAAP for complete consolidated financial statements. The consolidated financial statements include the accounts of SLM Corporation and its majority-owned and controlled subsidiaries after eliminating the effects of intercompany accounts and transactions. In the opinion of management, all adjustments considered necessary for a fair statement of the results for the interim periods have been included. The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying notes. Actual results could differ from those estimates. Operating results for the three and nine months ended September 30, 2016 are not necessarily indicative of the results for the year ending December 31, 2016 or for any other period. These unaudited financial statements should be read in conjunction with the audited financial statements and related notes included in our Annual Report on Form 10-K for the year ended December 31, 2015 (the “2015 Form 10-K”). Correction Recorded in the Current Period We recognized in the current period adjustments for tax positions relating to historical transactions among entities that are now subsidiaries of Navient Corporation (“Navient”) that should have been recorded at the time of the separation of Navient from SLM (the “Spin-Off”), which occurred on April 30, 2014. We have evaluated the quantitative and qualitative materiality of these errors to all of the relevant periods and concluded that the out of period correction to recognize the asset, liabilities and income statement impacts in the quarter ended September 30, 2016 is not material to our consolidated financial statements for any of the relevant periods. The adjustments increased our tax indemnification receivable and income taxes payable by $ 120 million and increased our other income and income tax expense by $ 9 million, as we believe we are indemnified by Navient for these additional tax liabilities. Accordingly, there was no effect on equity or net income as a result of these errors in the current or prior periods. Prospectively, these uncertain tax position liabilities and related assets will be accounted for consistent with our existing accounting policies for these kinds of assets and liabilities. Consolidation The consolidated financial statements include the accounts of the Company and its majority-owned and controlled subsidiaries after eliminating the effects of intercompany accounts and transactions. We consolidate any variable interest entity (“VIE”) where we have determined we are the primary beneficiary. The primary beneficiary is the entity which has both: (1) the power to direct the activities of the VIE that most significantly impact the VIE’s economic performance and (2) the obligation to absorb losses or receive benefits of the entity that could potentially be significant to the VIE. Loan Interest Income For loans classified as “held for investment,” we recognize interest income as earned, adjusted for the amortization of deferred direct origination costs. This adjustment is recognized based upon the expected yield of the loan over its life after giving effect to prepayments and extensions. We consider our constant prepayment rate (“CPR”) estimates a significant accounting assumption used to measure the expected prepayment activity in our education loan portfolio. The estimates are based on a number of factors such as historical prepayment rates for loans with similar loan characteristics, assumptions about portfolio composition and loan terms, and the prepayment curve’s tendency to follow a ramp pattern (i.e., the prepayment rate typically increases during the in-school and early repayment periods, then stabilizes). The CPR measures the expected prepayment activity over the life of the loan and is applied as a flat-rate input assumption when used in forecasting. Our CPR estimates include the effect of voluntary prepayments, education loan defaults, and consolidation (if the loans are consolidated to third parties), all of which shorten the lives of loans. CPR estimates also consider the utilization of deferment, forbearance, and extended repayment plans, which lengthen the lives of loans. We regularly evaluate the assumptions used to estimate the CPRs. In instances where there are changes to the assumptions, amortization of deferred direct origination costs is adjusted on a cumulative basis to reflect the change since the origination of the loan. We also pay to the U.S. Department of Education (“ED”) an annual 105 basis point Consolidation Loan Rebate Fee on FFELP consolidation loans, which is netted against loan interest income. Additionally, interest earned on education loans reflects potential non-payment adjustments in accordance with our uncollectible interest recognition policy. We do not amortize any adjustments to the basis of education loans when they are classified as “held-for-sale.” We recognize certain fee income (primarily late fees) on education loans when earned according to the contractual provisions of the promissory notes, as well as our expectation of collectibility. Fee income is recorded when earned in “other non-interest income” in the accompanying consolidated statements of income. Recently Issued but Not Yet Adopted Accounting Pronouncements On February 25, 2016, the Financial Accounting Standards Board (the “FASB”) issued Accounting Standards Update (“ASU”) No. 2016-02, “Leases,” a comprehensive new lease standard which will supersede previous lease guidance. The standard requires a lessee to recognize in its balance sheet assets and liabilities related to long-term leases that were classified as operating leases under previous guidance. An asset will be recognized related to the right to use the underlying asset and a liability will be recognized related to the obligation to make lease payments over the term of the lease. The standard also requires expanded disclosures surrounding leases. The standard is effective for fiscal periods beginning after December 15, 2018, and requires modified retrospective adoption, with early adoption permitted. We are currently evaluating the impact of the adoption of this standard on our consolidated financial statements and related disclosures. On March 30, 2016, the FASB issued ASU No. 2016-09, “Compensation - Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting,” which amends the current stock compensation guidance. The amendments simplify the accounting for the taxes related to stock-based compensation, including adjustments to how excess tax benefits and a company’s payments for tax withholdings should be classified. The standard is effective for fiscal periods beginning after December 15, 2016, with early adoption permitted. We continue to evaluate the impact of the adoption of this standard on our consolidated financial statements, and at this time we expect the standard to result in immaterial volatility in earnings caused by the change in the treatment of the tax benefits or deficiencies related to share-based payments at settlement (or expiration) through “income tax expense” in our consolidated statements of income. On June 16, 2016, the FASB issued ASU No. 2016-13, “Financial Instruments—Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments,” which requires measurement and recognition of expected credit losses for financial assets held. Under this standard, we will be required to hold an allowance equal to the expected life-of-loan losses on our loan portfolio. The standard is effective for fiscal periods beginning after December 15, 2019. While we are currently evaluating the impact of our pending adoption of this standard on our consolidated financial statements, we expect the adoption to have a material impact on our consolidated financial statements and capital ratios.

Loans Held for Investment

Loans Held for Investment	9 Months Ended
	Sep. 30, 2016
Receivables [Abstract]
Loans Held for Investment	Loans Held for Investment Loans held for investment consist of Private Education Loans and FFELP Loans. We use “Private Education Loans” to mean education loans to students or their families that are not made, insured or guaranteed by any state or federal government. Private Education Loans do not include loans insured or guaranteed under the previously existing Federal Family Education Loan Program (“FFELP”). Our Private Education Loans are made largely to bridge the gap between the cost of higher education and the amount funded through financial aid, government loans and customers’ resources. Private Education Loans bear the full credit risk of the customer. We manage this risk through risk-performance underwriting strategies and qualified cosigners. Private Education Loans generally carry a variable rate indexed to LIBOR. As of September 30, 2016 , 81 percent of all of our Private Education Loans were indexed to LIBOR. We provide incentives for customers to include a cosigner on the loan, and the vast majority of loans in our portfolio are cosigned. We also provide total cost incentives for customers to make payments while in school. FFELP Loans are insured as to their principal and accrued interest in the event of default subject to a Risk Sharing level based on the date of loan disbursement. These insurance obligations are supported by contractual rights against the United States. For loans disbursed on or after July 1, 2006, we receive 97 percent reimbursement on all qualifying claims. For loans disbursed after October 1, 1993, and before July 1, 2006, we receive 98 percent reimbursement on all qualifying claims. For loans disbursed prior to October 1, 1993, we receive 100 percent reimbursement on all qualifying claims. Loans held for investment are summarized as follows: September 30, December 31, 2016 2015 Private Education Loans $ 13,848,262 $ 10,596,437 Deferred origination costs 40,327 27,884 Allowance for loan losses (162,630 ) (108,816 ) Total Private Education Loans, net 13,725,959 10,515,505 FFELP Loans 1,033,929 1,115,663 Unamortized acquisition costs, net 2,825 3,114 Allowance for loan losses (2,209 ) (3,691 ) Total FFELP Loans, net 1,034,545 1,115,086 Loans held for investment, net $ 14,760,504 $ 11,630,591 The estimated weighted average life of education loans in our portfolio was approximately 6.0 years and 6.2 years at September 30, 2016 and December 31, 2015 , respectively. The average balance and the respective weighted average interest rates of education loans in our portfolio are summarized as follows: Three Months Ended Nine Months Ended September 30, September 30, 2016 2015 2016 2015 Average Balance Weighted Average Interest Rate Average Balance Weighted Average Interest Rate Average Balance Weighted Average Interest Rate Average Balance Weighted Average Interest Rate Private Education Loans $ 12,881,890 8.00 % $ 9,869,025 7.87 % $ 12,307,932 8.00 % $ 9,563,290 7.96 % FFELP Loans 1,049,803 3.52 1,161,288 3.27 1,076,394 3.48 1,196,491 3.22 Total portfolio $ 13,931,693 $ 11,030,313 $ 13,384,326 $ 10,759,781

Allowance for Loan Losses

Allowance for Loan Losses	9 Months Ended
	Sep. 30, 2016
Receivables [Abstract]
Allowance for Loan Losses	Allowance for Loan Losses Our provision for loan losses represents the periodic expense of maintaining an allowance sufficient to absorb incurred probable losses in the held-for-investment loan portfolios. The evaluation of the allowance for loan losses is inherently subjective, as it requires material estimates that may be susceptible to significant changes. We believe the allowance for loan losses is appropriate to cover probable losses incurred in the loan portfolios. Allowance for Loan Losses Metrics Allowance for Loan Losses Three Months Ended September 30, 2016 FFELP Loans Private Education Loans Total Allowance for Loan Losses Beginning balance $ 2,297 $ 142,628 $ 144,925 Total provision 268 40,502 40,770 Net charge-offs: Charge-offs (356 ) (22,072 ) (22,428 ) Recoveries — 2,973 2,973 Net charge-offs (356 ) (19,099 ) (19,455 ) Loan sales (1) — (1,401 ) (1,401 ) Ending Balance $ 2,209 $ 162,630 $ 164,839 Allowance: Ending balance: individually evaluated for impairment $ — $ 77,521 $ 77,521 Ending balance: collectively evaluated for impairment $ 2,209 $ 85,109 $ 87,318 Loans: Ending balance: individually evaluated for impairment $ — $ 503,632 $ 503,632 Ending balance: collectively evaluated for impairment $ 1,033,929 $ 13,344,630 $ 14,378,559 Net charge-offs as a percentage of average loans in repayment (annualized) (2) 0.18 % 0.91 % Allowance as a percentage of the ending total loan balance 0.21 % 1.17 % Allowance as a percentage of the ending loans in repayment (2) 0.28 % 1.83 % Allowance coverage of net charge-offs (annualized) 1.55 2.13 Ending total loans, gross $ 1,033,929 $ 13,848,262 Average loans in repayment (2) $ 791,296 $ 8,420,625 Ending loans in repayment (2) $ 795,665 $ 8,905,812 ____________ (1) Represents fair value adjustments on loans sold. (2) Loans in repayment include loans on which borrowers are making interest only or fixed payments, as well as loans that have entered full principal and interest repayment status after any applicable grace period. Allowance for Loan Losses Three Months Ended September 30, 2015 FFELP Loans Private Education Loans Total Allowance for Loan Losses Beginning balance $ 4,556 $ 87,310 $ 91,866 Total provision 143 27,354 27,497 Net charge-offs: Charge-offs (529 ) (14,121 ) (14,650 ) Recoveries — 1,361 1,361 Net charge-offs (529 ) (12,760 ) (13,289 ) Loan sales (1) — (1,871 ) (1,871 ) Ending Balance $ 4,170 $ 100,033 $ 104,203 Allowance: Ending balance: individually evaluated for impairment $ — $ 43,001 $ 43,001 Ending balance: collectively evaluated for impairment $ 4,170 $ 57,032 $ 61,202 Loans: Ending balance: individually evaluated for impairment $ — $ 231,286 $ 231,286 Ending balance: collectively evaluated for impairment $ 1,143,595 $ 10,608,975 $ 11,752,570 Net charge-offs as a percentage of average loans in repayment (annualized) (2) 0.25 % 0.83 % Allowance as a percentage of the ending total loan balance 0.36 % 0.92 % Allowance as a percentage of the ending loans in repayment (2) 0.50 % 1.50 % Allowance coverage of net charge-offs (annualized) 1.97 1.96 Ending total loans, gross $ 1,143,595 $ 10,840,261 Average loans in repayment (2) $ 839,090 $ 6,118,678 Ending loans in repayment (2) $ 836,585 $ 6,657,228 ____________ (1) Represents fair value adjustments on loans sold. (2) Loans in repayment include loans on which borrowers are making interest only or fixed payments, as well as loans that have entered full principal and interest repayment status after any applicable grace period. Allowance for Loan Losses Nine Months Ended September 30, 2016 FFELP Loans Private Education Loans Total Allowance for Loan Losses Beginning balance $ 3,691 $ 108,816 $ 112,507 Total provision (396 ) 116,703 116,307 Net charge-offs: Charge-offs (1,086 ) (64,979 ) (66,065 ) Recoveries — 7,098 7,098 Net charge-offs (1,086 ) (57,881 ) (58,967 ) Loan sales (1) — (5,008 ) (5,008 ) Ending Balance $ 2,209 $ 162,630 $ 164,839 Allowance: Ending balance: individually evaluated for impairment $ — $ 77,521 $ 77,521 Ending balance: collectively evaluated for impairment $ 2,209 $ 85,109 $ 87,318 Loans: Ending balance: individually evaluated for impairment $ — $ 503,632 $ 503,632 Ending balance: collectively evaluated for impairment $ 1,033,929 $ 13,344,630 $ 14,378,559 Net charge-offs as a percentage of average loans in repayment (annualized) (2) 0.18 % 0.97 % Allowance as a percentage of the ending total loan balance 0.21 % 1.17 % Allowance as a percentage of the ending loans in repayment (2) 0.28 % 1.83 % Allowance coverage of net charge-offs (annualized) 1.53 2.11 Ending total loans, gross $ 1,033,929 $ 13,848,262 Average loans in repayment (2) $ 795,452 $ 7,952,469 Ending loans in repayment (2) $ 795,665 $ 8,905,812 ____________ (1) Represents fair value adjustments on loans sold. (2) Loans in repayment include loans on which borrowers are making interest only or fixed payments, as well as loans that have entered full principal and interest repayment status after any applicable grace period. Allowance for Loan Losses Nine Months Ended September 30, 2015 FFELP Loans Private Education Loans Total Allowance for Loan Losses Beginning balance $ 5,268 $ 78,574 $ 83,842 Total provision 1,044 58,629 59,673 Net charge-offs: Charge-offs (2,142 ) (36,127 ) (38,269 ) Recoveries — 4,529 4,529 Net charge-offs (2,142 ) (31,598 ) (33,740 ) Loan sales (1) — (5,572 ) (5,572 ) Ending Balance $ 4,170 $ 100,033 $ 104,203 Allowance: Ending balance: individually evaluated for impairment $ — $ 43,001 $ 43,001 Ending balance: collectively evaluated for impairment $ 4,170 $ 57,032 $ 61,202 Loans: Ending balance: individually evaluated for impairment $ — $ 231,286 $ 231,286 Ending balance: collectively evaluated for impairment $ 1,143,595 $ 10,608,975 $ 11,752,570 Net charge-offs as a percentage of average loans in repayment (annualized) (2) 0.33 % 0.72 % Allowance as a percentage of the ending total loan balance 0.36 % 0.92 % Allowance as a percentage of the ending loans in repayment (2) 0.50 % 1.50 % Allowance coverage of net charge-offs (annualized) 1.46 2.37 Ending total loans, gross $ 1,143,595 $ 10,840,261 Average loans in repayment (2) $ 868,649 $ 5,848,345 Ending loans in repayment (2) $ 836,585 $ 6,657,228 ____________ (1) Represents fair value adjustments on loans sold. (2) Loans in repayment include loans on which borrowers are making interest only or fixed payments, as well as loans that have entered full principal and interest repayment status after any applicable grace period. Troubled Debt Restructurings (“TDRs”) All of our loans are collectively assessed for impairment, except for loans classified as TDRs (where we conduct individual assessments of impairment). We modify the terms of loans for certain borrowers when we believe such modifications may increase the ability and willingness of a borrower to make payments and thus increase the ultimate overall amount collected on a loan. These modifications generally take the form of a forbearance, a temporary interest rate reduction or an extended repayment plan. The majority of our loans that are considered TDRs involve a temporary forbearance of payments and do not change the contractual interest rate of the loan. Approximately 25 percent and 23 percent of the loans granted forbearance as of September 30, 2016 and December 31, 2015 , respectively, have been classified as TDRs due to their forbearance status. For additional information, see Note 6, “Allowance for Loan Losses” in our 2015 Form 10-K. Within the Private Education Loan portfolio, loans greater than 90 days past due are considered to be nonperforming. FFELP Loans are at least 97 percent guaranteed as to their principal and accrued interest by the federal government in the event of default and, therefore, we do not deem FFELP Loans as nonperforming from a credit risk perspective at any point in their life cycle prior to claim payment, and continue to accrue interest on those loans through the date of claim. At September 30, 2016 and December 31, 2015 , all of our TDR loans had a related allowance recorded. The following table provides the recorded investment, unpaid principal balance and related allowance for our TDR loans. Recorded Investment Unpaid Principal Balance Allowance September 30, 2016 TDR Loans $ 510,361 $ 503,632 $ 77,521 December 31, 2015 TDR Loans $ 269,628 $ 265,831 $ 43,480 The following table provides the average recorded investment and interest income recognized for our TDR loans. Three Months Ended 2016 2015 Average Recorded Investment Interest Income Recognized Average Recorded Investment Interest Income Recognized TDR Loans $ 454,395 $ 8,116 $ 210,039 $ 4,198 Nine Months Ended 2016 2015 Average Recorded Investment Interest Income Recognized Average Recorded Investment Interest Income Recognized TDR Loans $ 373,747 $ 20,396 $ 150,240 $ 9,314 The following table provides information regarding the loan status of TDR loans. September 30, December 31, 2016 2015 Balance % Balance % TDR loans in in-school/grace/deferment (1) $ 22,544 $ 6,869 TDR loans in forbearance (2) 72,386 43,756 TDR loans in repayment (3) and percentage of each status: Loans current 366,000 89.6 % 185,936 86.4 % Loans delinquent 31-60 days (4) 21,781 5.3 14,948 6.9 Loans delinquent 61-90 days (4) 13,411 3.3 9,239 4.3 Loans delinquent greater than 90 days (4) 7,510 1.8 5,083 2.4 Total TDR loans in repayment 408,702 100.0 % 215,206 100.0 % Total TDR loans, gross $ 503,632 $ 265,831 _____ (1) Deferment includes customers who have returned to school or are engaged in other permitted educational activities and are not yet required to make payments on the loans (e.g., residency periods for medical students or a grace period for bar exam preparation). (2) Loans for customers who have requested extension of grace period generally during employment transition or who have temporarily ceased making full payments due to hardship or other factors, consistent with established loan program servicing policies and procedures. (3) Loans in repayment include loans on which borrowers are making interest only or fixed payments, as well as loans that have entered full principal and interest repayment status after any applicable grace period. (4) The period of delinquency is based on the number of days scheduled payments are contractually past due. The following table provides the amount of modified loans (which includes forbearance and reductions in interest rates) that became TDRs in the periods presented. Additionally, for the periods presented, the table summarizes charge-offs occurring in the TDR portfolio, as well as TDRs for which a payment default occurred in the relevant period presented and within 12 months of the loan first being designated as a TDR. We define payment default as 60 days past due for this disclosure. Three Months Ended Three Months Ended Modified Loans (1) Charge-offs Payment- Default Modified Loans (1) Charge-offs Payment- Default TDR Loans $ 116,419 $ 5,925 $ 23,326 $ 49,975 $ 3,456 $ 16,719 Nine Months Ended Nine Months Ended Modified Loans (1) Charge-offs Payment- Default Modified Loans (1) Charge-offs Payment- Default TDR Loans $ 270,266 $ 16,357 $ 70,401 $ 189,066 $ 5,845 $ 29,895 _____ (1) Represents the principal balance of loans that have been modified during the period and resulted in a TDR. Key Credit Quality Indicators For Private Education Loans, the key credit quality indicators are FICO scores, the existence of a cosigner, the loan status and loan seasoning. The FICO scores are assessed at original approval and periodically refreshed/updated through the loan’s term. The following table highlights the gross principal balance of our Private Education Loan portfolio stratified by key credit quality indicators. Private Education Loans Credit Quality Indicators September 30, 2016 December 31, 2015 Credit Quality Indicators: Balance (1) % of Balance Balance (1) % of Balance Cosigners: With cosigner $ 12,456,310 90 % $ 9,515,136 90 % Without cosigner 1,391,952 10 1,081,301 10 Total $ 13,848,262 100 % $ 10,596,437 100 % FICO at Original Approval: Less than 670 $ 889,151 6 % $ 700,779 7 % 670-699 2,025,444 15 1,554,959 15 700-749 4,492,235 32 3,403,823 32 Greater than or equal to 750 6,441,432 47 4,936,876 46 Total $ 13,848,262 100 % $ 10,596,437 100 % Seasoning (2) : 1-12 payments $ 4,307,106 31 % $ 3,059,901 29 % 13-24 payments 2,398,396 17 2,096,412 20 25-36 payments 1,357,242 10 1,084,818 10 37-48 payments 630,420 4 513,125 5 More than 48 payments 492,157 4 414,217 4 Not yet in repayment 4,662,941 34 3,427,964 32 Total $ 13,848,262 100 % $ 10,596,437 100 % (1) Balance represents gross Private Education Loans. (2) Number of months in active repayment (whether interest only payment, fixed payment, or full principal and interest payment status) for which a scheduled payment was due. The following table provides information regarding the loan status of our Private Education Loans. Loans in repayment include loans making interest only or fixed payments, as well as loans that have entered full principal and interest repayment status after any applicable grace period. Private Education Loans September 30, December 31, 2016 2015 Balance % Balance % Loans in-school/grace/deferment (1) $ 4,662,941 $ 3,427,964 Loans in forbearance (2) 279,509 241,207 Loans in repayment and percentage of each status: Loans current 8,724,365 98.0 % 6,773,095 97.8 % Loans delinquent 31-60 days (3) 108,591 1.2 91,129 1.3 Loans delinquent 61-90 days (3) 51,029 0.6 42,048 0.6 Loans delinquent greater than 90 days (3) 21,827 0.2 20,994 0.3 Total Private Education Loans in repayment 8,905,812 100.0 % 6,927,266 100.0 % Total Private Education loans, gross 13,848,262 10,596,437 Private Education Loans deferred origination costs 40,327 27,884 Total Private Education Loans 13,888,589 10,624,321 Private Education Loans allowance for losses (162,630 ) (108,816 ) Private Education Loans, net $ 13,725,959 $ 10,515,505 Percentage of Private Education Loans in repayment 64.3 % 65.4 % Delinquencies as a percentage of Private Education Loans in repayment 2.0 % 2.2 % Loans in forbearance as a percentage of Private Education Loans in repayment and forbearance 3.0 % 3.4 % (1) Deferment includes customers who have returned to school or are engaged in other permitted educational activities and are not yet required to make payments on the loans (e.g., residency periods for medical students or a grace period for bar exam preparation). (2) Loans for customers who have requested extension of grace period generally during employment transition or who have temporarily ceased making full payments due to hardship or other factors, consistent with established loan program servicing policies and procedures. (3) The period of delinquency is based on the number of days scheduled payments are contractually past due. Accrued Interest Receivable The following table provides information regarding accrued interest receivable on our Private Education Loans. The table also discloses the amount of accrued interest on loans greater than 90 days past due as compared to our allowance for uncollectible interest. The allowance for uncollectible interest exceeds the amount of accrued interest on our 90 days past due Private Education Loan portfolio for all periods presented. Private Education Loan Accrued Interest Receivable Total Interest Receivable Greater Than 90 Days Past Due Allowance for Uncollectible Interest September 30, 2016 $ 773,967 $ 803 $ 3,562 December 31, 2015 $ 542,919 $ 791 $ 3,332

Deposits

Deposits	9 Months Ended
	Sep. 30, 2016
Banking and Thrift [Abstract]
Deposits	Deposits The following table summarizes total deposits at September 30, 2016 and December 31, 2015 . September 30, December 31, 2016 2015 Deposits - interest bearing $ 12,941,020 $ 11,487,006 Deposits - non-interest bearing 325 701 Total deposits $ 12,941,345 $ 11,487,707 Interest Bearing Interest bearing deposits as of September 30, 2016 and December 31, 2015 consisted of retail non-maturity savings deposits, retail and brokered non-maturity money market deposits (“MMDAs”) and brokered and retail certificates of deposit (“CDs”). Included in these accounts are what we consider to be core deposits from various sources. Our deposit products are serviced by third-party providers. Placement fees associated with the brokered CDs are amortized into interest expense using the effective interest rate method. We recognized placement fee expense of $ 2.6 million and $ 2.7 million in the three months ended September 30, 2016 and 2015, respectively, and placement fee expense of $7.8 million and $ 8.0 million in the nine months ended September 30, 2016 and 2015, respectively. Fees paid to third-party brokers related to brokered CDs were $ 1.1 million and $0.5 million for the three months ended September 30, 2016 and 2015, respectively, and $4.0 million and $0.5 million for the nine months ended September 30, 2016 and 2015, respectively. Interest bearing deposits at September 30, 2016 and December 31, 2015 are summarized as follows: September 30, 2016 December 31, 2015 Amount Qtr.-End Weighted Average Stated Rate (1) Amount Year-End Weighted Average Stated Rate (1) Money market $ 5,859,986 1.20 % $ 4,886,299 1.19 % Savings 660,099 0.82 669,254 0.82 Certificates of deposit 6,420,935 1.24 5,931,453 0.98 Deposits - interest bearing $ 12,941,020 $ 11,487,006 ____________ (1) Includes the effect of interest rate swaps in effective hedge relationships. As of September 30, 2016 and December 31, 2015 , there were $ 363.2 million and $709.9 million, respectively, of deposits exceeding Federal Deposit Insurance Corporation (“FDIC”) insurance limits. Accrued interest on deposits was $24.9 million and $15.7 million at September 30, 2016 and December 31, 2015 , respectively. Non-Interest Bearing Non-interest bearing deposits were $ 0.3 million and $ 0.7 million as of September 30, 2016 and December 31, 2015 , respectively. For both periods, these were comprised of money market accounts related to our Employee Stock Purchase Plan account.

Borrowings

Borrowings	9 Months Ended
	Sep. 30, 2016
Debt Disclosure [Abstract]
Borrowings	Borrowings Outstanding borrowings consist of secured borrowings issued through our term asset-backed securitization (“ABS”) program and our asset-backed commercial paper (“ABCP”) funding facility (the “ABCP Facility”). The following table summarizes our secured borrowings at September 30, 2016 and December 31, 2015. September 30, 2016 December 31, 2015 Short-Term Long-Term Total Short-Term Long-Term Total Secured borrowings: Private Education Loan term securitization $ — $ 1,577,689 $ 1,577,689 $ — $ 579,101 $ 579,101 ABCP Facility 350,000 — 350,000 500,175 — 500,175 Total $ 350,000 $ 1,577,689 $ 1,927,689 $ 500,175 $ 579,101 $ 1,079,276 Short-term Borrowings Asset-Backed Commercial Paper Funding Facility On December 19, 2014, we closed on a $ 750.0 million ABCP Facility. We retained a 5 percent or $ 37.5 million participation interest in the ABCP Facility, resulting in $ 712.5 million of funds available for us to draw under the ABCP Facility. During 2015, we incurred financing costs under the ABCP Facility of approximately 0.40 percent on average on unused borrowing capacity and approximately 3-month LIBOR plus 0.80 percent on outstandings under the ABCP Facility. On February 25, 2016, we amended and extended the maturity of our ABCP Facility. The amended ABCP Facility is a $ 750.0 million ABCP Facility, in which we no longer hold a participation interest. As a result, the full $ 750.0 million is available for us to draw. We hold 100 percent of the residual interest in the ABCP Facility trust. Under the amended ABCP Facility, we incur financing costs of between 0.35 percent and 0.45 percent on unused borrowing capacity and approximately 3‑month LIBOR plus 1.00 percent on outstandings. The amended ABCP Facility extends the revolving period, during which we may borrow, repay and reborrow funds, until February 23, 2017. The scheduled amortization period, during which amounts outstanding under the ABCP Facility must be repaid, ends on February 23, 2018 (or earlier, if certain material adverse events occur). At September 30, 2016 , $ 350 million was outstanding under the ABCP Facility. At September 30, 2016, $ 428.7 million of our Private Education Loans were encumbered to support outstandings under the ABCP Facility. Short-term borrowings have a remaining term to maturity of one year or less. The ABCP Facility’s contractual maturity is two years from the date of inception or renewal ( one year revolving period plus a one year amortization period); however, we classify advances under our ABCP Facility as short-term borrowings because it is our intention to repay those advances within one year. Long-term Borrowings On May 26, 2016, we executed our $ 551 million SMB Private Education Loan Trust 2016-A term ABS transaction, which was accounted for as an on-balance sheet secured financing. We retained a 100 percent or $ 50 million interest in the Class B notes and 100 percent of the residual certificates issued in the securitization. $501 million of Class A notes from the securitization were sold to third parties, raising $ 501 million of gross proceeds. The Class A notes had a weighted average life of 4.01 years and priced at a weighted average LIBOR equivalent cost of 1-month LIBOR plus 1.38 percent . At September 30, 2016 , $ 571 million of our Private Education Loans were encumbered as a result of this transaction. On July 21, 2016, we executed our $ 657 million SMB Private Education Loan Trust 2016-B term ABS transaction, which was accounted for as an on-balance sheet secured financing. We retained a 100 percent or $ 50 million interest in the Class B notes and 100 percent of the residual certificates issued in the securitization. $ 607 million of Class A notes from the securitization were sold to third parties, raising $ 607 million of gross proceeds. The Class A notes had a weighted average life of 4.01 years and priced at a weighted average LIBOR equivalent cost of 1-month LIBOR plus 1.36 percent . At September 30, 2016 , $ 692 million of our Private Education Loans were encumbered as a result of this transaction. Secured Financings at Issuance Issue Date Issued Total Issued Weighted Average Cost of Funds (1) Weighted Average Life (in years) Private Education: 2015-B July 2015 $ 630,800 1-month LIBOR plus 1.53% 4.82 Total notes issued in 2015 $ 630,800 Total loan and accrued interest amount securitized at inception in 2015 $ 745,580 2016-A May 2016 $ 501,000 1-month LIBOR plus 1.38% 4.01 2016-B July 2016 $ 607,000 1-month LIBOR plus 1.36% 4.01 Total notes issued in 2016 $ 1,108,000 Total loan and accrued interest amount securitized at inception in 2016 $ 1,364,481 ____________ (1) Represents LIBOR equivalent cost of funds for floating and fixed rate bonds, excluding issuance costs. Consolidated Funding Vehicles We consolidate our financing entities that are VIEs as a result of our being the entities’ primary beneficiary. As a result, these financing VIEs are accounted for as secured borrowings. We consolidate the following financing VIEs as of September 30, 2016 and December 31, 2015, respectively: September 30, 2016 Debt Outstanding Carrying Amount of Assets Securing Debt Outstanding Short-Term Long-Term Total Loans Restricted Cash Other Assets (1) Total Secured borrowings: Private Education Loan term securitization $ — $ 1,577,689 $ 1,577,689 $ 1,901,146 $ 27,597 $ 133,896 $ 2,062,639 ABCP Facility 350,000 — 350,000 428,706 6,682 29,413 464,801 Total $ 350,000 $ 1,577,689 $ 1,927,689 $ 2,329,852 $ 34,279 $ 163,309 $ 2,527,440 ____ (1) Other assets primarily represent accrued interest receivable. December 31, 2015 Debt Outstanding Carrying Amount of Assets Securing Debt Outstanding Short-Term Long-Term Total Loans Restricted Cash Other Assets (1) Total Secured borrowings: Private Education Loan term securitization $ — $ 579,101 $ 579,101 $ 687,298 $ 9,996 $ 45,566 $ 742,860 ABCP Facility 500,175 — 500,175 923,687 12,443 58,095 994,225 Total $ 500,175 $ 579,101 $ 1,079,276 $ 1,610,985 $ 22,439 $ 103,661 $ 1,737,085 ____ (1) Other assets primarily represent accrued interest receivable. Other Borrowing Sources We maintain discretionary uncommitted Federal Funds lines of credit with various correspondent banks, which totaled $100 million at September 30, 2016 . The interest rate we are charged on these lines of credit is priced at Fed Funds plus a spread at the time of borrowing, and is payable daily. We did not utilize these lines of credit in the three and nine months ended September 30, 2016 and in the year ended December 31, 2015 . We established an account at the Federal Reserve Bank (“FRB”) to meet eligibility requirements for access to the Primary Credit borrowing facility at the FRB’s Discount Window (the “Window”). The Primary Credit borrowing facility is a lending program available to depository institutions that are in generally sound financial condition. All borrowings at the Window must be fully collateralized. We can pledge to the FRB asset-backed and mortgage-backed securities, as well as FFELP Loans and Private Education Loans, as collateral for borrowings at the Window. Generally, collateral value is assigned based on the estimated fair value of the pledged assets. At September 30, 2016 and December 31, 2015 , the value of our pledged collateral at the FRB totaled $2.5 billion and $1.7 billion, respectively. The interest rate charged to us is the discount rate set by the FRB. We did not utilize this facility in the three and nine months ended September 30, 2016 and in the year ended December 31, 2015 .

Private Education Loan Term Sec

Private Education Loan Term Securitizations	9 Months Ended
	Sep. 30, 2016
Transfers and Servicing [Abstract]
Private Education Loan Term Securitizations	Private Education Loan Term Securitizations We securitize Private Education Loan assets by selling these assets to securitization trusts. If a transfer of loans qualifies as a sale, we derecognize the loan and recognize a gain or loss as the difference between compensation received and the carrying basis of the loans sold and liabilities retained. We recognize the results of a transfer of loans based upon the settlement date of the transaction. If we have a variable interest in a VIE (e.g., a securitization trust) and have determined that we are the primary beneficiary, then we will consolidate the VIE and the transfer is accounted for as a financing as opposed to a sale. On May 26, 2016, we executed a $ 551 million Private Education Loan Trust term ABS transaction that was accounted for as a secured financing. We retained a 100 percent or $ 50 million interest in the Class B notes and 100 percent of the residual certificates issued in the securitization. $501 million of Class A notes from the securitization were sold to third parties, raising $ 501 million of gross proceeds. At September 30, 2016 , $ 571 million of our Private Education Loans were encumbered as a result of this transaction. On July 21, 2016, we executed a $ 657 million Private Education Loan Trust term ABS transaction that was accounted for as a secured financing. We retained a 100 percent or $ 50 million interest in the Class B notes and 100 percent of the residual certificates issued in the securitization. $ 607 million of Class A notes from the securitization were sold to third parties, raising $ 607 million of gross proceeds. At September 30, 2016 , $ 692 million of our Private Education Loans were encumbered as a result of this transaction.

Derivative Financial Instrument

Derivative Financial Instruments	9 Months Ended
	Sep. 30, 2016
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Financial Instruments	Derivative Financial Instruments We maintain an overall interest rate risk management strategy that incorporates the use of derivative instruments to reduce the economic effect of interest rate changes. Our goal is to manage interest rate sensitivity by modifying the repricing frequency and underlying index characteristics of certain balance sheet liabilities so any adverse impacts related to movements in interest rates are managed within low to moderate limits. As a result of interest rate fluctuations, hedged liabilities will appreciate or depreciate in market value or create variability in cash flows. Income or loss on the derivative instruments linked to the hedged item will generally offset the effect of this unrealized appreciation or depreciation or volatility in cash flows for the period the item is being hedged. We view this strategy as a prudent management of interest rate risk. Please refer to Note 11, “Derivative Financial Instruments” in our 2015 Form 10-K for a full discussion of our risk management strategy. Although we use derivatives to reduce the risk of interest rate changes, the use of derivatives does expose us to both market and credit risk. Market risk is the chance of financial loss resulting from changes in interest rates and market liquidity. Credit risk is the risk that a counterparty will not perform its obligations under a contract and it is limited to the loss of the fair value gain in a derivative that the counterparty owes us less collateral held and plus collateral posted. When the fair value of a derivative contract less collateral held and plus collateral posted is negative, we owe the counterparty and, therefore, we have no credit risk exposure to the counterparty; however, the counterparty has exposure to us. We minimize the credit risk in derivative instruments by entering into transactions with highly-rated counterparties that are reviewed regularly by our Credit Department. We also maintain a policy of requiring that all derivative contracts be governed by an International Swaps and Derivatives Association, Inc. Master Agreement. Depending on the nature of the derivative transaction, bilateral collateral arrangements are required as well. When we have more than one outstanding derivative transaction with the counterparty, and there exists legally enforceable netting provisions with the counterparty (i.e., a legal right to offset receivable and payable derivative contracts), the “net” mark-to-market exposure, less collateral held and plus collateral posted, represents exposure with the counterparty. When there is a net negative exposure, we consider our exposure to the counterparty to be zero. Title VII of the Dodd-Frank Act requires all standardized derivatives, including most interest rate swaps, to be submitted for clearing to central counterparties to reduce counterparty risk. As of September 30, 2016 , $ 5.6 billion notional of our derivative contracts were cleared on the Chicago Mercantile Exchange and the London Clearing House. All derivative contracts cleared through an exchange require collateral to be exchanged based on the fair value of the derivative. Our exposure is limited to the value of the derivative contracts in a gain position less any collateral held and plus any collateral posted. When there is a net negative exposure, we consider our exposure to the counterparty to be zero. At September 30, 2016 and December 31, 2015, we had a net positive exposure (derivative gain positions to us, less collateral held by us and plus collateral posted with counterparties) related to derivatives of $ 47.6 million and $ 50.1 million, respectively. Summary of Derivative Financial Statement Impact The following tables summarize the fair values and notional amounts of all derivative instruments at September 30, 2016 and December 31, 2015 , and their impact on earnings and other comprehensive income for the three and nine months ended September 30, 2016 and 2015. Please refer to Note 11, “Derivative Financial Instruments” in our 2015 Form 10-K for a full discussion of cash flow hedges, fair value hedges, and trading activities. Impact of Derivatives on the Consolidated Balance Sheet Cash Flow Hedges Fair Value Hedges Trading Total September 30, December 31, September 30, December September 30, December September 30, December 2016 2015 2016 2015 2016 2015 2016 2015 Fair Values (1) Hedged Risk Exposure Derivative Assets: (2) Interest rate swaps Interest rate $ — $ — $ 42,996 $ 15,231 $ 414 $ 83 $ 43,410 $ 15,314 Derivative Liabilities: (2) Interest rate swaps Interest rate (52,197 ) (27,512 ) (187 ) (2,339 ) (194 ) (646 ) (52,578 ) (30,497 ) Total net derivatives $ (52,197 ) $ (27,512 ) $ 42,809 $ 12,892 $ 220 $ (563 ) $ (9,168 ) $ (15,183 ) ___________ (1) Fair values reported are exclusive of collateral held and pledged and accrued interest. Assets and liabilities are presented without consideration of master netting agreements. Derivatives are carried on the balance sheet based on net position by counterparty under master netting agreements, and classified in other assets or other liabilities depending on whether in a net positive or negative position. (2) The following table reconciles gross positions with the impact of master netting agreements to the balance sheet classification: Other Assets Other Liabilities September 30, December 31, September 30, December 31, 2016 2015 2016 2015 Gross position (1) $ 43,410 $ 15,314 $ (52,578 ) $ (30,497 ) Impact of master netting agreement (14,111 ) (9,278 ) 14,111 9,278 Derivative values with impact of master netting agreements (as carried on balance sheet) 29,299 6,036 (38,467 ) (21,219 ) Cash collateral (held) pledged (12,101 ) (1,070 ) 47,283 54,845 Net position $ 17,198 $ 4,966 $ 8,816 $ 33,626 __________ (1) Gross position amounts are exclusive of accrued interest. Cash Flow Fair Value Trading Total September 30, December 31, September 30, December September 30, December September 30, December 2016 2015 2016 2015 2016 2015 2016 2015 Notional Values Interest rate swaps $ 1,078,709 $ 1,109,933 $ 3,767,045 $ 3,080,167 $ 1,267,694 $ 1,305,757 $ 6,113,448 $ 5,495,857 Impact of Derivatives on the Consolidated Statements of Income Three Months Ended Nine Months Ended 2016 2015 2016 2015 Fair Value Hedges Interest rate swaps: Hedge ineffectiveness gains (losses) recorded in earnings (1) $ 3,199 $ (1,843 ) $ 2,000 $ (929 ) Realized gains recorded in interest expense 6,944 7,531 21,593 22,512 Total $ 10,143 $ 5,688 $ 23,593 $ 21,583 Cash Flow Hedges Interest rate swaps: Hedge ineffectiveness losses recorded in earnings (1) $ (843 ) $ (273 ) $ (1,524 ) $ (542 ) Realized losses recorded in interest expense (4,381 ) (5,411 ) (13,588 ) (16,157 ) Total $ (5,224 ) $ (5,684 ) $ (15,112 ) $ (16,699 ) Trading Interest rate swaps: Interest reclassification $ 537 $ 853 $ 1,897 $ 2,846 Change in fair value of future interest payments recorded in earnings (1,525 ) 716 783 2,972 Total (1) (988 ) 1,569 2,680 5,818 Total $ 3,931 $ 1,573 $ 11,161 $ 10,702 ________ (1) Amounts included in “gains on derivatives and hedging activities, net” in the consolidated statements of income. Impact of Derivatives on the Statements of Changes in Stockholders’ Equity Three Months Ended Nine Months Ended September 30, September 30, 2016 2015 2016 2015 Amount of gain (loss) recognized in other comprehensive income (loss) $ 4,943 $ (27,162 ) $ (37,370 ) $ (35,441 ) Less: amount of (loss) gain reclassified in interest expense (1) (4,381 ) 5,411 (13,588 ) 16,157 Total change in other comprehensive income (loss) for unrealized gains (losses) on derivatives, before income tax benefit $ 9,324 $ (21,751 ) $ (23,782 ) $ (19,284 ) ___________ (1) Amounts included in “realized losses recorded in interest expense” in the “Impact of Derivatives on the Consolidated Statements of Income” table. Cash Collateral Cash collateral held related to derivative exposure between the Company and its derivatives counterparties was $12.1 million and $1.1 million at September 30, 2016 and December 31, 2015 , respectively. Collateral held is recorded in “Other Liabilities” on the consolidated balance sheets. Cash collateral pledged related to derivative exposure between the Company and its derivatives counterparties was $47.3 million and $54.8 million at September 30, 2016 and December 31, 2015 , respectively. Collateral pledged is recorded in “Other interest-earning assets” on the consolidated balance sheets.

Stockholders' Equity

Stockholders' Equity	9 Months Ended
	Sep. 30, 2016
Equity [Abstract]
Stockholders' Equity	Stockholders’ Equity The following table summarizes our common share repurchases and issuances. Three Months Ended Nine Months Ended (Shares and per share amounts in actuals) 2016 2015 2016 2015 Shares repurchased related to employee stock-based compensation plans (1)(2) 371,165 136,173 1,763,092 2,900,266 Average purchase price per share $ 7.22 $ 8.88 $ 6.35 $ 9.76 Common shares issued (3) 561,100 361,779 3,727,574 5,569,853 __________________ (1) Comprised of shares withheld from stock option exercises and vesting of restricted stock for employees’ tax withholding obligations and shares tendered by employees to satisfy option exercise costs. (2) At the present time, we do not intend to initiate a publicly announced share repurchase program. (3) Common shares issued under our various compensation and benefit plans. The closing price of our common stock on September 30, 2016 was $ 7.47 .

Earnings per Common Share

Earnings per Common Share	9 Months Ended
	Sep. 30, 2016
Earnings Per Share [Abstract]
Earnings per Common Share	Earnings per Common Share Basic earnings per common share (“EPS”) are calculated using the weighted average number of shares of common stock outstanding during each period. A reconciliation of the numerators and denominators of the basic and diluted EPS calculations follows. Three Months Ended Nine Months Ended September 30, September 30, (In thousands, except per share data) 2016 2015 2016 2015 Numerator: Net income $ 56,965 $ 45,724 $ 180,085 $ 184,439 Preferred stock dividends 5,316 4,913 15,698 14,606 Net income attributable to SLM Corporation common stock $ 51,649 $ 40,811 $ 164,387 $ 169,833 Denominator: Weighted average shares used to compute basic EPS 428,077 426,019 427,711 425,384 Effect of dilutive securities: Dilutive effect of stock options, restricted stock and restricted stock units and Employee Stock Purchase Plan (“ESPP”) (1)(2) 5,446 6,528 4,368 7,147 Weighted average shares used to compute diluted EPS 433,523 432,547 432,079 432,531 Basic earnings per common share attributable to SLM Corporation $ 0.12 $ 0.10 $ 0.38 $ 0.40 Diluted earnings per common share attributable to SLM Corporation $ 0.12 $ 0.09 $ 0.38 $ 0.39 ________________ (1) Includes the potential dilutive effect of additional common shares that are issuable upon exercise of outstanding stock options, restricted stock, restricted stock units, and the outstanding commitment to issue shares under the ESPP, determined by the treasury stock method. (2) For the three months ended September 30, 2016 and 2015, securities covering approximately 1 million and 2 million shares, respectively, and for the nine months ended September 30, 2016 and 2015, securities covering approximately 1 million and 2 million shares, respectively, were outstanding but not included in the computation of diluted earnings per share because they were anti-dilutive.

Fair Value Measurements

Fair Value Measurements	9 Months Ended
	Sep. 30, 2016
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements We use estimates of fair value in applying various accounting standards for our financial statements. We categorize our fair value estimates based on a hierarchical framework associated with three levels of price transparency utilized in measuring financial instruments at fair value. For additional information regarding our policies for determining fair value and the hierarchical framework, see Note 2, “Significant Accounting Policies - Fair Value Measurement” in our 2015 Form 10-K. During the three and nine months ended September 30, 2016 , there were no significant transfers of financial instruments between levels or changes in our methodology or assumptions used to value our financial instruments. The following table summarizes the valuation of our financial instruments that are marked to fair value on a recurring basis. Fair Value Measurements on a Recurring Basis September 30, 2016 December 31, 2015 Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total Assets Mortgage-backed securities $ — $ 213,176 $ — $ 213,176 $ — $ 195,391 $ — $ 195,391 Derivative instruments — 43,410 — 43,410 — 15,314 — 15,314 Total $ — $ 256,586 $ — $ 256,586 $ — $ 210,705 $ — $ 210,705 Liabilities Derivative instruments $ — $ (52,578 ) $ — $ (52,578 ) $ — $ (30,497 ) $ — $ (30,497 ) Total $ — $ (52,578 ) $ — $ (52,578 ) $ — $ (30,497 ) $ — $ (30,497 ) The following table summarizes the fair values of our financial assets and liabilities, including derivative financial instruments. September 30, 2016 December 31, 2015 Fair Value Carrying Value Difference Fair Value Carrying Value Difference Earning assets Loans held for investment, net $ 16,130,066 $ 14,760,504 $ 1,369,562 $ 12,343,726 $ 11,630,591 $ 713,135 Cash and cash equivalents 1,454,938 1,454,938 — 2,416,219 2,416,219 — Available-for-sale investments 213,176 213,176 — 195,391 195,391 — Accrued interest receivable 805,647 805,647 — 564,496 564,496 — Tax indemnification receivable 276,543 276,543 — 186,076 186,076 — Derivative instruments 43,410 43,410 — 15,314 15,314 — Total earning assets $ 18,923,780 $ 17,554,218 $ 1,369,562 $ 15,721,222 $ 15,008,087 $ 713,135 Interest-bearing liabilities Money-market and savings accounts $ 6,520,085 $ 6,520,085 $ — $ 5,556,254 $ 5,556,254 $ — Certificates of deposit 6,445,848 6,420,935 (24,913 ) 5,928,450 5,931,453 3,003 Short-term borrowings 350,000 350,000 — 500,175 500,175 — Long-term borrowings 1,608,985 1,577,689 (31,296 ) 567,468 579,101 11,633 Accrued interest payable 26,587 26,587 — 16,385 16,385 — Derivative instruments 52,578 52,578 — 30,497 30,497 — Total interest-bearing liabilities $ 15,004,083 $ 14,947,874 $ (56,209 ) $ 12,599,229 $ 12,613,865 $ 14,636 Excess of net asset fair value over carrying value $ 1,313,353 $ 727,771 Please refer to Note 15, “Fair Value Measurements” in our 2015 Form 10-K for a full discussion of the methods and assumptions used to estimate the fair value of each class of financial instruments.

Arrangements with Navient Corpo

Arrangements with Navient Corporation	9 Months Ended
	Sep. 30, 2016
Related Party Transactions [Abstract]
Arrangements with Navient Corporation	Arrangements with Navient Corporation In connection with the separation of Navient from SLM in the Spin-Off, we entered into a separation and distribution agreement (the “Separation and Distribution Agreement”) and other ancillary agreements with Navient. Please refer to Note 16, “Arrangements with Navient Corporation” in our 2015 Form 10-K for a full discussion of these agreements. Amended Loan Participation and Purchase Agreement Prior to the Spin-Off, Sallie Mae Bank, a Utah industrial bank subsidiary of the Company (the “Bank”), sold substantially all its Private Education Loans to several former affiliates, now subsidiaries of Navient (collectively, the “Purchasers”), pursuant to a Loan Participation and Purchase Agreement. This agreement predated the Spin-Off, but was significantly amended and reduced in scope in connection with the Spin-Off. Post-Spin-Off, the Bank retains only the right to require the Purchasers to purchase loans (at fair value) for which the borrower also has a separate lending relationship with Navient (“Split Loans”) when the Split Loans either (1) are more than 90 days past due; (2) have been restructured; (3) have been granted a hardship forbearance or more than six months of administrative forbearance; or (4) have a borrower or cosigner who has filed for bankruptcy. At September 30, 2016 , we held approximately $71 million of Split Loans. During the three months ended September 30, 2016 , the Bank sold loans to the Purchasers in the amount of $ 3.6 million in principal and $ 0.1 million in accrued interest income. During the three months ended September 30, 2015 , the Bank sold loans to the Purchasers in the amount of $ 6.6 million in principal and $ 0.2 million in accrued interest income. During the nine months ended September 30, 2016 , the Bank sold loans to the Purchasers in the amount of $ 13.1 million in principal and $ 0.3 million in accrued interest income. During the nine months ended September 30, 2015 , the Bank sold loans to the Purchasers in the amount of $ 21.1 million in principal and $ 0.4 million in accrued interest income. There was no gain as a result of the loans sold to the Purchasers in the three and nine months ended September 30, 2016 and September 30, 2015 . Total write-downs to fair value for loans sold with a fair value lower than par totaled $1.4 million and $ 1.9 million in the three months ended September 30, 2016 and September 30, 2015 , respectively. Total write-downs to fair value for loans sold with a fair value lower than par totaled $5.0 million and $5.6 million in the nine months ended September 30, 2016 and September 30, 2015 , respectively. Navient is the servicer for all of these loans.

Regulatory Capital

Regulatory Capital	9 Months Ended
	Sep. 30, 2016
Banking and Thrift [Abstract]
Regulatory Capital	Regulatory Capital The Bank is subject to various regulatory capital requirements administered by federal and state banking authorities. Failure to meet minimum capital requirements can initiate certain mandatory and possibly additional discretionary actions by regulators that, if undertaken, could have a direct material adverse effect on our business, results of operation and financial condition. Under the Basel III capital framework (“U.S. Basel III”) and the regulatory framework for prompt corrective action, the Bank must meet specific capital standards that involve quantitative measures of its assets, liabilities and certain off-balance sheet items as calculated under regulatory accounting practices. The Bank’s capital amounts and its classification under the prompt corrective action framework are also subject to qualitative judgments by the regulators about components of capital, risk weightings and other factors. As of January 1, 2015, the Bank was required to report regulatory capital and ratios in accordance with U.S. Basel III. Among other things, U.S. Basel III establishes Common Equity Tier 1 as a new tier of capital, modifies methods for calculating risk-weighted assets, introduces a new capital conservation buffer, and revises the capital thresholds of the prompt corrective action framework, including the “well capitalized” standard. “Well capitalized” regulatory requirements are the quantitative measures established by regulation to ensure capital adequacy. To qualify as “well capitalized,” the Bank must maintain minimum amounts and ratios (set forth in the table below) of Common Equity Tier 1, Tier 1 and Total capital to risk-weighted assets and of Tier 1 capital to average assets. The following capital amounts and ratios are based upon the Bank’s assets. Actual “Well Capitalized” Regulatory Requirements Amount Ratio Amount Ratio As of September 30, 2016: Common Equity Tier 1 Capital (to Risk-Weighted Assets) $ 1,928,979 12.4 % $ 1,012,748 > 6.5 % Tier 1 Capital (to Risk-Weighted Assets) $ 1,928,979 12.4 % $ 1,246,459 > 8.0 % Total Capital (to Risk-Weighted Assets) $ 2,095,397 13.4 % $ 1,558,074 > 10.0 % Tier 1 Capital (to Average Assets) $ 1,928,979 11.6 % $ 828,962 > 5.0 % As of December 31, 2015: Common Equity Tier 1 Capital (to Risk-Weighted Assets) $ 1,734,315 14.4 % $ 781,638 > 6.5 % Tier 1 Capital (to Risk-Weighted Assets) $ 1,734,315 14.4 % $ 962,017 > 8.0 % Total Capital (to Risk-Weighted Assets) $ 1,848,528 15.4 % $ 1,202,521 > 10.0 % Tier 1 Capital (to Average Assets) $ 1,734,315 12.3 % $ 704,979 > 5.0 % Bank Dividends The Bank is chartered under the laws of the State of Utah and its deposits are insured by the FDIC. The Bank’s ability to pay dividends is subject to the laws of Utah and the regulations of the FDIC. Generally, under Utah’s industrial bank laws and regulations as well as FDIC regulations, the Bank may pay dividends from its net profits without regulatory approval if, following the payment of the dividend, the Bank’s capital and surplus would not be impaired. The Bank paid no dividends for the three and nine months ended September 30, 2016 and September 30, 2015 .

Commitments, Contingencies and

Commitments, Contingencies and Guarantees	9 Months Ended
	Sep. 30, 2016
Commitments and Contingencies Disclosure [Abstract]
Commitments, Contingencies and Guarantees	Commitments, Contingencies and Guarantees Commitments When we approve a Private Education Loan at the beginning of an academic year, that approval may cover the borrowing for the entire academic year. As such, we do not always disburse the full amount of the loan at the time of such approval, but instead have a commitment to fund a portion of the loan at a later date (usually at the start of the second semester or subsequent trimesters). At September 30, 2016 , we had $ 1.8 billion of outstanding contractual loan commitments which we expect to fund during the remainder of the 2016/2017 academic year. At September 30, 2016 , we had a $ 1.6 million reserve recorded in “Other Liabilities” to cover expected losses that we conclude are probable to occur during the one year loss emergence period on these unfunded commitments. Regulatory Matters At the time of this filing, the Bank remains subject to a Consent Order, Order to Pay Restitution and Order to Pay Civil Money Penalty dated May 13, 2014 issued by the FDIC (the “FDIC Consent Order”) and a Consent Order (the “DOJ Consent Order”) issued by the Department of Justice (the “DOJ”). On May 13, 2014, the Bank reached a settlement with the DOJ regarding compliance issues with the Servicemembers’ Civil Relief Act (“SCRA”). At the same time, the Bank reached a settlement with the FDIC regarding disclosures and assessments of certain late fees, as well as compliance with the SCRA. Under the FDIC Consent Order, the Bank paid $3.3 million in fines and oversaw the refund of up to $30 million in late fees, funded by Navient as required by the terms of the Separation and Distribution Agreement, assessed on loans owned or originated by the Bank since its inception in November 2005. The DOJ Consent Order was approved by the U.S. District Court for the District of Delaware on September 29, 2014. Under the DOJ Consent Order, Navient is solely responsible for reimbursing SCRA benefits and related compensation on behalf of both its subsidiary, Navient Solutions, Inc., and the Bank. We believe the Bank has complied with all the requirements of the FDIC Consent Order and the DOJ Consent Order. This includes implementing new SCRA policies, procedures and training, updated billing statement disclosures, steps to ensure its third-party service providers are also fully compliant in these regards, and overseeing Navient’s restitution responsibilities. Notwithstanding the assumption by the Consumer Financial Protection Bureau (the “CFPB”) of the role of the Bank’s primary consumer compliance regulator in January 2015, the FDIC will continue to monitor the Bank’s improved compliance management system, policies and procedures until it is satisfied the Bank has demonstrated its ability to sustain the enhancements and additions implemented in response to the FDIC Consent Order. Pursuant to the terms of the DOJ Consent Order, the Bank will remain subject to certain DOJ reporting and record-keeping requirements until September 29, 2018. In May 2014, the Bank received a Civil Investigative Demand (“CID”) from the CFPB as part of the CFPB’s separate investigation relating to customer complaints, fees and charges assessed in connection with the servicing of student loans and related collection practices of pre-Spin-Off SLM Corporation (“pre-Spin-Off SLM”) by entities now subsidiaries of Navient during a time period prior to the Spin-Off. Two state attorneys general have provided the Bank identical CIDs and others have become involved in the inquiry over time. To the extent requested, we have been cooperating fully with the CFPB and the attorneys general but are not in a position at this time to predict the duration or outcome of the investigation. Given the timeframe covered by this demand and the focus on practices and procedures previously conducted by Navient and its servicing subsidiaries, Navient is leading the response to this investigation and has accepted responsibility for all costs, expenses, losses or remediation that may arise from this investigation. Contingencies In the ordinary course of business, we and our subsidiaries are routinely defendants in or parties to pending and threatened legal actions and proceedings, including actions brought on behalf of various classes of claimants. These actions and proceedings may be based on alleged violations of consumer protection, securities, employment and other laws. In certain of these actions and proceedings, claims for substantial monetary damage may be asserted against us and our subsidiaries. It is common for the Company, our subsidiaries and affiliates to receive information and document requests and investigative demands from state attorneys general, legislative committees, and administrative agencies. These requests may be for informational or regulatory purposes and may relate to our business practices, the industries in which we operate, or other companies with whom we conduct business. Our practice has been and continues to be to cooperate with these bodies and be responsive to any such requests. We are required to establish reserves for litigation and regulatory matters where those matters present loss contingencies that are both probable and estimable. When loss contingencies are not both probable and estimable, we do not establish reserves. Based on current knowledge, management does not believe there are loss contingencies, if any, arising from pending investigations, litigation or regulatory matters for which reserves should be established.

Subsequent Event

Subsequent Event	9 Months Ended
	Sep. 30, 2016
Subsequent Events [Abstract]
Subsequent Event	Subsequent Event On October 12, 2016, we executed our $ 674 million SMB Private Education Loan Trust 2016-C term ABS transaction, which will be accounted for as an on-balance sheet secured financing. We sold $ 674 million of notes to third parties and retained a 100 percent interest in the residual certificates issued in the securitization, raising approximately $ 673 million of gross proceeds. This transaction will be reflected in our fourth quarter 2016 results.

Significant Accounting Polici23

Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2016
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying unaudited, consolidated financial statements of SLM Corporation (“Sallie Mae,” “SLM,” the “Company,” “we,” or “us”) have been prepared in accordance with generally accepted accounting principles in the United States of America (“GAAP”) for interim financial information. Accordingly, they do not include all the information and footnotes required by GAAP for complete consolidated financial statements. The consolidated financial statements include the accounts of SLM Corporation and its majority-owned and controlled subsidiaries after eliminating the effects of intercompany accounts and transactions. In the opinion of management, all adjustments considered necessary for a fair statement of the results for the interim periods have been included. The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying notes. Actual results could differ from those estimates. Operating results for the three and nine months ended September 30, 2016 are not necessarily indicative of the results for the year ending December 31, 2016 or for any other period. These unaudited financial statements should be read in conjunction with the audited financial statements and related notes included in our Annual Report on Form 10-K for the year ended December 31, 2015 (the “2015 Form 10-K”).
Consolidation	Consolidation The consolidated financial statements include the accounts of the Company and its majority-owned and controlled subsidiaries after eliminating the effects of intercompany accounts and transactions. We consolidate any variable interest entity (“VIE”) where we have determined we are the primary beneficiary. The primary beneficiary is the entity which has both: (1) the power to direct the activities of the VIE that most significantly impact the VIE’s economic performance and (2) the obligation to absorb losses or receive benefits of the entity that could potentially be significant to the VIE.
Loan Interest Income	Loan Interest Income For loans classified as “held for investment,” we recognize interest income as earned, adjusted for the amortization of deferred direct origination costs. This adjustment is recognized based upon the expected yield of the loan over its life after giving effect to prepayments and extensions. We consider our constant prepayment rate (“CPR”) estimates a significant accounting assumption used to measure the expected prepayment activity in our education loan portfolio. The estimates are based on a number of factors such as historical prepayment rates for loans with similar loan characteristics, assumptions about portfolio composition and loan terms, and the prepayment curve’s tendency to follow a ramp pattern (i.e., the prepayment rate typically increases during the in-school and early repayment periods, then stabilizes). The CPR measures the expected prepayment activity over the life of the loan and is applied as a flat-rate input assumption when used in forecasting. Our CPR estimates include the effect of voluntary prepayments, education loan defaults, and consolidation (if the loans are consolidated to third parties), all of which shorten the lives of loans. CPR estimates also consider the utilization of deferment, forbearance, and extended repayment plans, which lengthen the lives of loans. We regularly evaluate the assumptions used to estimate the CPRs. In instances where there are changes to the assumptions, amortization of deferred direct origination costs is adjusted on a cumulative basis to reflect the change since the origination of the loan. We also pay to the U.S. Department of Education (“ED”) an annual 105 basis point Consolidation Loan Rebate Fee on FFELP consolidation loans, which is netted against loan interest income. Additionally, interest earned on education loans reflects potential non-payment adjustments in accordance with our uncollectible interest recognition policy. We do not amortize any adjustments to the basis of education loans when they are classified as “held-for-sale.” We recognize certain fee income (primarily late fees) on education loans when earned according to the contractual provisions of the promissory notes, as well as our expectation of collectibility. Fee income is recorded when earned in “other non-interest income” in the accompanying consolidated statements of income.
Recently Issued but Not Yet Adopted Accounting Pronouncements	Recently Issued but Not Yet Adopted Accounting Pronouncements On February 25, 2016, the Financial Accounting Standards Board (the “FASB”) issued Accounting Standards Update (“ASU”) No. 2016-02, “Leases,” a comprehensive new lease standard which will supersede previous lease guidance. The standard requires a lessee to recognize in its balance sheet assets and liabilities related to long-term leases that were classified as operating leases under previous guidance. An asset will be recognized related to the right to use the underlying asset and a liability will be recognized related to the obligation to make lease payments over the term of the lease. The standard also requires expanded disclosures surrounding leases. The standard is effective for fiscal periods beginning after December 15, 2018, and requires modified retrospective adoption, with early adoption permitted. We are currently evaluating the impact of the adoption of this standard on our consolidated financial statements and related disclosures. On March 30, 2016, the FASB issued ASU No. 2016-09, “Compensation - Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting,” which amends the current stock compensation guidance. The amendments simplify the accounting for the taxes related to stock-based compensation, including adjustments to how excess tax benefits and a company’s payments for tax withholdings should be classified. The standard is effective for fiscal periods beginning after December 15, 2016, with early adoption permitted. We continue to evaluate the impact of the adoption of this standard on our consolidated financial statements, and at this time we expect the standard to result in immaterial volatility in earnings caused by the change in the treatment of the tax benefits or deficiencies related to share-based payments at settlement (or expiration) through “income tax expense” in our consolidated statements of income. On June 16, 2016, the FASB issued ASU No. 2016-13, “Financial Instruments—Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments,” which requires measurement and recognition of expected credit losses for financial assets held. Under this standard, we will be required to hold an allowance equal to the expected life-of-loan losses on our loan portfolio. The standard is effective for fiscal periods beginning after December 15, 2019. While we are currently evaluating the impact of our pending adoption of this standard on our consolidated financial statements, we expect the adoption to have a material impact on our consolidated financial statements and capital ratios.

Loans Held for Investment (Tabl

Loans Held for Investment (Tables)	9 Months Ended
	Sep. 30, 2016
Receivables [Abstract]
Loans held for investment	Loans held for investment are summarized as follows: September 30, December 31, 2016 2015 Private Education Loans $ 13,848,262 $ 10,596,437 Deferred origination costs 40,327 27,884 Allowance for loan losses (162,630 ) (108,816 ) Total Private Education Loans, net 13,725,959 10,515,505 FFELP Loans 1,033,929 1,115,663 Unamortized acquisition costs, net 2,825 3,114 Allowance for loan losses (2,209 ) (3,691 ) Total FFELP Loans, net 1,034,545 1,115,086 Loans held for investment, net $ 14,760,504 $ 11,630,591 The average balance and the respective weighted average interest rates of education loans in our portfolio are summarized as follows: Three Months Ended Nine Months Ended September 30, September 30, 2016 2015 2016 2015 Average Balance Weighted Average Interest Rate Average Balance Weighted Average Interest Rate Average Balance Weighted Average Interest Rate Average Balance Weighted Average Interest Rate Private Education Loans $ 12,881,890 8.00 % $ 9,869,025 7.87 % $ 12,307,932 8.00 % $ 9,563,290 7.96 % FFELP Loans 1,049,803 3.52 1,161,288 3.27 1,076,394 3.48 1,196,491 3.22 Total portfolio $ 13,931,693 $ 11,030,313 $ 13,384,326 $ 10,759,781

Allowance for Loan Losses (Tabl

Allowance for Loan Losses (Tables)	9 Months Ended
	Sep. 30, 2016
Receivables [Abstract]
Allowance for credit losses and recorded investments in loans	Allowance for Loan Losses Metrics Allowance for Loan Losses Three Months Ended September 30, 2016 FFELP Loans Private Education Loans Total Allowance for Loan Losses Beginning balance $ 2,297 $ 142,628 $ 144,925 Total provision 268 40,502 40,770 Net charge-offs: Charge-offs (356 ) (22,072 ) (22,428 ) Recoveries — 2,973 2,973 Net charge-offs (356 ) (19,099 ) (19,455 ) Loan sales (1) — (1,401 ) (1,401 ) Ending Balance $ 2,209 $ 162,630 $ 164,839 Allowance: Ending balance: individually evaluated for impairment $ — $ 77,521 $ 77,521 Ending balance: collectively evaluated for impairment $ 2,209 $ 85,109 $ 87,318 Loans: Ending balance: individually evaluated for impairment $ — $ 503,632 $ 503,632 Ending balance: collectively evaluated for impairment $ 1,033,929 $ 13,344,630 $ 14,378,559 Net charge-offs as a percentage of average loans in repayment (annualized) (2) 0.18 % 0.91 % Allowance as a percentage of the ending total loan balance 0.21 % 1.17 % Allowance as a percentage of the ending loans in repayment (2) 0.28 % 1.83 % Allowance coverage of net charge-offs (annualized) 1.55 2.13 Ending total loans, gross $ 1,033,929 $ 13,848,262 Average loans in repayment (2) $ 791,296 $ 8,420,625 Ending loans in repayment (2) $ 795,665 $ 8,905,812 ____________ (1) Represents fair value adjustments on loans sold. (2) Loans in repayment include loans on which borrowers are making interest only or fixed payments, as well as loans that have entered full principal and interest repayment status after any applicable grace period. Allowance for Loan Losses Three Months Ended September 30, 2015 FFELP Loans Private Education Loans Total Allowance for Loan Losses Beginning balance $ 4,556 $ 87,310 $ 91,866 Total provision 143 27,354 27,497 Net charge-offs: Charge-offs (529 ) (14,121 ) (14,650 ) Recoveries — 1,361 1,361 Net charge-offs (529 ) (12,760 ) (13,289 ) Loan sales (1) — (1,871 ) (1,871 ) Ending Balance $ 4,170 $ 100,033 $ 104,203 Allowance: Ending balance: individually evaluated for impairment $ — $ 43,001 $ 43,001 Ending balance: collectively evaluated for impairment $ 4,170 $ 57,032 $ 61,202 Loans: Ending balance: individually evaluated for impairment $ — $ 231,286 $ 231,286 Ending balance: collectively evaluated for impairment $ 1,143,595 $ 10,608,975 $ 11,752,570 Net charge-offs as a percentage of average loans in repayment (annualized) (2) 0.25 % 0.83 % Allowance as a percentage of the ending total loan balance 0.36 % 0.92 % Allowance as a percentage of the ending loans in repayment (2) 0.50 % 1.50 % Allowance coverage of net charge-offs (annualized) 1.97 1.96 Ending total loans, gross $ 1,143,595 $ 10,840,261 Average loans in repayment (2) $ 839,090 $ 6,118,678 Ending loans in repayment (2) $ 836,585 $ 6,657,228 ____________ (1) Represents fair value adjustments on loans sold. (2) Loans in repayment include loans on which borrowers are making interest only or fixed payments, as well as loans that have entered full principal and interest repayment status after any applicable grace period. Allowance for Loan Losses Nine Months Ended September 30, 2016 FFELP Loans Private Education Loans Total Allowance for Loan Losses Beginning balance $ 3,691 $ 108,816 $ 112,507 Total provision (396 ) 116,703 116,307 Net charge-offs: Charge-offs (1,086 ) (64,979 ) (66,065 ) Recoveries — 7,098 7,098 Net charge-offs (1,086 ) (57,881 ) (58,967 ) Loan sales (1) — (5,008 ) (5,008 ) Ending Balance $ 2,209 $ 162,630 $ 164,839 Allowance: Ending balance: individually evaluated for impairment $ — $ 77,521 $ 77,521 Ending balance: collectively evaluated for impairment $ 2,209 $ 85,109 $ 87,318 Loans: Ending balance: individually evaluated for impairment $ — $ 503,632 $ 503,632 Ending balance: collectively evaluated for impairment $ 1,033,929 $ 13,344,630 $ 14,378,559 Net charge-offs as a percentage of average loans in repayment (annualized) (2) 0.18 % 0.97 % Allowance as a percentage of the ending total loan balance 0.21 % 1.17 % Allowance as a percentage of the ending loans in repayment (2) 0.28 % 1.83 % Allowance coverage of net charge-offs (annualized) 1.53 2.11 Ending total loans, gross $ 1,033,929 $ 13,848,262 Average loans in repayment (2) $ 795,452 $ 7,952,469 Ending loans in repayment (2) $ 795,665 $ 8,905,812 ____________ (1) Represents fair value adjustments on loans sold. (2) Loans in repayment include loans on which borrowers are making interest only or fixed payments, as well as loans that have entered full principal and interest repayment status after any applicable grace period. Allowance for Loan Losses Nine Months Ended September 30, 2015 FFELP Loans Private Education Loans Total Allowance for Loan Losses Beginning balance $ 5,268 $ 78,574 $ 83,842 Total provision 1,044 58,629 59,673 Net charge-offs: Charge-offs (2,142 ) (36,127 ) (38,269 ) Recoveries — 4,529 4,529 Net charge-offs (2,142 ) (31,598 ) (33,740 ) Loan sales (1) — (5,572 ) (5,572 ) Ending Balance $ 4,170 $ 100,033 $ 104,203 Allowance: Ending balance: individually evaluated for impairment $ — $ 43,001 $ 43,001 Ending balance: collectively evaluated for impairment $ 4,170 $ 57,032 $ 61,202 Loans: Ending balance: individually evaluated for impairment $ — $ 231,286 $ 231,286 Ending balance: collectively evaluated for impairment $ 1,143,595 $ 10,608,975 $ 11,752,570 Net charge-offs as a percentage of average loans in repayment (annualized) (2) 0.33 % 0.72 % Allowance as a percentage of the ending total loan balance 0.36 % 0.92 % Allowance as a percentage of the ending loans in repayment (2) 0.50 % 1.50 % Allowance coverage of net charge-offs (annualized) 1.46 2.37 Ending total loans, gross $ 1,143,595 $ 10,840,261 Average loans in repayment (2) $ 868,649 $ 5,848,345 Ending loans in repayment (2) $ 836,585 $ 6,657,228 ____________ (1) Represents fair value adjustments on loans sold. (2) Loans in repayment include loans on which borrowers are making interest only or fixed payments, as well as loans that have entered full principal and interest repayment status after any applicable grace period.
Impaired financing receivables	The following table provides the recorded investment, unpaid principal balance and related allowance for our TDR loans. Recorded Investment Unpaid Principal Balance Allowance September 30, 2016 TDR Loans $ 510,361 $ 503,632 $ 77,521 December 31, 2015 TDR Loans $ 269,628 $ 265,831 $ 43,480
Average recorded investment and interest income recognized for troubled debt restructuring loans	The following table provides the average recorded investment and interest income recognized for our TDR loans. Three Months Ended 2016 2015 Average Recorded Investment Interest Income Recognized Average Recorded Investment Interest Income Recognized TDR Loans $ 454,395 $ 8,116 $ 210,039 $ 4,198 Nine Months Ended 2016 2015 Average Recorded Investment Interest Income Recognized Average Recorded Investment Interest Income Recognized TDR Loans $ 373,747 $ 20,396 $ 150,240 $ 9,314
Age analysis of past due loans delinquencies	The following table provides information regarding the loan status of our Private Education Loans. Loans in repayment include loans making interest only or fixed payments, as well as loans that have entered full principal and interest repayment status after any applicable grace period. Private Education Loans September 30, December 31, 2016 2015 Balance % Balance % Loans in-school/grace/deferment (1) $ 4,662,941 $ 3,427,964 Loans in forbearance (2) 279,509 241,207 Loans in repayment and percentage of each status: Loans current 8,724,365 98.0 % 6,773,095 97.8 % Loans delinquent 31-60 days (3) 108,591 1.2 91,129 1.3 Loans delinquent 61-90 days (3) 51,029 0.6 42,048 0.6 Loans delinquent greater than 90 days (3) 21,827 0.2 20,994 0.3 Total Private Education Loans in repayment 8,905,812 100.0 % 6,927,266 100.0 % Total Private Education loans, gross 13,848,262 10,596,437 Private Education Loans deferred origination costs 40,327 27,884 Total Private Education Loans 13,888,589 10,624,321 Private Education Loans allowance for losses (162,630 ) (108,816 ) Private Education Loans, net $ 13,725,959 $ 10,515,505 Percentage of Private Education Loans in repayment 64.3 % 65.4 % Delinquencies as a percentage of Private Education Loans in repayment 2.0 % 2.2 % Loans in forbearance as a percentage of Private Education Loans in repayment and forbearance 3.0 % 3.4 % (1) Deferment includes customers who have returned to school or are engaged in other permitted educational activities and are not yet required to make payments on the loans (e.g., residency periods for medical students or a grace period for bar exam preparation). (2) Loans for customers who have requested extension of grace period generally during employment transition or who have temporarily ceased making full payments due to hardship or other factors, consistent with established loan program servicing policies and procedures. (3) The period of delinquency is based on the number of days scheduled payments are contractually past due. The following table provides information regarding the loan status of TDR loans. September 30, December 31, 2016 2015 Balance % Balance % TDR loans in in-school/grace/deferment (1) $ 22,544 $ 6,869 TDR loans in forbearance (2) 72,386 43,756 TDR loans in repayment (3) and percentage of each status: Loans current 366,000 89.6 % 185,936 86.4 % Loans delinquent 31-60 days (4) 21,781 5.3 14,948 6.9 Loans delinquent 61-90 days (4) 13,411 3.3 9,239 4.3 Loans delinquent greater than 90 days (4) 7,510 1.8 5,083 2.4 Total TDR loans in repayment 408,702 100.0 % 215,206 100.0 % Total TDR loans, gross $ 503,632 $ 265,831 _____ (1) Deferment includes customers who have returned to school or are engaged in other permitted educational activities and are not yet required to make payments on the loans (e.g., residency periods for medical students or a grace period for bar exam preparation). (2) Loans for customers who have requested extension of grace period generally during employment transition or who have temporarily ceased making full payments due to hardship or other factors, consistent with established loan program servicing policies and procedures. (3) Loans in repayment include loans on which borrowers are making interest only or fixed payments, as well as loans that have entered full principal and interest repayment status after any applicable grace period. (4) The period of delinquency is based on the number of days scheduled payments are contractually past due.
Modified loans accounts for troubled debt restructuring	The following table provides the amount of modified loans (which includes forbearance and reductions in interest rates) that became TDRs in the periods presented. Additionally, for the periods presented, the table summarizes charge-offs occurring in the TDR portfolio, as well as TDRs for which a payment default occurred in the relevant period presented and within 12 months of the loan first being designated as a TDR. We define payment default as 60 days past due for this disclosure. Three Months Ended Three Months Ended Modified Loans (1) Charge-offs Payment- Default Modified Loans (1) Charge-offs Payment- Default TDR Loans $ 116,419 $ 5,925 $ 23,326 $ 49,975 $ 3,456 $ 16,719 Nine Months Ended Nine Months Ended Modified Loans (1) Charge-offs Payment- Default Modified Loans (1) Charge-offs Payment- Default TDR Loans $ 270,266 $ 16,357 $ 70,401 $ 189,066 $ 5,845 $ 29,895 _____ (1) Represents the principal balance of loans that have been modified during the period and resulted in a TDR.
Private education loan portfolio stratified by key credit quality indicators	The following table highlights the gross principal balance of our Private Education Loan portfolio stratified by key credit quality indicators. Private Education Loans Credit Quality Indicators September 30, 2016 December 31, 2015 Credit Quality Indicators: Balance (1) % of Balance Balance (1) % of Balance Cosigners: With cosigner $ 12,456,310 90 % $ 9,515,136 90 % Without cosigner 1,391,952 10 1,081,301 10 Total $ 13,848,262 100 % $ 10,596,437 100 % FICO at Original Approval: Less than 670 $ 889,151 6 % $ 700,779 7 % 670-699 2,025,444 15 1,554,959 15 700-749 4,492,235 32 3,403,823 32 Greater than or equal to 750 6,441,432 47 4,936,876 46 Total $ 13,848,262 100 % $ 10,596,437 100 % Seasoning (2) : 1-12 payments $ 4,307,106 31 % $ 3,059,901 29 % 13-24 payments 2,398,396 17 2,096,412 20 25-36 payments 1,357,242 10 1,084,818 10 37-48 payments 630,420 4 513,125 5 More than 48 payments 492,157 4 414,217 4 Not yet in repayment 4,662,941 34 3,427,964 32 Total $ 13,848,262 100 % $ 10,596,437 100 % (1) Balance represents gross Private Education Loans. (2) Number of months in active repayment (whether interest only payment, fixed payment, or full principal and interest payment status) for which a scheduled payment was due.
Accrued interest receivable	The following table provides information regarding accrued interest receivable on our Private Education Loans. The table also discloses the amount of accrued interest on loans greater than 90 days past due as compared to our allowance for uncollectible interest. The allowance for uncollectible interest exceeds the amount of accrued interest on our 90 days past due Private Education Loan portfolio for all periods presented. Private Education Loan Accrued Interest Receivable Total Interest Receivable Greater Than 90 Days Past Due Allowance for Uncollectible Interest September 30, 2016 $ 773,967 $ 803 $ 3,562 December 31, 2015 $ 542,919 $ 791 $ 3,332

Deposits (Tables)

Deposits (Tables)	9 Months Ended
	Sep. 30, 2016
Banking and Thrift [Abstract]
Schedule of deposits	The following table summarizes total deposits at September 30, 2016 and December 31, 2015 . September 30, December 31, 2016 2015 Deposits - interest bearing $ 12,941,020 $ 11,487,006 Deposits - non-interest bearing 325 701 Total deposits $ 12,941,345 $ 11,487,707
Interest bearing deposits	Interest bearing deposits at September 30, 2016 and December 31, 2015 are summarized as follows: September 30, 2016 December 31, 2015 Amount Qtr.-End Weighted Average Stated Rate (1) Amount Year-End Weighted Average Stated Rate (1) Money market $ 5,859,986 1.20 % $ 4,886,299 1.19 % Savings 660,099 0.82 669,254 0.82 Certificates of deposit 6,420,935 1.24 5,931,453 0.98 Deposits - interest bearing $ 12,941,020 $ 11,487,006 ____________ (1) Includes the effect of interest rate swaps in effective hedge relationships.

Borrowings (Tables)

Borrowings (Tables)	9 Months Ended
	Sep. 30, 2016
Debt Disclosure [Abstract]
Schedule of debt	The following table summarizes our secured borrowings at September 30, 2016 and December 31, 2015. September 30, 2016 December 31, 2015 Short-Term Long-Term Total Short-Term Long-Term Total Secured borrowings: Private Education Loan term securitization $ — $ 1,577,689 $ 1,577,689 $ — $ 579,101 $ 579,101 ABCP Facility 350,000 — 350,000 500,175 — 500,175 Total $ 350,000 $ 1,577,689 $ 1,927,689 $ 500,175 $ 579,101 $ 1,079,276
Schedule of securities financing transactions	Secured Financings at Issuance Issue Date Issued Total Issued Weighted Average Cost of Funds (1) Weighted Average Life (in years) Private Education: 2015-B July 2015 $ 630,800 1-month LIBOR plus 1.53% 4.82 Total notes issued in 2015 $ 630,800 Total loan and accrued interest amount securitized at inception in 2015 $ 745,580 2016-A May 2016 $ 501,000 1-month LIBOR plus 1.38% 4.01 2016-B July 2016 $ 607,000 1-month LIBOR plus 1.36% 4.01 Total notes issued in 2016 $ 1,108,000 Total loan and accrued interest amount securitized at inception in 2016 $ 1,364,481 ____________ (1) Represents LIBOR equivalent cost of funds for floating and fixed rate bonds, excluding issuance costs.
Schedule of variable interest entities	We consolidate the following financing VIEs as of September 30, 2016 and December 31, 2015, respectively: September 30, 2016 Debt Outstanding Carrying Amount of Assets Securing Debt Outstanding Short-Term Long-Term Total Loans Restricted Cash Other Assets (1) Total Secured borrowings: Private Education Loan term securitization $ — $ 1,577,689 $ 1,577,689 $ 1,901,146 $ 27,597 $ 133,896 $ 2,062,639 ABCP Facility 350,000 — 350,000 428,706 6,682 29,413 464,801 Total $ 350,000 $ 1,577,689 $ 1,927,689 $ 2,329,852 $ 34,279 $ 163,309 $ 2,527,440 ____ (1) Other assets primarily represent accrued interest receivable. December 31, 2015 Debt Outstanding Carrying Amount of Assets Securing Debt Outstanding Short-Term Long-Term Total Loans Restricted Cash Other Assets (1) Total Secured borrowings: Private Education Loan term securitization $ — $ 579,101 $ 579,101 $ 687,298 $ 9,996 $ 45,566 $ 742,860 ABCP Facility 500,175 — 500,175 923,687 12,443 58,095 994,225 Total $ 500,175 $ 579,101 $ 1,079,276 $ 1,610,985 $ 22,439 $ 103,661 $ 1,737,085 ____ (1) Other assets primarily represent accrued interest receivable.

Derivative Financial Instrume28

Derivative Financial Instruments (Tables)	9 Months Ended
	Sep. 30, 2016
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Impact of derivatives on the consolidated balance sheet	The following tables summarize the fair values and notional amounts of all derivative instruments at September 30, 2016 and December 31, 2015 , and their impact on earnings and other comprehensive income for the three and nine months ended September 30, 2016 and 2015. Please refer to Note 11, “Derivative Financial Instruments” in our 2015 Form 10-K for a full discussion of cash flow hedges, fair value hedges, and trading activities. Impact of Derivatives on the Consolidated Balance Sheet Cash Flow Hedges Fair Value Hedges Trading Total September 30, December 31, September 30, December September 30, December September 30, December 2016 2015 2016 2015 2016 2015 2016 2015 Fair Values (1) Hedged Risk Exposure Derivative Assets: (2) Interest rate swaps Interest rate $ — $ — $ 42,996 $ 15,231 $ 414 $ 83 $ 43,410 $ 15,314 Derivative Liabilities: (2) Interest rate swaps Interest rate (52,197 ) (27,512 ) (187 ) (2,339 ) (194 ) (646 ) (52,578 ) (30,497 ) Total net derivatives $ (52,197 ) $ (27,512 ) $ 42,809 $ 12,892 $ 220 $ (563 ) $ (9,168 ) $ (15,183 ) ___________ (1) Fair values reported are exclusive of collateral held and pledged and accrued interest. Assets and liabilities are presented without consideration of master netting agreements. Derivatives are carried on the balance sheet based on net position by counterparty under master netting agreements, and classified in other assets or other liabilities depending on whether in a net positive or negative position. (2) The following table reconciles gross positions with the impact of master netting agreements to the balance sheet classification: Other Assets Other Liabilities September 30, December 31, September 30, December 31, 2016 2015 2016 2015 Gross position (1) $ 43,410 $ 15,314 $ (52,578 ) $ (30,497 ) Impact of master netting agreement (14,111 ) (9,278 ) 14,111 9,278 Derivative values with impact of master netting agreements (as carried on balance sheet) 29,299 6,036 (38,467 ) (21,219 ) Cash collateral (held) pledged (12,101 ) (1,070 ) 47,283 54,845 Net position $ 17,198 $ 4,966 $ 8,816 $ 33,626 __________ (1) Gross position amounts are exclusive of accrued interest.
Offsetting assets	The following table reconciles gross positions with the impact of master netting agreements to the balance sheet classification: Other Assets Other Liabilities September 30, December 31, September 30, December 31, 2016 2015 2016 2015 Gross position (1) $ 43,410 $ 15,314 $ (52,578 ) $ (30,497 ) Impact of master netting agreement (14,111 ) (9,278 ) 14,111 9,278 Derivative values with impact of master netting agreements (as carried on balance sheet) 29,299 6,036 (38,467 ) (21,219 ) Cash collateral (held) pledged (12,101 ) (1,070 ) 47,283 54,845 Net position $ 17,198 $ 4,966 $ 8,816 $ 33,626 __________ (1) Gross position amounts are exclusive of accrued interest.
Offsetting liabilities	The following table reconciles gross positions with the impact of master netting agreements to the balance sheet classification: Other Assets Other Liabilities September 30, December 31, September 30, December 31, 2016 2015 2016 2015 Gross position (1) $ 43,410 $ 15,314 $ (52,578 ) $ (30,497 ) Impact of master netting agreement (14,111 ) (9,278 ) 14,111 9,278 Derivative values with impact of master netting agreements (as carried on balance sheet) 29,299 6,036 (38,467 ) (21,219 ) Cash collateral (held) pledged (12,101 ) (1,070 ) 47,283 54,845 Net position $ 17,198 $ 4,966 $ 8,816 $ 33,626 __________ (1) Gross position amounts are exclusive of accrued interest.
Schedule of notional amounts of outstanding derivative positions	Cash Flow Fair Value Trading Total September 30, December 31, September 30, December September 30, December September 30, December 2016 2015 2016 2015 2016 2015 2016 2015 Notional Values Interest rate swaps $ 1,078,709 $ 1,109,933 $ 3,767,045 $ 3,080,167 $ 1,267,694 $ 1,305,757 $ 6,113,448 $ 5,495,857
Derivative instruments, gain (loss)	Impact of Derivatives on the Consolidated Statements of Income Three Months Ended Nine Months Ended 2016 2015 2016 2015 Fair Value Hedges Interest rate swaps: Hedge ineffectiveness gains (losses) recorded in earnings (1) $ 3,199 $ (1,843 ) $ 2,000 $ (929 ) Realized gains recorded in interest expense 6,944 7,531 21,593 22,512 Total $ 10,143 $ 5,688 $ 23,593 $ 21,583 Cash Flow Hedges Interest rate swaps: Hedge ineffectiveness losses recorded in earnings (1) $ (843 ) $ (273 ) $ (1,524 ) $ (542 ) Realized losses recorded in interest expense (4,381 ) (5,411 ) (13,588 ) (16,157 ) Total $ (5,224 ) $ (5,684 ) $ (15,112 ) $ (16,699 ) Trading Interest rate swaps: Interest reclassification $ 537 $ 853 $ 1,897 $ 2,846 Change in fair value of future interest payments recorded in earnings (1,525 ) 716 783 2,972 Total (1) (988 ) 1,569 2,680 5,818 Total $ 3,931 $ 1,573 $ 11,161 $ 10,702 ________ (1) Amounts included in “gains on derivatives and hedging activities, net” in the consolidated statements of income.
Schedule of derivative instruments, effect on other comprehensive income (loss)	Impact of Derivatives on the Statements of Changes in Stockholders’ Equity Three Months Ended Nine Months Ended September 30, September 30, 2016 2015 2016 2015 Amount of gain (loss) recognized in other comprehensive income (loss) $ 4,943 $ (27,162 ) $ (37,370 ) $ (35,441 ) Less: amount of (loss) gain reclassified in interest expense (1) (4,381 ) 5,411 (13,588 ) 16,157 Total change in other comprehensive income (loss) for unrealized gains (losses) on derivatives, before income tax benefit $ 9,324 $ (21,751 ) $ (23,782 ) $ (19,284 ) ___________ (1) Amounts included in “realized losses recorded in interest expense” in the “Impact of Derivatives on the Consolidated Statements of Income” table.

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	9 Months Ended
	Sep. 30, 2016
Equity [Abstract]
Schedule of common share repurchases	The following table summarizes our common share repurchases and issuances. Three Months Ended Nine Months Ended (Shares and per share amounts in actuals) 2016 2015 2016 2015 Shares repurchased related to employee stock-based compensation plans (1)(2) 371,165 136,173 1,763,092 2,900,266 Average purchase price per share $ 7.22 $ 8.88 $ 6.35 $ 9.76 Common shares issued (3) 561,100 361,779 3,727,574 5,569,853 __________________ (1) Comprised of shares withheld from stock option exercises and vesting of restricted stock for employees’ tax withholding obligations and shares tendered by employees to satisfy option exercise costs. (2) At the present time, we do not intend to initiate a publicly announced share repurchase program. (3) Common shares issued under our various compensation and benefit plans.

Earnings per Common Share (Tabl

Earnings per Common Share (Tables)	9 Months Ended
	Sep. 30, 2016
Earnings Per Share [Abstract]
Schedule of earnings per share, basic and diluted	A reconciliation of the numerators and denominators of the basic and diluted EPS calculations follows. Three Months Ended Nine Months Ended September 30, September 30, (In thousands, except per share data) 2016 2015 2016 2015 Numerator: Net income $ 56,965 $ 45,724 $ 180,085 $ 184,439 Preferred stock dividends 5,316 4,913 15,698 14,606 Net income attributable to SLM Corporation common stock $ 51,649 $ 40,811 $ 164,387 $ 169,833 Denominator: Weighted average shares used to compute basic EPS 428,077 426,019 427,711 425,384 Effect of dilutive securities: Dilutive effect of stock options, restricted stock and restricted stock units and Employee Stock Purchase Plan (“ESPP”) (1)(2) 5,446 6,528 4,368 7,147 Weighted average shares used to compute diluted EPS 433,523 432,547 432,079 432,531 Basic earnings per common share attributable to SLM Corporation $ 0.12 $ 0.10 $ 0.38 $ 0.40 Diluted earnings per common share attributable to SLM Corporation $ 0.12 $ 0.09 $ 0.38 $ 0.39 ________________ (1) Includes the potential dilutive effect of additional common shares that are issuable upon exercise of outstanding stock options, restricted stock, restricted stock units, and the outstanding commitment to issue shares under the ESPP, determined by the treasury stock method. (2) For the three months ended September 30, 2016 and 2015, securities covering approximately 1 million and 2 million shares, respectively, and for the nine months ended September 30, 2016 and 2015, securities covering approximately 1 million and 2 million shares, respectively, were outstanding but not included in the computation of diluted earnings per share because they were anti-dilutive.

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	9 Months Ended
	Sep. 30, 2016
Fair Value Disclosures [Abstract]
Valuation of financial instruments that are marked-to-market on recurring basis	The following table summarizes the valuation of our financial instruments that are marked to fair value on a recurring basis. Fair Value Measurements on a Recurring Basis September 30, 2016 December 31, 2015 Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total Assets Mortgage-backed securities $ — $ 213,176 $ — $ 213,176 $ — $ 195,391 $ — $ 195,391 Derivative instruments — 43,410 — 43,410 — 15,314 — 15,314 Total $ — $ 256,586 $ — $ 256,586 $ — $ 210,705 $ — $ 210,705 Liabilities Derivative instruments $ — $ (52,578 ) $ — $ (52,578 ) $ — $ (30,497 ) $ — $ (30,497 ) Total $ — $ (52,578 ) $ — $ (52,578 ) $ — $ (30,497 ) $ — $ (30,497 )
Fair Values of financial assets and liabilities, including derivative financial instruments	The following table summarizes the fair values of our financial assets and liabilities, including derivative financial instruments. September 30, 2016 December 31, 2015 Fair Value Carrying Value Difference Fair Value Carrying Value Difference Earning assets Loans held for investment, net $ 16,130,066 $ 14,760,504 $ 1,369,562 $ 12,343,726 $ 11,630,591 $ 713,135 Cash and cash equivalents 1,454,938 1,454,938 — 2,416,219 2,416,219 — Available-for-sale investments 213,176 213,176 — 195,391 195,391 — Accrued interest receivable 805,647 805,647 — 564,496 564,496 — Tax indemnification receivable 276,543 276,543 — 186,076 186,076 — Derivative instruments 43,410 43,410 — 15,314 15,314 — Total earning assets $ 18,923,780 $ 17,554,218 $ 1,369,562 $ 15,721,222 $ 15,008,087 $ 713,135 Interest-bearing liabilities Money-market and savings accounts $ 6,520,085 $ 6,520,085 $ — $ 5,556,254 $ 5,556,254 $ — Certificates of deposit 6,445,848 6,420,935 (24,913 ) 5,928,450 5,931,453 3,003 Short-term borrowings 350,000 350,000 — 500,175 500,175 — Long-term borrowings 1,608,985 1,577,689 (31,296 ) 567,468 579,101 11,633 Accrued interest payable 26,587 26,587 — 16,385 16,385 — Derivative instruments 52,578 52,578 — 30,497 30,497 — Total interest-bearing liabilities $ 15,004,083 $ 14,947,874 $ (56,209 ) $ 12,599,229 $ 12,613,865 $ 14,636 Excess of net asset fair value over carrying value $ 1,313,353 $ 727,771

Regulatory Capital (Tables)

Regulatory Capital (Tables)	9 Months Ended
	Sep. 30, 2016
Banking and Thrift [Abstract]
Schedule of compliance with regulatory capital requirements under banking regulations	The following capital amounts and ratios are based upon the Bank’s assets. Actual “Well Capitalized” Regulatory Requirements Amount Ratio Amount Ratio As of September 30, 2016: Common Equity Tier 1 Capital (to Risk-Weighted Assets) $ 1,928,979 12.4 % $ 1,012,748 > 6.5 % Tier 1 Capital (to Risk-Weighted Assets) $ 1,928,979 12.4 % $ 1,246,459 > 8.0 % Total Capital (to Risk-Weighted Assets) $ 2,095,397 13.4 % $ 1,558,074 > 10.0 % Tier 1 Capital (to Average Assets) $ 1,928,979 11.6 % $ 828,962 > 5.0 % As of December 31, 2015: Common Equity Tier 1 Capital (to Risk-Weighted Assets) $ 1,734,315 14.4 % $ 781,638 > 6.5 % Tier 1 Capital (to Risk-Weighted Assets) $ 1,734,315 14.4 % $ 962,017 > 8.0 % Total Capital (to Risk-Weighted Assets) $ 1,848,528 15.4 % $ 1,202,521 > 10.0 % Tier 1 Capital (to Average Assets) $ 1,734,315 12.3 % $ 704,979 > 5.0 %

Significant Accounting Polices

Significant Accounting Polices - Narrative (Details) - USD ($) $ in Thousands	Apr. 30, 2014	Sep. 30, 2016	Sep. 30, 2015
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Income tax expense and other income		$ 120,987	$ 109,865
Consolidated loan rebate fee		1.05%
Additional Tax Positions
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Increase (Decrease) in tax receivable and income tax payable	$ 120,000
Income tax expense and other income	$ 9,000

Loans Held for Investment - Add

Loans Held for Investment - Additional Information (Detail)	9 Months Ended	12 Months Ended
	Sep. 30, 2016	Dec. 31, 2015	Jul. 01, 2006	Jun. 30, 2006	Sep. 30, 1993
Receivables [Abstract]
Percent of private loans indexed to LIBOR	81.00%
Tier 1 of government guarantee (in percentage)	97.00%		97.00%
Tier 2 of government guarantee (in percentage)				98.00%
Tier 3 of government guarantee (in percentage)					100.00%
Estimated weighted average life of student loans (in years)	6 years	6 years 2 months 12 days

Loans Held for Investment - Stu

Loans Held for Investment - Student Loan Portfolio by Program (Detail) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Receivables [Abstract]
Private Education Loans	$ 13,848,262	$ 10,596,437
Deferred origination costs	40,327	27,884
Allowance for loan losses	(162,630)	(108,816)
Total Private Education Loans, net	13,725,959	10,515,505
FFELP Loans	1,033,929	1,115,663
Unamortized acquisition costs, net	2,825	3,114
Allowance for loan losses	(2,209)	(3,691)
Total FFELP Loans, net	1,034,545	1,115,086
Loans held for investment, net	$ 14,760,504	$ 11,630,591

Loans Held for Investment - S36

Loans Held for Investment - Student Loan Portfolio Average Balances (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Receivables [Abstract]
Average Balance, Private Education Loans	$ 12,881,890	$ 9,869,025	$ 12,307,932	$ 9,563,290
Average Balance FFELP Loans	1,049,803	1,161,288	1,076,394	1,196,491
Average balance, Total portfolio	$ 13,931,693	$ 11,030,313	$ 13,384,326	$ 10,759,781
Weighted Average Interest Rate, Private Education Loans	8.00%	7.87%	8.00%	7.96%
Weighted Average Interest Rate FFELP loans	3.52%	3.27%	3.48%	3.22%

Allowance for Loan Losses - All

Allowance for Loan Losses - Allowance for Credit Losses and Recorded Investments in Loans (Detail) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016USD ($)charge_off	Sep. 30, 2015USD ($)charge_off	Sep. 30, 2016USD ($)charge_off	Sep. 30, 2015USD ($)charge_off
Allowance for Loan Losses
Beginning balance	$ 144,925	$ 91,866	$ 112,507	$ 83,842
Total provision	40,770	27,497	116,307	59,673
Net charge-offs:
Charge-offs	(22,428)	(14,650)	(66,065)	(38,269)
Recoveries	2,973	1,361	7,098	4,529
Net charge-offs	(19,455)	(13,289)	(58,967)	(33,740)
Loan sales	(1,401)	(1,871)	(5,008)	(5,572)
Ending Balance	164,839	104,203	164,839	104,203
Allowance:
Ending balance: individually evaluated for impairment	77,521	43,001	77,521	43,001
Ending balance: collectively evaluated for impairment	87,318	61,202	87,318	61,202
Loans:
Ending balance: individually evaluated for impairment	503,632	231,286	503,632	231,286
Ending balance: collectively evaluated for impairment	14,378,559	11,752,570	14,378,559	11,752,570
FFELP Loans
Allowance for Loan Losses
Beginning balance	2,297	4,556	3,691	5,268
Total provision	268	143	(396)	1,044
Net charge-offs:
Charge-offs	(356)	(529)	(1,086)	(2,142)
Recoveries	0	0	0	0
Net charge-offs	(356)	(529)	(1,086)	(2,142)
Loan sales	0	0	0	0
Ending Balance	2,209	4,170	2,209	4,170
Allowance:
Ending balance: individually evaluated for impairment	0	0	0	0
Ending balance: collectively evaluated for impairment	2,209	4,170	2,209	4,170
Loans:
Ending balance: individually evaluated for impairment	0	0	0	0
Ending balance: collectively evaluated for impairment	$ 1,033,929	$ 1,143,595	$ 1,033,929	$ 1,143,595
Net charge-offs as a percentage of average loans in repayment (annualized)	0.18%	0.25%	0.18%	0.33%
Allowance as a percentage of the ending total loan balance	0.21%	0.36%	0.21%	0.36%
Allowance as a percentage of the ending loans in repayment	0.28%	0.50%	0.28%	0.50%
Allowance coverage of net charge-offs (annualized) | charge_off	1.55	1.97	1.53	1.46
Ending total loans, gross	$ 1,033,929	$ 1,143,595	$ 1,033,929	$ 1,143,595
Average loans in repayment	791,296	839,090	795,452	868,649
Ending loans in repayment	795,665	836,585	795,665	836,585
Private Education Loans
Allowance for Loan Losses
Beginning balance	142,628	87,310	108,816	78,574
Total provision	40,502	27,354	116,703	58,629
Net charge-offs:
Charge-offs	(22,072)	(14,121)	(64,979)	(36,127)
Recoveries	2,973	1,361	7,098	4,529
Net charge-offs	(19,099)	(12,760)	(57,881)	(31,598)
Loan sales	(1,401)	(1,871)	(5,008)	(5,572)
Ending Balance	162,630	100,033	162,630	100,033
Allowance:
Ending balance: individually evaluated for impairment	77,521	43,001	77,521	43,001
Ending balance: collectively evaluated for impairment	85,109	57,032	85,109	57,032
Loans:
Ending balance: individually evaluated for impairment	503,632	231,286	503,632	231,286
Ending balance: collectively evaluated for impairment	$ 13,344,630	$ 10,608,975	$ 13,344,630	$ 10,608,975
Net charge-offs as a percentage of average loans in repayment (annualized)	0.91%	0.83%	0.97%	0.72%
Allowance as a percentage of the ending total loan balance	1.17%	0.92%	1.17%	0.92%
Allowance as a percentage of the ending loans in repayment	1.83%	1.50%	1.83%	1.50%
Allowance coverage of net charge-offs (annualized) | charge_off	2.13	1.96	2.11	2.37
Ending total loans, gross	$ 13,848,262	$ 10,840,261	$ 13,848,262	$ 10,840,261
Average loans in repayment	8,420,625	6,118,678	7,952,469	5,848,345
Ending loans in repayment	$ 8,905,812	$ 6,657,228	$ 8,905,812	$ 6,657,228

Allowance for Loan Losses - Add

Allowance for Loan Losses - Additional Information (Detail)	9 Months Ended
	Sep. 30, 2016	Dec. 31, 2015	Jul. 01, 2006
Receivables [Abstract]
Percentage of loans granted forbearance qualified as TDR	25.00%	23.00%
Criteria for loans to be considered as nonperforming	90 days
Tier 1 of government guarantee (at least) (in percentage)	97.00%		97.00%
TDR payment default period	60 days
Period of loans past due that have accrued interest	90 days

Allowance for Loan Losses - Rec

Allowance for Loan Losses - Recorded Investment, Unpaid Principal Balance and Related Allowance for TDR Loans (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Receivables [Abstract]
Recorded Investment	$ 510,361	$ 269,628
Unpaid Principal Balance	503,632	265,831
Allowance	$ 77,521	$ 43,480

Allowance for Loan Losses - Ave

Allowance for Loan Losses - Average Recorded Investment and Interest Income Recognized for TDR (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Receivables [Abstract]
Average Recorded Investment	$ 454,395	$ 210,039	$ 373,747	$ 150,240
Interest Income Recognized	$ 8,116	$ 4,198	$ 20,396	$ 9,314

Allowance for Loan Losses - Loa

Allowance for Loan Losses - Loan Status and Aging of Past Due TDR Loans (Details) - Troubled Debt Restructured Loans - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2016	Dec. 31, 2015
Accounts, Notes, Loans and Financing Receivable [Line Items]
TDR loans in in-school/grace/deferment	$ 22,544	$ 6,869
TDR loans in forbearance	72,386	43,756
TDR loans in repayment and percentage of each status:
Loans current	366,000	185,936
Total TDR loans in repayment	408,702	215,206
Total TDR loans, gross	$ 503,632	$ 265,831
Loans current (as a percentage)	89.60%	86.40%
Total TDR loans in repayment, in percentage	100.00%	100.00%
Loans delinquent 31-60 days
TDR loans in repayment and percentage of each status:
Loans delinquent	$ 21,781	$ 14,948
Loans delinquent (as a percentage)	5.30%	6.90%
Loans delinquent 61-90 days
TDR loans in repayment and percentage of each status:
Loans delinquent	$ 13,411	$ 9,239
Loans delinquent (as a percentage)	3.30%	4.30%
Loans delinquent greater than 90 days
TDR loans in repayment and percentage of each status:
Loans delinquent	$ 7,510	$ 5,083
Loans delinquent (as a percentage)	1.80%	2.40%

Allowance for Loan Losses - Mod

Allowance for Loan Losses - Modified Loan Accounts for TDR (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Receivables [Abstract]
Modified Loans	$ 116,419	$ 49,975	$ 270,266	$ 189,066
Charge-offs	5,925	3,456	16,357	5,845
Payment-Default	$ 23,326	$ 16,719	$ 70,401	$ 29,895

Allowance for Loan Losses - Pri

Allowance for Loan Losses - Private Education Loan Portfolio Stratified by Key Credit Quality Indicators (Detail) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 13,848,262	$ 10,596,437
Private Education Loans | Cosigners
Accounts, Notes, Loans and Financing Receivable [Line Items]
Private Education Loans with cosigner	12,456,310	9,515,136
Private Education Loans without cosigner	1,391,952	1,081,301
Total	$ 13,848,262	$ 10,596,437
Private Education Loans with cosigner in percent	90.00%	90.00%
Private Education Loans without cosigner in percent	10.00%	10.00%
Total in percent	100.00%	100.00%
Private Education Loans | FICO at Original Approval
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 13,848,262	$ 10,596,437
Total in percent	100.00%	100.00%
Private Education Loans | Seasoning
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 13,848,262	$ 10,596,437
Total in percent	100.00%	100.00%
Seasoning - based on monthly scheduled payments due from 1-12 payments	$ 4,307,106	$ 3,059,901
Seasoning - based on monthly scheduled payments due from 13-24 payments	2,398,396	2,096,412
Seasoning - based on monthly scheduled payments due from 25-36 payments	1,357,242	1,084,818
Seasoning - based on monthly scheduled payments due from 37-48 payments	630,420	513,125
Seasoning - based on monthly scheduled payments due from more than 48 payments	492,157	414,217
Seasoning - based on monthly scheduled payments due from not yet in repayment	$ 4,662,941	$ 3,427,964
Seasoning based on monthly scheduled payments due from 1-12 payments, in percent	31.00%	29.00%
Seasoning based on monthly scheduled payments due from 13 - 24 payments, in percent	17.00%	20.00%
Seasoning based on monthly scheduled payments due from 25 - 36 payments, in percent	10.00%	10.00%
Seasoning based on monthly scheduled payments due from 37 - 48 payments, in percent	4.00%	5.00%
Seasoning based on monthly scheduled payments due from more than 48 payments, in percent	4.00%	4.00%
Seasoning - based on monthly scheduled payments due from not yet in repayment, in percent	34.00%	32.00%
FICO score less than 670 | Private Education Loans | FICO at Original Approval
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 889,151	$ 700,779
Total in percent	6.00%	7.00%
FICO score 670-699 | Private Education Loans | FICO at Original Approval
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 2,025,444	$ 1,554,959
Total in percent	15.00%	15.00%
FICO score 700-749 | Private Education Loans | FICO at Original Approval
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 4,492,235	$ 3,403,823
Total in percent	32.00%	32.00%
FICO score greater than or equal to 750 | Private Education Loans | FICO at Original Approval
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 6,441,432	$ 4,936,876
Total in percent	47.00%	46.00%

Allowance for Loan Losses - Age

Allowance for Loan Losses - Age Analysis of Past Due Loans Delinquencies (Detail) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2016	Dec. 31, 2015	Jun. 30, 2016	Sep. 30, 2015	Jun. 30, 2015	Dec. 31, 2014
Loans in repayment and percentage of each status:
Private Education Loans allowance for losses	$ (164,839)	$ (112,507)	$ (144,925)	$ (104,203)	$ (91,866)	$ (83,842)
Private Education Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans in-school/grace/deferment	4,662,941	3,427,964
Loans in forbearance	279,509	241,207
Loans in repayment and percentage of each status:
Loans current	8,724,365	6,773,095
Total Private Education Loans in repayment	8,905,812	6,927,266
Total Private Education loans, gross	13,848,262	10,596,437
Private Education Loans deferred origination costs	40,327	27,884
Total Private Education Loans	13,888,589	10,624,321
Private Education Loans allowance for losses	(162,630)	(108,816)	$ (142,628)	$ (100,033)	$ (87,310)	$ (78,574)
Private Education Loans, net	$ 13,725,959	$ 10,515,505
Loans current (as a percentage)	98.00%	97.80%
Total Private Education Loans in repayment (as a percentage)	100.00%	100.00%
Percentage of Private Education Loans in repayment (as a percentage)	64.30%	65.40%
Delinquencies as a percentage of Private Education Loans in repayment (as a percentage)	2.00%	2.20%
Loans in forbearance as a percentage of Private Education Loans in repayment and forbearance (as a percentage)	3.00%	3.40%
Loans delinquent 31-60 days | Private Education Loans
Loans in repayment and percentage of each status:
Loans delinquent	$ 108,591	$ 91,129
Loans delinquent (as a percentage)	1.20%	1.30%
Loans delinquent 61-90 days | Private Education Loans
Loans in repayment and percentage of each status:
Loans delinquent	$ 51,029	$ 42,048
Loans delinquent (as a percentage)	0.60%	0.60%
Loans delinquent greater than 90 days | Private Education Loans
Loans in repayment and percentage of each status:
Loans delinquent	$ 21,827	$ 20,994
Loans delinquent (as a percentage)	0.20%	0.30%

Allowance for Loan Losses - Acc

Allowance for Loan Losses - Accrued Interest Receivable (Detail) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Receivables [Abstract]
Total Interest Receivable	$ 773,967	$ 542,919
Greater Than 90 Days Past Due	803	791
Allowance for Uncollectible Interest	$ 3,562	$ 3,332

Deposits - Summary (Details)

Deposits - Summary (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Banking and Thrift [Abstract]
Deposits - interest bearing	$ 12,941,020	$ 11,487,006
Deposits - non-interest bearing	325	701
Total deposits	$ 12,941,345	$ 11,487,707

Deposits - Additional Informati

Deposits - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Banking and Thrift [Abstract]
Brokered deposit placement fee	$ 2,600	$ 2,700	$ 7,800	$ 8,000
Third party broker fees paid	1,100	$ 500	4,000	$ 500
Deposits exceeding FDIC insurance limits	363,200		363,200		$ 709,900
Accrued interest on deposits	24,900		24,900		15,700
Deposits - non-interest bearing	$ 325		$ 325		$ 701

Deposits - Interest Bearing Dep

Deposits - Interest Bearing Deposits (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Amount
Money market	$ 5,859,986	$ 4,886,299
Savings	660,099	669,254
Certificates of deposit	6,420,935	5,931,453
Deposits - interest bearing	$ 12,941,020	$ 11,487,006
Weighted Average Stated Rate
Money market	1.20%	1.19%
Savings	0.82%	0.82%
Certificates of deposit	1.24%	0.98%

Borrowings - Company Borrowings

Borrowings - Company Borrowings (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Short Term	$ 350,000	$ 500,175
Long Term	1,577,689	579,101
Total	1,927,689	1,079,276
Private Education Loan securitization
Debt Instrument [Line Items]
Short Term	0	0
Long Term	1,577,689	579,101
Total	1,577,689	579,101
ABCP borrowings
Debt Instrument [Line Items]
Short Term	350,000	500,175
Long Term	0	0
Total	$ 350,000	$ 500,175

Borrowings - Additional Informa

Borrowings - Additional Information (Details) - USD ($)	Jul. 21, 2016	May 26, 2016	Feb. 25, 2016	Sep. 30, 2016	Dec. 31, 2015	Dec. 19, 2014
Line of Credit Facility [Line Items]
Short-term borrowings				$ 350,000,000	$ 500,175,000
Estimated weighted average life of student loans (in years)				6 years	6 years 2 months 12 days
Uncommitted federal funds				$ 100,000,000
Lendable value of collateral				2,500,000,000	$ 1,700,000,000
ABCP borrowings
Line of Credit Facility [Line Items]
Short-term borrowings				350,000,000	$ 500,175,000
Loans pledged as collateral				$ 428,700,000
Contractual maturity				2 years
Contractual maturity term, revolving period				1 year
Contractual maturity term, amortization period				1 year
ABCP borrowings | Commercial Paper
Line of Credit Facility [Line Items]
Private asset backed commercial paper education loan funding facility			$ 750,000,000			$ 750,000,000
Ownership interest percentage in loan facility						5.00%
Required ownership interest						$ 37,500,000
Funds available for Private Education Loan originations						$ 712,500,000
Financing cost percentage of unused borrowing capacity					0.40%
Ownership interest percentage				100.00%
Private Education Loans
Line of Credit Facility [Line Items]
Total loan amount securitized at inception for the 2016 on-balance sheet term securitization	$ 657,000,000	$ 551,000,000
Proceeds from loan securitization sold to third parties	$ 607,000,000	$ 501,000,000
Class B Notes
Line of Credit Facility [Line Items]
Ownership interest percentage	100.00%	100.00%
Amount of ownership interest in loan securitization	$ 50,000,000	$ 50,000,000
Residual Certificates
Line of Credit Facility [Line Items]
Ownership interest percentage	100.00%	100.00%
Class A Notes
Line of Credit Facility [Line Items]
Amount of loan securitization sold to third parties	$ 607,000,000	$ 501,000,000
Proceeds from loan securitization sold to third parties	$ 607,000,000	$ 501,000,000
Estimated weighted average life of student loans (in years)	4 years 3 days	4 years 3 days
Private Education Loans Issuance 2016-A
Line of Credit Facility [Line Items]
Loans pledged as collateral				$ 571,000,000
Private Education Loans Issuance 2016-B
Line of Credit Facility [Line Items]
Loans pledged as collateral				$ 692,000,000
LIBOR | ABCP borrowings | Commercial Paper
Line of Credit Facility [Line Items]
Basis spread on variable rate			1.00%		0.80%
LIBOR | Class A Notes
Line of Credit Facility [Line Items]
Basis spread on variable rate	1.36%	1.38%
Minimum | ABCP borrowings | Commercial Paper
Line of Credit Facility [Line Items]
Financing cost percentage of unused borrowing capacity			0.35%
Maximum | ABCP borrowings | Commercial Paper
Line of Credit Facility [Line Items]
Financing cost percentage of unused borrowing capacity			0.45%

Borrowings - Securitizations (D

Borrowings - Securitizations (Details) - USD ($)	Jul. 31, 2016	May 31, 2016	Jul. 31, 2015	Sep. 30, 2016	Dec. 31, 2015
Securities Financing Transaction [Line Items]
Total bonds issued				$ 1,108,000,000	$ 630,800,000
Total loan and accrued interest amount securitized at inception on-balance sheet term securitization		$ 1,364,481,000	$ 745,580,000
2015-B
Securities Financing Transaction [Line Items]
Total bonds issued			$ 630,800,000
Weighted Average Life (in years)			4 years 9 months 26 days
2016-A
Securities Financing Transaction [Line Items]
Total bonds issued		$ 501,000,000
Weighted Average Life (in years)		4 years 3 days
2016-B
Securities Financing Transaction [Line Items]
Total bonds issued	$ 607,000,000
Weighted Average Life (in years)	4 years 3 days
LIBOR | 2015-B
Securities Financing Transaction [Line Items]
Basis spread on variable rate			1.53%
LIBOR | 2016-A
Securities Financing Transaction [Line Items]
Basis spread on variable rate		1.38%
LIBOR | 2016-B
Securities Financing Transaction [Line Items]
Basis spread on variable rate	1.36%

Borrowings - Financing VIEs (De

Borrowings - Financing VIEs (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Debt Outstanding
Short Term	$ 350,000	$ 500,175
Long Term	1,577,689	579,101
Total	1,927,689	1,079,276
Carrying Amount of Assets Securing Debt Outstanding
Restricted Cash	38,256	27,980
Other Assets	62,545	57,227
Private Education Loan securitization
Debt Outstanding
Short Term	0	0
Long Term	1,577,689	579,101
Total	1,577,689	579,101
ABCP Facility
Debt Outstanding
Short Term	350,000	500,175
Long Term	0	0
Total	350,000	500,175
Variable Interest Entity, Primary Beneficiary
Debt Outstanding
Short Term	350,000	500,175
Long Term	1,577,689	579,101
Total	1,927,689	1,079,276
Carrying Amount of Assets Securing Debt Outstanding
Loans	2,329,852	1,610,985
Restricted Cash	34,279	22,439
Other Assets	163,309	103,661
Total	2,527,440	1,737,085
Variable Interest Entity, Primary Beneficiary | Private Education Loan securitization
Debt Outstanding
Short Term	0	0
Long Term	1,577,689	579,101
Total	1,577,689	579,101
Carrying Amount of Assets Securing Debt Outstanding
Loans	1,901,146	687,298
Restricted Cash	27,597	9,996
Other Assets	133,896	45,566
Total	2,062,639	742,860
Variable Interest Entity, Primary Beneficiary | ABCP Facility
Debt Outstanding
Short Term	350,000	500,175
Long Term	0	0
Total	350,000	500,175
Carrying Amount of Assets Securing Debt Outstanding
Loans	428,706	923,687
Restricted Cash	6,682	12,443
Other Assets	29,413	58,095
Total	$ 464,801	$ 994,225

Private Education Loan Term S53

Private Education Loan Term Securitizations (Details) - USD ($) $ in Millions	Jul. 21, 2016	May 26, 2016	Sep. 30, 2016
Private Education Loans
Securitization or Asset-backed Financing Arrangement, Financial Asset for which Transfer is Accounted as Sale [Line Items]
Private education loan term accounted for as a secured financing	$ 657	$ 551
Proceeds from loan securitization sold to third parties	$ 607	$ 501
Class B Notes
Securitization or Asset-backed Financing Arrangement, Financial Asset for which Transfer is Accounted as Sale [Line Items]
Ownership interest percentage	100.00%	100.00%
Amount of ownership interest in loan securitization	$ 50	$ 50
Residual Certificates
Securitization or Asset-backed Financing Arrangement, Financial Asset for which Transfer is Accounted as Sale [Line Items]
Ownership interest percentage	100.00%	100.00%
Class A Notes
Securitization or Asset-backed Financing Arrangement, Financial Asset for which Transfer is Accounted as Sale [Line Items]
Amount of loan securitization sold to third parties	$ 607	$ 501
Proceeds from loan securitization sold to third parties	$ 607	$ 501
Private Education Loans Issuance 2016-A
Securitization or Asset-backed Financing Arrangement, Financial Asset for which Transfer is Accounted as Sale [Line Items]
Loans pledged as collateral			$ 571
Private Education Loans Issuance 2016-B
Securitization or Asset-backed Financing Arrangement, Financial Asset for which Transfer is Accounted as Sale [Line Items]
Loans pledged as collateral			$ 692

Derivative Financial Instrume54

Derivative Financial Instruments - Additional Information (Detail) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Derivative [Line Items]
Net derivatives	$ 47,600	$ 50,100
Cash collateral held	12,101	1,070
Cash collateral pledged	47,300	$ 54,800
Chicago Mercantile Exchange and the London Clearing House
Derivative [Line Items]
Notional value	$ 5,600,000

Derivative Financial Instrume55

Derivative Financial Instruments - Impact of Derivatives on Consolidated Balance Sheet (Detail) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Derivatives, Fair Value [Line Items]
Derivative Assets	$ 43,410	$ 15,314
Interest rate swaps
Derivatives, Fair Value [Line Items]
Derivative Assets	43,410	15,314
Derivative Liabilities	(52,578)	(30,497)
Total net derivatives	(9,168)	(15,183)
Interest rate swaps | Trading
Derivatives, Fair Value [Line Items]
Derivative Assets	414	83
Derivative Liabilities	(194)	(646)
Total net derivatives	220	(563)
Interest rate swaps | Cash Flow | Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative Assets	0	0
Derivative Liabilities	(52,197)	(27,512)
Total net derivatives	(52,197)	(27,512)
Interest rate swaps | Fair Value | Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative Assets	42,996	15,231
Derivative Liabilities	(187)	(2,339)
Total net derivatives	$ 42,809	$ 12,892

Derivative Financial Instrume56

Derivative Financial Instruments - Offsetting Assets and Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Other Assets
Gross position	$ 43,410	$ 15,314
Impact of master netting agreement	(14,111)	(9,278)
Derivative values with impact of master netting agreements (as carried on balance sheet)	29,299	6,036
Cash collateral (held) pledged	(12,101)	(1,070)
Net position	17,198	4,966
Other Liabilities
Cash collateral (held) pledged	47,300	54,800
Other Liabilities
Other Liabilities
Gross position	(52,578)	(30,497)
Impact of master netting agreement	14,111	9,278
Derivative values with impact of master netting agreements (as carried on balance sheet)	(38,467)	(21,219)
Cash collateral (held) pledged	47,283	54,845
Net position	$ 8,816	$ 33,626

Derivative Financial Instrume57

Derivative Financial Instruments - Notional Values (Details) - Interest rate swaps - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Derivatives, Fair Value [Line Items]
Notional values	$ 6,113,448	$ 5,495,857
Trading
Derivatives, Fair Value [Line Items]
Notional values	1,267,694	1,305,757
Cash Flow Hedges | Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional values	1,078,709	1,109,933
Fair Value Hedges | Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional values	$ 3,767,045	$ 3,080,167

Derivative Financial Instrume58

Derivative Financial Instruments - Impact of Derivatives on Consolidated Statements of Income (Details) - Interest rate swaps - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Trading
Gain (loss) on derivatives, net	$ 3,931	$ 1,573	$ 11,161	$ 10,702
Designated as Hedging Instrument | Fair Value Hedges
Fair Value Hedges
Hedge ineffectiveness gains (losses) recorded in earnings	3,199	(1,843)	2,000	(929)
Realized gains recorded in interest expense	6,944	7,531	21,593	22,512
Trading
Gain (loss) on derivatives, net	10,143	5,688	23,593	21,583
Designated as Hedging Instrument | Cash Flow Hedges
Cash Flow Hedges
Hedge ineffectiveness losses recorded in earnings	(843)	(273)	(1,524)	(542)
Realized losses recorded in interest expense	(4,381)	(5,411)	(13,588)	(16,157)
Trading
Gain (loss) on derivatives, net	(5,224)	(5,684)	(15,112)	(16,699)
Trading
Trading
Interest reclassification	537	853	1,897	2,846
Change in fair value of future interest payments recorded in earnings	(1,525)	716	783	2,972
Gain (loss) on derivatives, net	$ (988)	$ 1,569	$ 2,680	$ 5,818

Derivative Financial Instrume59

Derivative Financial Instruments - Impact of Derivatives on Consolidated Statement of Changes in Stockholders' Equity (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Amount of gain (loss) recognized in other comprehensive income (loss)	$ 4,943	$ (27,162)	$ (37,370)	$ (35,441)
Less: amount of (loss) gain reclassified in interest expense	(4,381)	5,411	(13,588)	16,157
Total change in other comprehensive income (loss) for unrealized gains (losses) on derivatives, before income tax benefit	$ 9,324	$ (21,751)	$ (23,782)	$ (19,284)

Stockholders' Equity - Common s

Stockholders' Equity - Common stock repurchased (Details) - $ / shares	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Equity [Abstract]
Shares repurchased related to employee stock-based compensation plans (in shares)	371,165	136,173	1,763,092	2,900,266
Average purchase price per share (in dollars per share)	$ 7.22	$ 8.88	$ 6.35	$ 9.76
Common shares issued (in shares)	561,100	361,779	3,727,574	5,569,853

Stockholders' Equity - Additio

Stockholders' Equity - Additional Detail (Details)	Sep. 30, 2016$ / shares
Common Stock
Class of Stock [Line Items]
Common stock closing price (usd per share)	$ 7.47

Earnings per Common Share (Deta

Earnings per Common Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Numerator:
Net income	$ 56,965	$ 45,724	$ 180,085	$ 184,439
Preferred stock dividends	5,316	4,913	15,698	14,606
Net income attributable to SLM Corporation common stock	$ 51,649	$ 40,811	$ 164,387	$ 169,833
Denominator:
Weighted average shares used to compute basic EPS (in shares)	428,077	426,019	427,711	425,384
Effect of dilutive securities:
Dilutive effect of stock options, restricted stock and restricted stock units and Employee Stock Purchase Plan (ESPP) (in shares)	5,446	6,528	4,368	7,147
Weighted average shares used to compute diluted EPS (in shares)	433,523	432,547	432,079	432,531
Basic earnings per common share attributable to SLM Corporation (in dollars per share)	$ 0.12	$ 0.10	$ 0.38	$ 0.40
Diluted earnings per common share attributable to SLM Corporation (in dollars per share)	$ 0.12	$ 0.09	$ 0.38	$ 0.39
Securities excluded from computation of EPS (in shares)	1,000	2,000	1,000	2,000

Fair Value Measurements - Valua

Fair Value Measurements - Valuation of Financial Instruments that are Marked-to-Market on Recurring Basis (Detail) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Assets
Mortgage-backed securities	$ 213,176	$ 195,391
Derivative instruments	29,299	6,036
Fair Value Measurements Recurring
Assets
Mortgage-backed securities	213,176	195,391
Derivative instruments	43,410	15,314
Total earning assets	256,586	210,705
Liabilities
Derivative instruments	(52,578)	(30,497)
Fair Value Measurements Recurring | Level 1
Assets
Mortgage-backed securities	0	0
Derivative instruments	0	0
Total earning assets	0	0
Liabilities
Derivative instruments	0	0
Fair Value Measurements Recurring | Level 2
Assets
Mortgage-backed securities	213,176	195,391
Derivative instruments	43,410	15,314
Total earning assets	256,586	210,705
Liabilities
Derivative instruments	(52,578)	(30,497)
Fair Value Measurements Recurring | Level 3
Assets
Mortgage-backed securities	0	0
Derivative instruments	0	0
Total earning assets	0	0
Liabilities
Derivative instruments	$ 0	$ 0

Fair Value Measurements - Fair

Fair Value Measurements - Fair Values of Financial Assets and Liabilities, Including Derivative Financial Instruments (Detail) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Earning assets
Loans held for investment, net, difference	$ 1,369,562	$ 713,135
Tax indemnification receivable	276,543	186,076
Derivative instruments	29,299	6,036
Total earning assets, difference	1,369,562	713,135
Interest-bearing liabilities
Long-term borrowings, difference	(31,296)	11,633
Total interest-bearing liabilities, difference	(56,209)	14,636
Excess of net asset fair value over carrying value	1,313,353	727,771
Certificates of deposit
Interest-bearing liabilities
Certificates of deposit, difference	(24,913)	3,003
Fair Value
Earning assets
Loans held for investment, net	16,130,066	12,343,726
Cash and cash equivalents	1,454,938	2,416,219
Available-for-sale investments	213,176	195,391
Accrued interest receivable	805,647	564,496
Tax indemnification receivable	276,543	186,076
Derivative instruments	43,410	15,314
Total earning assets	18,923,780	15,721,222
Interest-bearing liabilities
Short-term borrowings	350,000	500,175
Long-term borrowings	1,608,985	567,468
Accrued interest payable	26,587	16,385
Derivative instruments	52,578	30,497
Total interest-bearing liabilities	15,004,083	12,599,229
Fair Value | Money-market and savings accounts
Interest-bearing liabilities
Deposits	6,520,085	5,556,254
Fair Value | Certificates of deposit
Interest-bearing liabilities
Deposits	6,445,848	5,928,450
Carrying Value
Earning assets
Loans held for investment, net	14,760,504	11,630,591
Cash and cash equivalents	1,454,938	2,416,219
Available-for-sale investments	213,176	195,391
Accrued interest receivable	805,647	564,496
Tax indemnification receivable	276,543	186,076
Derivative instruments	43,410	15,314
Total earning assets	17,554,218	15,008,087
Interest-bearing liabilities
Short-term borrowings	350,000	500,175
Long-term borrowings	1,577,689	579,101
Accrued interest payable	26,587	16,385
Derivative instruments	52,578	30,497
Total interest-bearing liabilities	14,947,874	12,613,865
Carrying Value | Money-market and savings accounts
Interest-bearing liabilities
Deposits	6,520,085	5,556,254
Carrying Value | Certificates of deposit
Interest-bearing liabilities
Deposits	$ 6,420,935	$ 5,931,453

Arrangements with Navient Cor65

Arrangements with Navient Corporation (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Related Party Transaction [Line Items]
Minimum days past due that company may required spin-off company to purchase loans			90 days
Period of hardship forbearance			6 months
Split loans, net	$ 13,725,959,000		$ 13,725,959,000		$ 10,515,505,000
Interest income from related party	60,000	$ 200,000	300,000	$ 400,000
Gains on loans to related party	0	0	0	0
Write-down to fair value for loans sold to related party	1,400,000	1,900,000	5,000,000	5,600,000
Split Loans
Related Party Transaction [Line Items]
Split loans, net	71,000,000		71,000,000
Participated loans
Related Party Transaction [Line Items]
Loans sold to related party	$ 3,600,000	$ 6,600,000	$ 13,100,000	$ 21,100,000

Regulatory Capital - Well Capit

Regulatory Capital - Well Capitalized Regulatory Requirements (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Actual
Common Equity Tier I Capital (to Risk-Weighted Assets)	$ 1,928,979	$ 1,734,315
Tier 1 Capital (to Risk-Weighted Assets)	1,928,979	1,734,315
Total Capital (to Risk-Weighted Assets)	2,095,397	1,848,528
Tier 1 Capital (to Average Assets)	$ 1,928,979	$ 1,734,315
Actual Ratio
Common Equity Tier I Capital (to Risk-Weighted Assets)	12.40%	14.40%
Tier 1 Capital (to Risk-Weighted Assets)	12.40%	14.40%
Total Capital (to Risk-Weighted Assets)	13.40%	15.40%
Tier 1 Capital (to Average Assets)	11.60%	12.30%
Well Capitalized Regulatory Requirements, Amount
Common Equity Tier I Capital (to Risk-Weighted Assets)	$ 1,012,748	$ 781,638
Tier 1 Capital (to Risk-Weighted Assets)	1,246,459	962,017
Total Capital (to Risk-Weighted Assets)	1,558,074	1,202,521
Tier 1 Capital (to Average Assets)	$ 828,962	$ 704,979
Well Capitalized Regulatory Requirements, Ratio
Common Equity Tier I Capital (to Risk-Weighted Assets)	6.50%	6.50%
Tier 1 Capital (to Risk-Weighted Assets)	8.00%	8.00%
Total Capital (to Risk-Weighted Assets)	10.00%	10.00%
Tier 1 Capital (to Average Assets)	5.00%	5.00%

Regulatory Capital - Additional

Regulatory Capital - Additional Information (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Banking and Thrift [Abstract]
Dividends	$ 0	$ 0	$ 0	$ 0

Commitments, Contingencies an68

Commitments, Contingencies and Guarantees - Additional Information (Detail)	9 Months Ended
	Sep. 30, 2016USD ($)attorney_general	May 13, 2014USD ($)
Loss Contingencies [Line Items]
Contractual obligation	$ 1,800,000,000
Other liabilities reserve	$ 1,600,000
Loss contingency, loss emergence period	1 year
FDIC civil monetary penalties		$ 3,300,000
Number of Attorney Generals | attorney_general	2
Maximum
Loss Contingencies [Line Items]
Contingency refund (up to)		$ 30,000,000

Subsequent Event (Details)

Subsequent Event (Details) - Private Education Loans - USD ($) $ in Millions	Oct. 12, 2016	Jul. 21, 2016	May 26, 2016
Subsequent Event [Line Items]
Total loan amount securitized at inception for the 2016 on-balance sheet term securitization		$ 657	$ 551
Proceeds from loan securitization sold to third parties		$ 607	$ 501
Subsequent Event
Subsequent Event [Line Items]
Total loan amount securitized at inception for the 2016 on-balance sheet term securitization	$ 674
Amount of loan securitization sold to third parties	$ 674
Ownership interest percentage	100.00%
Proceeds from loan securitization sold to third parties	$ 673