Nelnet (NNI) 10-Q 6 Nov 14 2014 Q3 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information Document (USD $)	9 Months Ended
	Sep. 30, 2014	Jun. 28, 2013	Oct. 31, 2014	Oct. 31, 2014
			Common Class A [Member]	Common Class B [Member]
Document Information [Line Items]	'	'	'	'
Entity Registrant Name	'NELNET INC	'	'	'
Document Type	'10-Q	'	'	'
Current Fiscal Year End Date	'--12-31	'	'	'
Entity Common Stock, Shares Outstanding	'	'	34,772,102	11,486,932
Entity Public Float	'	$940,529,760.75	'	'
Amendment Flag	'false	'	'	'
Entity Central Index Key	'0001258602	'	'	'
Entity Current Reporting Status	'Yes	'	'	'
Entity Voluntary Filers	'No	'	'	'
Entity Filer Category	'Large Accelerated Filer	'	'	'
Entity Well-known Seasoned Issuer	'No	'	'	'
Document Period End Date	30-Sep-14	'	'	'
Document Fiscal Year Focus	'2014	'	'	'
Document Fiscal Period Focus	'Q3	'	'	'

Consolidated_Balance_Sheets_un

Consolidated Balance Sheets (unaudited) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Assets:	'	'
Student loans receivable (net of allowance for loan losses)	$28,701,344	$25,907,589
Cash and cash equivalents:	'	'
Cash and cash equivalents - not held at a related party	32,610	8,537
Cash and cash equivalents - held at a related party	41,969	54,730
Total cash and cash equivalents	74,579	63,267
Investments	147,780	192,040
Restricted cash and investments	867,507	735,123
Restricted cash - due to customers	72,836	167,576
Accrued interest receivable	352,205	314,553
Accounts receivable (net of allowance for doubtful accounts)	59,510	56,072
Goodwill	126,200	117,118
Intangible assets, net	42,876	6,132
Property and equipment, net	44,647	33,829
Other assets	141,156	115,043
Fair value of derivative instruments	68,009	62,507
Total assets	30,698,649	27,770,849
Liabilities:	'	'
Bonds and notes payable	28,737,456	25,955,289
Accrued interest payable	25,221	21,725
Other liabilities	190,765	164,300
Due to customers	72,836	167,576
Fair value of derivative instruments	14,814	17,969
Total liabilities	29,041,092	26,326,859
Nelnet, Inc. shareholders' equity:	'	'
Preferred stock	0	0
Additional paid-in capital	18,150	24,887
Retained earnings	1,633,577	1,413,492
Accumulated other comprehensive earnings	5,099	4,819
Total Nelnet, Inc. shareholders' equity	1,657,289	1,443,662
Noncontrolling interest	268	328
Total equity	1,657,557	1,443,990
Total liabilities and equity	30,698,649	27,770,849
Common Class A [Member]	'	'
Nelnet, Inc. shareholders' equity:	'	'
Common stock	348	349
Total equity	348	349
Common Class B [Member]	'	'
Nelnet, Inc. shareholders' equity:	'	'
Common stock	115	115
Total equity	115	115
Variable Interest Entity, Primary Beneficiary [Member]	'	'
Assets:	'	'
Student loans receivable (net of allowance for loan losses)	28,831,931	26,020,629
Cash and cash equivalents:	'	'
Restricted cash and investments	863,960	732,771
Other assets	351,516	313,748
Fair value of derivative instruments	-3,427	36,834
Liabilities:	'	'
Bonds and notes payable	29,084,859	26,244,222
Other liabilities	340,630	303,142
Equity:	'	'
Net assets of consolidated variable interest entities	$618,491	$556,618

Consolidated_Balance_Sheets_un1

Consolidated Balance Sheets (unaudited) (Parentheticals) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Thousands, except Share data, unless otherwise specified
Allowance for loan losses	$51,968	$55,122
Allowance for doubtful accounts	$1,842	$3,845
Preferred stock, par value (in dollars per share)	$0.01	$0.01
Preferred stock, authorized shares	50,000,000	50,000,000
Preferred stock, issued shares	0	0
Preferred stock, outstanding shares	0	0
Common Class A [Member]	'	'
Par Value (in dollars per share)	$0.01	$0.01
Shares Authorized	600,000,000	600,000,000
Shares Issued	34,796,723	34,881,338
Shares Outstanding	34,796,723	34,881,338
Common Class B [Member]	'	'
Par Value (in dollars per share)	$0.01	$0.01
Shares Authorized	60,000,000	60,000,000
Shares Issued	11,486,932	11,495,377
Shares Outstanding	11,486,932	11,495,377

Consolidated_Statements_of_Inc

Consolidated Statements of Income (unaudited) (USD $)	3 Months Ended		9 Months Ended
In Thousands, except Share data, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Interest income:	'	'	'	'
Loan interest	$187,862	$158,675	$520,224	$472,277
Investment interest	1,562	1,562	5,023	4,662
Total interest income	189,424	160,237	525,247	476,939
Interest expense:	'	'	'	'
Interest on bonds and notes payable	71,937	55,315	201,176	171,800
Net interest income	117,487	104,922	324,071	305,139
Less provision for loan losses	2,000	5,000	6,000	15,000
Net interest income after provision for loan losses	115,487	99,922	318,071	290,139
Other income (expense):	'	'	'	'
Loan and guaranty servicing revenue	52,659	64,582	183,876	180,261
Tuition payment processing and campus commerce revenue	26,399	19,927	73,468	61,694
Enrollment services revenue	22,936	22,563	65,092	76,343
Other income	7,650	8,613	41,096	30,317
Gain on sale of loans and debt repurchases	0	2,138	57	10,900
Derivative market value and foreign currency adjustments and derivative settlements, net	24,203	-16,648	21,508	24,612
Total other income (expense)	133,847	101,175	385,097	384,127
Operating expenses:	'	'	'	'
Salaries and benefits	61,098	48,712	167,470	144,049
Cost of Services	14,178	14,668	41,964	51,097
Depreciation and amortization	5,493	4,340	15,490	13,037
Other	36,676	39,887	112,680	109,193
Total operating expenses	117,445	107,607	337,604	317,376
Income before income taxes	131,889	93,490	365,564	356,890
Income tax expense	-46,513	-30,444	-130,202	-123,637
Net income	85,376	63,046	235,362	233,253
Net income attributable to noncontrolling interest	157	216	1,363	1,101
Net income attributable to Nelnet, Inc.	$85,219	$62,830	$233,999	$232,152
Earnings per common share:	'	'	'	'
Net income attributable to Nelnet, Inc. shareholders - basic and diluted	$1.84	$1.35	$5.03	$4.98
Weighted average common shares outstanding - basic and diluted	46,432,680	46,496,612	46,496,309	46,593,241

Consolidated_Statements_of_Com

Consolidated Statements of Comprehensive Income (unaudited) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Net income	$85,376	$63,046	$235,362	$233,253
Available-for-sale securities:	'	'	'	'
Unrealized holding gains (losses) arising during period, net	-738	5,689	8,763	6,875
Less reclassification adjustment for gains recognized in net income, net	-8	-730	-8,319	-2,246
Income tax effect	276	-1,834	-164	-1,720
Total other comprehensive income (loss)	-470	3,125	280	2,909
Comprehensive income	84,906	66,171	235,642	236,162
Comprehensive income attributable to noncontrolling interest	157	216	1,363	1,101
Comprehensive income attributable to Nelnet, Inc.	$84,749	$65,955	$234,279	$235,061

Consolidated_Statements_of_Sha

Consolidated Statements of Shareholders' Equity (unaudited) (USD $)	Total	Preferred Stock [Member]	Common Class A [Member]	Common Class B [Member]	Additional paid-in capital [Member]	Retained earnings [Member]	Accumulated other comprehensive earnings [Member]	Noncontrolling interest [Member]
In Thousands, except Share data, unless otherwise specified
Balance at Jun. 30, 2013	$1,319,595	$0	$350	$115	$27,004	$1,289,416	$2,597	$113
Balance (in Shares) at Jun. 30, 2013	'	0	34,988,110	11,495,377	'	'	'	'
Increase (Decrease) in Stockholders' Equity [Roll Forward]	'	'	'	'	'	'	'	'
Net income attributable to Nelnet, Inc.	62,830	'	'	'	'	62,830	'	'
Net income attributable to noncontrolling interest	216	'	'	'	'	'	'	216
Net income	63,046	'	'	'	'	'	'	'
Other comprehensive income (loss)	3,125	'	'	'	'	'	3,125	'
Distribution to noncontrolling interest	-279	'	'	'	'	'	'	-279
Cash dividend on Class A and Class B common stock	-4,637	'	'	'	'	-4,637	'	'
Issuance of common stock, net of forfeitures	264	'	0	0	264	'	'	'
Issuance of common stock, net of forfeitures (in Shares)	'	'	-745	0	'	'	'	'
Compensation expense for stock based awards	824	'	'	'	824	'	'	'
Repurchase of common stock	-4,025	'	-1	0	-4,024	'	'	'
Repurchase of common stock (in Shares)	'	'	-111,220	0	'	'	'	'
Balance at Sep. 30, 2013	1,377,913	0	349	115	24,068	1,347,609	5,722	50
Balance (in Shares) at Sep. 30, 2013	'	0	34,876,145	11,495,377	'	'	'	'
Balance at Dec. 31, 2012	1,165,213	0	351	115	32,540	1,129,389	2,813	5
Balance (in Shares) at Dec. 31, 2012	'	0	35,116,913	11,495,377	'	'	'	'
Increase (Decrease) in Stockholders' Equity [Roll Forward]	'	'	'	'	'	'	'	'
Net income attributable to Nelnet, Inc.	232,152	'	'	'	'	232,152	'	'
Net income attributable to noncontrolling interest	1,101	'	'	'	'	'	'	1,101
Noncontrolling Interest, Increase from Sale of Parent Equity Interest	5	'	'	'	'	'	'	5
Net income	233,253	'	'	'	'	'	'	'
Other comprehensive income (loss)	2,909	'	'	'	'	'	2,909	'
Distribution to noncontrolling interest	-1,061	'	'	'	'	'	'	-1,061
Cash dividend on Class A and Class B common stock	-13,932	'	'	'	'	-13,932	'	'
Issuance of common stock, net of forfeitures	2,233	'	2	0	2,231	'	'	'
Issuance of common stock, net of forfeitures (in Shares)	'	'	149,608	0	'	'	'	'
Compensation expense for stock based awards	2,308	'	'	'	2,308	'	'	'
Repurchase of common stock	-13,015	'	-4	0	-13,011	'	'	'
Repurchase of common stock (in Shares)	'	'	-390,376	0	'	'	'	'
Balance at Sep. 30, 2013	1,377,913	0	349	115	24,068	1,347,609	5,722	50
Balance (in Shares) at Sep. 30, 2013	'	0	34,876,145	11,495,377	'	'	'	'
Balance at Dec. 31, 2013	1,443,990	0	349	115	24,887	1,413,492	4,819	328
Balance (in Shares) at Dec. 31, 2013	'	0	34,881,338	11,495,377	'	'	'	'
Increase (Decrease) in Stockholders' Equity [Roll Forward]	'	'	'	'	'	'	'	'
Net income attributable to Nelnet, Inc.	233,999	'	'	'	'	233,999	'	'
Net income attributable to noncontrolling interest	1,363	'	'	'	'	'	'	1,363
Noncontrolling Interest, Increase from Sale of Parent Equity Interest	201	'	'	'	'	'	'	201
Net income	235,362	'	'	'	'	'	'	'
Other comprehensive income (loss)	280	'	'	'	'	'	280	'
Distribution to noncontrolling interest	-1,624	'	'	'	'	'	'	-1,624
Cash dividend on Class A and Class B common stock	-13,914	'	'	'	'	-13,914	'	'
Issuance of common stock, net of forfeitures	3,341	'	2	0	3,339	'	'	'
Issuance of common stock, net of forfeitures (in Shares)	'	'	234,236	0	'	'	'	'
Compensation expense for stock based awards	3,258	'	'	'	3,258	'	'	'
Repurchase of common stock	-13,337	'	-3	0	-13,334	'	'	'
Conversion of Common Stock, Shares Converted	'	'	8,445	-8,445	'	'	'	'
Conversion of Common Stock, Amount Converted	0	'	0	0	'	'	'	'
Repurchase of common stock (in Shares)	'	'	-327,296	0	'	'	'	'
Balance at Sep. 30, 2014	1,657,557	0	348	115	18,150	1,633,577	5,099	268
Balance (in Shares) at Sep. 30, 2014	'	0	34,796,723	11,486,932	'	'	'	'
Balance at Jun. 30, 2014	1,580,128	0	349	115	20,721	1,552,988	5,569	386
Balance (in Shares) at Jun. 30, 2014	'	0	34,859,786	11,491,932	'	'	'	'
Increase (Decrease) in Stockholders' Equity [Roll Forward]	'	'	'	'	'	'	'	'
Net income attributable to Nelnet, Inc.	85,219	'	'	'	'	85,219	'	'
Net income attributable to noncontrolling interest	157	'	'	'	'	'	'	157
Net income	85,376	'	'	'	'	'	'	'
Other comprehensive income (loss)	-470	'	'	'	'	'	-470	'
Distribution to noncontrolling interest	-275	'	'	'	'	'	'	-275
Cash dividend on Class A and Class B common stock	-4,630	'	'	'	'	-4,630	'	'
Issuance of common stock, net of forfeitures	213	'	0	0	213	'	'	'
Issuance of common stock, net of forfeitures (in Shares)	'	'	28,729	0	'	'	'	'
Compensation expense for stock based awards	1,248	'	'	'	1,248	'	'	'
Repurchase of common stock	-4,033	'	-1	0	-4,032	'	'	'
Conversion of Common Stock, Shares Converted	'	'	5,000	-5,000	'	'	'	'
Conversion of Common Stock, Amount Converted	0	'	0	0	'	'	'	'
Repurchase of common stock (in Shares)	'	'	-96,792	0	'	'	'	'
Balance at Sep. 30, 2014	$1,657,557	$0	$348	$115	$18,150	$1,633,577	$5,099	$268
Balance (in Shares) at Sep. 30, 2014	'	0	34,796,723	11,486,932	'	'	'	'

Consolidated_Statements_of_Sha1

Consolidated Statements of Shareholders' Equity (unaudited) (Parentheticals) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Common Class A [Member]	'	'	'	'
Dividends paid per common share	$0.10	$0.10	$0.30	$0.30
Common Class B [Member]	'	'	'	'
Dividends paid per common share	$0.10	$0.10	$0.30	$0.30

Consolidated_Statements_of_Cas

Consolidated Statements of Cash Flows (unaudited) (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013
Net income attributable to Nelnet, Inc.	$233,999	$232,152
Net income attributable to noncontrolling interest	1,363	1,101
Net income	235,362	233,253
Adjustments to reconcile net income to net cash provided by operating activities:	'	'
Depreciation and amortization, including debt discounts and student loan premiums and deferred origination costs	78,318	58,330
Student loan discount accretion	-32,393	-26,333
Provision for loan losses	6,000	15,000
Derivative market value adjustment	431	-73,743
Foreign currency transaction adjustment	-39,216	25,902
Payment for interest rate swap option	-9,087	0
Payments to terminate and/or amend derivative instruments, net of proceeds	0	-6,469
Gain on sale of loans	0	-34
Gain from debt repurchases	-57	-10,866
Gain from sales of available-for-sale securities, net	-8,319	-2,246
Purchases of student loans - held for sale	0	-28,480
Purchases of trading securities, net	-3,380	0
Deferred income tax expense (benefit)	21,391	13,279
Non-cash compensation expense	3,364	2,513
Other	5,638	44
Decrease in accrued interest receivable	4,303	4,168
(Increase) decrease in accounts receivable	-1,884	687
Decrease (increase) in other assets	2,723	-2,445
Increase (decrease) in accrued interest payable	2,314	-552
(Decrease) increase in other liabilities	-2,441	598
Net cash provided by operating activities	263,067	202,606
Cash flows from investing activities, net of acquisitions:	'	'
Purchases of student loans and student loan residual interests	-3,211,153	-1,696,253
Purchases Of Student Loans From Related Party	-175	-466,941
Net proceeds from student loan repayments, claims, capitalized interest, participations, and other	2,721,886	2,269,253
Proceeds from sale of student loans	8	11,287
Purchases of available-for-sale securities	-143,695	-196,657
Proceeds from sales of available-for-sale securities	200,098	52,733
Purchases of other investments, net	-35,454	-8,316
Repayments of notes and other receivables	11,006	0
Purchases of property and equipment, net	-21,691	-11,720
(Increase) Decrease in restricted cash and investments	-32,720	140,536
Business acquisition, net of cash acquired	-45,583	0
Net cash (used in) provided by investing activities	-557,473	93,922
Cash flows from financing activities, net of borrowings assumed:	'	'
Payments on bonds and notes payable	-3,013,378	-4,159,079
Proceeds from issuance of bonds and notes payable	3,362,227	3,888,772
Payments of debt issuance costs	-14,933	-13,295
Dividends paid	-13,914	-13,932
Repurchases of common stock	-13,337	-13,015
Proceeds from issuance of common stock	476	437
Issuance of noncontrolling interest	201	5
Distribution to noncontrolling interest	-1,624	-1,061
Net cash provided by (used in) financing activities	305,718	-311,168
Net increase (decrease) in cash and cash equivalents	11,312	-14,640
Cash and cash equivalents, beginning of period	63,267	66,031
Cash and cash equivalents, end of period	74,579	51,391
Supplemental disclosures of cash flow information:	'	'
Interest paid	155,962	148,482
Income taxes paid, net of refunds	118,866	114,744
Noncash activity:	'	'
Investing activity - student loans and other assets acquired	2,571,997	0
Financing activity - borrowings and other liabilities assumed in acquisition of student loans	$2,444,874	$0

Basis_of_Financial_Reporting

Basis of Financial Reporting	9 Months Ended
	Sep. 30, 2014
Organization, Consolidation and Presentation of Financial Statements [Abstract]	'
Basis of Financial Reporting	'
	Basis of Financial Reporting
	The accompanying unaudited consolidated financial statements of Nelnet, Inc. and subsidiaries (the “Company”) as of September 30, 2014 and for the three and nine months ended September 30, 2014 and 2013 have been prepared on the same basis as the audited consolidated financial statements for the year ended December 31, 2013 and, in the opinion of the Company’s management, the unaudited consolidated financial statements reflect all adjustments, consisting of normal recurring adjustments, necessary for a fair presentation of results of operations for the interim periods presented. The preparation of financial statements in conformity with U.S. generally accepted accounting principles 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, 2014 are not necessarily indicative of the results for the year ending December 31, 2014. The unaudited consolidated financial statements should be read in conjunction with the Company’s Annual Report on Form 10-K for the year ended December 31, 2013 (the "2013 Annual Report").

Student_Loans_Receivable_and_A

Student Loans Receivable and Allowance for Loan Losses	9 Months Ended
	Sep. 30, 2014
Receivables [Abstract]	'
Financing Receivables [Text Block]	'
	Student Loans Receivable and Allowance for Loan Losses
	Student loans receivable consisted of the following:
		As of			As of
		September 30, 2014			December 31, 2013
	Federally insured loans
	Stafford and other	$	6,218,910		6,686,626
	Consolidation	22,632,689			19,363,577
	Total	28,851,599			26,050,203
	Non-federally insured loans	77,623			71,103
		28,929,222			26,121,306
	Loan discount, net of unamortized loan premiums and deferred origination costs (a)	(175,910		)	(158,595	)
	Allowance for loan losses – federally insured loans	(39,470		)	(43,440	)
	Allowance for loan losses – non-federally insured loans	(12,498		)	(11,682	)
		$	28,701,344		25,907,589
	(a)	For loans purchased where there is evidence of credit deterioration since the origination of the loan, the Company records a credit discount, separate from the allowance for loan losses, which is non-accretable to interest income. Remaining discounts and premiums for purchased loans are recognized in interest income over the remaining estimated lives of the loans. The Company continues to evaluate credit losses associated with purchased loans based on current information and changes in expectations to determine the need for any additional allowance for loan losses. As of September 30, 2014 and December 31, 2013, "loan discount, net of unamortized loan premiums and deferred origination costs" included $28.8 million and $20.2 million, respectively, of non-accretable discount associated with purchased loans of $8.4 billion and $4.4 billion, respectively.
	Student Loan Residual Interests
	On April 25, 2014, the Company acquired the ownership interest in three Federal Family Education Loan Program ("FFEL Program" or "FFELP") student loan securitization trusts giving the Company rights to the residual interest in a total of $2.6 billion of securitized federally insured loans and related assets. The three trusts include loans funded to term with $2.6 billion (par value) of notes payable that carry interest rates on a spread to LIBOR or are set and periodically reset via a "dutch auction".
	The Company has consolidated these trusts on its consolidated balance sheet because management has determined the Company is the primary beneficiary of the trusts. Upon acquisition, the Company recorded all assets and liabilities of the trusts at fair value, resulting in the recognition of a student loan discount of $68.7 million and a notes payable discount of $163.7 million. These discounts will be accreted using the effective interest method over the lives of the underlying assets and liabilities. All other assets acquired and liabilities assumed (restricted cash, accrued interest receivable/payable, and other assets/liabilities) were recorded at cost, which approximates fair value.
	Activity in the Allowance for Loan Losses
	The provision for loan losses represents the periodic expense of maintaining an allowance appropriate to absorb losses, net of recoveries, inherent in the portfolio of student loans. Activity in the allowance for loan losses is shown below.
		Three months ended September 30,					Nine months ended September 30,
		2014			2013		2014		2013
	Balance at beginning of period	$	52,467		51,611		55,122		51,902
	Provision for loan losses:
	Federally insured loans	2,000			5,000		7,000		16,000
	Non-federally insured loans	—			—		(1,000	)	(1,000	)
	Total provision for loan losses	2,000			5,000		6,000		15,000
	Charge-offs:
	Federally insured loans	(3,521		)	(3,142	)	(11,290	)	(12,472	)
	Non-federally insured loans	(623		)	(906	)	(1,642	)	(2,270	)
	Total charge-offs	(4,144		)	(4,048	)	(12,932	)	(14,742	)
	Recoveries - non-federally insured loans	279			363		989		1,173
	Purchase (sale) of federally insured loans, net	70			700		320		(1,243	)
	Transfer from repurchase obligation related to non-federally insured loans repurchased, net	1,296			571		2,469		2,107
	Balance at end of period	$	51,968		54,197		51,968		54,197
	Allocation of the allowance for loan losses:
	Federally insured loans	$	39,470		42,406		39,470		42,406
	Non-federally insured loans	12,498			11,791		12,498		11,791
	Total allowance for loan losses	$	51,968		54,197		51,968		54,197
	Repurchase Obligations
	As of September 30, 2014, the Company had participated a cumulative amount of $103.6 million (par value) of non-federally insured loans to third parties. Loans participated under these agreements have been accounted for by the Company as loan sales. Accordingly, the participation interests sold are not included in the Company’s consolidated balance sheets. Per the terms of the servicing agreements, the Company’s servicing operations are obligated to repurchase loans subject to the participation interests in the event such loans become 60 days or 90 days delinquent.
	In addition, in 2011, the Company sold a portfolio of non-federally insured loans for proceeds of $91.3 million (100% of par value).  The Company retained credit risk related to this portfolio and will pay cash to purchase back any loans which become 60 days delinquent. As of September 30, 2014, the balance of this portfolio was $57.0 million (par value).
	The Company’s estimate related to its obligation to repurchase these loans is included in “other liabilities” in the Company’s consolidated balance sheets. The activity related to this accrual is detailed below.
		Three months ended September 30,					Nine months ended September 30,
		2014			2013		2014		2013
	Beginning balance	$	14,827		14,594		16,143		16,130
	Loans repurchased	(1,296		)	(571	)	(2,612	)	(2,107	)
	Ending balance	$	13,531		14,023		13,531		14,023
	Student Loan Status and Delinquencies
	Delinquencies have the potential to adversely impact the Company’s earnings through increased servicing and collection costs and account charge-offs.  The percent of non-federally insured loans that were delinquent 31 days or greater as of September 30, 2014, December 31, 2013, and September 30, 2013 was 11.7 percent, 12.7 percent, and 13.4 percent, respectively. The table below shows the Company’s federally insured student loan delinquency amounts.
		As of September 30, 2014					As of December 31, 2013					As of September 30, 2013
	Federally insured loans:
	Loans in-school/grace/deferment	$	3,072,318				$	2,872,505				$	3,039,819
	Loans in forbearance	3,505,103					3,370,025					3,396,748
	Loans in repayment status:
	Loans current	18,672,178			83.8	%	16,337,922			82.5	%	15,236,060		83.1	%
	Loans delinquent 31-60 days	990,696			4.5		967,318			4.9		851,397		4.6
	Loans delinquent 61-90 days	569,879			2.6		550,333			2.8		480,285		2.6
	Loans delinquent 91-120 days	452,463			2		390,791			2		372,697		2
	Loans delinquent 121-270 days	1,183,616			5.3		1,117,936			5.6		978,234		5.3
	Loans delinquent 271 days or greater	405,346			1.8		443,373			2.2		437,337		2.4
	Total loans in repayment	22,274,178			100	%	19,807,673			100	%	18,356,010		100	%
	Total federally insured loans	$	28,851,599				$	26,050,203				$	24,792,577

Bonds_and_Notes_Payable

Bonds and Notes Payable	9 Months Ended
	Sep. 30, 2014
Debt Disclosure [Abstract]	'
Bonds and Notes Payable	'
	Bonds and Notes Payable
	The following tables summarize the Company’s outstanding debt obligations by type of instrument:
		As of September 30, 2014
		Carrying				Interest rate		Final maturity
		amount				range
	Variable-rate bonds and notes issued in asset-backed securitizations:
	Bonds and notes based on indices	$	26,639,879			0.24% - 6.90%		5/25/18 - 8/26/52
	Bonds and notes based on auction or remarketing	1,557,875				0.07% - 2.11%		5/1/28 - 11/26/46
	Total variable-rate bonds and notes	28,197,754
	FFELP warehouse facilities	787,042				0.16% - 0.25%		1/17/16 - 6/11/17
	Unsecured line of credit	—				—		6/30/19
	Unsecured debt - Junior Subordinated Hybrid Securities	96,457				3.61%		9/15/61
	Other borrowings	63,504				1.66% - 5.10%		11/14/14 - 12/31/18
		29,144,757
	Discount on bonds and notes payable	(407,301		)
	Total	$	28,737,456
		As of December 31, 2013
		Carrying				Interest rate		Final maturity
		amount				range
	Variable-rate bonds and notes issued in asset-backed securitizations:
	Bonds and notes based on indices	$	23,479,893			0.25% - 6.90%		5/25/18 - 8/26/52
	Bonds and notes based on auction or remarketing	1,134,250				0.07% - 2.17%		5/1/28 - 11/26/46
	Total variable-rate bonds and notes	24,614,143
	FFELP warehouse facilities	1,396,344				0.17% - 0.25%		1/17/16 - 6/12/16
	Unsecured line of credit	45,000				1.67%		3/28/18
	Unsecured debt - Junior Subordinated Hybrid Securities	96,457				3.62%		9/15/61
	Other borrowings	61,401				1.67% - 5.10%		4/11/14 - 11/11/15
		26,213,345
	Discount on bonds and notes payable	(258,056		)
	Total	$	25,955,289
	FFELP Warehouse Facilities
	The Company funds a portion of its FFELP loan acquisitions using its FFELP warehouse facilities. Student loan warehousing allows the Company to buy and manage student loans prior to transferring them into more permanent financing arrangements.
	As of September 30, 2014, the Company had three FFELP warehouse facilities as summarized below.
			NHELP-III				NHELP-II (a)		NFSLW-I (b)		Total
	Maximum financing amount		$	750,000			500,000		500,000		1,750,000
	Amount outstanding		438,265				40,433		308,344		787,042
	Amount available		$	311,735			459,567		191,656		962,958
	Expiration of liquidity provisions		February 5, 2015				December 17, 2014		June 11, 2015
	Final maturity date		January 17, 2016				December 17, 2016		June 11, 2017
	Maximum advance rates		92.2 - 95.0%				84.5 - 94.5%		92.0 - 98.0%
	Minimum advance rates		92.2 - 95.0%				84.5 - 94.5%		84.0 - 90.0%
	Advanced as equity support		$	26,264			4,195		14,778		45,237
	(a)	On September 30, 2014, the Company amended the agreement for this warehouse facility to change the expiration date for the liquidity provisions to December 17, 2014, and change the maturity date to December 17, 2016.
	(b)	On April 15, 2014, the Company amended the agreement for this warehouse facility to change the expiration date for the liquidity provisions to June 11, 2015, and change the maturity date to June 11, 2017.
	Asset-backed Securitizations
	The following table summarizes the asset-backed securitization transactions completed during the nine months ended September 30, 2014.
			2014-1				2014-2								2014-3		2014-4						2014-5		2014-6 (a)		Total
							Class A-1 notes		Class A-2 notes		Class A-3 notes		2014-2 total				Class A-1 notes		Class A-2 notes		2014-4 total
	Date securities issued		2/6/14				3/12/14		3/12/14		3/12/14		3/12/14		4/30/14		5/23/14		5/23/14		5/23/14		6/18/14		7/31/14
	Total original principal amount		$	458,500									509,000		719,800						384,500		603,000		565,000		$	3,239,800
	Class A senior notes:
	Total original principal amount		$	445,000			191,000		222,000		84,000		497,000		700,700		267,500		107,500		375,000		587,000		565,000		3,169,700
	Bond discount		—				—		—		(535	)	(535	)	—		—		—		—		—		(3,124	)	(3,659		)
	Issue price		$	445,000			191,000		222,000		83,465		496,465		700,700		267,500		107,500		375,000		587,000		561,876		3,166,041
	Cost of funds (1-month LIBOR plus:)		0.57		%		0.28	%	0.6	%	0.85	%			0.58	%	0.54	%	0.95	%			0.55	%	0.65	%
	Final maturity date		9/25/41				6/25/21		3/25/30		7/27/37				6/25/41		11/27/34		11/25/43				7/25/41		11/25/47
	Class B subordinated notes:
	Total original principal amount		$	13,500									12,000		19,100						9,500		16,000				70,100
	Bond discount		(1,132		)								(1,046	)	(1,467	)					(1,138	)	(1,232	)			(6,015		)
	Issue price		$	12,368									10,954		17,633						8,362		14,768				64,085
	Cost of funds (1-month LIBOR plus:)		1.5		%								1.5	%	1.5	%					1.5	%	1.5	%
	Final maturity date		10/25/47										6/25/41		10/25/50						9/25/51		5/25/49
	(a)	Total original principal amount excludes the Class B subordinated notes of $8.3 million that were retained at issuance. As of September 30, 2014, the Company has a total of $64.6 million (par value) of its own Class B subordinated notes remaining from prior completed asset-backed securitizations that are not included in the Company's consolidated balance sheet. If the Company sells these notes to third parties, the Company would obtain cash proceeds equal to the market value of the notes on the date of such sale.  Upon sale, these notes would be shown as “bonds and notes payable” in the Company's consolidated balance sheet.  The Company believes the market value of such notes is currently less than par value.  Any excess of the par value over the market value on the date of sale would be recognized by the Company as interest expense over the life of the bonds.
Unsecured Line of Credit
On June 30, 2014, the Company's unsecured line of credit was amended to increase the line of credit from $275.0 million to $350.0 million and extend the maturity date from March 28, 2018 to June 30, 2019. In addition, the amendment revised certain covenants related to maintenance of a minimum consolidated net worth, limitations on recourse indebtedness and liens, and a limitation on the amount of non-federally insured student loans in the Company’s portfolio. As of September 30, 2014, the $350.0 million unsecured line of credit had no amount outstanding and $350.0 million was available for future use.
Other Borrowings
On October 31, 2014, the Company amended its existing $50.0 million line of credit, which is collateralized by asset-backed security investments, to increase the borrowing capacity to $75.0 million and extend the maturity date to October 31, 2016. The renewed line of credit has covenants and cross default provisions similar to those under the Company's unsecured line of credit.
Debt Repurchases
The Company repurchased $2.5 million (par value) and $15.4 million (par value) of its own asset-backed debt securities during the three months ended September 30, 2014 and 2013, respectively, and recognized no gain on such purchases for the three months ended September 30, 2014, and gains of $2.1 million for the same period in 2013. During the nine months ended September 30, 2014 and 2013, the Company repurchased $4.0 million (par value) and $84.7 million (par value), respectively, of its own asset-backed debt securities and recognized gains on such purchases of approximately $57,000 and $10.9 million, respectively.

Derivative_Financial_Instrumen

Derivative Financial Instruments	9 Months Ended
	Sep. 30, 2014
Derivative Instruments and Hedging Activities Disclosure [Abstract]	'
Derivative Financial Instruments	'
	Derivative Financial Instruments
	The Company uses derivative financial instruments primarily to manage interest rate risk and foreign currency exchange risk. Derivative instruments used as part of the Company's risk management strategy are further described in note 6 of the notes to consolidated financial statements included in the 2013 Annual Report. A tabular presentation of such derivatives outstanding as of September 30, 2014 and December 31, 2013 is presented below.
	Basis Swaps
	The following table summarizes the Company’s basis swaps outstanding as of September 30, 2014 and December 31, 2013 in which the Company receives three-month LIBOR set discretely in advance and pays one-month LIBOR plus or minus a spread as defined in the agreements (the "1:3 Basis Swaps").
		Maturity			Notional amount
		2021			$	250,000
		2022			1,900,000
		2023			3,650,000
		2024			250,000
		2026			800,000
		2028			100,000
		2036			700,000
		2039	(a)		150,000
		2040	(b)		200,000
					$	8,000,000		(c)
	(a)This derivative has a forward effective start date in 2015.
	(b)This derivative has a forward effective start date in 2020.
	(c)	The weighted average rate paid by the Company on the 1:3 Basis Swaps as of September 30, 2014 and December 31, 2013 was one-month LIBOR plus 3.5 basis points.
	Interest Rate Swaps – Floor Income Hedges
	The following table summarizes the outstanding derivative instruments used by the Company to economically hedge loans earning fixed rate floor income.
			As of September 30, 2014							As of December 31, 2013
	Maturity		Notional amount				Weighted average fixed rate paid by the Company (a)			Notional amount				Weighted average fixed rate paid by the Company (a)
	2014		$	—			—	%		$	1,750,000			0.71	%
	2015		1,100,000				0.89			1,100,000				0.89
	2016		750,000				0.85			750,000				0.85
	2017		1,250,000				0.86			1,250,000				0.86
			$	3,100,000			0.87	%		$	4,850,000			0.81	%
	(a)	For all interest rate derivatives, the Company receives discrete three-month LIBOR.
	On August 20, 2014, the Company paid $9.1 million for an interest rate swap option to economically hedge loans earning fixed rate floor income. The interest rate swap option gives the Company the right, but not the obligation, to enter into a $250 million notional interest rate swap in which the Company would pay a fixed amount of 3.30% and receive discrete one-month LIBOR. If the interest rate swap option is exercised, the swap would become effective in 2019 and mature in 2024. The Company recorded this derivative instrument at fair value and will record the change in fair value of the instrument on the consolidated statement of income.
	Interest Rate Swaps – Unsecured Debt Hedges
	The Company had the following derivatives outstanding as of September 30, 2014 and December 31, 2013 that are used to effectively convert the variable interest rate on a portion of the Junior Subordinated Hybrid Securities ("Hybrid Securities") to a fixed rate.
	Maturity		Notional amount				Weighted average fixed rate paid by the Company (a)
	2036		$	25,000			4.28	%
	(a)	For all interest rate derivatives, the Company receives discrete three-month LIBOR.
	Foreign Currency Exchange Risk
	In 2006, the Company issued €352.7 million of student loan asset-backed Euro Notes (the "Euro Notes") with an interest rate based on a spread to the EURIBOR index. As a result of the Euro Notes, the Company is exposed to market risk related to fluctuations in foreign currency exchange rates between the U.S. dollar and Euro. The principal and accrued interest on these notes are re-measured at each reporting period and recorded in the Company’s consolidated balance sheet in U.S. dollars based on the foreign currency exchange rate on that date.
	The Company entered into a cross-currency interest rate swap in connection with the issuance of the Euro Notes. Under the terms of the cross-currency interest rate swap, the Company receives from the counterparty a spread to the EURIBOR index based on a notional amount of €352.7 million and pays a spread to the LIBOR index based on a notional amount of $450.0 million. In addition, under the terms of this agreement, all principal payments on the Euro Notes will effectively be paid at the exchange rate in effect between the U.S. dollar and Euro as of the issuance of the notes.
	The following table shows the income statement impact as a result of the re-measurement of the Euro Notes and the change in the fair value of the related derivative instrument.
		Three months ended September 30,							Nine months ended September 30,
		2014				2013 (b)			2014			2013 (b)
	Re-measurement of Euro Notes	$	37,418			(39,974	)		39,216			(25,902	)
	Change in fair value of cross-currency interest rate swaps	(37,224		)		39,074			(40,261	)		18,978
	Total impact to consolidated statements of income - income (expense) (a)	$	194			(900	)		(1,045	)		(6,924	)
	(a)	The financial statement impact of the above items is included in "Derivative market value and foreign currency adjustments and derivative settlements, net" in the Company's consolidated statements of income.
	(b)	The 2013 operating results include the re-measurement of an additional €420.5 million of student loan asset-backed Euro notes and the change in fair value of a related cross-currency interest rate swap entered into in connection with the issuance of such notes. In November 2013, the principal amount outstanding on the notes was changed to U.S. dollars and the cross-currency interest swap was terminated.
	The re-measurement of the Euro-denominated bonds generally correlates with the change in fair value of the corresponding cross-currency interest rate swap. However, the Company will experience unrealized gains or losses related to the cross-currency interest rate swap if the two underlying indices (and related forward curve) do not move in parallel.
	Consolidated Financial Statement Impact Related to Derivatives
	The following table summarizes the fair value of the Company’s derivatives as reflected in the consolidated balance sheets:
		Fair value of asset derivatives							Fair value of liability derivatives
		As of				As of			As of			As of
		September 30,				December 31,			September 30,			December 31,
		2014				2013			2014			2013
	1:3 basis swaps	$	50,965			18,490			—			—
	Interest rate swaps - floor income hedges	8,804				7,183			6,297			15,849
	Interest rate swap option - floor income hedge	8,240				—			—			—
	Interest rate swaps - hybrid debt hedges	—				—			5,090			2,120
	Cross-currency interest rate swap	—				36,834			3,427			—
	Total	$	68,009			62,507			14,814			17,969
	During the nine months ended September 30, 2013, the Company terminated certain derivatives for gross proceeds and payments of $2.7 million and $9.2 million, respectively. There were no derivative terminations during the first nine months of 2014.
	Offsetting of Derivative Assets/Liabilities
	The Company records derivative instruments in the consolidated balance sheets on a gross basis as either an asset or liability measured at its fair value. Certain of the Company's derivative instruments are subject to right of offset provisions with counterparties. The following tables include the gross amounts related to the Company's derivative portfolio recognized in the consolidated balance sheets, reconciled to the net amount when excluding derivatives subject to enforceable master netting arrangements and cash collateral received/pledged:
							Gross amounts not offset in the consolidated balance sheets
	Derivative assets		Gross amounts of recognized assets presented in the consolidated balance sheets				Derivatives subject to enforceable master netting arrangement			Cash collateral received			Net asset (liability)
Balance as of September 30, 2014		$	68,009			(11,387	)		—			56,622
Balance as of December 31, 2013		62,507				(15,437	)		(15,959	)		31,111
						Gross amounts not offset in the consolidated balance sheets
Derivative liabilities		Gross amounts of recognized liabilities presented in the consolidated balance sheets				Derivatives subject to enforceable master netting arrangement			Cash collateral pledged (received)			Net asset (liability)
Balance as of September 30, 2014		$	(14,814	)		11,387			(22,422	)		(25,849	)
Balance as of December 31, 2013		(17,969		)		15,437			3,630			1,098
The following table summarizes the effect of derivative instruments in the consolidated statements of income.
	Three months ended September 30,							Nine months ended September 30,
	2014				2013			2014			2013
Settlements:
1:3 basis swaps	$	808			781			2,547			2,474
Interest rate swaps - floor income hedges	(5,421		)		(7,178	)		(19,345	)		(24,017	)
Interest rate swaps - hybrid debt hedges	(259		)		(256	)		(767	)		(1,413	)
Cross-currency interest rate swaps	38				(35	)		288			(273	)
Total settlements - expense	(4,834		)		(6,688	)		(17,277	)		(23,229	)
Change in fair value:
1:3 basis swaps	19,455				(2,161	)		32,475			9,402
Interest rate swaps - floor income hedges	10,628				(9,599	)		11,173			33,231
Interest rate swap option - floor income hedge	(847		)		—			(847	)		—
Interest rate swaps - hybrid debt hedges	(393		)		2,700			(2,971	)		11,790
Cross-currency interest rate swaps	(37,224		)		39,074			(40,261	)		18,978
Other	—				—			—			342
Total change in fair value - income (expense)	(8,381		)		30,014			(431	)		73,743
Re-measurement of Euro Notes (foreign currency transaction adjustment) - income (expense)	37,418				(39,974	)		39,216			(25,902	)
Derivative market value and foreign currency adjustments and derivative settlements, net - income (expense)	$	24,203			(16,648	)		21,508			24,612

Investments

Investments	9 Months Ended
	Sep. 30, 2014
Investments [Abstract]	'
Investments	'
	Investments
	A summary of the Company's investments and restricted investments follows:
		As of September 30, 2014													As of December 31, 2013
		Amortized cost				Gross unrealized gains			Gross unrealized losses (a)			Fair value			Amortized cost	Gross unrealized gains	Gross unrealized losses		Fair value
	Investments:
	Available-for-sale investments:
	Student loan asset-backed and other debt securities (b)	$	123,898			6,309			(153	)		130,054			171,931	7,111	(1,241	)	177,801
	Equity securities	1,478				1,959			(21	)		3,416			1,502	1,783	(3	)	3,282
	Total available-for-sale investments	$	125,376			8,268			(174	)		133,470			173,433	8,894	(1,244	)	181,083
	Trading investments:
	Student loan asset-backed securities											5,370							10,957
	Equity securities											8,940							—
	Total trading investments											14,310							10,957
	Total available-for-sale and trading investments											$	147,780						192,040
	Restricted Investments (c):
	Guaranteed investment contracts - held-to-maturity											$	8,205						7,285
	(a)	As of September 30, 2014, the Company considered the decline in market value of its available-for-sale investments to be temporary in nature and did not consider any of its investments other-than-temporarily impaired.
	(b)	As of September 30, 2014, the stated maturities of the majority of the Company's student loan asset-backed and other debt securities classified as available-for-sale were greater than 10 years.
	(c)	Restricted investments are included in "restricted cash and investments" in the Company's consolidated balance sheets.
	The amounts reclassified from accumulated other comprehensive income related to the realized gains and losses on available-for-sale-securities is summarized below.
			Three months ended September 30,							Nine months ended September 30,
	Affected line item in the consolidated statements of income - income (expense):		2014				2013			2014			2013
	Other income		$	8			730			8,319			2,246
	Income tax expense		(3		)		(270	)		(3,078	)		(831	)
	Net		$	5			460			5,241			1,415

Business_Combination_Notes

Business Combination (Notes)	9 Months Ended
	Sep. 30, 2014
Business Combinations [Abstract]	'
Business Combination Disclosure [Text Block]	'
	Business Combination
	The Company uses the acquisition method in accounting for acquired businesses. Under the acquisition method, the financial statements reflect the operations of an acquired business starting from the completion of the acquisition. The assets acquired and liabilities assumed are recorded at their respective estimated fair values at the date of acquisition. Any excess of the purchase price over the estimated fair values of the identifiable net assets acquired is recorded as goodwill. All contingent consideration is measured at fair value on the acquisition date and included in the consideration transferred in the acquisition. Contingent consideration classified as a liability is remeasured to fair value at each reporting date until the contingency is resolved, and changes in fair value are recognized in earnings.
	Wilcomp Software, L.P. (d.b.a. RenWeb School Management Software) (“RenWeb”)
	On June 3, 2014, the Company purchased 100 percent of the ownership interests of RenWeb. RenWeb provides school information systems for private and faith-based schools that help schools automate administrative processes such as admissions, scheduling, student billing, attendance, and grade book management. The combination of RenWeb’s school administration software and the Company’s tuition management and financial needs assessment services are expected to significantly increase the value of the Company’s offerings in this area, allowing the Company to deliver a comprehensive suite of solutions to schools.
	The initial consideration paid by the Company for RenWeb was $44.0 million. In addition to the initial purchase price, additional payments are to be paid by the Company to the former owners of RenWeb based on certain operating results and other performance measures of RenWeb as defined in the purchase agreement. The contingent payments, if any, are payable when earned and the potential undiscounted amount of all future payments that the Company could be required to make under the contingent consideration arrangement is between $0 and $4.0 million. Such payments, if any, will be paid no later than January 2017. As of the acquisition date, the Company accrued $2.3 million as additional consideration, which represented the estimated fair value of the contingent consideration arrangement. From the acquisition date through September 30, 2014, there has been no change in the estimated fair value of the contingent consideration.
	The following table summarizes the estimated fair values of the assets acquired and liabilities assumed at the acquisition date.
	Cash and cash equivalents	$	326
	Accounts receivable	961
	Property and equipment	105
	Other assets	22
	Intangible assets	37,188
	Excess cost over fair value of net assets acquired (goodwill)	9,082
	Other liabilities	(1,341		)
	Net assets acquired	$	46,343
	The $37.2 million of acquired intangible assets on the date of acquisition had a weighted-average useful life of approximately 18 years. The intangible assets that made up this amount included customer relationships of $25.5 million (20-year useful life), trade name of $6.4 million (20-year useful life), computer software of $4.9 million (5-year useful life), and non-competition agreements of $0.4 million (10-year useful life).
	The $9.1 million of goodwill was assigned to the Tuition Payment Processing and Campus Commerce operating segment and is expected to be deductible for tax purposes. The amount allocated to goodwill was primarily attributable to anticipated synergies as discussed previously.
	The proforma impacts of the acquisition on the Company's historical results prior to the acquisition were not material.

Intangible_Assets_Intangible_A

Intangible Assets Intangible Assets	9 Months Ended
	Sep. 30, 2014
Intangible Assets, Net (Excluding Goodwill) [Abstract]	'
Intangible Assets Disclosure [Text Block]	'
	Intangible Assets
	Intangible assets consist of the following:
		Weighted average remaining useful life as of September 30, 2014 (months)		As of September 30, 2014		As of December 31, 2013
	Amortizable intangible assets:
	Customer relationships (net of accumulated amortization of $22,866 and $19,821, respectively)	207		$	28,612	6,132
	Computer software (net of accumulated amortization of $1,210 and $0, respectively)	44		7,656		—
	Trade names (net of accumulated amortization of $156 and $0, respectively)	236		6,266		—
	Covenants not to compete (net of accumulated amortization of $12 and $0, respectively)	116		342		—
	Total - amortizable intangible assets	181		$	42,876	6,132
	The Company recorded amortization expense on its intangible assets of $2.0 million and $0.8 million during the three months ended September 30, 2014 and 2013, respectively, and $4.4 million and $2.5 million during the nine months ended September 30, 2014 and 2013, respectively. The Company will continue to amortize intangible assets over their remaining useful lives. As of September 30, 2014 the Company estimates it will record amortization expense as follows:
	2014 (Q4)	$	1,984
	2015	8,695
	2016	5,349
	2017	3,862
	2018	3,533
	2019 and thereafter	19,453
		$	42,876

Goodwill_Goodwill

Goodwill Goodwill	9 Months Ended
	Sep. 30, 2014
Goodwill and Intangible Assets Disclosure [Abstract]	'
Goodwill Disclosure [Text Block]	'
	Goodwill
	The change in the carrying amount of goodwill by operating segment was as follows:
		Student Loan and Guaranty Servicing		Tuition Payment Processing and Campus Commerce	Enrollment Services	Asset Generation and Management	Total
	Balance as of December 31, 2013	$	8,596	58,086	8,553	41,883	117,118
	Goodwill acquired during the period	—		9,082	—	—	9,082
	Balance as of September 30, 2014	$	8,596	67,168	8,553	41,883	126,200

Earnings_per_Common_Share

Earnings per Common Share	9 Months Ended
	Sep. 30, 2014
Earnings Per Share [Abstract]	'
Earnings Per Common Share	'
	Earnings per Common Share
	Presented below is a summary of the components used to calculate basic and diluted earnings per share. The Company applies the two-class method in computing both basic and diluted earnings per share, which requires the calculation of separate earnings per share amounts for common stock and unvested share based awards. Unvested share-based awards that contain nonforfeitable rights to dividends are considered securities which participate in undistributed earnings with common stock.
		Three months ended September 30,
		2014				2013
		Common shareholders		Unvested restricted stock shareholders	Total	Common shareholders	Unvested restricted stock shareholders	Total
	Numerator:
	Net income attributable to Nelnet, Inc.	$	84,330	889	85,219	62,277	553	62,830
	Denominator:
	Weighted-average common shares outstanding - basic and diluted	45,948,255		484,425	46,432,680	46,086,743	409,869	46,496,612
	Earnings per share - basic and diluted	$	1.84	1.84	1.84	1.35	1.35	1.35
		Nine months ended September 30,
		2014				2013
		Common shareholders		Unvested restricted stock shareholders	Total	Common shareholders	Unvested restricted stock shareholders	Total
	Numerator:
	Net income attributable to Nelnet, Inc.	$	231,725	2,274	233,999	230,141	2,011	232,152
	Denominator:
	Weighted-average common shares outstanding - basic and diluted	46,044,429		451,880	46,496,309	46,189,200	404,041	46,593,241
	Earnings per share - basic and diluted	$	5.03	5.03	5.03	4.98	4.98	4.98
	Unvested restricted stock awards are the Company's only potential common shares and, accordingly, there were no awards that were antidilutive and not included in average shares outstanding for the diluted earnings per share calculation.

Segment_Reporting

Segment Reporting	9 Months Ended
	Sep. 30, 2014
Segment Reporting [Abstract]	'
Segment Reporting	'
	Segment Reporting
	See note 1 of the notes to consolidated financial statements included in the 2013 Annual Report for a description of the Company's operating segments. The following tables include the results of each of the Company's operating segments reconciled to the consolidated financial statements.
		Three months ended September 30, 2014
		Fee-Based
		Student Loan and Guaranty Servicing			Tuition Payment Processing and Campus Commerce		Enrollment		Total Fee-		Asset		Corporate		Eliminations		Total
							Services		Based		Generation and		Activity
											Management		and
													Overhead
	Total interest income	$	5		2		—		7		187,949		1,814		(346	)	189,424
	Interest expense	—			—		—		—		71,037		1,246		(346	)	71,937
	Net interest income	5			2		—		7		116,912		568		—		117,487
	Less provision for loan losses	—			—		—		—		2,000		—		—		2,000
	Net interest income after provision for loan losses	5			2		—		7		114,912		568		—		115,487
	Other income:
	Loan and guaranty servicing revenue	52,659			—		—		52,659		—		—		—		52,659
	Intersegment servicing revenue	13,432			—		—		13,432		—		—		(13,432	)	—
	Tuition payment processing and campus commerce revenue	—			26,399		—		26,399		—		—		—		26,399
	Enrollment services revenue	—			—		22,936		22,936		—		—		—		22,936
	Other income	—			—		—		—		4,294		3,356		—		7,650
	Gain on sale of loans and debt repurchases	—			—		—		—		—		—		—		—
	Derivative market value and foreign currency adjustments, net	—			—		—		—		29,430		(393	)	—		29,037
	Derivative settlements, net	—			—		—		—		(4,575	)	(259	)	—		(4,834	)
	Total other income	66,091			26,399		22,936		115,426		29,149		2,704		(13,432	)	133,847
	Operating expenses:
	Salaries and benefits	37,062			13,288		4,474		54,824		565		5,709		—		61,098
	Cost to provide enrollment services	—			—		14,178		14,178		—		—		—		14,178
	Depreciation and amortization	2,558			2,396		41		4,995		—		498		—		5,493
	Other	15,028			3,312		1,624		19,964		8,636		8,076		—		36,676
	Intersegment expenses, net	906			1,481		761		3,148		13,611		(3,327	)	(13,432	)	—
	Total operating expenses	55,554			20,477		21,078		97,109		22,812		10,956		(13,432	)	117,445
	Income (loss) before income taxes and corporate overhead allocation	10,542			5,924		1,858		18,324		121,249		(7,684	)	—		131,889
	Corporate overhead allocation	(2,567		)	(856	)	(855	)	(4,278	)	(1,026	)	5,304		—		—
	Income (loss) before income taxes	7,975			5,068		1,003		14,046		120,223		(2,380	)	—		131,889
	Income tax (expense) benefit	(3,030		)	(1,926	)	(381	)	(5,337	)	(45,684	)	4,508		—		(46,513	)
	Net income	4,945			3,142		622		8,709		74,539		2,128		—		85,376
	Net income attributable to noncontrolling interest	—			—		—		—		—		157		—		157
	Net income attributable to Nelnet, Inc.	$	4,945		3,142		622		8,709		74,539		1,971		—		85,219
		Three months ended September 30, 2013
		Fee-Based
		Student Loan and Guaranty Servicing			Tuition Payment Processing and Campus Commerce		Enrollment		Total Fee-		Asset		Corporate		Eliminations		Total
							Services		Based		Generation and		Activity
											Management		and
													Overhead
	Total interest income	$	10		—		—		10		158,793		2,201		(767	)	160,237
	Interest expense	—			—		—		—		56,100		(18	)	(767	)	55,315
	Net interest income	10			—		—		10		102,693		2,219		—		104,922
	Less provision for loan losses	—			—		—		—		5,000		—		—		5,000
	Net interest income after provision for loan losses	10			—		—		10		97,693		2,219		—		99,922
	Other income:
	Loan and guaranty servicing revenue	64,582			—		—		64,582		—		—		—		64,582
	Intersegment servicing revenue	13,519			—		—		13,519		—		—		(13,519	)	—
	Tuition payment processing and campus commerce revenue	—			19,927		—		19,927		—		—		—		19,927
	Enrollment services revenue	—			—		22,563		22,563		—		—		—		22,563
	Other income	—			—		—		—		3,981		4,632		—		8,613
	Gain on sale of loans and debt repurchases	—			—		—		—		2,138		—		—		2,138
	Derivative market value and foreign currency adjustments, net	—			—		—		—		(12,660	)	2,700		—		(9,960	)
	Derivative settlements, net	—			—		—		—		(6,432	)	(256	)	—		(6,688	)
	Total other income	78,101			19,927		22,563		120,591		(12,973	)	7,076		(13,519	)	101,175
	Operating expenses:
	Salaries and benefits	29,719			9,229		4,491		43,439		555		4,718		—		48,712
	Cost to provide enrollment services	—			—		14,668		14,668		—		—		—		14,668
	Depreciation and amortization	2,677			1,117		57		3,851		—		489		—		4,340
	Other	19,752			1,908		1,556		23,216		7,939		8,732		—		39,887
Intersegment expenses, net	1,457			1,431		1,139		4,027		13,705		(4,213	)	(13,519	)	—
Total operating expenses	53,605			13,685		21,911		89,201		22,199		9,726		(13,519	)	107,607
Income (loss) before income taxes and corporate overhead allocation	24,506			6,242		652		31,400		62,521		(431	)	—		93,490
Corporate overhead allocation	(1,822		)	(607	)	(607	)	(3,036	)	(1,302	)	4,338		—		—
Income before income taxes	22,684			5,635		45		28,364		61,219		3,907		—		93,490
Income tax (expense) benefit	(8,620		)	(2,141	)	(17	)	(10,778	)	(23,263	)	3,597		—		(30,444	)
Net income	14,064			3,494		28		17,586		37,956		7,504		—		63,046
Net income attributable to noncontrolling interest	—			—		—		—		—		216		—		216
Net income attributable to Nelnet, Inc.	$	14,064		3,494		28		17,586		37,956		7,288		—		62,830
	Nine months ended September 30, 2014
	Fee-Based
	Student Loan and Guaranty Servicing			Tuition Payment Processing and Campus Commerce		Enrollment		Total Fee-		Asset		Corporate		Eliminations		Total
						Services		Based		Generation and		Activity
										Management		and
												Overhead
Total interest income	$	25		5		—		30		520,514		6,508		(1,805	)	525,247
Interest expense	—			—		—		—		198,449		4,532		(1,805	)	201,176
Net interest income	25			5		—		30		322,065		1,976		—		324,071
Less provision for loan losses	—			—		—		—		6,000		—		—		6,000
Net interest income after provision for loan losses	25			5		—		30		316,065		1,976		—		318,071
Other income:
Loan and guaranty servicing revenue	183,876			—		—		183,876		—		—		—		183,876
Intersegment servicing revenue	41,453			—		—		41,453		—		—		(41,453	)	—
Tuition payment processing and campus commerce revenue	—			73,468		—		73,468		—		—		—		73,468
Enrollment services revenue	—			—		65,092		65,092		—		—		—		65,092
Other income	—			—		—		—		12,954		28,142		—		41,096
Gain on sale of loans and debt repurchases	—			—		—		—		57		—		—		57
Derivative market value and foreign currency adjustments, net	—			—		—		—		41,755		(2,970	)	—		38,785
Derivative settlements, net	—			—		—		—		(16,510	)	(767	)	—		(17,277	)
Total other income	225,329			73,468		65,092		363,889		38,256		24,405		(41,453	)	385,097
Operating expenses:
Salaries and benefits	102,462			34,427		12,986		149,875		1,744		15,851		—		167,470
Cost to provide enrollment services	—			—		41,964		41,964		—		—		—		41,964
Depreciation and amortization	8,166			5,669		129		13,964		—		1,526		—		15,490
Other	53,295			8,915		4,917		67,127		24,627		20,926		—		112,680
Intersegment expenses, net	3,113			4,305		2,711		10,129		41,950		(10,626	)	(41,453	)	—
Total operating expenses	167,036			53,316		62,707		283,059		68,321		27,677		(41,453	)	337,604
Income (loss) before income taxes and corporate overhead allocation	58,318			20,157		2,385		80,860		286,000		(1,296	)	—		365,564
Corporate overhead allocation	(6,487		)	(2,163	)	(2,162	)	(10,812	)	(3,604	)	14,416		—		—
Income before income taxes	51,831			17,994		223		70,048		282,396		13,120		—		365,564
Income tax (expense) benefit	(19,695		)	(6,837	)	(85	)	(26,617	)	(107,309	)	3,724		—		(130,202	)
Net income	32,136			11,157		138		43,431		175,087		16,844		—		235,362
Net income attributable to noncontrolling interest	—			—		—		—		—		1,363		—		1,363
Net income attributable to Nelnet, Inc.	$	32,136		11,157		138		43,431		175,087		15,481		—		233,999
	Nine months ended September 30, 2013
	Fee-Based
	Student Loan and Guaranty Servicing			Tuition Payment Processing and Campus Commerce		Enrollment		Total Fee-		Asset		Corporate		Eliminations		Total
						Services		Based		Generation and		Activity
										Management		and
												Overhead
Total interest income	$	29		—		—		29		472,622		6,708		(2,420	)	476,939
Interest expense	—			—		—		—		170,502		3,718		(2,420	)	171,800
Net interest income	29			—		—		29		302,120		2,990		—		305,139
Less provision for loan losses	—			—		—		—		15,000		—		—		15,000
Net interest income after provision for loan losses	29			—		—		29		287,120		2,990		—		290,139
Other income:
Loan and guaranty servicing revenue	180,261			—		—		180,261		—		—		—		180,261
Intersegment servicing revenue	42,375			—		—		42,375		—		—		(42,375	)	—
Tuition payment processing and campus commerce revenue	—			61,694		—		61,694		—		—		—		61,694
Enrollment services revenue	—			—		76,343		76,343		—		—		—		76,343
Other income	—			—		—		—		11,207		19,110		—		30,317
Gain on sale of loans and debt repurchases	—			—		—		—		10,900		—		—		10,900
Derivative market value and foreign currency adjustments, net	—			—		—		—		35,711		12,130		—		47,841
Derivative settlements, net	—			—		—		—		(21,816	)	(1,413	)	—		(23,229	)
Total other income	222,636			61,694		76,343		360,673		36,002		29,827		(42,375	)	384,127
Operating expenses:
Salaries and benefits	86,254			28,015		15,067		129,336		1,709		13,004		—		144,049
Cost to provide enrollment services	—			—		51,097		51,097		—		—		—		51,097
Depreciation and amortization	8,197			3,387		179		11,763		—		1,274		—		13,037
Other	56,173			6,387		4,450		67,010		23,375		18,808		—		109,193
Intersegment expenses, net	3,243			4,350		3,418		11,011		42,955		(11,591	)	(42,375	)	—
Total operating expenses	153,867			42,139		74,211		270,217		68,039		21,495		(42,375	)	317,376
Income before income taxes and corporate overhead allocation	68,798			19,555		2,132		90,485		255,083		11,322		—		356,890
Corporate overhead allocation	(4,332		)	(1,443	)	(1,443	)	(7,218	)	(3,095	)	10,313		—		—
Income before income taxes	64,466			18,112		689		83,267		251,988		21,635		—		356,890
Income tax (expense) benefit	(24,498		)	(6,882	)	(261	)	(31,641	)	(95,755	)	3,759		—		(123,637	)
Net income	39,968			11,230		428		51,626		156,233		25,394		—		233,253
Net income attributable to noncontrolling interest	—			—		—		—		—		1,101		—		1,101
Net income attributable to Nelnet, Inc.	$	39,968		11,230		428		51,626		156,233		24,293		—		232,152

Major_Customer

Major Customer	9 Months Ended
	Sep. 30, 2014
Risks and Uncertainties [Abstract]	'
Concentration Risk Disclosure [Text Block]	'
	Major Customer
	The Company is one of four private sector companies awarded a student loan servicing contract by the Department of Education (the "Department") in June 2009 to provide additional servicing capacity for loans owned by the Department, with new loan volume currently being allocated among the four servicers based on certain performance metrics established by the Department. The servicing contract was originally scheduled to expire in June 2014. Effective as of June 17, 2014, the Department extended the servicing contract for an additional five years through June 16, 2019. Revenue earned by the Company's Student Loan and Guaranty Servicing operating segment related to this contract was $31.2 million and $26.0 million for the three months ended September 30, 2014 and 2013, respectively, and $92.1 million and $68.4 million for the nine months ended September 30, 2014 and 2013, respectively.

Related_Party_Transactions

Related Party Transactions	9 Months Ended
	Sep. 30, 2014
Related Party Transactions [Abstract]	'
Related Party Transactions	'
	Related Party Transactions
	The Company has entered into certain contractual arrangements with related parties as described in note 19 of the notes to consolidated financial statements included in the 2013 Annual Report.  The following provides an update for a related party transaction that occurred during the first nine months of 2014.
	On January 1, 2014, the Company subparticipated the Company's participation interest in a loan receivable from an unrelated third party to Union Bank and Trust Company ("Union Bank"), an entity under common control with the Company. As of September 30, 2014, the participated portion of the loan was $2.2 million, with an obligation to fund an additional $0.9 million. As part of this agreement, Union Bank will pay the Company monthly servicing fees equal to 40 basis points on the participated portion of the outstanding principal balance of the loan.

Fair_Value

Fair Value	9 Months Ended
	Sep. 30, 2014
Fair Value Disclosures [Abstract]	'
Fair Value	'
	Fair Value
	The following tables present the Company’s financial assets and liabilities that are measured at fair value on a recurring basis. There were no transfers into or out of level 1, level 2, or level 3 for the nine months ended September 30, 2014.
		As of September 30, 2014				As of December 31, 2013
		Level 1		Level 2	Total	Level 1	Level 2	Total
	Assets:
	Investments:
	Student loan asset-backed securities	$	—	143,955	143,955	—	188,279	188,279
	Equity securities	3,416		—	3,416	3,282	—	3,282
	Debt securities	409		—	409	479	—	479
	Total investments	3,825		143,955	147,780	3,761	188,279	192,040
	Fair value of derivative instruments	—		68,009	68,009	—	62,507	62,507
	Total assets	$	3,825	211,964	215,789	3,761	250,786	254,547
	Liabilities:
	Fair value of derivative instruments	$	—	14,814	14,814	—	17,969	17,969
	Total liabilities	$	—	14,814	14,814	—	17,969	17,969
	The following table summarizes the fair values of all of the Company’s financial instruments on the consolidated balance sheets:
		As of September 30, 2014
		Fair value		Carrying value	Level 1	Level 2	Level 3
	Financial assets:
	Student loans receivable	$	29,975,188	28,701,344	—	—	29,975,188
	Cash and cash equivalents	74,579		74,579	74,579	—	—
	Investments	147,780		147,780	3,825	143,955	—
	Restricted cash	859,302		859,302	859,302	—	—
	Restricted cash – due to customers	72,836		72,836	72,836	—	—
	Restricted investments	8,205		8,205	8,205	—	—
	Accrued interest receivable	352,205		352,205	—	352,205	—
	Derivative instruments	68,009		68,009	—	68,009	—
	Financial liabilities:
	Bonds and notes payable	28,738,353		28,737,456	—	28,738,353	—
	Accrued interest payable	25,221		25,221	—	25,221	—
	Due to customers	72,836		72,836	72,836	—	—
	Derivative instruments	14,814		14,814	—	14,814	—
		As of December 31, 2013
		Fair value		Carrying value	Level 1	Level 2	Level 3
	Financial assets:
	Student loans receivable	$	26,641,383	25,907,589	—	—	26,641,383
	Cash and cash equivalents	63,267		63,267	63,267	—	—
	Investments	192,040		192,040	3,761	188,279	—
	Restricted cash	727,838		727,838	727,838	—	—
	Restricted cash – due to customers	167,576		167,576	167,576	—	—
	Restricted investments	7,285		7,285	7,285	—	—
	Accrued interest receivable	314,553		314,553	—	314,553	—
	Derivative instruments	62,507		62,507	—	62,507	—
	Financial liabilities:
	Bonds and notes payable	25,577,250		25,955,289	—	25,577,250	—
	Accrued interest payable	21,725		21,725	—	21,725	—
	Due to customers	167,576		167,576	167,576	—	—
	Derivative instruments	17,969		17,969	—	17,969	—
	The methodologies for estimating the fair value of financial assets and liabilities are described in note 20 of the notes to consolidated financial statements included in the 2013 Annual Report.

Legal_Proceedings

Legal Proceedings	9 Months Ended
	Sep. 30, 2014
Commitments and Contingencies Disclosure [Abstract]	'
Legal Proceedings	'
	Legal Proceedings
	General
	The Company is subject to various legal proceedings that arise in the normal course of business, including the legal proceedings discussed below. These matters frequently involve claims by student loan borrowers disputing the manner in which their student loans have been serviced or the accuracy of reports to credit bureaus, claims by student loan borrowers or other consumers alleging that state or Federal consumer protection laws have been violated in the process of collecting loans or conducting other business activities, and disputes with other business entities. From time to time, lawsuits may be brought as, or subsequently amended to assert claims in the form of, putative class action cases.
	In evaluating each of its legal proceedings, the Company considers many factors that involve significant risks and uncertainties inherent in the overall litigation process, including (i) the amount of damages and the nature of any other relief sought in the proceeding, if specified; (ii) whether the proceeding is at an early stage; (iii) the impact of discovery; (iv) whether novel or unsettled legal theories are at issue; (v) the outcome of pending motions or appeals; (vi) whether there are significant factual issues to be resolved; (vii) whether class action status is sought and the Company's views of the likelihood of a class being certified by the court and the ultimate size of the class; (viii) the jurisdiction in which the proceeding is pending; (ix) the Company's views of the merits of the claims and of the strength of the Company's defenses; and (x) the progress of any negotiations with opposing parties. In assessing whether a legal proceeding may be material, the Company considers these and other quantitative and qualitative factors, including whether disclosure of the proceeding might be important to a reader of the Company's financial statements in light of all of the information about the Company that is available to the reader.
	Actions Requesting Certifications of Classes
	Proceedings or complaints that involve or ask for certifications of classes generally expand the scope of legal defense costs, as well as alleged potential claim amounts. The Company is currently subject to legal proceedings in which the plaintiffs have made allegations that one or more putative classes should be certified by the applicable court. With respect to the three proceedings specifically discussed below, it is significant to note that, no putative class has actually been certified in any of these proceedings, the Company's position is that class certification would be inappropriate in each such proceeding, the Company has entered into agreements in principle to resolve two of the pending matters for immaterial amounts through a court-approved class-wide settlement, and the Company has been granted a motion for a summary judgment dismissing the case and intends to vigorously contest the appeal and class certification in the remaining matter. The Company has accrued an immaterial amount related to the legal proceedings described below. However, due to the uncertainty and risks inherent in class determination and the overall litigation process, the Company believes that a meaningful estimate of its exposure to any reasonably possible losses or range of reasonably possible losses, in excess of the amount accrued, cannot currently be made.
	Bais Yaakov of Spring Valley v. Peterson's Nelnet, LLC
	On January 4, 2011, a complaint against Peterson's Nelnet, LLC (“Peterson's”), a subsidiary of Nelnet, Inc. ("Nelnet"), was filed in the U.S. Federal District Court for the District of New Jersey (the “New Jersey District Court”). The complaint alleges that Peterson's sent six advertising faxes to the named plaintiff in 2008-2009 that were not the result of express invitation or permission granted by the plaintiff and did not include certain opt out language. The complaint also alleges that such faxes violated the Federal Telephone Consumer Protection Act (the “TCPA”), purportedly entitling the plaintiff to $500 per violation, trebled for willful violations for each of the six faxes. The complaint further alleges that Peterson's had sent putative class members more than 10,000 faxes that violated the TCPA, amounting to more than $5 million in statutory penalty damages and more than $15 million if trebled for willful violations. The complaint seeks to establish a class action. On September 13, 2013, the named plaintiff filed a motion for class certification, and on October 7, 2013, Peterson's filed a motion to dismiss the named plaintiff's motion for class certification. As of the filing date of this report, the New Jersey District Court has not established, recognized, or certified a class. On January 23, 2014, Peterson's and the named plaintiff reached an agreement in principle whereby Peterson's would, without admitting any wrongdoing or liability, settle all claims in the lawsuit, including potential class action claims, for payment of an immaterial amount. The settlement agreement in principle is subject to finalization and court approval.
	Than Zaw v. Nelnet, Inc.
	On January 18, 2013, a Third Amended Complaint was served on Nelnet in connection with a lawsuit by Than Zaw against Nelnet (erroneously referred to in the lawsuit as Nelnet Business Solutions, Inc.) in the Superior Court of the State of California, Contra Costa County. The case has since been moved to the U.S. Federal District Court for the Northern District of California (the “California District Court”). The lawsuit was originally instituted on December 30, 2010, and alleges that Nelnet violated the California Fair Debt Collection Practices Act in its interactions with the plaintiff, a California resident. The plaintiff's Third Amended Complaint added additional allegations claiming that Nelnet violated Section 632 of the California Penal Code by allegedly recording one or more telephone calls to the plaintiff without the plaintiff's consent, and sought $5,000 in statutory damages per alleged violation. The Third Amended Complaint further alleged that Nelnet improperly recorded telephone calls to other California residents without such persons' consent, and sought to establish a class action with respect to the California Section 632 claim. As of the filing date of this report, the California District Court has not established, recognized, or certified a class. On October 16, 2013, Nelnet and the named plaintiff reached an agreement in principle whereby Nelnet would, without admitting any wrongdoing or liability, settle all claims in the lawsuit, including potential class action claims, for payment of an immaterial amount. The settlement agreement in principle is subject to finalization and court approval.
	Grant Keating v. Peterson's Nelnet, LLC et al
	On August 6, 2012, an Amended Complaint was served on Peterson's, CUnet, LLC (“CUnet”), a subsidiary of Nelnet, and on Nelnet (collectively, the "Keating Defendants"), in connection with a lawsuit by Grant Keating in the U.S. Federal District Court for the Northern District of Ohio (the “Ohio District Court”). The lawsuit was originally instituted on August 24, 2011, and alleges that the Keating Defendants sent an advertising text message to the named plaintiff in June 2011 using an automatic telephone dialing system, and without the plaintiff's express consent. The complaint also alleges that this text message violated the TCPA, purportedly entitling the plaintiff to $500, trebled for a willful violation. The complaint further alleges that the Keating Defendants sent putative class members similar text messages using an automatic telephone dialing system, without such purported class members' consent. The complaint seeks to establish a class action. On August 29, 2013, the Keating Defendants filed motions for summary judgment, and the named plaintiff filed a motion for class certification. On May 12, 2014, the Ohio District Court granted the Keating Defendants' motion for summary judgment, dismissing the case. On September 8, 2014, the named plaintiff filed an appeal brief with the Circuit Court of Appeals and on October 22, 2014, two Keating Defendants filed a responsive brief. As of the filing date of this report, the Ohio District Court has not established, recognized, or certified a class. The Keating Defendants intend to continue to defend themselves vigorously in this lawsuit.

Basis_of_Financial_Reporting_S

Basis of Financial Reporting Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2014
Organization, Consolidation and Presentation of Financial Statements [Abstract]	'
Basis of Financial Reporting	'
	Basis of Financial Reporting
	The accompanying unaudited consolidated financial statements of Nelnet, Inc. and subsidiaries (the “Company”) as of September 30, 2014 and for the three and nine months ended September 30, 2014 and 2013 have been prepared on the same basis as the audited consolidated financial statements for the year ended December 31, 2013 and, in the opinion of the Company’s management, the unaudited consolidated financial statements reflect all adjustments, consisting of normal recurring adjustments, necessary for a fair presentation of results of operations for the interim periods presented. The preparation of financial statements in conformity with U.S. generally accepted accounting principles 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, 2014 are not necessarily indicative of the results for the year ending December 31, 2014. The unaudited consolidated financial statements should be read in conjunction with the Company’s Annual Report on Form 10-K for the year ended December 31, 2013 (the "2013 Annual Report").

Business_Combination_Business_

Business Combination Business Combination Policy (Policies)	9 Months Ended
	Sep. 30, 2014
Business Combinations [Abstract]	'
Business Combinations Policy [Policy Text Block]	'
	The Company uses the acquisition method in accounting for acquired businesses. Under the acquisition method, the financial statements reflect the operations of an acquired business starting from the completion of the acquisition. The assets acquired and liabilities assumed are recorded at their respective estimated fair values at the date of acquisition. Any excess of the purchase price over the estimated fair values of the identifiable net assets acquired is recorded as goodwill. All contingent consideration is measured at fair value on the acquisition date and included in the consideration transferred in the acquisition. Contingent consideration classified as a liability is remeasured to fair value at each reporting date until the contingency is resolved, and changes in fair value are recognized in earnings.

Student_Loans_Receivable_and_A1

Student Loans Receivable and Allowance for Loan Losses (Tables)	9 Months Ended
	Sep. 30, 2014
Receivables [Abstract]	'
Schedule of Accounts, Notes, Loans and Financing Receivable	'
	Student loans receivable consisted of the following:
		As of			As of
		September 30, 2014			December 31, 2013
	Federally insured loans
	Stafford and other	$	6,218,910		6,686,626
	Consolidation	22,632,689			19,363,577
	Total	28,851,599			26,050,203
	Non-federally insured loans	77,623			71,103
		28,929,222			26,121,306
	Loan discount, net of unamortized loan premiums and deferred origination costs (a)	(175,910		)	(158,595	)
	Allowance for loan losses – federally insured loans	(39,470		)	(43,440	)
	Allowance for loan losses – non-federally insured loans	(12,498		)	(11,682	)
		$	28,701,344		25,907,589
	(a)	For loans purchased where there is evidence of credit deterioration since the origination of the loan, the Company records a credit discount, separate from the allowance for loan losses, which is non-accretable to interest income. Remaining discounts and premiums for purchased loans are recognized in interest income over the remaining estimated lives of the loans. The Company continues to evaluate credit losses associated with purchased loans based on current information and changes in expectations to determine the need for any additional allowance for loan losses. As of September 30, 2014 and December 31, 2013, "loan discount, net of unamortized loan premiums and deferred origination costs" included $28.8 million and $20.2 million, respectively, of non-accretable discount associated with purchased loans of $8.4 billion and $4.4 billion, respectively.
Allowance for Credit Losses on Financing Receivables	'
	Activity in the Allowance for Loan Losses
	The provision for loan losses represents the periodic expense of maintaining an allowance appropriate to absorb losses, net of recoveries, inherent in the portfolio of student loans. Activity in the allowance for loan losses is shown below.
		Three months ended September 30,					Nine months ended September 30,
		2014			2013		2014		2013
	Balance at beginning of period	$	52,467		51,611		55,122		51,902
	Provision for loan losses:
	Federally insured loans	2,000			5,000		7,000		16,000
	Non-federally insured loans	—			—		(1,000	)	(1,000	)
	Total provision for loan losses	2,000			5,000		6,000		15,000
	Charge-offs:
	Federally insured loans	(3,521		)	(3,142	)	(11,290	)	(12,472	)
	Non-federally insured loans	(623		)	(906	)	(1,642	)	(2,270	)
	Total charge-offs	(4,144		)	(4,048	)	(12,932	)	(14,742	)
	Recoveries - non-federally insured loans	279			363		989		1,173
	Purchase (sale) of federally insured loans, net	70			700		320		(1,243	)
	Transfer from repurchase obligation related to non-federally insured loans repurchased, net	1,296			571		2,469		2,107
	Balance at end of period	$	51,968		54,197		51,968		54,197
	Allocation of the allowance for loan losses:
	Federally insured loans	$	39,470		42,406		39,470		42,406
	Non-federally insured loans	12,498			11,791		12,498		11,791
	Total allowance for loan losses	$	51,968		54,197		51,968		54,197
Accrual Related to Repurchase Obligation Rollforward	'
	Repurchase Obligations
	As of September 30, 2014, the Company had participated a cumulative amount of $103.6 million (par value) of non-federally insured loans to third parties. Loans participated under these agreements have been accounted for by the Company as loan sales. Accordingly, the participation interests sold are not included in the Company’s consolidated balance sheets. Per the terms of the servicing agreements, the Company’s servicing operations are obligated to repurchase loans subject to the participation interests in the event such loans become 60 days or 90 days delinquent.
	In addition, in 2011, the Company sold a portfolio of non-federally insured loans for proceeds of $91.3 million (100% of par value).  The Company retained credit risk related to this portfolio and will pay cash to purchase back any loans which become 60 days delinquent. As of September 30, 2014, the balance of this portfolio was $57.0 million (par value).
	The Company’s estimate related to its obligation to repurchase these loans is included in “other liabilities” in the Company’s consolidated balance sheets. The activity related to this accrual is detailed below.
		Three months ended September 30,					Nine months ended September 30,
		2014			2013		2014		2013
	Beginning balance	$	14,827		14,594		16,143		16,130
	Loans repurchased	(1,296		)	(571	)	(2,612	)	(2,107	)
	Ending balance	$	13,531		14,023		13,531		14,023
Financing Receivable Credit Quality Indicators	'
	Student Loan Status and Delinquencies
	Delinquencies have the potential to adversely impact the Company’s earnings through increased servicing and collection costs and account charge-offs.  The percent of non-federally insured loans that were delinquent 31 days or greater as of September 30, 2014, December 31, 2013, and September 30, 2013 was 11.7 percent, 12.7 percent, and 13.4 percent, respectively. The table below shows the Company’s federally insured student loan delinquency amounts.
		As of September 30, 2014					As of December 31, 2013					As of September 30, 2013
	Federally insured loans:
	Loans in-school/grace/deferment	$	3,072,318				$	2,872,505				$	3,039,819
	Loans in forbearance	3,505,103					3,370,025					3,396,748
	Loans in repayment status:
	Loans current	18,672,178			83.8	%	16,337,922			82.5	%	15,236,060		83.1	%
	Loans delinquent 31-60 days	990,696			4.5		967,318			4.9		851,397		4.6
	Loans delinquent 61-90 days	569,879			2.6		550,333			2.8		480,285		2.6
	Loans delinquent 91-120 days	452,463			2		390,791			2		372,697		2
	Loans delinquent 121-270 days	1,183,616			5.3		1,117,936			5.6		978,234		5.3
	Loans delinquent 271 days or greater	405,346			1.8		443,373			2.2		437,337		2.4
	Total loans in repayment	22,274,178			100	%	19,807,673			100	%	18,356,010		100	%
	Total federally insured loans	$	28,851,599				$	26,050,203				$	24,792,577

Bonds_and_Notes_payable_Tables

Bonds and Notes payable (Tables)	9 Months Ended
	Sep. 30, 2014
Bonds and Notes Payable [Abstract]	'
Schedule of Debt	'
	The following tables summarize the Company’s outstanding debt obligations by type of instrument:
		As of September 30, 2014
		Carrying				Interest rate		Final maturity
		amount				range
	Variable-rate bonds and notes issued in asset-backed securitizations:
	Bonds and notes based on indices	$	26,639,879			0.24% - 6.90%		5/25/18 - 8/26/52
	Bonds and notes based on auction or remarketing	1,557,875				0.07% - 2.11%		5/1/28 - 11/26/46
	Total variable-rate bonds and notes	28,197,754
	FFELP warehouse facilities	787,042				0.16% - 0.25%		1/17/16 - 6/11/17
	Unsecured line of credit	—				—		6/30/19
	Unsecured debt - Junior Subordinated Hybrid Securities	96,457				3.61%		9/15/61
	Other borrowings	63,504				1.66% - 5.10%		11/14/14 - 12/31/18
		29,144,757
	Discount on bonds and notes payable	(407,301		)
	Total	$	28,737,456
		As of December 31, 2013
		Carrying				Interest rate		Final maturity
		amount				range
	Variable-rate bonds and notes issued in asset-backed securitizations:
	Bonds and notes based on indices	$	23,479,893			0.25% - 6.90%		5/25/18 - 8/26/52
	Bonds and notes based on auction or remarketing	1,134,250				0.07% - 2.17%		5/1/28 - 11/26/46
	Total variable-rate bonds and notes	24,614,143
	FFELP warehouse facilities	1,396,344				0.17% - 0.25%		1/17/16 - 6/12/16
	Unsecured line of credit	45,000				1.67%		3/28/18
	Unsecured debt - Junior Subordinated Hybrid Securities	96,457				3.62%		9/15/61
	Other borrowings	61,401				1.67% - 5.10%		4/11/14 - 11/11/15
		26,213,345
	Discount on bonds and notes payable	(258,056		)
	Total	$	25,955,289
Schedule of Line of Credit Facilities	'
	FFELP Warehouse Facilities
	The Company funds a portion of its FFELP loan acquisitions using its FFELP warehouse facilities. Student loan warehousing allows the Company to buy and manage student loans prior to transferring them into more permanent financing arrangements.
	As of September 30, 2014, the Company had three FFELP warehouse facilities as summarized below.
			NHELP-III				NHELP-II (a)		NFSLW-I (b)		Total
	Maximum financing amount		$	750,000			500,000		500,000		1,750,000
	Amount outstanding		438,265				40,433		308,344		787,042
	Amount available		$	311,735			459,567		191,656		962,958
	Expiration of liquidity provisions		February 5, 2015				December 17, 2014		June 11, 2015
	Final maturity date		January 17, 2016				December 17, 2016		June 11, 2017
	Maximum advance rates		92.2 - 95.0%				84.5 - 94.5%		92.0 - 98.0%
	Minimum advance rates		92.2 - 95.0%				84.5 - 94.5%		84.0 - 90.0%
	Advanced as equity support		$	26,264			4,195		14,778		45,237
Schedule of asset-backed securitizations [Table Text Block]	'
	Asset-backed Securitizations
	The following table summarizes the asset-backed securitization transactions completed during the nine months ended September 30, 2014.
			2014-1				2014-2								2014-3		2014-4						2014-5		2014-6 (a)		Total
							Class A-1 notes		Class A-2 notes		Class A-3 notes		2014-2 total				Class A-1 notes		Class A-2 notes		2014-4 total
	Date securities issued		2/6/14				3/12/14		3/12/14		3/12/14		3/12/14		4/30/14		5/23/14		5/23/14		5/23/14		6/18/14		7/31/14
	Total original principal amount		$	458,500									509,000		719,800						384,500		603,000		565,000		$	3,239,800
	Class A senior notes:
	Total original principal amount		$	445,000			191,000		222,000		84,000		497,000		700,700		267,500		107,500		375,000		587,000		565,000		3,169,700
	Bond discount		—				—		—		(535	)	(535	)	—		—		—		—		—		(3,124	)	(3,659		)
	Issue price		$	445,000			191,000		222,000		83,465		496,465		700,700		267,500		107,500		375,000		587,000		561,876		3,166,041
	Cost of funds (1-month LIBOR plus:)		0.57		%		0.28	%	0.6	%	0.85	%			0.58	%	0.54	%	0.95	%			0.55	%	0.65	%
	Final maturity date		9/25/41				6/25/21		3/25/30		7/27/37				6/25/41		11/27/34		11/25/43				7/25/41		11/25/47
	Class B subordinated notes:
	Total original principal amount		$	13,500									12,000		19,100						9,500		16,000				70,100
	Bond discount		(1,132		)								(1,046	)	(1,467	)					(1,138	)	(1,232	)			(6,015		)
	Issue price		$	12,368									10,954		17,633						8,362		14,768				64,085
	Cost of funds (1-month LIBOR plus:)		1.5		%								1.5	%	1.5	%					1.5	%	1.5	%
	Final maturity date		10/25/47										6/25/41		10/25/50						9/25/51		5/25/49
	(a)	Total original principal amount excludes the Class B subordinated notes of $8.3 million that were retained at issuance. As of September 30, 2014, the Company has a total of $64.6 million (par value) of its own Class B subordinated notes remaining from prior completed asset-backed securitizations that are not included in the Company's consolidated balance sheet. If the Company sells these notes to third parties, the Company would obtain cash proceeds equal to the market value of the notes on the date of such sale.  Upon sale, these notes would be shown as “bonds and notes payable” in the Company's consolidated balance sheet.  The Company believes the market value of such notes is currently less than par value.  Any excess of the par value over the market value on the date of sale would be recognized by the Company as interest expense over the life of the bonds.

Derivative_Financial_Instrumen1

Derivative Financial Instruments (Tables)	9 Months Ended
	Sep. 30, 2014
Derivative Instruments and Hedging Activities Disclosure [Abstract]	'
Interest Rate Swaps - 1:3 Basis swaps	'
	Basis Swaps
	The following table summarizes the Company’s basis swaps outstanding as of September 30, 2014 and December 31, 2013 in which the Company receives three-month LIBOR set discretely in advance and pays one-month LIBOR plus or minus a spread as defined in the agreements (the "1:3 Basis Swaps").
		Maturity			Notional amount
		2021			$	250,000
		2022			1,900,000
		2023			3,650,000
		2024			250,000
		2026			800,000
		2028			100,000
		2036			700,000
		2039	(a)		150,000
		2040	(b)		200,000
					$	8,000,000		(c)
	(a)This derivative has a forward effective start date in 2015.
	(b)This derivative has a forward effective start date in 2020.
	(c)	The weighted average rate paid by the Company on the 1:3 Basis Swaps as of September 30, 2014 and December 31, 2013 was one-month LIBOR plus 3.5 basis points
Interest Rate Swaps - Floor Income Hedges	'
	Interest Rate Swaps – Floor Income Hedges
	The following table summarizes the outstanding derivative instruments used by the Company to economically hedge loans earning fixed rate floor income.
			As of September 30, 2014							As of December 31, 2013
	Maturity		Notional amount				Weighted average fixed rate paid by the Company (a)			Notional amount				Weighted average fixed rate paid by the Company (a)
	2014		$	—			—	%		$	1,750,000			0.71	%
	2015		1,100,000				0.89			1,100,000				0.89
	2016		750,000				0.85			750,000				0.85
	2017		1,250,000				0.86			1,250,000				0.86
			$	3,100,000			0.87	%		$	4,850,000			0.81	%
	(a)	For all interest rate derivatives, the Company receives discrete three-month LIBOR.
Interest Rate Swaps - Unsecured Debt Hedges	'
	Interest Rate Swaps – Unsecured Debt Hedges
	The Company had the following derivatives outstanding as of September 30, 2014 and December 31, 2013 that are used to effectively convert the variable interest rate on a portion of the Junior Subordinated Hybrid Securities ("Hybrid Securities") to a fixed rate.
	Maturity		Notional amount				Weighted average fixed rate paid by the Company (a)
	2036		$	25,000			4.28	%
	(a)	For all interest rate derivatives, the Company receives discrete three-month LIBOR.
Impact of Foreign Exchange Contracts on the Statement of Income	'
	Foreign Currency Exchange Risk
	In 2006, the Company issued €352.7 million of student loan asset-backed Euro Notes (the "Euro Notes") with an interest rate based on a spread to the EURIBOR index. As a result of the Euro Notes, the Company is exposed to market risk related to fluctuations in foreign currency exchange rates between the U.S. dollar and Euro. The principal and accrued interest on these notes are re-measured at each reporting period and recorded in the Company’s consolidated balance sheet in U.S. dollars based on the foreign currency exchange rate on that date.
	The Company entered into a cross-currency interest rate swap in connection with the issuance of the Euro Notes. Under the terms of the cross-currency interest rate swap, the Company receives from the counterparty a spread to the EURIBOR index based on a notional amount of €352.7 million and pays a spread to the LIBOR index based on a notional amount of $450.0 million. In addition, under the terms of this agreement, all principal payments on the Euro Notes will effectively be paid at the exchange rate in effect between the U.S. dollar and Euro as of the issuance of the notes.
	The following table shows the income statement impact as a result of the re-measurement of the Euro Notes and the change in the fair value of the related derivative instrument.
		Three months ended September 30,							Nine months ended September 30,
		2014				2013 (b)			2014			2013 (b)
	Re-measurement of Euro Notes	$	37,418			(39,974	)		39,216			(25,902	)
	Change in fair value of cross-currency interest rate swaps	(37,224		)		39,074			(40,261	)		18,978
	Total impact to consolidated statements of income - income (expense) (a)	$	194			(900	)		(1,045	)		(6,924	)
	(a)	The financial statement impact of the above items is included in "Derivative market value and foreign currency adjustments and derivative settlements, net" in the Company's consolidated statements of income.
	(b)	The 2013 operating results include the re-measurement of an additional €420.5 million of student loan asset-backed Euro notes and the change in fair value of a related cross-currency interest rate swap entered into in connection with the issuance of such notes. In November 2013, the principal amount outstanding on the notes was changed to U.S. dollars and the cross-currency interest swap was terminated.
	The re-measurement of the Euro-denominated bonds generally correlates with the change in fair value of the corresponding cross-currency interest rate swap. However, the Company will experience unrealized gains or losses related to the cross-currency interest rate swap if the two underlying indices (and related forward curve) do not move in parallel.
Schedule of Derivative Instruments in Statement of Financial Position, Fair Value	'
	Consolidated Financial Statement Impact Related to Derivatives
	The following table summarizes the fair value of the Company’s derivatives as reflected in the consolidated balance sheets:
		Fair value of asset derivatives							Fair value of liability derivatives
		As of				As of			As of			As of
		September 30,				December 31,			September 30,			December 31,
		2014				2013			2014			2013
	1:3 basis swaps	$	50,965			18,490			—			—
	Interest rate swaps - floor income hedges	8,804				7,183			6,297			15,849
	Interest rate swap option - floor income hedge	8,240				—			—			—
	Interest rate swaps - hybrid debt hedges	—				—			5,090			2,120
	Cross-currency interest rate swap	—				36,834			3,427			—
	Total	$	68,009			62,507			14,814			17,969
	During the nine months ended September 30, 2013, the Company terminated certain derivatives for gross proceeds and payments of $2.7 million and $9.2 million, respectively. There were no derivative terminations during the first nine months of 2014.
Schedule of Derivative Instruments [Table Text Block]	'
	Offsetting of Derivative Assets/Liabilities
	The Company records derivative instruments in the consolidated balance sheets on a gross basis as either an asset or liability measured at its fair value. Certain of the Company's derivative instruments are subject to right of offset provisions with counterparties. The following tables include the gross amounts related to the Company's derivative portfolio recognized in the consolidated balance sheets, reconciled to the net amount when excluding derivatives subject to enforceable master netting arrangements and cash collateral received/pledged:
							Gross amounts not offset in the consolidated balance sheets
	Derivative assets		Gross amounts of recognized assets presented in the consolidated balance sheets				Derivatives subject to enforceable master netting arrangement			Cash collateral received			Net asset (liability)
	Balance as of September 30, 2014		$	68,009			(11,387	)		—			56,622
	Balance as of December 31, 2013		62,507				(15,437	)		(15,959	)		31,111
							Gross amounts not offset in the consolidated balance sheets
	Derivative liabilities		Gross amounts of recognized liabilities presented in the consolidated balance sheets				Derivatives subject to enforceable master netting arrangement			Cash collateral pledged (received)			Net asset (liability)
	Balance as of September 30, 2014		$	(14,814	)		11,387			(22,422	)		(25,849	)
	Balance as of December 31, 2013		(17,969		)		15,437			3,630			1,098
Schedule of Derivative Instruments, Gain (Loss) in Statement of Financial Performance	'
	The following table summarizes the effect of derivative instruments in the consolidated statements of income.
		Three months ended September 30,							Nine months ended September 30,
		2014				2013			2014			2013
	Settlements:
	1:3 basis swaps	$	808			781			2,547			2,474
	Interest rate swaps - floor income hedges	(5,421		)		(7,178	)		(19,345	)		(24,017	)
	Interest rate swaps - hybrid debt hedges	(259		)		(256	)		(767	)		(1,413	)
	Cross-currency interest rate swaps	38				(35	)		288			(273	)
	Total settlements - expense	(4,834		)		(6,688	)		(17,277	)		(23,229	)
	Change in fair value:
	1:3 basis swaps	19,455				(2,161	)		32,475			9,402
	Interest rate swaps - floor income hedges	10,628				(9,599	)		11,173			33,231
	Interest rate swap option - floor income hedge	(847		)		—			(847	)		—
	Interest rate swaps - hybrid debt hedges	(393		)		2,700			(2,971	)		11,790
	Cross-currency interest rate swaps	(37,224		)		39,074			(40,261	)		18,978
	Other	—				—			—			342
	Total change in fair value - income (expense)	(8,381		)		30,014			(431	)		73,743
	Re-measurement of Euro Notes (foreign currency transaction adjustment) - income (expense)	37,418				(39,974	)		39,216			(25,902	)
	Derivative market value and foreign currency adjustments and derivative settlements, net - income (expense)	$	24,203			(16,648	)		21,508			24,612

Investments_Tables

Investments (Tables)	9 Months Ended
	Sep. 30, 2014
Investments [Abstract]	'
Summary Investment Holdings	'
	A summary of the Company's investments and restricted investments follows:
		As of September 30, 2014													As of December 31, 2013
		Amortized cost				Gross unrealized gains			Gross unrealized losses (a)			Fair value			Amortized cost	Gross unrealized gains	Gross unrealized losses		Fair value
	Investments:
	Available-for-sale investments:
	Student loan asset-backed and other debt securities (b)	$	123,898			6,309			(153	)		130,054			171,931	7,111	(1,241	)	177,801
	Equity securities	1,478				1,959			(21	)		3,416			1,502	1,783	(3	)	3,282
	Total available-for-sale investments	$	125,376			8,268			(174	)		133,470			173,433	8,894	(1,244	)	181,083
	Trading investments:
	Student loan asset-backed securities											5,370							10,957
	Equity securities											8,940							—
	Total trading investments											14,310							10,957
	Total available-for-sale and trading investments											$	147,780						192,040
	Restricted Investments (c):
	Guaranteed investment contracts - held-to-maturity											$	8,205						7,285
	(a)	As of September 30, 2014, the Company considered the decline in market value of its available-for-sale investments to be temporary in nature and did not consider any of its investments other-than-temporarily impaired.
	(b)	As of September 30, 2014, the stated maturities of the majority of the Company's student loan asset-backed and other debt securities classified as available-for-sale were greater than 10 years.
	(c)	Restricted investments are included in "restricted cash and investments" in the Company's consolidated balance sheets.
Realized Gain (Loss) on Investments [Table Text Block]	'
	The amounts reclassified from accumulated other comprehensive income related to the realized gains and losses on available-for-sale-securities is summarized below.
			Three months ended September 30,							Nine months ended September 30,
	Affected line item in the consolidated statements of income - income (expense):		2014				2013			2014			2013
	Other income		$	8			730			8,319			2,246
	Income tax expense		(3		)		(270	)		(3,078	)		(831	)
	Net		$	5			460			5,241			1,415

Business_Combination_Estimated

Business Combination Estimated Fair Value of Assets (Tables)	9 Months Ended
	Sep. 30, 2014
Business Combinations [Abstract]	'
Fair Value, by Balance Sheet Grouping [Table Text Block]	'
	The following table summarizes the estimated fair values of the assets acquired and liabilities assumed at the acquisition date.
	Cash and cash equivalents		$	326
	Accounts receivable		961
	Property and equipment		105
	Other assets		22
	Intangible assets		37,188
	Excess cost over fair value of net assets acquired (goodwill)		9,082
	Other liabilities		(1,341		)
	Net assets acquired		$	46,343
	The following table summarizes the fair values of all of the Company’s financial instruments on the consolidated balance sheets:
		As of September 30, 2014
		Fair value				Carrying value	Level 1	Level 2	Level 3
	Financial assets:
	Student loans receivable	$	29,975,188			28,701,344	—	—	29,975,188
	Cash and cash equivalents	74,579				74,579	74,579	—	—
	Investments	147,780				147,780	3,825	143,955	—
	Restricted cash	859,302				859,302	859,302	—	—
	Restricted cash – due to customers	72,836				72,836	72,836	—	—
	Restricted investments	8,205				8,205	8,205	—	—
	Accrued interest receivable	352,205				352,205	—	352,205	—
	Derivative instruments	68,009				68,009	—	68,009	—
	Financial liabilities:
	Bonds and notes payable	28,738,353				28,737,456	—	28,738,353	—
	Accrued interest payable	25,221				25,221	—	25,221	—
	Due to customers	72,836				72,836	72,836	—	—
	Derivative instruments	14,814				14,814	—	14,814	—
		As of December 31, 2013
		Fair value				Carrying value	Level 1	Level 2	Level 3
	Financial assets:
	Student loans receivable	$	26,641,383			25,907,589	—	—	26,641,383
	Cash and cash equivalents	63,267				63,267	63,267	—	—
	Investments	192,040				192,040	3,761	188,279	—
	Restricted cash	727,838				727,838	727,838	—	—
	Restricted cash – due to customers	167,576				167,576	167,576	—	—
	Restricted investments	7,285				7,285	7,285	—	—
	Accrued interest receivable	314,553				314,553	—	314,553	—
	Derivative instruments	62,507				62,507	—	62,507	—
	Financial liabilities:
	Bonds and notes payable	25,577,250				25,955,289	—	25,577,250	—
	Accrued interest payable	21,725				21,725	—	21,725	—
	Due to customers	167,576				167,576	167,576	—	—
	Derivative instruments	17,969				17,969	—	17,969	—

Intangible_Assets_Intangible_A1

Intangible Assets Intangible Assets (Tables)	9 Months Ended
	Sep. 30, 2014
Finite-Lived Intangible Assets, Net [Abstract]	'
Schedule of Finite-Lived Intangible Assets [Table Text Block]	'
	Intangible assets consist of the following:
		Weighted average remaining useful life as of September 30, 2014 (months)		As of September 30, 2014		As of December 31, 2013
	Amortizable intangible assets:
	Customer relationships (net of accumulated amortization of $22,866 and $19,821, respectively)	207		$	28,612	6,132
	Computer software (net of accumulated amortization of $1,210 and $0, respectively)	44		7,656		—
	Trade names (net of accumulated amortization of $156 and $0, respectively)	236		6,266		—
	Covenants not to compete (net of accumulated amortization of $12 and $0, respectively)	116		342		—
	Total - amortizable intangible assets	181		$	42,876	6,132
Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block]	'
	The Company recorded amortization expense on its intangible assets of $2.0 million and $0.8 million during the three months ended September 30, 2014 and 2013, respectively, and $4.4 million and $2.5 million during the nine months ended September 30, 2014 and 2013, respectively. The Company will continue to amortize intangible assets over their remaining useful lives. As of September 30, 2014 the Company estimates it will record amortization expense as follows:
	2014 (Q4)	$	1,984
	2015	8,695
	2016	5,349
	2017	3,862
	2018	3,533
	2019 and thereafter	19,453
		$	42,876

Goodwill_Goodwill_Tables

Goodwill Goodwill (Tables)	9 Months Ended
	Sep. 30, 2014
Goodwill and Intangible Assets Disclosure [Abstract]	'
Schedule of Goodwill [Table Text Block]	'
	The change in the carrying amount of goodwill by operating segment was as follows:
		Student Loan and Guaranty Servicing		Tuition Payment Processing and Campus Commerce	Enrollment Services	Asset Generation and Management	Total
	Balance as of December 31, 2013	$	8,596	58,086	8,553	41,883	117,118
	Goodwill acquired during the period	—		9,082	—	—	9,082
	Balance as of September 30, 2014	$	8,596	67,168	8,553	41,883	126,200

Earnings_per_Common_Share_Tabl

Earnings per Common Share (Tables)	9 Months Ended
	Sep. 30, 2014
Earnings Per Share [Abstract]	'
Schedule of Earnings Per Share, Basic and Diluted	'
		Three months ended September 30,
		2014				2013
		Common shareholders		Unvested restricted stock shareholders	Total	Common shareholders	Unvested restricted stock shareholders	Total
	Numerator:
	Net income attributable to Nelnet, Inc.	$	84,330	889	85,219	62,277	553	62,830
	Denominator:
	Weighted-average common shares outstanding - basic and diluted	45,948,255		484,425	46,432,680	46,086,743	409,869	46,496,612
	Earnings per share - basic and diluted	$	1.84	1.84	1.84	1.35	1.35	1.35
		Nine months ended September 30,
		2014				2013
		Common shareholders		Unvested restricted stock shareholders	Total	Common shareholders	Unvested restricted stock shareholders	Total
	Numerator:
	Net income attributable to Nelnet, Inc.	$	231,725	2,274	233,999	230,141	2,011	232,152
	Denominator:
	Weighted-average common shares outstanding - basic and diluted	46,044,429		451,880	46,496,309	46,189,200	404,041	46,593,241
	Earnings per share - basic and diluted	$	5.03	5.03	5.03	4.98	4.98	4.98

Segment_Reporting_Tables

Segment Reporting (Tables)	9 Months Ended
	Sep. 30, 2014
Segment Reporting [Abstract]	'
Schedule of Segment Reporting Information, by Segment	'
	See note 1 of the notes to consolidated financial statements included in the 2013 Annual Report for a description of the Company's operating segments. The following tables include the results of each of the Company's operating segments reconciled to the consolidated financial statements.
		Three months ended September 30, 2014
		Fee-Based
		Student Loan and Guaranty Servicing			Tuition Payment Processing and Campus Commerce		Enrollment		Total Fee-		Asset		Corporate		Eliminations		Total
							Services		Based		Generation and		Activity
											Management		and
													Overhead
	Total interest income	$	5		2		—		7		187,949		1,814		(346	)	189,424
	Interest expense	—			—		—		—		71,037		1,246		(346	)	71,937
	Net interest income	5			2		—		7		116,912		568		—		117,487
	Less provision for loan losses	—			—		—		—		2,000		—		—		2,000
	Net interest income after provision for loan losses	5			2		—		7		114,912		568		—		115,487
	Other income:
	Loan and guaranty servicing revenue	52,659			—		—		52,659		—		—		—		52,659
	Intersegment servicing revenue	13,432			—		—		13,432		—		—		(13,432	)	—
	Tuition payment processing and campus commerce revenue	—			26,399		—		26,399		—		—		—		26,399
	Enrollment services revenue	—			—		22,936		22,936		—		—		—		22,936
	Other income	—			—		—		—		4,294		3,356		—		7,650
	Gain on sale of loans and debt repurchases	—			—		—		—		—		—		—		—
	Derivative market value and foreign currency adjustments, net	—			—		—		—		29,430		(393	)	—		29,037
	Derivative settlements, net	—			—		—		—		(4,575	)	(259	)	—		(4,834	)
	Total other income	66,091			26,399		22,936		115,426		29,149		2,704		(13,432	)	133,847
	Operating expenses:
	Salaries and benefits	37,062			13,288		4,474		54,824		565		5,709		—		61,098
	Cost to provide enrollment services	—			—		14,178		14,178		—		—		—		14,178
	Depreciation and amortization	2,558			2,396		41		4,995		—		498		—		5,493
	Other	15,028			3,312		1,624		19,964		8,636		8,076		—		36,676
	Intersegment expenses, net	906			1,481		761		3,148		13,611		(3,327	)	(13,432	)	—
	Total operating expenses	55,554			20,477		21,078		97,109		22,812		10,956		(13,432	)	117,445
	Income (loss) before income taxes and corporate overhead allocation	10,542			5,924		1,858		18,324		121,249		(7,684	)	—		131,889
	Corporate overhead allocation	(2,567		)	(856	)	(855	)	(4,278	)	(1,026	)	5,304		—		—
	Income (loss) before income taxes	7,975			5,068		1,003		14,046		120,223		(2,380	)	—		131,889
	Income tax (expense) benefit	(3,030		)	(1,926	)	(381	)	(5,337	)	(45,684	)	4,508		—		(46,513	)
	Net income	4,945			3,142		622		8,709		74,539		2,128		—		85,376
	Net income attributable to noncontrolling interest	—			—		—		—		—		157		—		157
	Net income attributable to Nelnet, Inc.	$	4,945		3,142		622		8,709		74,539		1,971		—		85,219
		Three months ended September 30, 2013
		Fee-Based
		Student Loan and Guaranty Servicing			Tuition Payment Processing and Campus Commerce		Enrollment		Total Fee-		Asset		Corporate		Eliminations		Total
							Services		Based		Generation and		Activity
											Management		and
													Overhead
	Total interest income	$	10		—		—		10		158,793		2,201		(767	)	160,237
	Interest expense	—			—		—		—		56,100		(18	)	(767	)	55,315
	Net interest income	10			—		—		10		102,693		2,219		—		104,922
	Less provision for loan losses	—			—		—		—		5,000		—		—		5,000
	Net interest income after provision for loan losses	10			—		—		10		97,693		2,219		—		99,922
	Other income:
	Loan and guaranty servicing revenue	64,582			—		—		64,582		—		—		—		64,582
	Intersegment servicing revenue	13,519			—		—		13,519		—		—		(13,519	)	—
	Tuition payment processing and campus commerce revenue	—			19,927		—		19,927		—		—		—		19,927
	Enrollment services revenue	—			—		22,563		22,563		—		—		—		22,563
	Other income	—			—		—		—		3,981		4,632		—		8,613
	Gain on sale of loans and debt repurchases	—			—		—		—		2,138		—		—		2,138
	Derivative market value and foreign currency adjustments, net	—			—		—		—		(12,660	)	2,700		—		(9,960	)
	Derivative settlements, net	—			—		—		—		(6,432	)	(256	)	—		(6,688	)
	Total other income	78,101			19,927		22,563		120,591		(12,973	)	7,076		(13,519	)	101,175
	Operating expenses:
	Salaries and benefits	29,719			9,229		4,491		43,439		555		4,718		—		48,712
	Cost to provide enrollment services	—			—		14,668		14,668		—		—		—		14,668
	Depreciation and amortization	2,677			1,117		57		3,851		—		489		—		4,340
	Other	19,752			1,908		1,556		23,216		7,939		8,732		—		39,887
	Intersegment expenses, net	1,457			1,431		1,139		4,027		13,705		(4,213	)	(13,519	)	—
Total operating expenses	53,605			13,685		21,911		89,201		22,199		9,726		(13,519	)	107,607
Income (loss) before income taxes and corporate overhead allocation	24,506			6,242		652		31,400		62,521		(431	)	—		93,490
Corporate overhead allocation	(1,822		)	(607	)	(607	)	(3,036	)	(1,302	)	4,338		—		—
Income before income taxes	22,684			5,635		45		28,364		61,219		3,907		—		93,490
Income tax (expense) benefit	(8,620		)	(2,141	)	(17	)	(10,778	)	(23,263	)	3,597		—		(30,444	)
Net income	14,064			3,494		28		17,586		37,956		7,504		—		63,046
Net income attributable to noncontrolling interest	—			—		—		—		—		216		—		216
Net income attributable to Nelnet, Inc.	$	14,064		3,494		28		17,586		37,956		7,288		—		62,830
	Nine months ended September 30, 2014
	Fee-Based
	Student Loan and Guaranty Servicing			Tuition Payment Processing and Campus Commerce		Enrollment		Total Fee-		Asset		Corporate		Eliminations		Total
						Services		Based		Generation and		Activity
										Management		and
												Overhead
Total interest income	$	25		5		—		30		520,514		6,508		(1,805	)	525,247
Interest expense	—			—		—		—		198,449		4,532		(1,805	)	201,176
Net interest income	25			5		—		30		322,065		1,976		—		324,071
Less provision for loan losses	—			—		—		—		6,000		—		—		6,000
Net interest income after provision for loan losses	25			5		—		30		316,065		1,976		—		318,071
Other income:
Loan and guaranty servicing revenue	183,876			—		—		183,876		—		—		—		183,876
Intersegment servicing revenue	41,453			—		—		41,453		—		—		(41,453	)	—
Tuition payment processing and campus commerce revenue	—			73,468		—		73,468		—		—		—		73,468
Enrollment services revenue	—			—		65,092		65,092		—		—		—		65,092
Other income	—			—		—		—		12,954		28,142		—		41,096
Gain on sale of loans and debt repurchases	—			—		—		—		57		—		—		57
Derivative market value and foreign currency adjustments, net	—			—		—		—		41,755		(2,970	)	—		38,785
Derivative settlements, net	—			—		—		—		(16,510	)	(767	)	—		(17,277	)
Total other income	225,329			73,468		65,092		363,889		38,256		24,405		(41,453	)	385,097
Operating expenses:
Salaries and benefits	102,462			34,427		12,986		149,875		1,744		15,851		—		167,470
Cost to provide enrollment services	—			—		41,964		41,964		—		—		—		41,964
Depreciation and amortization	8,166			5,669		129		13,964		—		1,526		—		15,490
Other	53,295			8,915		4,917		67,127		24,627		20,926		—		112,680
Intersegment expenses, net	3,113			4,305		2,711		10,129		41,950		(10,626	)	(41,453	)	—
Total operating expenses	167,036			53,316		62,707		283,059		68,321		27,677		(41,453	)	337,604
Income (loss) before income taxes and corporate overhead allocation	58,318			20,157		2,385		80,860		286,000		(1,296	)	—		365,564
Corporate overhead allocation	(6,487		)	(2,163	)	(2,162	)	(10,812	)	(3,604	)	14,416		—		—
Income before income taxes	51,831			17,994		223		70,048		282,396		13,120		—		365,564
Income tax (expense) benefit	(19,695		)	(6,837	)	(85	)	(26,617	)	(107,309	)	3,724		—		(130,202	)
Net income	32,136			11,157		138		43,431		175,087		16,844		—		235,362
Net income attributable to noncontrolling interest	—			—		—		—		—		1,363		—		1,363
Net income attributable to Nelnet, Inc.	$	32,136		11,157		138		43,431		175,087		15,481		—		233,999
	Nine months ended September 30, 2013
	Fee-Based
	Student Loan and Guaranty Servicing			Tuition Payment Processing and Campus Commerce		Enrollment		Total Fee-		Asset		Corporate		Eliminations		Total
						Services		Based		Generation and		Activity
										Management		and
												Overhead
Total interest income	$	29		—		—		29		472,622		6,708		(2,420	)	476,939
Interest expense	—			—		—		—		170,502		3,718		(2,420	)	171,800
Net interest income	29			—		—		29		302,120		2,990		—		305,139
Less provision for loan losses	—			—		—		—		15,000		—		—		15,000
Net interest income after provision for loan losses	29			—		—		29		287,120		2,990		—		290,139
Other income:
Loan and guaranty servicing revenue	180,261			—		—		180,261		—		—		—		180,261
Intersegment servicing revenue	42,375			—		—		42,375		—		—		(42,375	)	—
Tuition payment processing and campus commerce revenue	—			61,694		—		61,694		—		—		—		61,694
Enrollment services revenue	—			—		76,343		76,343		—		—		—		76,343
Other income	—			—		—		—		11,207		19,110		—		30,317
Gain on sale of loans and debt repurchases	—			—		—		—		10,900		—		—		10,900
Derivative market value and foreign currency adjustments, net	—			—		—		—		35,711		12,130		—		47,841
Derivative settlements, net	—			—		—		—		(21,816	)	(1,413	)	—		(23,229	)
Total other income	222,636			61,694		76,343		360,673		36,002		29,827		(42,375	)	384,127
Operating expenses:
Salaries and benefits	86,254			28,015		15,067		129,336		1,709		13,004		—		144,049
Cost to provide enrollment services	—			—		51,097		51,097		—		—		—		51,097
Depreciation and amortization	8,197			3,387		179		11,763		—		1,274		—		13,037
Other	56,173			6,387		4,450		67,010		23,375		18,808		—		109,193
Intersegment expenses, net	3,243			4,350		3,418		11,011		42,955		(11,591	)	(42,375	)	—
Total operating expenses	153,867			42,139		74,211		270,217		68,039		21,495		(42,375	)	317,376
Income before income taxes and corporate overhead allocation	68,798			19,555		2,132		90,485		255,083		11,322		—		356,890
Corporate overhead allocation	(4,332		)	(1,443	)	(1,443	)	(7,218	)	(3,095	)	10,313		—		—
Income before income taxes	64,466			18,112		689		83,267		251,988		21,635		—		356,890
Income tax (expense) benefit	(24,498		)	(6,882	)	(261	)	(31,641	)	(95,755	)	3,759		—		(123,637	)
Net income	39,968			11,230		428		51,626		156,233		25,394		—		233,253
Net income attributable to noncontrolling interest	—			—		—		—		—		1,101		—		1,101
Net income attributable to Nelnet, Inc.	$	39,968		11,230		428		51,626		156,233		24,293		—		232,152

Fair_Value_Tables

Fair Value (Tables)	9 Months Ended
	Sep. 30, 2014
Fair Value Disclosures [Abstract]	'
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis	'
	The following tables present the Company’s financial assets and liabilities that are measured at fair value on a recurring basis. There were no transfers into or out of level 1, level 2, or level 3 for the nine months ended September 30, 2014.
		As of September 30, 2014						As of December 31, 2013
		Level 1				Level 2	Total	Level 1	Level 2	Total
	Assets:
	Investments:
	Student loan asset-backed securities	$	—			143,955	143,955	—	188,279	188,279
	Equity securities	3,416				—	3,416	3,282	—	3,282
	Debt securities	409				—	409	479	—	479
	Total investments	3,825				143,955	147,780	3,761	188,279	192,040
	Fair value of derivative instruments	—				68,009	68,009	—	62,507	62,507
	Total assets	$	3,825			211,964	215,789	3,761	250,786	254,547
	Liabilities:
	Fair value of derivative instruments	$	—			14,814	14,814	—	17,969	17,969
	Total liabilities	$	—			14,814	14,814	—	17,969	17,969
Fair Value, by Balance Sheet Grouping	'
	The following table summarizes the estimated fair values of the assets acquired and liabilities assumed at the acquisition date.
	Cash and cash equivalents		$	326
	Accounts receivable		961
	Property and equipment		105
	Other assets		22
	Intangible assets		37,188
	Excess cost over fair value of net assets acquired (goodwill)		9,082
	Other liabilities		(1,341		)
	Net assets acquired		$	46,343
	The following table summarizes the fair values of all of the Company’s financial instruments on the consolidated balance sheets:
		As of September 30, 2014
		Fair value				Carrying value	Level 1	Level 2	Level 3
	Financial assets:
	Student loans receivable	$	29,975,188			28,701,344	—	—	29,975,188
	Cash and cash equivalents	74,579				74,579	74,579	—	—
	Investments	147,780				147,780	3,825	143,955	—
	Restricted cash	859,302				859,302	859,302	—	—
	Restricted cash – due to customers	72,836				72,836	72,836	—	—
	Restricted investments	8,205				8,205	8,205	—	—
	Accrued interest receivable	352,205				352,205	—	352,205	—
	Derivative instruments	68,009				68,009	—	68,009	—
	Financial liabilities:
	Bonds and notes payable	28,738,353				28,737,456	—	28,738,353	—
	Accrued interest payable	25,221				25,221	—	25,221	—
	Due to customers	72,836				72,836	72,836	—	—
	Derivative instruments	14,814				14,814	—	14,814	—
		As of December 31, 2013
		Fair value				Carrying value	Level 1	Level 2	Level 3
	Financial assets:
	Student loans receivable	$	26,641,383			25,907,589	—	—	26,641,383
	Cash and cash equivalents	63,267				63,267	63,267	—	—
	Investments	192,040				192,040	3,761	188,279	—
	Restricted cash	727,838				727,838	727,838	—	—
	Restricted cash – due to customers	167,576				167,576	167,576	—	—
	Restricted investments	7,285				7,285	7,285	—	—
	Accrued interest receivable	314,553				314,553	—	314,553	—
	Derivative instruments	62,507				62,507	—	62,507	—
	Financial liabilities:
	Bonds and notes payable	25,577,250				25,955,289	—	25,577,250	—
	Accrued interest payable	21,725				21,725	—	21,725	—
	Due to customers	167,576				167,576	167,576	—	—
	Derivative instruments	17,969				17,969	—	17,969	—

Student_Loans_Receivable_Detai

Student Loans Receivable (Details) (USD $)	Sep. 30, 2014		Jun. 30, 2014	Dec. 31, 2013		Sep. 30, 2013	Jun. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'	'		'	'	'
Allowance for loan losses	$51,968		$52,467	$55,122		$54,197	$51,611	$51,902
Student loans receivable	28,701,344		'	25,907,589		'	'	'
Federally insured loans [Member]	'		'	'		'	'	'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'	'		'	'	'
Allowance for loan losses	39,470		'	'		42,406	'	'
Non-federally insured loans [Member]	'		'	'		'	'	'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'	'		'	'	'
Allowance for loan losses	12,498		'	'		11,791	'	'
held for investment [Member]	'		'	'		'	'	'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'	'		'	'	'
Student loans receivable, gross	28,929,222		'	26,121,306		'	'	'
Loan discount, net of unamortized loan premiums and deferred origination costs	175,910	[1]	'	158,595	[1]	'	'	'
Student loans receivable	28,701,344		'	25,907,589		'	'	'
held for investment [Member] | Federally insured loans [Member]	'		'	'		'	'	'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'	'		'	'	'
Student loans receivable, gross	28,851,599		'	26,050,203		'	'	'
Allowance for loan losses	39,470		'	43,440		'	'	'
held for investment [Member] | Non-federally insured loans [Member]	'		'	'		'	'	'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'	'		'	'	'
Student loans receivable, gross	77,623		'	71,103		'	'	'
Allowance for loan losses	12,498		'	11,682		'	'	'
held for investment [Member] | Stafford and Other [Member] | Federally insured loans [Member]	'		'	'		'	'	'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'	'		'	'	'
Student loans receivable, gross	6,218,910		'	6,686,626		'	'	'
held for investment [Member] | Consolidation Loans [Member] | Federally insured loans [Member]	'		'	'		'	'	'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'	'		'	'	'
Student loans receivable, gross	22,632,689		'	19,363,577		'	'	'
Non-accretable discount [Member] | held for investment [Member]	'		'	'		'	'	'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'	'		'	'	'
Student loans receivable, gross	8,400,000		'	4,400,000		'	'	'
Loan discount, net of unamortized loan premiums and deferred origination costs	$28,800		'	$20,200		'	'	'
[1]	For loans purchased where there is evidence of credit deterioration since the origination of the loan, the Company records a credit discount, separate from the allowance for loan losses, which is non-accretable to interest income. Remaining discounts and premiums for purchased loans are recognized in interest income over the remaining estimated lives of the loans. The Company continues to evaluate credit losses associated with purchased loans based on current information and changes in expectations to determine the need for any additional allowance for loan losses. As of SeptemberB 30, 2014 and DecemberB 31, 2013, "loan discount, net of unamortized loan premiums and deferred origination costs" included $28.8 million and $20.2 million, respectively, of non-accretable discount associated with purchased loans of $8.4 billion and $4.4 billion, respectively.

Student_Loans_Receivable_and_A2

Student Loans Receivable and Allowance for Loan Losses Residual Interests (Details) (USD $)	Sep. 30, 2014	Dec. 31, 2013	Sep. 30, 2014	Sep. 30, 2014	Dec. 31, 2013	Sep. 30, 2014
			Purchase of residual interest [Member]	Discount on bonds and notes payable [Member]	Discount on bonds and notes payable [Member]	Discount on bonds and notes payable [Member]
						Purchase of residual interest [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]	'	'	'	'	'	'
Financing Receivable, Significant Purchases	'	'	$2,600,000,000	'	'	'
Debt and Capital Lease Obligations	28,737,456,000	25,955,289,000	2,600,000,000	-407,301,000	-258,056,000	163,700,000
Unamortized Loan Commitment and Origination Fees and Unamortized Discounts or Premiums, Other	'	'	$68,700,000	'	'	'

Student_Loans_Receivable_and_A3

Student Loans Receivable and Allowance for Loan Losses Allowance for Loan Losses (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Financing Receivable, Allowance for Credit Losses [Roll Forward]	'	'	'	'
Allowance for loan losses - balance	$52,467	$51,611	$55,122	$51,902
Provision for loan losses	2,000	5,000	6,000	15,000
Charge-offs	-4,144	-4,048	-12,932	-14,742
Recoveries - non-federally insured loans	279	363	989	1,173
Purchase (sale) of federally insured loans and other, net	70	700	320	-1,243
Transfer from repurchase obligation related to non-federally insured loans purchased, net	1,296	571	2,469	2,107
Allowance for loan losses - balance	51,968	54,197	51,968	54,197
Federally insured loans [Member]	'	'	'	'
Financing Receivable, Allowance for Credit Losses [Roll Forward]	'	'	'	'
Provision for loan losses	2,000	5,000	7,000	16,000
Charge-offs	-3,521	-3,142	-11,290	-12,472
Allowance for loan losses - balance	39,470	42,406	39,470	42,406
Non-federally insured loans [Member]	'	'	'	'
Financing Receivable, Allowance for Credit Losses [Roll Forward]	'	'	'	'
Provision for loan losses	0	0	-1,000	-1,000
Charge-offs	-623	-906	-1,642	-2,270
Allowance for loan losses - balance	$12,498	$11,791	$12,498	$11,791

Student_Loans_Receivable_and_A4

Student Loans Receivable and Allowance for Loan Losses Repurchase Obligations (Details) (USD $)	3 Months Ended		9 Months Ended			9 Months Ended	12 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013	Sep. 30, 2014	Dec. 31, 2011	Sep. 30, 2014
						Cumulative non-federally insured loans participated subject to repurchase agreement [Member]	Non-federally insured loans sold subject to repurchase agreement [Member]	Non-federally insured loans sold subject to repurchase agreement [Member]
Repurchase Obligation [Line Items]	'	'	'	'	'	'	'	'
Cumulative amount of participated non-federally insured student loans	'	'	'	'	'	$103,600,000	'	'
Days delinquent to trigger repurchase range, minimum	'	'	'	'	'	'60 days	'	'
Days delinquent to trigger repurchase range, maximum	'	'	'	'	'	'90 days	'	'
Proceeds from sale of non-federally insured student loans subject to repurchase agreements	'	'	'	'	'	'	91,300,000	'
Percent of par value of non-federally insured student loans subject to repurchase agreements	'	'	'	'	'	'	100.00%	'
Days delinquent to trigger repurchase	'	'	'	'	'	'	'60 days	'
Change in Repurchase Obligation [Roll Forward]	'	'	'	'	'	'	'	'
Beginning balance	14,827,000	14,594,000	16,143,000	16,130,000	'	'	'	'
Transfer to the Allowance for Loan Losses Related to Loans Sold or Purchased and other, net	1,296,000	571,000	2,612,000	2,107,000	'	'	'	'
Ending balance	13,531,000	14,023,000	13,531,000	14,023,000	'	'	'	'
Student loans receivable	$28,701,344,000	'	$28,701,344,000	'	$25,907,589,000	'	'	$57,000,000

Student_Loans_Receivable_and_A5

Student Loans Receivable and Allowance for Loan Losses Student Loan Status and Delinquency (Details) (USD $)	Sep. 30, 2014	Dec. 31, 2013	Sep. 30, 2013
In Thousands, unless otherwise specified
Federally insured loans [Member]	'	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'	'
Loans in-school/grace/deferment	$3,072,318	$2,872,505	$3,039,819
Loans in forbearance	3,505,103	3,370,025	3,396,748
Student loans receivable, gross	28,851,599	26,050,203	24,792,577
Loans in repayment status:	'	'	'
Loans current	18,672,178	16,337,922	15,236,060
Loans current, percentage	83.80%	82.50%	83.10%
Loans delinquent 31-60 days	990,696	967,318	851,397
Loans delinquent 31-60 days, percentage	4.50%	4.90%	4.60%
Loans delinquent 61-90 days	569,879	550,333	480,285
Loans delinquent 61-90 days, percentage	2.60%	2.80%	2.60%
Loans delinquent 91-120 days	452,463	390,791	372,697
Loans delinquent 91-120 days, percentage	2.00%	2.00%	2.00%
Loans delinquent 121-270 days	1,183,616	1,117,936	978,234
Loans delinquent 121-270 days, percentage	5.30%	5.60%	5.30%
Loans Delinquent Greater than 271 Days	405,346	443,373	437,337
Loans delinquent 271 days or greater, percentage	1.80%	2.20%	2.40%
Total loans in repayment	$22,274,178	$19,807,673	$18,356,010
Total loans in repayment, percentage	100.00%	100.00%	100.00%
Non-federally insured loans [Member]	'	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'	'
Loans Delinquent 31 Days or Greater in Percentage	11.70%	12.70%	13.40%

Outstanding_Debt_Obligations_D

Outstanding Debt Obligations (Details) (USD $)	9 Months Ended	12 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
Debt Instrument [Line Items]	'	'
Bonds and notes payable	$28,737,456	$25,955,289
Variable-rate bonds and notes [Member]	'	'
Debt Instrument [Line Items]	'	'
Bonds and notes payable	28,197,754	24,614,143
Bonds and notes based on indices [Member]	'	'
Debt Instrument [Line Items]	'	'
Bonds and notes payable	26,639,879	23,479,893
Debt Instrument, Maturity Date Range, Start	25-May-18	25-May-18
Debt Instrument, Maturity Date Range, End	26-Aug-52	26-Aug-52
Debt Instrument, Interest Rate, Stated Percentage Rate Range, Minimum	0.24%	0.25%
Debt Instrument, Interest Rate, Stated Percentage Rate Range, Maximum	6.90%	6.90%
Bonds and notes based on auction or remarketing [Member]	'	'
Debt Instrument [Line Items]	'	'
Bonds and notes payable	1,557,875	1,134,250
Debt Instrument, Maturity Date Range, Start	1-May-28	1-May-28
Debt Instrument, Maturity Date Range, End	26-Nov-46	26-Nov-46
Debt Instrument, Interest Rate, Stated Percentage Rate Range, Minimum	0.07%	0.07%
Debt Instrument, Interest Rate, Stated Percentage Rate Range, Maximum	2.11%	2.17%
FFELP warehouse facilities [Member]	'	'
Debt Instrument [Line Items]	'	'
Bonds and notes payable	787,042	1,396,344
Debt Instrument, Maturity Date Range, Start	17-Jan-16	17-Jan-16
Debt Instrument, Maturity Date Range, End	11-Jun-17	12-Jun-16
Debt Instrument, Interest Rate, Stated Percentage Rate Range, Minimum	0.16%	0.17%
Debt Instrument, Interest Rate, Stated Percentage Rate Range, Maximum	0.25%	0.25%
Line of Credit [Member]	'	'
Debt Instrument [Line Items]	'	'
Bonds and notes payable	0	45,000
Debt Instrument, Maturity Date Range, Start	30-Jun-19	28-Mar-18
Debt Instrument, Maturity Date Range, End	30-Jun-19	28-Mar-18
Debt Instrument, Interest Rate, Stated Percentage Rate Range, Minimum	0.00%	1.67%
Debt Instrument, Interest Rate, Stated Percentage Rate Range, Maximum	0.00%	1.67%
Junior Subordinated Debt [Member]	'	'
Debt Instrument [Line Items]	'	'
Bonds and notes payable	96,457	96,457
Debt Instrument, Maturity Date Range, Start	15-Sep-61	15-Sep-61
Debt Instrument, Maturity Date Range, End	15-Sep-61	15-Sep-61
Debt Instrument, Interest Rate, Stated Percentage Rate Range, Minimum	3.61%	3.62%
Debt Instrument, Interest Rate, Stated Percentage Rate Range, Maximum	3.61%	3.62%
Other borrowings [Member]	'	'
Debt Instrument [Line Items]	'	'
Bonds and notes payable	63,504	61,401
Debt Instrument, Maturity Date Range, Start	14-Nov-14	11-Apr-14
Debt Instrument, Maturity Date Range, End	31-Dec-18	11-Nov-15
Debt Instrument, Interest Rate, Stated Percentage Rate Range, Minimum	1.66%	1.67%
Debt Instrument, Interest Rate, Stated Percentage Rate Range, Maximum	5.10%	5.10%
Bonds and notes payable, gross [Member]	'	'
Debt Instrument [Line Items]	'	'
Bonds and notes payable	29,144,757	26,213,345
Discount on bonds and notes payable [Member]	'	'
Debt Instrument [Line Items]	'	'
Bonds and notes payable	($407,301)	($258,056)

Bonds_and_Notes_Payable_Outsta

Bonds and Notes Payable Outstanding Lines of Credit (Details) (USD $)	3 Months Ended						9 Months Ended		9 Months Ended
	Sep. 30, 2014		Sep. 30, 2014		Sep. 30, 2014	Sep. 30, 2014	Sep. 30, 2014	Jun. 30, 2014	Sep. 30, 2014	Oct. 31, 2014
	NHELP-II Warehouse [Member]		NFSLW-I Warehouse [Member]		NHELP-III Warehouse [Member]	FFELP Warehouse Total [Member]	Line of Credit [Member]	Line of Credit [Member]	Secured line of credit [Member]	Secured line of credit [Member]
Line of Credit Facility [Line Items]	'		'		'	'	'	'	'	'
Maximum financing amount	$500,000,000	[1]	$500,000,000	[2]	$750,000,000	$1,750,000,000	$350,000,000	$275,000,000	$50,000,000	$75,000,000
Amount outstanding	40,433,000	[1]	308,344,000	[2]	438,265,000	787,042,000	0	'	'	'
Amount available	459,567,000	[1]	191,656,000	[2]	311,735,000	962,958,000	350,000,000	'	'	'
Expiration of liquidity provisions	17-Dec-14	[1]	11-Jun-15	[2]	5-Feb-15	'	'	'	'	'
Debt Instrument, Maturity Date Range, End	17-Dec-16	[1]	11-Jun-17	[2]	17-Jan-16	'	'	'	'	'
Line of credit facility, termination date	'		'		'	'	30-Jun-19	'	'	'
Maximum Advance Rates - range minimum	84.50%	[1]	92.00%	[2]	92.15%	'	'	'	'	'
Maximum advance rates - range maximum	94.50%	[1]	98.00%	[2]	95.00%	'	'	'	'	'
Minimum Advance Rates - range minimum	84.50%	[1]	84.00%	[2]	92.15%	'	'	'	'	'
Minimum advance rates - range maximum	94.50%	[1]	90.00%	[2]	95.00%	'	'	'	'	'
Advanced as equity support	$4,195,000	[1]	$14,778,000	[2]	$26,264,000	$45,237,000	'	'	'	'
Line of Credit Facility, Expiration Date	'		'		'	'	'	'	31-Oct-16	'
[1]	On September 30, 2014, the Company amended the agreement for this warehouse facility to change the expiration date for the liquidity provisions to December 17, 2014, and change the maturity date to December 17, 2016.
[2]	On April 15, 2014, the Company amended the agreement for this warehouse facility to change the expiration date for the liquidity provisions to JuneB 11, 2015, and change the maturity date to JuneB 11, 2017.

Bonds_and_Notes_Payable_Assetb

Bonds and Notes Payable Asset-backed Securitizations (Details) (USD $)	9 Months Ended
	Sep. 30, 2014
Debt Instrument [Line Items]	'
Debt Instrument, Variable Rate Basis	'1-month LIBOR
Asset-backed securitization issuance, Face Amount	$3,239,800,000
2014-6 Securitization [Member]	'
Debt Instrument [Line Items]	'
Asset-backed securitization, issuance date	31-Jul-14	[1]
Asset-backed securitization issuance, Face Amount	565,000,000	[1]
2014-1 Securitization [Member]	'
Debt Instrument [Line Items]	'
Asset-backed securitization, issuance date	6-Feb-14
Asset-backed securitization issuance, Face Amount	458,500,000
2014-2 Securitization [Member]	'
Debt Instrument [Line Items]	'
Asset-backed securitization, issuance date	12-Mar-14
Asset-backed securitization issuance, Face Amount	509,000,000
2014-2 Securitization [Member] | 2014-2 Securitization Class A-1 [Member]	'
Debt Instrument [Line Items]	'
Asset-backed securitization, issuance date	12-Mar-14
2014-2 Securitization [Member] | 2014-2 Securitization Class A-2 [Member]	'
Debt Instrument [Line Items]	'
Asset-backed securitization, issuance date	12-Mar-14
2014-2 Securitization [Member] | 2014-2 Securitization Class A-3 [Member]	'
Debt Instrument [Line Items]	'
Asset-backed securitization, issuance date	12-Mar-14
2014-3 Securitization [Member]	'
Debt Instrument [Line Items]	'
Asset-backed securitization, issuance date	30-Apr-14
Asset-backed securitization issuance, Face Amount	719,800,000
2014-4 Securitization [Member] [Domain]	'
Debt Instrument [Line Items]	'
Asset-backed securitization, issuance date	23-May-14
Asset-backed securitization issuance, Face Amount	384,500,000
2014-4 Securitization [Member] [Domain] | 2014-4 Securitization Class A-1 [Member]	'
Debt Instrument [Line Items]	'
Asset-backed securitization, issuance date	23-May-14
2014-4 Securitization [Member] [Domain] | 2014-4 Securitization Class A-2 [Member]	'
Debt Instrument [Line Items]	'
Asset-backed securitization, issuance date	23-May-14
2014-5 Securitization [Member] [Domain]	'
Debt Instrument [Line Items]	'
Asset-backed securitization, issuance date	18-Jun-14
Asset-backed securitization issuance, Face Amount	603,000,000
Class A [Member]	'
Debt Instrument [Line Items]	'
Asset-backed securitization issuance, Unamortized Discount	-3,659,000
Asset-backed securitization issuance, Face Amount	3,169,700,000
Long-term Debt, Fair Value	3,166,041,000
Class A [Member] | 2014-6 Securitization [Member]	'
Debt Instrument [Line Items]	'
Debt Instrument, Basis Spread on Variable Rate Basis	0.65%	[1]
Asset-backed securitization issuance, Unamortized Discount	-3,124,000	[1]
Asset-backed securitization issuance, Face Amount	565,000,000	[1]
Long-term Debt, Fair Value	561,876,000	[1]
Debt Instrument, Maturity Date Range, End	25-Nov-47	[1]
Class A [Member] | 2014-1 Securitization [Member]	'
Debt Instrument [Line Items]	'
Debt Instrument, Basis Spread on Variable Rate Basis	0.57%
Asset-backed securitization issuance, Unamortized Discount	0
Asset-backed securitization issuance, Face Amount	445,000,000
Long-term Debt, Fair Value	445,000,000
Debt Instrument, Maturity Date Range, End	25-Sep-41
Class A [Member] | 2014-2 Securitization [Member]	'
Debt Instrument [Line Items]	'
Asset-backed securitization issuance, Unamortized Discount	-535,000
Asset-backed securitization issuance, Face Amount	497,000,000
Long-term Debt, Fair Value	496,465,000
Class A [Member] | 2014-2 Securitization [Member] | 2014-2 Securitization Class A-1 [Member]	'
Debt Instrument [Line Items]	'
Debt Instrument, Basis Spread on Variable Rate Basis	0.28%
Asset-backed securitization issuance, Unamortized Discount	0
Asset-backed securitization issuance, Face Amount	191,000,000
Long-term Debt, Fair Value	191,000,000
Debt Instrument, Maturity Date Range, End	25-Jun-21
Class A [Member] | 2014-2 Securitization [Member] | 2014-2 Securitization Class A-2 [Member]	'
Debt Instrument [Line Items]	'
Debt Instrument, Basis Spread on Variable Rate Basis	0.60%
Asset-backed securitization issuance, Unamortized Discount	0
Asset-backed securitization issuance, Face Amount	222,000,000
Long-term Debt, Fair Value	222,000,000
Debt Instrument, Maturity Date Range, End	25-Mar-30
Class A [Member] | 2014-2 Securitization [Member] | 2014-2 Securitization Class A-3 [Member]	'
Debt Instrument [Line Items]	'
Debt Instrument, Basis Spread on Variable Rate Basis	0.85%
Asset-backed securitization issuance, Unamortized Discount	-535,000
Asset-backed securitization issuance, Face Amount	84,000,000
Long-term Debt, Fair Value	83,465,000
Debt Instrument, Maturity Date Range, End	27-Jul-37
Class A [Member] | 2014-3 Securitization [Member]	'
Debt Instrument [Line Items]	'
Debt Instrument, Basis Spread on Variable Rate Basis	0.58%
Asset-backed securitization issuance, Unamortized Discount	0
Asset-backed securitization issuance, Face Amount	700,700,000
Long-term Debt, Fair Value	700,700,000
Debt Instrument, Maturity Date Range, End	25-Jun-41
Class A [Member] | 2014-4 Securitization [Member] [Domain]	'
Debt Instrument [Line Items]	'
Asset-backed securitization issuance, Unamortized Discount	0
Asset-backed securitization issuance, Face Amount	375,000,000
Long-term Debt, Fair Value	375,000,000
Class A [Member] | 2014-4 Securitization [Member] [Domain] | 2014-4 Securitization Class A-1 [Member]	'
Debt Instrument [Line Items]	'
Debt Instrument, Basis Spread on Variable Rate Basis	0.54%
Asset-backed securitization issuance, Unamortized Discount	0
Asset-backed securitization issuance, Face Amount	267,500,000
Long-term Debt, Fair Value	267,500,000
Debt Instrument, Maturity Date Range, End	27-Nov-34
Class A [Member] | 2014-4 Securitization [Member] [Domain] | 2014-4 Securitization Class A-2 [Member]	'
Debt Instrument [Line Items]	'
Debt Instrument, Basis Spread on Variable Rate Basis	0.95%
Asset-backed securitization issuance, Unamortized Discount	0
Asset-backed securitization issuance, Face Amount	107,500,000
Long-term Debt, Fair Value	107,500,000
Debt Instrument, Maturity Date Range, End	25-Nov-43
Class A [Member] | 2014-5 Securitization [Member] [Domain]	'
Debt Instrument [Line Items]	'
Debt Instrument, Basis Spread on Variable Rate Basis	0.55%
Asset-backed securitization issuance, Unamortized Discount	0
Asset-backed securitization issuance, Face Amount	587,000,000
Long-term Debt, Fair Value	587,000,000
Debt Instrument, Maturity Date Range, End	25-Jul-41
Class B [Member]	'
Debt Instrument [Line Items]	'
Asset-backed securitization issuance, Unamortized Discount	-6,015,000
Asset-backed securitization issuance, Face Amount	70,100,000
Long-term Debt, Fair Value	64,085,000
Fair Value Disclosure, Off-balance Sheet Risks, Face Amount, Asset	64,600,000
Class B [Member] | 2014-6 Securitization [Member]	'
Debt Instrument [Line Items]	'
Fair Value Disclosure, Off-balance Sheet Risks, Amount, Asset	8,300,000
Class B [Member] | 2014-1 Securitization [Member]	'
Debt Instrument [Line Items]	'
Debt Instrument, Basis Spread on Variable Rate Basis	1.50%
Asset-backed securitization issuance, Unamortized Discount	-1,132,000
Asset-backed securitization issuance, Face Amount	13,500,000
Long-term Debt, Fair Value	12,368,000
Debt Instrument, Maturity Date Range, End	25-Oct-47
Class B [Member] | 2014-2 Securitization [Member]	'
Debt Instrument [Line Items]	'
Debt Instrument, Basis Spread on Variable Rate Basis	1.50%
Asset-backed securitization issuance, Unamortized Discount	-1,046,000
Asset-backed securitization issuance, Face Amount	12,000,000
Long-term Debt, Fair Value	10,954,000
Debt Instrument, Maturity Date Range, End	25-Jun-41
Class B [Member] | 2014-3 Securitization [Member]	'
Debt Instrument [Line Items]	'
Debt Instrument, Basis Spread on Variable Rate Basis	1.50%
Asset-backed securitization issuance, Unamortized Discount	-1,467,000
Asset-backed securitization issuance, Face Amount	19,100,000
Long-term Debt, Fair Value	17,633,000
Debt Instrument, Maturity Date Range, End	25-Oct-50
Class B [Member] | 2014-4 Securitization [Member] [Domain]	'
Debt Instrument [Line Items]	'
Debt Instrument, Basis Spread on Variable Rate Basis	1.50%
Asset-backed securitization issuance, Unamortized Discount	-1,138,000
Asset-backed securitization issuance, Face Amount	9,500,000
Long-term Debt, Fair Value	8,362,000
Debt Instrument, Maturity Date Range, End	25-Sep-51
Class B [Member] | 2014-5 Securitization [Member] [Domain]	'
Debt Instrument [Line Items]	'
Debt Instrument, Basis Spread on Variable Rate Basis	1.50%
Asset-backed securitization issuance, Unamortized Discount	-1,232,000
Asset-backed securitization issuance, Face Amount	16,000,000
Long-term Debt, Fair Value	$14,768,000
Debt Instrument, Maturity Date Range, End	25-May-49
[1]	Total original principal amount excludes the Class B subordinated notes of $8.3 million that were retained at issuance. As of September 30, 2014, the Company has a total of $64.6 million (par value) of its own Class B subordinated notes remaining from prior completed asset-backed securitizations that are not included in the Company's consolidated balance sheet. If the Company sells these notes to third parties, the Company would obtain cash proceeds equal to the market value of the notes on the date of such sale. Upon sale, these notes would be shown as bbonds and notes payableb in the Company's consolidated balance sheet. The Company believes the market value of such notes is currently less than par value. Any excess of the par value over the market value on the date of sale would be recognized by the Company as interest expense over the life of the bonds.

Bonds_and_Notes_Payable_Debt_R

Bonds and Notes Payable Debt Repurchases (Details) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Debt Instrument [Line Items]	'	'	'	'
Gain from debt repurchases	'	'	$57,000	$10,866,000
Asset-backed Securities [Member]	'	'	'	'
Debt Instrument [Line Items]	'	'	'	'
Extinguishment of Debt, Amount	2,500,000	15,400,000	4,000,000	84,700,000
Gain from debt repurchases	$0	$2,100,000	$57,000	$10,900,000

Derivative_Financial_Instrumen2

Derivative Financial Instruments Outstanding (Details) (USD $)

9 Months Ended

9 Months Ended

12 Months Ended

9 Months Ended

12 Months Ended

9 Months Ended

12 Months Ended

3 Months Ended

9 Months Ended

12 Months Ended

In Thousands, unless otherwise specified

Sep. 30, 2014

Sep. 30, 2013

Dec. 31, 2013

Sep. 30, 2014

Dec. 31, 2013

Sep. 30, 2014

Dec. 31, 2013

Sep. 30, 2014

Dec. 31, 2013

Sep. 30, 2014

Dec. 31, 2013

Sep. 30, 2014

Dec. 31, 2013

Sep. 30, 2014

Dec. 31, 2013

Sep. 30, 2014

Dec. 31, 2013

Sep. 30, 2014

Dec. 31, 2013

Sep. 30, 2014

Dec. 31, 2013

Sep. 30, 2014

Dec. 31, 2013

Sep. 30, 2014

Dec. 31, 2013

Sep. 30, 2014

Dec. 31, 2013

Sep. 30, 2014

Dec. 31, 2013

Sep. 30, 2014

Dec. 31, 2013

Sep. 30, 2014

Dec. 31, 2013

Sep. 30, 2014

Dec. 31, 2013

Sep. 30, 2014

Sep. 30, 2014

Dec. 31, 2013

1:3 basis swaps [Member]

1:3 basis swaps [Member]

1:3 basis swaps [Member]

1:3 basis swaps [Member]

1:3 basis swaps [Member]

1:3 basis swaps [Member]

1:3 basis swaps [Member]

1:3 basis swaps [Member]

1:3 basis swaps [Member]

1:3 basis swaps [Member]

1:3 basis swaps [Member]

1:3 basis swaps [Member]

1:3 basis swaps [Member]

1:3 basis swaps [Member]

1:3 basis swaps [Member]

1:3 basis swaps [Member]

1:3 basis swaps [Member]

1:3 basis swaps [Member]

1:3 basis swaps [Member]

1:3 basis swaps [Member]

Fixed Rate Floor Income Interest Rate Swap [Member]

Fixed Rate Floor Income Interest Rate Swap [Member]

Fixed Rate Floor Income Interest Rate Swap [Member]

Fixed Rate Floor Income Interest Rate Swap [Member]

Fixed Rate Floor Income Interest Rate Swap [Member]

Fixed Rate Floor Income Interest Rate Swap [Member]

Fixed Rate Floor Income Interest Rate Swap [Member]

Fixed Rate Floor Income Interest Rate Swap [Member]

Fixed Rate Floor Income Interest Rate Swap [Member]

Fixed Rate Floor Income Interest Rate Swap [Member]

Unsecured Debt Interest Rate Swaps 1 [Member]

Unsecured Debt Interest Rate Swaps 1 [Member]

Interest rate swap option - floor income hedges [Member]

Interest rate swap option - floor income hedges [Member]

Interest rate swap option - floor income hedges [Member]

Maturity 2021 [Member]

Maturity 2021 [Member]

Maturity 2022 [Member]

Maturity 2022 [Member]

Maturity 2023 [Member]

Maturity 2023 [Member]

Maturity 2024 [Member]

Maturity 2024 [Member]

Maturity 2026 [Member]

Maturity 2026 [Member]

Maturity 2028 [Member]

Maturity 2028 [Member]

Maturity 2036 [Member]

Maturity 2036 [Member]

Maturity 2039 [Member]

Maturity 2039 [Member]

Maturity 2040 [Member]

Maturity 2040 [Member]

Maturity 2014 [Member]

Maturity 2014 [Member]

Maturity 2015 [Member]

Maturity 2015 [Member]

Maturity 2016 [Member]

Maturity 2016 [Member]

Maturity 2017 [Member]

Maturity 2017 [Member]

Maturity 2036 [Member]

Maturity 2036 [Member]

Derivative [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Increase (Decrease) in Financial Instruments Used in Operating Activities

$9,087

$0

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

$9,100

'

'

Derivative, Type of Interest Rate Paid on Swap

'

'

'

'one-month LIBOR

'one-month LIBOR

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Weighted average basis spread on variable rate paid on swap

'

'

'

3.50%

3.50%

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Derivative, Notional Amount

'

'

'

8,000,000

[1]

8,000,000

[1]

250,000

250,000

1,900,000

1,900,000

3,650,000

3,650,000

250,000

250,000

800,000

800,000

100,000

100,000

700,000

700,000

150,000

[2]

150,000

200,000

[3]

200,000

3,100,000

4,850,000

0

1,750,000

1,100,000

1,100,000

750,000

750,000

1,250,000

1,250,000

25,000

25,000

250,000

250,000

'

Derivative, Average Fixed Interest Rate

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

0.87%

[4]

0.81%

[4]

0.00%

[4]

0.71%

[4]

0.89%

[4]

0.89%

[4]

0.85%

[4]

0.85%

[4]

0.86%

[4]

0.86%

[4]

4.28%

[4]

4.28%

'

'

'

Bonds and notes payable

$28,737,456

'

$25,955,289

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Derivative, Type of Interest Rate Received on Swap

'

'

'

'3-month LIBOR

'3-month LIBOR

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'3-month LIBOR

'3-month LIBOR

'

'

'

'

'

'

'

'

'3-month LIBOR

'3-month LIBOR

'

'1-month LIBOR

'1-month LIBOR

Derivative, Swaption Interest Rate

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

3.30%

3.30%

'

[1]

The weighted average rate paid by the Company on the 1:3 Basis Swaps as of SeptemberB 30, 2014 and DecemberB 31, 2013 was one-month LIBOR plus 3.5 basis points

[2]

This derivative has a forward effective start date in 2015.

[3]

This derivative has a forward effective start date in 2020.

[4]

For all interest rate derivatives, the Company receives discrete three-month LIBOR.

Derivative_Financial_Instrumen3

Derivative Financial Instruments Cross-currency Interest Rate Swaps (Details)

3 Months Ended

9 Months Ended

3 Months Ended

9 Months Ended

In Thousands, unless otherwise specified

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Dec. 31, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2014

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

Currency Swap [Member]

Currency Swap [Member]

Currency Swap [Member]

Currency Swap [Member]

Cross-currency interest rate swap 1 [Member]

Cross currency interest rate swap 2 [Member]

Cross currency interest rate swap 2 [Member]

USD ($)

USD ($)

USD ($)

USD ($)

EUR (€)

USD ($)

EUR (€)

Derivative Instruments, Gain (Loss) [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

Bonds and notes payable

$28,737,456

'

$28,737,456

'

$25,955,289

'

'

'

'

€ 420,500

'

€ 352,700

Derivative, Notional Amount

'

'

'

'

'

'

'

'

'

'

450,000

352,700

Re-measurement of Euro Notes

37,418

-39,974

39,216

-25,902

'

37,418

-39,974

[1]

39,216

-25,902

[1]

'

'

'

Change in fair value of cross currency interest rate swaps

'

'

'

'

'

-37,224

39,074

[1]

-40,261

18,978

[1]

'

'

'

Total impact to statements of income - income (expense)

($8,381)

$30,014

($431)

$73,743

'

$194

[2]

($900)

[1],[2]

($1,045)

[2]

($6,924)

[1],[2]

'

'

'

[1]

The 2013 operating results include the re-measurement of an additional €420.5 million of student loan asset-backed Euro notes and the change in fair value of a related cross-currency interest rate swap entered into in connection with the issuance of such notes. In November 2013, the principal amount outstanding on the notes was changed to U.S. dollars and the cross-currency interest swap was terminated.

[2]

The financial statement impact of the above items is included in "Derivative market value and foreign currency adjustments and derivative settlements, net" in the Company's consolidated statements of income.

Derivative_Financial_Instrumen4

Derivative Financial Instruments Fair Value of Derivative Instruments (Details) (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013
Derivatives, Fair Value [Line Items]	'	'	'
Fair value of derivative instruments, asset	$68,009	'	$62,507
Fair value of derivative instruments, liability	14,814	'	17,969
Proceeds to terminate and or amend derivative instruments	0	2,700	'
Payments to terminate and/or amend derivative instruments	0	9,200	'
1:3 basis swaps [Member]	'	'	'
Derivatives, Fair Value [Line Items]	'	'	'
Fair value of derivative instruments, asset	50,965	'	18,490
Fair value of derivative instruments, liability	0	'	0
Interest rate swaps - floor income hedges [Member]	'	'	'
Derivatives, Fair Value [Line Items]	'	'	'
Fair value of derivative instruments, asset	8,804	'	7,183
Fair value of derivative instruments, liability	6,297	'	15,849
Interest rate swap option - floor income hedges [Member]	'	'	'
Derivatives, Fair Value [Line Items]	'	'	'
Fair value of derivative instruments, asset	8,240	'	0
Fair value of derivative instruments, liability	0	'	0
Interest rate swaps - hybrid debt hedges [Member]	'	'	'
Derivatives, Fair Value [Line Items]	'	'	'
Fair value of derivative instruments, asset	0	'	0
Fair value of derivative instruments, liability	5,090	'	2,120
Cross-currency interest rate swaps [Member]	'	'	'
Derivatives, Fair Value [Line Items]	'	'	'
Fair value of derivative instruments, asset	0	'	36,834
Fair value of derivative instruments, liability	$3,427	'	$0

Derivative_Financial_Instrumen5

Derivative Financial Instruments Gross/Net (Details) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Derivatives, Fair Value [Line Items]	'	'
Fair value of derivative instruments, asset	($68,009)	($62,507)
Fair value of derivative instruments, liability	-14,814	-17,969
Derivatives subject to enforceable master netting arrangement, asset	-11,387	-15,437
Derivatives subject to enforceable master netting arrangement, liability	11,387	15,437
Cash collateral received	0	-15,959
Cash collateral pledged	-22,422	3,630
Fair value of derivative instruments, asset, net	56,622	31,111
Fair value of derivative instruments, liability, net	$25,849	($1,098)

Derivative_Financial_Instrumen6

Derivative Financial Instruments Income Statement Effect of Derivative Instruments (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Derivative Instruments, Gain (Loss) [Line Items]	'	'	'	'
Derivative settlements, net	($4,834)	($6,688)	($17,277)	($23,229)
Change in fair value	-8,381	30,014	-431	73,743
Re-measurement of Euro Notes (foreign currency transaction adjustment) - income (expense)	37,418	-39,974	39,216	-25,902
Derivative market value and foreign currency adjustments and derivative settlements - income (expense)	24,203	-16,648	21,508	24,612
1:3 basis swaps [Member]	'	'	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'	'	'
Derivative settlements, net	808	781	2,547	2,474
Change in fair value	19,455	-2,161	32,475	9,402
Interest rate swaps - floor income hedges [Member]	'	'	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'	'	'
Derivative settlements, net	-5,421	-7,178	-19,345	-24,017
Change in fair value	10,628	-9,599	11,173	33,231
Interest rate swap option - floor income hedges [Member]	'	'	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'	'	'
Change in fair value	-847	0	-847	0
Interest rate swaps - hybrid debt hedges [Member]	'	'	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'	'	'
Derivative settlements, net	-259	-256	-767	-1,413
Change in fair value	-393	2,700	-2,971	11,790
Cross-currency interest rate swaps [Member]	'	'	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'	'	'
Derivative settlements, net	38	-35	288	-273
Change in fair value	-37,224	39,074	-40,261	18,978
Other [Member]	'	'	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'	'	'
Change in fair value	$0	$0	$0	$342

Investments_and_Restricted_Inv

Investments and Restricted Investments Summary (Details) (USD $)	9 Months Ended		12 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014		Dec. 31, 2013
Investments [Member]	'		'
Investment Holdings [Line Items]	'		'
Investments, Fair Value Disclosure	$147,780		$192,040
Investments [Member] | Available-for-sale investments [Member]	'		'
Investment Holdings [Line Items]	'		'
Amortized cost	125,376		173,433
Gross unrealized gains	8,268		8,894
Gross unrealized losses	-174	[1]	-1,244
Investments, Fair Value Disclosure	133,470		181,083
Investments [Member] | Available-for-sale investments [Member] | Student Loan Asset-Backed and Other Debt Securities [Member]	'		'
Investment Holdings [Line Items]	'		'
Amortized cost	123,898	[2]	171,931	[2]
Gross unrealized gains	6,309	[2]	7,111	[2]
Gross unrealized losses	-153	[1],[2]	-1,241	[2]
Investments, Fair Value Disclosure	130,054	[2]	177,801	[2]
Investments [Member] | Available-for-sale investments [Member] | Equity securities [Member]	'		'
Investment Holdings [Line Items]	'		'
Amortized cost	1,478		1,502
Gross unrealized gains	1,959		1,783
Gross unrealized losses	-21	[1]	-3
Investments, Fair Value Disclosure	3,416		3,282
Investments [Member] | Trading investments [Member]	'		'
Investment Holdings [Line Items]	'		'
Investments, Fair Value Disclosure	14,310		10,957
Investments [Member] | Trading investments [Member] | Student Loan Asset-Backed and Other Debt Securities [Member]	'		'
Investment Holdings [Line Items]	'		'
Investments, Fair Value Disclosure	5,370		10,957
Investments [Member] | Trading investments [Member] | Equity securities [Member]	'		'
Investment Holdings [Line Items]	'		'
Investments, Fair Value Disclosure	8,940		0
Estimate of Fair Value Measurement [Member]	'		'
Investment Holdings [Line Items]	'		'
Guaranteed investment contracts - held-to-maturity	$8,205	[3]	$7,285	[3]
[1]	As of SeptemberB 30, 2014, the Company considered the decline in market value of its available-for-sale investments to be temporary in nature and did not consider any of its investments other-than-temporarily impaired.
[2]	As of SeptemberB 30, 2014, the stated maturities of the majority of the Company's student loan asset-backed and other debt securities classified as available-for-sale were greater than 10 years.
[3]	Restricted investments are included in "restricted cash and investments" in the Company's consolidated balance sheets.

Investments_Realized_Gains_Los

Investments Realized Gains (Losses) on Available-for-Sale Securities (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Gain (Loss) on Investments [Line Items]	'	'	'	'
Other income	$8	$730	$8,319	$2,246
Available-for-sale Securities [Member]	'	'	'	'
Gain (Loss) on Investments [Line Items]	'	'	'	'
Other income	8	730	-8,319	2,246
Income tax expense	-3	-270	-3,078	-831
Net	$5	$460	$5,241	$1,415

Business_Combination_Details

Business Combination (Details) (USD $)	Sep. 30, 2014	Dec. 31, 2013	Jun. 03, 2014
In Thousands, unless otherwise specified			RenWeb Acquisition [Member]
Business Acquisition [Line Items]	'	'	'
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Cash and Equivalents	'	'	$326
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Receivables	'	'	961
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment	'	'	105
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Prepaid Expense and Other Assets	'	'	22
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill	'	'	37,188
Goodwill	126,200	117,118	9,082
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Other	'	'	-1,341
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net	'	'	$46,343

Business_Combination_Acquisiti

Business Combination Acquisition Details (Details) (RenWeb Acquisition [Member], USD $)	3 Months Ended	9 Months Ended
	Sep. 30, 2014	Sep. 30, 2014	Jun. 03, 2014
Acquired Finite-Lived Intangible Assets [Line Items]	'	'	'
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill	'	'	$37,188,000
Business Acquisition, Percentage of Voting Interests Acquired	'	'	100.00%
Business Combination, Consideration Transferred	'	44,000,000	'
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, Low	0	0	'
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, High	4,000,000	4,000,000	'
Business Combination, Contingent Consideration, Liability	'	'	2,300,000
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	'18 years	'	'
Business Acquisition, Goodwill, Expected Tax Deductible Amount	9,100,000	9,100,000	'
Customer Relationships [Member]	'	'	'
Acquired Finite-Lived Intangible Assets [Line Items]	'	'	'
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	'20 years	'	'
Finite-lived Intangible Assets Acquired	25,500,000	'	'
Trade Names [Member]	'	'	'
Acquired Finite-Lived Intangible Assets [Line Items]	'	'	'
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	'20 years	'	'
Finite-lived Intangible Assets Acquired	6,400,000	'	'
Computer Software, Intangible Asset [Member]	'	'	'
Acquired Finite-Lived Intangible Assets [Line Items]	'	'	'
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	'5 years	'	'
Finite-lived Intangible Assets Acquired	4,900,000	'	'
Covenants not to compete [Member]	'	'	'
Acquired Finite-Lived Intangible Assets [Line Items]	'	'	'
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	'10 years	'	'
Finite-lived Intangible Assets Acquired	$400,000	'	'

Intangible_Assets_Intangible_A2

Intangible Assets Intangible Assets (Details) (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
Finite-Lived Intangible Assets [Line Items]	'	'
Finite-Lived Intangible Asset, Useful Life (months)	'181 months	'
Finite-Lived Intangible Assets, Net	$42,876	$6,132
Customer Relationships [Member]	'	'
Finite-Lived Intangible Assets [Line Items]	'	'
Finite-Lived Intangible Assets, Accumulated Amortization	22,866	19,821
Finite-Lived Intangible Asset, Useful Life (months)	'207 months	'
Finite-Lived Intangible Assets, Net	28,612	6,132
Computer Software, Intangible Asset [Member]	'	'
Finite-Lived Intangible Assets [Line Items]	'	'
Finite-Lived Intangible Assets, Accumulated Amortization	1,210	0
Finite-Lived Intangible Asset, Useful Life (months)	'44 months	'
Finite-Lived Intangible Assets, Net	7,656	0
Trade Names [Member]	'	'
Finite-Lived Intangible Assets [Line Items]	'	'
Finite-Lived Intangible Assets, Accumulated Amortization	156	0
Finite-Lived Intangible Asset, Useful Life (months)	'236 months	'
Finite-Lived Intangible Assets, Net	6,266	0
Covenants not to compete [Member]	'	'
Finite-Lived Intangible Assets [Line Items]	'	'
Finite-Lived Intangible Assets, Accumulated Amortization	12	0
Finite-Lived Intangible Asset, Useful Life (months)	'116 months	'
Finite-Lived Intangible Assets, Net	$342	$0

Intangible_Assets_Amortization

Intangible Assets Amortization Expense (Details) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013
Finite-Lived Intangible Assets, Amortization Expense, Maturity Schedule [Abstract]	'	'	'	'	'
Amortization of Intangible Assets	$2,000,000	$800,000	$4,400,000	$2,500,000	'
Finite-Lived Intangible Assets, Amortization Expense, Remainder of Fiscal Year	1,984,000	'	1,984,000	'	'
Finite-Lived Intangible Assets, Amortization Expense, Year Two	8,695,000	'	8,695,000	'	'
Finite-Lived Intangible Assets, Amortization Expense, Year Three	5,349,000	'	5,349,000	'	'
Finite-Lived Intangible Assets, Amortization Expense, Year Four	3,862,000	'	3,862,000	'	'
Finite-Lived Intangible Assets, Amortization Expense, Year Five	3,533,000	'	3,533,000	'	'
Finite-Lived Intangible Assets, Amortization Expense, after Year Five	19,453,000	'	19,453,000	'	'
Amortization of Intangible Assets	$42,876,000	'	$42,876,000	'	$6,132,000

Goodwill_Goodwill_Details

Goodwill Goodwill (Details) (USD $)	9 Months Ended
	Sep. 30, 2014
Goodwill [Line Items]	'
Goodwill, Period Start	$117,118,000
Goodwill, Acquired During Period	9,082,000
Goodwill, Period End	126,200,000
Student Loan and Guaranty Servicing [Member]	'
Goodwill [Line Items]	'
Goodwill, Period Start	8,596,000
Goodwill, Acquired During Period	0
Goodwill, Period End	8,596,000
Tuition Payment Processing and Campus Commerce [Member]	'
Goodwill [Line Items]	'
Goodwill, Period Start	58,086,000
Goodwill, Acquired During Period	9,082,000
Goodwill, Period End	67,168,000
Enrollment Services [Member]	'
Goodwill [Line Items]	'
Goodwill, Period Start	8,553,000
Goodwill, Acquired During Period	0
Goodwill, Period End	8,553,000
Asset Generation and Management [Member]	'
Goodwill [Line Items]	'
Goodwill, Period Start	41,883,000
Goodwill, Acquired During Period	0
Goodwill, Period End	$41,883,000

Earnings_per_Common_Share_Deta

Earnings per Common Share (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, except Share data, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]	'	'	'	'
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	0	0	0	0
Net income attributable to Nelnet, Inc.	$85,219	$62,830	$233,999	$232,152
Weighted average common shares outstanding - basic and diluted	46,432,680	46,496,612	46,496,309	46,593,241
Earnings per share - basic and diluted	$1.84	$1.35	$5.03	$4.98
Common shareholders [Member]	'	'	'	'
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]	'	'	'	'
Net income attributable to Nelnet, Inc.	84,330	62,277	231,725	230,141
Weighted average common shares outstanding - basic and diluted	45,948,255	46,086,743	46,044,429	46,189,200
Earnings per share - basic and diluted	$1.84	$1.35	$5.03	$4.98
Unvested restricted stock shareholders [Member]	'	'	'	'
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]	'	'	'	'
Net income attributable to Nelnet, Inc.	$889	$553	$2,274	$2,011
Weighted average common shares outstanding - basic and diluted	484,425	409,869	451,880	404,041
Earnings per share - basic and diluted	$1.84	$1.35	$5.03	$4.98

Segment_Reporting_Details

Segment Reporting (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Segment Reporting Information [Line Items]	'	'	'	'
Total interest income	$189,424	$160,237	$525,247	$476,939
Interest expense	71,937	55,315	201,176	171,800
Net interest income	117,487	104,922	324,071	305,139
Less provision for loan losses	-2,000	-5,000	-6,000	-15,000
Net interest income after provision for loan losses	115,487	99,922	318,071	290,139
Other income (expense):	'	'	'	'
Loan and guaranty servicing revenue	52,659	64,582	183,876	180,261
Intersegment servicing revenue	0	0	0	0
Tuition payment processing and campus commerce revenue	26,399	19,927	73,468	61,694
Enrollment services revenue	22,936	22,563	65,092	76,343
Other income	7,650	8,613	41,096	30,317
Gain on sale of loans and debt repurchases	0	2,138	57	10,900
Derivative market value and foreign currency adjustments, net	29,037	-9,960	38,785	47,841
Derivative settlements, net	-4,834	-6,688	-17,277	-23,229
Total other income (expense)	133,847	101,175	385,097	384,127
Operating expenses:	'	'	'	'
Salaries and benefits	61,098	48,712	167,470	144,049
Cost of Services	14,178	14,668	41,964	51,097
Depreciation and amortization	5,493	4,340	15,490	13,037
Other	36,676	39,887	112,680	109,193
Intersegment expenses, net	0	0	0	0
Total operating expenses	117,445	107,607	337,604	317,376
Income (loss) before income taxes and corporate overhead allocation	131,889	93,490	365,564	356,890
Corporate overhead allocation	0	0	0	0
Income (loss) before income taxes	131,889	93,490	365,564	356,890
Income tax (expense) benefit	-46,513	-30,444	-130,202	-123,637
Net income (loss)	85,376	63,046	235,362	233,253
Net income attributable to noncontrolling interest	157	216	1,363	1,101
Net income (loss) attributable to Nelnet, Inc.	85,219	62,830	233,999	232,152
Student Loan and Guaranty Servicing [Member]	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Total interest income	5	10	25	29
Interest expense	0	0	0	0
Net interest income	5	10	25	29
Less provision for loan losses	0	0	0	0
Net interest income after provision for loan losses	5	10	25	29
Other income (expense):	'	'	'	'
Loan and guaranty servicing revenue	52,659	64,582	183,876	180,261
Intersegment servicing revenue	13,432	13,519	41,453	42,375
Tuition payment processing and campus commerce revenue	0	0	0	0
Enrollment services revenue	0	0	0	0
Other income	0	0	0	0
Gain on sale of loans and debt repurchases	0	0	0	0
Derivative market value and foreign currency adjustments, net	0	0	0	0
Derivative settlements, net	0	0	0	0
Total other income (expense)	66,091	78,101	225,329	222,636
Operating expenses:	'	'	'	'
Salaries and benefits	37,062	29,719	102,462	86,254
Cost of Services	0	0	0	0
Depreciation and amortization	2,558	2,677	8,166	8,197
Other	15,028	19,752	53,295	56,173
Intersegment expenses, net	906	1,457	3,113	3,243
Total operating expenses	55,554	53,605	167,036	153,867
Income (loss) before income taxes and corporate overhead allocation	10,542	24,506	58,318	68,798
Corporate overhead allocation	-2,567	-1,822	-6,487	-4,332
Income (loss) before income taxes	7,975	22,684	51,831	64,466
Income tax (expense) benefit	-3,030	-8,620	-19,695	-24,498
Net income (loss)	4,945	14,064	32,136	39,968
Net income attributable to noncontrolling interest	0	0	0	0
Net income (loss) attributable to Nelnet, Inc.	4,945	14,064	32,136	39,968
Tuition Payment Processing and Campus Commerce [Member]	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Total interest income	2	0	5	0
Interest expense	0	0	0	0
Net interest income	2	0	5	0
Less provision for loan losses	0	0	0	0
Net interest income after provision for loan losses	2	0	5	0
Other income (expense):	'	'	'	'
Loan and guaranty servicing revenue	0	0	0	0
Intersegment servicing revenue	0	0	0	0
Tuition payment processing and campus commerce revenue	26,399	19,927	73,468	61,694
Enrollment services revenue	0	0	0	0
Other income	0	0	0	0
Gain on sale of loans and debt repurchases	0	0	0	0
Derivative market value and foreign currency adjustments, net	0	0	0	0
Derivative settlements, net	0	0	0	0
Total other income (expense)	26,399	19,927	73,468	61,694
Operating expenses:	'	'	'	'
Salaries and benefits	13,288	9,229	34,427	28,015
Cost of Services	0	0	0	0
Depreciation and amortization	2,396	1,117	5,669	3,387
Other	3,312	1,908	8,915	6,387
Intersegment expenses, net	1,481	1,431	4,305	4,350
Total operating expenses	20,477	13,685	53,316	42,139
Income (loss) before income taxes and corporate overhead allocation	5,924	6,242	20,157	19,555
Corporate overhead allocation	-856	-607	-2,163	-1,443
Income (loss) before income taxes	5,068	5,635	17,994	18,112
Income tax (expense) benefit	-1,926	-2,141	-6,837	-6,882
Net income (loss)	3,142	3,494	11,157	11,230
Net income attributable to noncontrolling interest	0	0	0	0
Net income (loss) attributable to Nelnet, Inc.	3,142	3,494	11,157	11,230
Enrollment Services [Member]	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Total interest income	0	0	0	0
Interest expense	0	0	0	0
Net interest income	0	0	0	0
Less provision for loan losses	0	0	0	0
Net interest income after provision for loan losses	0	0	0	0
Other income (expense):	'	'	'	'
Loan and guaranty servicing revenue	0	0	0	0
Intersegment servicing revenue	0	0	0	0
Tuition payment processing and campus commerce revenue	0	0	0	0
Enrollment services revenue	22,936	22,563	65,092	76,343
Other income	0	0	0	0
Gain on sale of loans and debt repurchases	0	0	0	0
Derivative market value and foreign currency adjustments, net	0	0	0	0
Derivative settlements, net	0	0	0	0
Total other income (expense)	22,936	22,563	65,092	76,343
Operating expenses:	'	'	'	'
Salaries and benefits	4,474	4,491	12,986	15,067
Cost of Services	14,178	14,668	41,964	51,097
Depreciation and amortization	41	57	129	179
Other	1,624	1,556	4,917	4,450
Intersegment expenses, net	761	1,139	2,711	3,418
Total operating expenses	21,078	21,911	62,707	74,211
Income (loss) before income taxes and corporate overhead allocation	1,858	652	2,385	2,132
Corporate overhead allocation	-855	-607	-2,162	-1,443
Income (loss) before income taxes	1,003	45	223	689
Income tax (expense) benefit	-381	-17	-85	-261
Net income (loss)	622	28	138	428
Net income attributable to noncontrolling interest	0	0	0	0
Net income (loss) attributable to Nelnet, Inc.	622	28	138	428
Total Fee-Based [Member]	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Total interest income	7	10	30	29
Interest expense	0	0	0	0
Net interest income	7	10	30	29
Less provision for loan losses	0	0	0	0
Net interest income after provision for loan losses	7	10	30	29
Other income (expense):	'	'	'	'
Loan and guaranty servicing revenue	52,659	64,582	183,876	180,261
Intersegment servicing revenue	13,432	13,519	41,453	42,375
Tuition payment processing and campus commerce revenue	26,399	19,927	73,468	61,694
Enrollment services revenue	22,936	22,563	65,092	76,343
Other income	0	0	0	0
Gain on sale of loans and debt repurchases	0	0	0	0
Derivative market value and foreign currency adjustments, net	0	0	0	0
Derivative settlements, net	0	0	0	0
Total other income (expense)	115,426	120,591	363,889	360,673
Operating expenses:	'	'	'	'
Salaries and benefits	54,824	43,439	149,875	129,336
Cost of Services	14,178	14,668	41,964	51,097
Depreciation and amortization	4,995	3,851	13,964	11,763
Other	19,964	23,216	67,127	67,010
Intersegment expenses, net	3,148	4,027	10,129	11,011
Total operating expenses	97,109	89,201	283,059	270,217
Income (loss) before income taxes and corporate overhead allocation	18,324	31,400	80,860	90,485
Corporate overhead allocation	-4,278	-3,036	-10,812	-7,218
Income (loss) before income taxes	14,046	28,364	70,048	83,267
Income tax (expense) benefit	-5,337	-10,778	-26,617	-31,641
Net income (loss)	8,709	17,586	43,431	51,626
Net income attributable to noncontrolling interest	0	0	0	0
Net income (loss) attributable to Nelnet, Inc.	8,709	17,586	43,431	51,626
Asset Generation and Management [Member]	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Total interest income	187,949	158,793	520,514	472,622
Interest expense	71,037	56,100	198,449	170,502
Net interest income	116,912	102,693	322,065	302,120
Less provision for loan losses	-2,000	-5,000	-6,000	-15,000
Net interest income after provision for loan losses	114,912	97,693	316,065	287,120
Other income (expense):	'	'	'	'
Loan and guaranty servicing revenue	0	0	0	0
Intersegment servicing revenue	0	0	0	0
Tuition payment processing and campus commerce revenue	0	0	0	0
Enrollment services revenue	0	0	0	0
Other income	4,294	3,981	12,954	11,207
Gain on sale of loans and debt repurchases	0	2,138	57	10,900
Derivative market value and foreign currency adjustments, net	29,430	-12,660	41,755	35,711
Derivative settlements, net	-4,575	-6,432	-16,510	-21,816
Total other income (expense)	29,149	-12,973	38,256	36,002
Operating expenses:	'	'	'	'
Salaries and benefits	565	555	1,744	1,709
Cost of Services	0	0	0	0
Depreciation and amortization	0	0	0	0
Other	8,636	7,939	24,627	23,375
Intersegment expenses, net	13,611	13,705	41,950	42,955
Total operating expenses	22,812	22,199	68,321	68,039
Income (loss) before income taxes and corporate overhead allocation	121,249	62,521	286,000	255,083
Corporate overhead allocation	-1,026	-1,302	-3,604	-3,095
Income (loss) before income taxes	120,223	61,219	282,396	251,988
Income tax (expense) benefit	-45,684	-23,263	-107,309	-95,755
Net income (loss)	74,539	37,956	175,087	156,233
Net income attributable to noncontrolling interest	0	0	0	0
Net income (loss) attributable to Nelnet, Inc.	74,539	37,956	175,087	156,233
Corporate and Other [Member]	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Total interest income	1,814	2,201	6,508	6,708
Interest expense	1,246	-18	4,532	3,718
Net interest income	568	2,219	1,976	2,990
Less provision for loan losses	0	0	0	0
Net interest income after provision for loan losses	568	2,219	1,976	2,990
Other income (expense):	'	'	'	'
Loan and guaranty servicing revenue	0	0	0	0
Intersegment servicing revenue	0	0	0	0
Tuition payment processing and campus commerce revenue	0	0	0	0
Enrollment services revenue	0	0	0	0
Other income	3,356	4,632	28,142	19,110
Gain on sale of loans and debt repurchases	0	0	0	0
Derivative market value and foreign currency adjustments, net	-393	2,700	-2,970	12,130
Derivative settlements, net	-259	-256	-767	-1,413
Total other income (expense)	2,704	7,076	24,405	29,827
Operating expenses:	'	'	'	'
Salaries and benefits	5,709	4,718	15,851	13,004
Cost of Services	0	0	0	0
Depreciation and amortization	498	489	1,526	1,274
Other	8,076	8,732	20,926	18,808
Intersegment expenses, net	-3,327	-4,213	-10,626	-11,591
Total operating expenses	10,956	9,726	27,677	21,495
Income (loss) before income taxes and corporate overhead allocation	-7,684	-431	-1,296	11,322
Corporate overhead allocation	5,304	4,338	14,416	10,313
Income (loss) before income taxes	-2,380	3,907	13,120	21,635
Income tax (expense) benefit	4,508	3,597	3,724	3,759
Net income (loss)	2,128	7,504	16,844	25,394
Net income attributable to noncontrolling interest	157	216	1,363	1,101
Net income (loss) attributable to Nelnet, Inc.	1,971	7,288	15,481	24,293
Intersegment Eliminations [Member]	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Total interest income	-346	-767	-1,805	-2,420
Interest expense	-346	-767	-1,805	-2,420
Net interest income	0	0	0	0
Less provision for loan losses	0	0	0	0
Net interest income after provision for loan losses	0	0	0	0
Other income (expense):	'	'	'	'
Loan and guaranty servicing revenue	0	0	0	0
Intersegment servicing revenue	-13,432	-13,519	-41,453	-42,375
Tuition payment processing and campus commerce revenue	0	0	0	0
Enrollment services revenue	0	0	0	0
Other income	0	0	0	0
Gain on sale of loans and debt repurchases	0	0	0	0
Derivative market value and foreign currency adjustments, net	0	0	0	0
Derivative settlements, net	0	0	0	0
Total other income (expense)	-13,432	-13,519	-41,453	-42,375
Operating expenses:	'	'	'	'
Salaries and benefits	0	0	0	0
Cost of Services	0	0	0	0
Depreciation and amortization	0	0	0	0
Other	0	0	0	0
Intersegment expenses, net	-13,432	-13,519	-41,453	-42,375
Total operating expenses	-13,432	-13,519	-41,453	-42,375
Income (loss) before income taxes and corporate overhead allocation	0	0	0	0
Corporate overhead allocation	0	0	0	0
Income (loss) before income taxes	0	0	0	0
Income tax (expense) benefit	0	0	0	0
Net income (loss)	0	0	0	0
Net income attributable to noncontrolling interest	0	0	0	0
Net income (loss) attributable to Nelnet, Inc.	$0	$0	$0	$0

Major_Customer_Details

Major Customer (Details) (USD $)	3 Months Ended		9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Concentration Risk [Line Items]	'	'	'	'
Concentration Risk, Customer	'Department of Education	'Department of Education	'Department of Education	'Department of Education
Concentration Risk Dollar Value [Member]	'	'	'	'
Concentration Risk [Line Items]	'	'	'	'
Loan and guaranty servicing revenue	31.2	26	92.1	68.4

Related_Party_Transactions_Tra

Related Party Transactions Transactions with Union Bank and Trust (Details) (Union Bank and Trust Company [Member], USD $)	Sep. 30, 2014
	BasisPoints
Union Bank and Trust Company [Member]	'
Related Party Transaction [Line Items]	'
Amount of Participation	$2,200,000
Contractual Obligation	$900,000
basis points earned on outstanding balance	40

Assets_and_Liabilities_that_ar

Assets and Liabilities that are Measured at Fair Value (Details) (Fair Value, Measurements, Recurring [Member], USD $)	Sep. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Assets, Fair Value Disclosure [Abstract]	'	'
Investments	$147,780	$192,040
Fair value of derivative instruments	68,009	62,507
Total assets	215,789	254,547
Liabilities, Fair Value Disclosure [Abstract]	'	'
Fair value of derivative instruments	14,814	17,969
Total liabilities	14,814	17,969
Student loan asset-backed securities [Member]	'	'
Assets, Fair Value Disclosure [Abstract]	'	'
Investments	143,955	188,279
Equity securities [Member]	'	'
Assets, Fair Value Disclosure [Abstract]	'	'
Investments, Fair Value Disclosure	3,416	3,282
Debt securities [Member]	'	'
Assets, Fair Value Disclosure [Abstract]	'	'
Investments, Fair Value Disclosure	409	479
Level 1 [Member]	'	'
Assets, Fair Value Disclosure [Abstract]	'	'
Investments	3,825	3,761
Fair value of derivative instruments	0	0
Total assets	3,825	3,761
Liabilities, Fair Value Disclosure [Abstract]	'	'
Fair value of derivative instruments	0	0
Total liabilities	0	0
Level 1 [Member] | Student loan asset-backed securities [Member]	'	'
Assets, Fair Value Disclosure [Abstract]	'	'
Investments	0	0
Level 1 [Member] | Equity securities [Member]	'	'
Assets, Fair Value Disclosure [Abstract]	'	'
Investments, Fair Value Disclosure	3,416	3,282
Level 1 [Member] | Debt securities [Member]	'	'
Assets, Fair Value Disclosure [Abstract]	'	'
Investments, Fair Value Disclosure	409	479
Level 2 [Member]	'	'
Assets, Fair Value Disclosure [Abstract]	'	'
Investments	143,955	188,279
Fair value of derivative instruments	68,009	62,507
Total assets	211,964	250,786
Liabilities, Fair Value Disclosure [Abstract]	'	'
Fair value of derivative instruments	14,814	17,969
Total liabilities	14,814	17,969
Level 2 [Member] | Student loan asset-backed securities [Member]	'	'
Assets, Fair Value Disclosure [Abstract]	'	'
Investments	143,955	188,279
Level 2 [Member] | Equity securities [Member]	'	'
Assets, Fair Value Disclosure [Abstract]	'	'
Investments, Fair Value Disclosure	0	0
Level 2 [Member] | Debt securities [Member]	'	'
Assets, Fair Value Disclosure [Abstract]	'	'
Investments, Fair Value Disclosure	$0	$0

Fair_Value_of_Financial_Instru

Fair Value of Financial Instruments (Details) (USD $)	Sep. 30, 2014	Dec. 31, 2013	Sep. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Assets, Fair Value Disclosure [Abstract]	'	'	'	'
Student loans receivable	$28,701,344	$25,907,589	'	'
Cash and cash equivalents	74,579	63,267	51,391	66,031
Investments	147,780	192,040	'	'
Restricted cash - due to customers	72,836	167,576	'	'
Accrued interest receivable	352,205	314,553	'	'
Derivative instruments	68,009	62,507	'	'
Liabilities, Fair Value Disclosure [Abstract]	'	'	'	'
Bonds and notes payable	28,737,456	25,955,289	'	'
Accrued interest payable	25,221	21,725	'	'
Due to customers	72,836	167,576	'	'
Derivative instruments	14,814	17,969	'	'
Fair value [Member]	'	'	'	'
Assets, Fair Value Disclosure [Abstract]	'	'	'	'
Student loans receivable	29,975,188	26,641,383	'	'
Cash and cash equivalents	74,579	63,267	'	'
Investments	147,780	192,040	'	'
Restricted cash	859,302	727,838	'	'
Restricted cash - due to customers	72,836	167,576	'	'
Restricted investments	8,205	7,285	'	'
Accrued interest receivable	352,205	314,553	'	'
Derivative instruments	68,009	62,507	'	'
Liabilities, Fair Value Disclosure [Abstract]	'	'	'	'
Bonds and notes payable	28,738,353	25,577,250	'	'
Accrued interest payable	25,221	21,725	'	'
Due to customers	72,836	167,576	'	'
Derivative instruments	14,814	17,969	'	'
Fair value [Member] | Level 1 [Member]	'	'	'	'
Assets, Fair Value Disclosure [Abstract]	'	'	'	'
Student loans receivable	0	0	'	'
Cash and cash equivalents	74,579	63,267	'	'
Investments	3,825	3,761	'	'
Restricted cash	859,302	727,838	'	'
Restricted cash - due to customers	72,836	167,576	'	'
Restricted investments	8,205	7,285	'	'
Accrued interest receivable	0	0	'	'
Derivative instruments	0	0	'	'
Liabilities, Fair Value Disclosure [Abstract]	'	'	'	'
Bonds and notes payable	0	0	'	'
Accrued interest payable	0	0	'	'
Due to customers	72,836	167,576	'	'
Derivative instruments	0	0	'	'
Fair value [Member] | Level 2 [Member]	'	'	'	'
Assets, Fair Value Disclosure [Abstract]	'	'	'	'
Student loans receivable	0	0	'	'
Cash and cash equivalents	0	0	'	'
Investments	143,955	188,279	'	'
Restricted cash	0	0	'	'
Restricted cash - due to customers	0	0	'	'
Restricted investments	0	0	'	'
Accrued interest receivable	352,205	314,553	'	'
Derivative instruments	68,009	62,507	'	'
Liabilities, Fair Value Disclosure [Abstract]	'	'	'	'
Bonds and notes payable	28,738,353	25,577,250	'	'
Accrued interest payable	25,221	21,725	'	'
Due to customers	0	0	'	'
Derivative instruments	14,814	17,969	'	'
Fair value [Member] | Level 3 [Member]	'	'	'	'
Assets, Fair Value Disclosure [Abstract]	'	'	'	'
Student loans receivable	29,975,188	26,641,383	'	'
Cash and cash equivalents	0	0	'	'
Investments	0	0	'	'
Restricted cash	0	0	'	'
Restricted cash - due to customers	0	0	'	'
Restricted investments	0	0	'	'
Accrued interest receivable	0	0	'	'
Derivative instruments	0	0	'	'
Liabilities, Fair Value Disclosure [Abstract]	'	'	'	'
Bonds and notes payable	0	0	'	'
Accrued interest payable	0	0	'	'
Due to customers	0	0	'	'
Derivative instruments	0	0	'	'
Carrying value [Member]	'	'	'	'
Assets, Fair Value Disclosure [Abstract]	'	'	'	'
Student loans receivable	28,701,344	25,907,589	'	'
Cash and cash equivalents	74,579	63,267	'	'
Investments	147,780	192,040	'	'
Restricted cash	859,302	727,838	'	'
Restricted cash - due to customers	72,836	167,576	'	'
Restricted investments	8,205	7,285	'	'
Accrued interest receivable	352,205	314,553	'	'
Derivative instruments	68,009	62,507	'	'
Liabilities, Fair Value Disclosure [Abstract]	'	'	'	'
Bonds and notes payable	28,737,456	25,955,289	'	'
Accrued interest payable	25,221	21,725	'	'
Due to customers	72,836	167,576	'	'
Derivative instruments	$14,814	$17,969	'	'

Legal_Proceedings_Details

Legal Proceedings (Details) (Pending or Threatened Litigation [Member], USD $)	9 Months Ended
	Sep. 30, 2014
Loss Contingencies [Line Items]	'
Loss contingency, inestimable loss	'The Company has accrued an immaterial amount related to the legal proceedings described below. However, due to the uncertainty and risks inherent in class determination and the overall litigation process, the Company believes that a meaningful estimate of its exposure to any reasonably possible losses or range of reasonably possible losses, in excess of the amount accrued, cannot currently be made.
Bais Yaakov of Spring Valley v. Peterson's Nelnet, LLC [Member]	'
Loss Contingencies [Line Items]	'
Loss contingency, actions taken by court, arbitrator or mediator	'As of the filing date of this report, the New Jersey District Court has not established, recognized, or certified a class.
Bais Yaakov of Spring Valley v. Peterson's Nelnet, LLC [Member] | Named plaintiff [Member]	'
Loss Contingencies [Line Items]	'
Advertising faxes	6
Loss Contingency, Damages Sought, Value, Per Violation	500
Bais Yaakov of Spring Valley v. Peterson's Nelnet, LLC [Member] | Class action members [Member]	'
Loss Contingencies [Line Items]	'
Advertising faxes	10,000
Loss contingency, damages sought, value	5,000,000
Loss contingency, damages sought, value if trebled	15,000,000
Than Zaw v. Nelnet, Inc. [Member]	'
Loss Contingencies [Line Items]	'
Loss contingency, actions taken by court, arbitrator or mediator	'As of the filing date of this report, the California District Court has not established, recognized, or certified a class.
Than Zaw v. Nelnet, Inc. [Member] | Named plaintiff [Member]	'
Loss Contingencies [Line Items]	'
Loss Contingency, Damages Sought, Value, Per Violation	5,000
Grant Keating v. Peterson's Nelnet, LLC et al [Member]	'
Loss Contingencies [Line Items]	'
Loss contingency, actions taken by court, arbitrator or mediator	'As of the filing date of this report, the Ohio District Court has not established, recognized, or certified a class.
Grant Keating v. Peterson's Nelnet, LLC et al [Member] | Named plaintiff [Member]	'
Loss Contingencies [Line Items]	'
Loss Contingency, Damages Sought, Value, Per Violation	500