Impairment Of Venture Capital

No definition available.

Name:	nni_ImpairmentOfVentureCapital
Namespace Prefix:	nni_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Provision (Negative Provision) Of Beneficial Interest In Investments

+ References

No definition available.

+ Details

Name:	nni_ProvisionNegativeProvisionOfBeneficialInterestInInvestments
Namespace Prefix:	nni_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

+ References

+ Details

Name:	us-gaap_AssetImpairmentCharges
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The aggregate amount of write-downs for impairments recognized during the period for long lived assets held for use (including those held for disposal by means other than sale).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Subparagraph (b)
-SubTopic 10
-Topic 230
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-28

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 220
-SubTopic 40
-Name Accounting Standards Codification
-Section 55
-Paragraph 11
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147476153/220-40-55-11

Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 100
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482078/820-10-55-100

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 360
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482099/360-10-50-2

Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 45
-Paragraph 4
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482130/360-10-45-4

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 21
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147476148/220-40-50-21

+ Details

Name:	us-gaap_ImpairmentOfLongLivedAssetsHeldForUse
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The charge against earnings resulting from the write down of long lived assets other than goodwill due to the difference between the carrying value and lower fair value.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-28

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 360
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482099/360-10-50-2

+ Details

Name:	us-gaap_OtherAssetImpairmentCharges
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_SegmentReportingInformationLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis=nni_SolarInvestmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_PropertyPlantAndEquipmentByTypeAxis=nni_LeasesBuildingsAndImprovementsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_ConsolidationItemsAxis=us-gaap_OperatingSegmentsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=nni_LoanServicingAndSystemsSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=nni_EducationTechnologyServicesAndPaymentsSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=nni_AssetGenerationAndManagementSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=nni_NelnetBankMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_ConsolidationItemsAxis=us-gaap_MaterialReconcilingItemsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_ConsolidationItemsAxis=us-gaap_CorporateNonSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Impairment Expense and Provision for Beneficial Interests - Schedule of Impairment Charges by Asset and Segment (Details) - USD ($) $ in Thousands	3 Months Ended			6 Months Ended
	Jun. 30, 2025	Mar. 31, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Segment Reporting Information [Line Items]
Investments - beneficial interest in loan securitizations	$ 4,977	$ 1,500	$ 5,911	$ 6,487	$ 5,911
Investments - venture capital	140			140	37
Impairment expense and provision for beneficial interests	10,288		7,776	11,879	7,813
Solar
Segment Reporting Information [Line Items]
Property and equipment - solar facilities	1,902		1,170	1,902	1,170
Other assets - solar inventory			695		695
Leases, buildings, and associated improvements
Segment Reporting Information [Line Items]
Property and equipment - solar facilities	3,269			3,350
Operating Segments \| Loan Servicing and Systems (LSS)
Segment Reporting Information [Line Items]
Investments - beneficial interest in loan securitizations	0		0	0	0
Investments - venture capital	0			0	0
Impairment expense and provision for beneficial interests	0		0	0	0
Operating Segments \| Loan Servicing and Systems (LSS) \| Solar
Segment Reporting Information [Line Items]
Property and equipment - solar facilities	0		0	0	0
Other assets - solar inventory			0		0
Operating Segments \| Loan Servicing and Systems (LSS) \| Leases, buildings, and associated improvements
Segment Reporting Information [Line Items]
Property and equipment - solar facilities	0			0
Operating Segments \| Education Technology Services and Payments (ETSP)
Segment Reporting Information [Line Items]
Investments - beneficial interest in loan securitizations	0		0	0	0
Investments - venture capital	0			0	0
Impairment expense and provision for beneficial interests	0		0	0	0
Operating Segments \| Education Technology Services and Payments (ETSP) \| Solar
Segment Reporting Information [Line Items]
Property and equipment - solar facilities	0		0	0	0
Other assets - solar inventory			0		0
Operating Segments \| Education Technology Services and Payments (ETSP) \| Leases, buildings, and associated improvements
Segment Reporting Information [Line Items]
Property and equipment - solar facilities	0			0
Operating Segments \| Asset Generation and Management
Segment Reporting Information [Line Items]
Investments - beneficial interest in loan securitizations	4,977		5,911	6,487	5,911
Investments - venture capital	0			0	0
Impairment expense and provision for beneficial interests	4,977		5,911	6,487	5,911
Operating Segments \| Asset Generation and Management \| Solar
Segment Reporting Information [Line Items]
Property and equipment - solar facilities	0		0	0	0
Other assets - solar inventory			0		0
Operating Segments \| Asset Generation and Management \| Leases, buildings, and associated improvements
Segment Reporting Information [Line Items]
Property and equipment - solar facilities	0			0
Operating Segments \| Nelnet Bank
Segment Reporting Information [Line Items]
Investments - beneficial interest in loan securitizations	0		0	0	0
Investments - venture capital	0			0	0
Impairment expense and provision for beneficial interests	0		0	0	0
Operating Segments \| Nelnet Bank \| Solar
Segment Reporting Information [Line Items]
Property and equipment - solar facilities	0		0	0	0
Other assets - solar inventory			0		0
Operating Segments \| Nelnet Bank \| Leases, buildings, and associated improvements
Segment Reporting Information [Line Items]
Property and equipment - solar facilities	0			0
NFS Other Operating Segments
Segment Reporting Information [Line Items]
Investments - beneficial interest in loan securitizations	0		0	0	0
Investments - venture capital	0			0	0
Impairment expense and provision for beneficial interests	0		0	81	0
NFS Other Operating Segments \| Solar
Segment Reporting Information [Line Items]
Property and equipment - solar facilities	0		0	0	0
Other assets - solar inventory			0		0
NFS Other Operating Segments \| Leases, buildings, and associated improvements
Segment Reporting Information [Line Items]
Property and equipment - solar facilities	0			81
Corporate and Other Activities
Segment Reporting Information [Line Items]
Investments - beneficial interest in loan securitizations	0		0	0	0
Investments - venture capital	140			140	37
Impairment expense and provision for beneficial interests	5,311		1,865	5,311	1,902
Corporate and Other Activities \| Solar
Segment Reporting Information [Line Items]
Property and equipment - solar facilities	1,902		1,170	1,902	1,170
Other assets - solar inventory			$ 695		$ 695
Corporate and Other Activities \| Leases, buildings, and associated improvements
Segment Reporting Information [Line Items]
Property and equipment - solar facilities	$ 3,269			$ 3,269