Additional Proceeds from Sale of Debt Securities, Available-for-sale

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of realized gain on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-9

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481544/470-10-50-6

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481544/470-10-50-6

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(f))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480678/235-10-S99-1

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of cash inflow from sale of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 11
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481830/320-10-45-11

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-9

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-12

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 11
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-11

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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Borrowings - Securities Financing Transactions (Details) - Private Education Loans - USD ($) $ in Thousands	Jun. 28, 2024	Apr. 11, 2024	Apr. 09, 2024	Mar. 13, 2024	Nov. 07, 2023	May 24, 2023
2023-B ABS transaction
Line of Credit Facility [Line Items]
Loans Transferred to the Trust by Third-Party Seller						$ 1,988,277
Additional Loans the Bank Transferred to the Trust						104,743
Gain on Sale for Additional Loans Transferred by Bank						$ 5,391
2023-D ABS transaction
Line of Credit Facility [Line Items]
Loans Transferred to the Trust by Third-Party Seller					$ 995,184
Additional Loans the Bank Transferred to the Trust					52,572
Gain on Sale for Additional Loans Transferred by Bank					$ 1,570
2024-A ABS transaction
Line of Credit Facility [Line Items]
Loans Transferred to the Trust by Third-Party Seller				$ 1,988,248
Additional Loans the Bank Transferred to the Trust				104,748
Gain on Sale for Additional Loans Transferred by Bank				$ 6,685
2024-R1 ABS transaction
Line of Credit Facility [Line Items]
Loans Transferred to the Trust by Third-Party Seller			$ 68,896
Additional Loans the Bank Transferred to the Trust			0
Gain on Sale for Additional Loans Transferred by Bank			$ 0
2024-B ABS transaction
Line of Credit Facility [Line Items]
Loans Transferred to the Trust by Third-Party Seller		$ 191,445
Additional Loans the Bank Transferred to the Trust		10,132
Gain on Sale for Additional Loans Transferred by Bank		$ 35
2024-D ABS transaction
Line of Credit Facility [Line Items]
Loans Transferred to the Trust by Third-Party Seller	$ 1,494,953
Additional Loans the Bank Transferred to the Trust	78,782
Gain on Sale for Additional Loans Transferred by Bank	$ 6,051