Discontinued Operations (Details) - USD ($) $ in Millions	Sep. 30, 2025	Dec. 31, 2024
Discontinued operations \| Government Guaranteed Loans \| Government-guaranteed And Private Education Lending Business
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Loans included in divestiture	$ 216	$ 257

Amount classified as accounts, notes and loans receivable attributable to disposal group held for sale or disposed of.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
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-Topic 205
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 205
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 360
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-Name Accounting Standards Codification
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-Paragraph 3
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 205
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-Name Accounting Standards Codification
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant