Acquisitions and Discontinued Operations (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
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	$ 313	$ 434

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
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
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