Segment Reporting - Asset Information for Loans Segment (Detail) - USD ($) $ in Millions |
Sep. 30, 2026 |
Dec. 31, 2025 |
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| Segment Reporting Information [Line Items] | ||||||
| Other | $ 2,413 | $ 2,385 | ||||
| Total assets | 46,128 | 48,681 | ||||
| Consumer Lending [Member] | ||||||
| Segment Reporting Information [Line Items] | ||||||
| Loans, net | 15,254 | 15,451 | ||||
| Cash and investments | [1] | 532 | 529 | |||
| Other | 593 | 565 | ||||
| Total assets | 16,379 | 16,545 | ||||
| Federal Education Loans [Member] | ||||||
| Segment Reporting Information [Line Items] | ||||||
| Loans, net | 25,898 | 28,141 | ||||
| Cash and investments | [2] | 848 | 1,034 | |||
| Other | 1,641 | 1,681 | ||||
| Total assets | $ 28,387 | $ 30,856 | ||||
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- Definition Sum of cash and investments, including restricted cash and investments, as of the balance sheet date. No definition available.
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- Definition Amount of asset recognized for present right to economic benefit. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of interest receivable and assets classified as other. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amortized cost, after allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement and net investment in lease. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- 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. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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