Related-Party Transactions and Party-In-Interest Transactions (Details) - Navient 401(k) Savings Plan [Member] - USD ($)	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024
Related-Party Transactions and Party-In-Interest Transactions [Abstract]
Other income	$ 113,561
Common Stock Fund [Member]
Related-Party Transactions and Party-In-Interest Transactions [Abstract]
Shares held (in Shares)	588,672	708,340
Estimated fair value	$ 6,016,875	$ 7,390,479
Number of units purchased (in Shares)	49,602
Purchase of company stock	$ 516,676
Number of units sold (in Shares)	169,270
Sale of company stock	$ 1,752,506
Dividend income	$ 320,605

Amount of increase (decrease) in net asset available for benefit from investment income (loss) on investment held by employee stock purchase, saving, or similar plan (employee benefit plan (EBP)), classified as other.

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Amount of increase in net asset available for benefit from dividend income on investment held by employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

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Cost of investment, excluding plan interest in master trust, acquired by employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

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Number of shares or units of investment held by employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

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Number of shares or units of investment purchased by employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

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Number of shares or units of investment sold by employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

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Fair value of plan interest in master trust held by employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

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Amount of selling price for investment, excluding plan interest in master trust, sold by employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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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.

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