Related Party Transactions and Exempt Party-in-Interest Transactions - Additional Information (Details) - EBP 003 - USD ($)	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024
EBP, Related Party and Party-in-Interest Transactions [Line Items]
Investments held	$ 911,788,553	$ 789,443,230
Charles Schwab
EBP, Related Party and Party-in-Interest Transactions [Line Items]
Payment of fees for trust and record keeping services	$ 21,450	$ 21,825
Common Stock \| Charles Schwab
EBP, Related Party and Party-in-Interest Transactions [Line Items]
Shares of common stock held by the plan	253,135	250,787
Cost basis	$ 13,771,753	$ 13,525,925
Market value	17,572,606	14,676,035
Dividend income	681,267
Schwab U.S. Treasury Money Fund \| Charles Schwab
EBP, Related Party and Party-in-Interest Transactions [Line Items]
Investments held	$ 2,784	$ 23,425

Employee benefit plan, payment of fees for trust and record keeping services.

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- Definition

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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Fair value of investment, excluding plan interest in master trust, held by employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). Includes, but is not limited to, derivative, investment measured at net asset value per share as practical expedient, and insurance contract not meeting fully-benefit responsive investment criteria.

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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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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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