v3.25.2
Shareholder Report, Holdings (Details)
Jun. 30, 2025
Schwab Prime Advantage Money Fund - Investor Shares | 1 to 7 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 77.10%
Schwab Prime Advantage Money Fund - Investor Shares | 8 to 30 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 3.30%
Schwab Prime Advantage Money Fund - Investor Shares | 31 to 60 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 7.90%
Schwab Prime Advantage Money Fund - Investor Shares | 61 to 90 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 3.30%
Schwab Prime Advantage Money Fund - Investor Shares | 91 to 180 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 4.40%
Schwab Prime Advantage Money Fund - Investor Shares | Over 180 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 4.00%
Schwab Prime Advantage Money Fund - Investor Shares | Repurchase Agreements Other [Member]  
Holdings [Line Items]  
Percent of Total Investments 5.50%
Schwab Prime Advantage Money Fund - Investor Shares | Certificates of Deposit [Member]  
Holdings [Line Items]  
Percent of Total Investments 24.20%
Schwab Prime Advantage Money Fund - Investor Shares | Financial Company Commercial Paper [Member]  
Holdings [Line Items]  
Percent of Total Investments 12.20%
Schwab Prime Advantage Money Fund - Investor Shares | Non-Negotiable Time Deposits [Member]  
Holdings [Line Items]  
Percent of Total Investments 9.80%
Schwab Prime Advantage Money Fund - Investor Shares | Asset-Backed Commercial Paper [Member]  
Holdings [Line Items]  
Percent of Total Investments 9.60%
Schwab Prime Advantage Money Fund - Investor Shares | Non-Financial Company Commercial Paper [Member]  
Holdings [Line Items]  
Percent of Total Investments 0.90%
Schwab Prime Advantage Money Fund - Investor Shares | Other Instruments [Member]  
Holdings [Line Items]  
Percent of Total Investments 0.40%
Schwab Prime Advantage Money Fund - Investor Shares | Repurchase Agreements [Member]  
Holdings [Line Items]  
Percent of Total Investments 42.30%
Schwab Prime Advantage Money Fund - Investor Shares | Repurchase Agreements U.S. Government Agency [Member]  
Holdings [Line Items]  
Percent of Total Investments 16.40%
Schwab Prime Advantage Money Fund - Investor Shares | Repurchase Agreements U.S. Treasury [Member]  
Holdings [Line Items]  
Percent of Total Investments 20.40%
Schwab Prime Advantage Money Fund - Investor Shares | Variable Rate Demand Notes [Member]  
Holdings [Line Items]  
Percent of Total Investments 0.60%
Schwab Prime Advantage Money Fund - Ultra Shares | 1 to 7 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 77.10%
Schwab Prime Advantage Money Fund - Ultra Shares | 8 to 30 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 3.30%
Schwab Prime Advantage Money Fund - Ultra Shares | 31 to 60 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 7.90%
Schwab Prime Advantage Money Fund - Ultra Shares | 61 to 90 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 3.30%
Schwab Prime Advantage Money Fund - Ultra Shares | 91 to 180 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 4.40%
Schwab Prime Advantage Money Fund - Ultra Shares | Over 180 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 4.00%
Schwab Prime Advantage Money Fund - Ultra Shares | Repurchase Agreements Other [Member]  
Holdings [Line Items]  
Percent of Total Investments 5.50%
Schwab Prime Advantage Money Fund - Ultra Shares | Certificates of Deposit [Member]  
Holdings [Line Items]  
Percent of Total Investments 24.20%
Schwab Prime Advantage Money Fund - Ultra Shares | Financial Company Commercial Paper [Member]  
Holdings [Line Items]  
Percent of Total Investments 12.20%
Schwab Prime Advantage Money Fund - Ultra Shares | Non-Negotiable Time Deposits [Member]  
Holdings [Line Items]  
Percent of Total Investments 9.80%
Schwab Prime Advantage Money Fund - Ultra Shares | Asset-Backed Commercial Paper [Member]  
Holdings [Line Items]  
Percent of Total Investments 9.60%
Schwab Prime Advantage Money Fund - Ultra Shares | Non-Financial Company Commercial Paper [Member]  
Holdings [Line Items]  
Percent of Total Investments 0.90%
Schwab Prime Advantage Money Fund - Ultra Shares | Other Instruments [Member]  
Holdings [Line Items]  
Percent of Total Investments 0.40%
Schwab Prime Advantage Money Fund - Ultra Shares | Repurchase Agreements [Member]  
Holdings [Line Items]  
Percent of Total Investments 42.30%
Schwab Prime Advantage Money Fund - Ultra Shares | Repurchase Agreements U.S. Government Agency [Member]  
Holdings [Line Items]  
Percent of Total Investments 16.40%
Schwab Prime Advantage Money Fund - Ultra Shares | Repurchase Agreements U.S. Treasury [Member]  
Holdings [Line Items]  
Percent of Total Investments 20.40%
Schwab Prime Advantage Money Fund - Ultra Shares | Variable Rate Demand Notes [Member]  
Holdings [Line Items]  
Percent of Total Investments 0.60%
Schwab Government Money Fund - Sweep Shares | 1 to 7 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 82.80%
Schwab Government Money Fund - Sweep Shares | 8 to 30 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 1.00%
Schwab Government Money Fund - Sweep Shares | 31 to 60 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 3.30%
Schwab Government Money Fund - Sweep Shares | 61 to 90 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 1.10%
Schwab Government Money Fund - Sweep Shares | 91 to 180 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 1.60%
Schwab Government Money Fund - Sweep Shares | Over 180 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 10.20%
Schwab Government Money Fund - Sweep Shares | Repurchase Agreements [Member]  
Holdings [Line Items]  
Percent of Total Investments 62.20%
Schwab Government Money Fund - Sweep Shares | Repurchase Agreements U.S. Government Agency [Member]  
Holdings [Line Items]  
Percent of Total Investments 37.00%
Schwab Government Money Fund - Sweep Shares | Repurchase Agreements U.S. Treasury [Member]  
Holdings [Line Items]  
Percent of Total Investments 25.20%
Schwab Government Money Fund - Sweep Shares | U.S. Government Agency Debt [Member]  
Holdings [Line Items]  
Percent of Total Investments 31.40%
Schwab Government Money Fund - Sweep Shares | U.S. Treasury Debt [Member]  
Holdings [Line Items]  
Percent of Total Investments 6.20%
Schwab Government Money Fund - Sweep Shares | Variable Rate Demand Notes [Member]  
Holdings [Line Items]  
Percent of Total Investments 0.20%
Schwab Government Money Fund - Investor Shares | 1 to 7 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 82.80%
Schwab Government Money Fund - Investor Shares | 8 to 30 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 1.00%
Schwab Government Money Fund - Investor Shares | 31 to 60 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 3.30%
Schwab Government Money Fund - Investor Shares | 61 to 90 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 1.10%
Schwab Government Money Fund - Investor Shares | 91 to 180 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 1.60%
Schwab Government Money Fund - Investor Shares | Over 180 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 10.20%
Schwab Government Money Fund - Investor Shares | Repurchase Agreements [Member]  
Holdings [Line Items]  
Percent of Total Investments 62.20%
Schwab Government Money Fund - Investor Shares | Repurchase Agreements U.S. Government Agency [Member]  
Holdings [Line Items]  
Percent of Total Investments 37.00%
Schwab Government Money Fund - Investor Shares | Repurchase Agreements U.S. Treasury [Member]  
Holdings [Line Items]  
Percent of Total Investments 25.20%
Schwab Government Money Fund - Investor Shares | U.S. Government Agency Debt [Member]  
Holdings [Line Items]  
Percent of Total Investments 31.40%
Schwab Government Money Fund - Investor Shares | U.S. Treasury Debt [Member]  
Holdings [Line Items]  
Percent of Total Investments 6.20%
Schwab Government Money Fund - Investor Shares | Variable Rate Demand Notes [Member]  
Holdings [Line Items]  
Percent of Total Investments 0.20%
Schwab Government Money Fund - Ultra Shares | 1 to 7 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 82.80%
Schwab Government Money Fund - Ultra Shares | 8 to 30 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 1.00%
Schwab Government Money Fund - Ultra Shares | 31 to 60 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 3.30%
Schwab Government Money Fund - Ultra Shares | 61 to 90 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 1.10%
Schwab Government Money Fund - Ultra Shares | 91 to 180 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 1.60%
Schwab Government Money Fund - Ultra Shares | Over 180 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 10.20%
Schwab Government Money Fund - Ultra Shares | Repurchase Agreements [Member]  
Holdings [Line Items]  
Percent of Total Investments 62.20%
Schwab Government Money Fund - Ultra Shares | Repurchase Agreements U.S. Government Agency [Member]  
Holdings [Line Items]  
Percent of Total Investments 37.00%
Schwab Government Money Fund - Ultra Shares | Repurchase Agreements U.S. Treasury [Member]  
Holdings [Line Items]  
Percent of Total Investments 25.20%
Schwab Government Money Fund - Ultra Shares | U.S. Government Agency Debt [Member]  
Holdings [Line Items]  
Percent of Total Investments 31.40%
Schwab Government Money Fund - Ultra Shares | U.S. Treasury Debt [Member]  
Holdings [Line Items]  
Percent of Total Investments 6.20%
Schwab Government Money Fund - Ultra Shares | Variable Rate Demand Notes [Member]  
Holdings [Line Items]  
Percent of Total Investments 0.20%
Schwab U.S. Treasury Money Fund - Investor Shares | 1 to 7 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 29.60%
Schwab U.S. Treasury Money Fund - Investor Shares | 8 to 30 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 59.80%
Schwab U.S. Treasury Money Fund - Investor Shares | 91 to 180 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 1.50%
Schwab U.S. Treasury Money Fund - Investor Shares | Over 180 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 9.10%
Schwab U.S. Treasury Money Fund - Investor Shares | U.S. Treasury Debt [Member]  
Holdings [Line Items]  
Percent of Total Investments 100.00%
Schwab U.S. Treasury Money Fund - Ultra Shares | 1 to 7 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 29.60%
Schwab U.S. Treasury Money Fund - Ultra Shares | 8 to 30 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 59.80%
Schwab U.S. Treasury Money Fund - Ultra Shares | 91 to 180 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 1.50%
Schwab U.S. Treasury Money Fund - Ultra Shares | Over 180 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 9.10%
Schwab U.S. Treasury Money Fund - Ultra Shares | U.S. Treasury Debt [Member]  
Holdings [Line Items]  
Percent of Total Investments 100.00%
Schwab Treasury Obligations Money Fund - Investor Shares | 1 to 7 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 86.40%
Schwab Treasury Obligations Money Fund - Investor Shares | 31 to 60 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 1.00%
Schwab Treasury Obligations Money Fund - Investor Shares | 91 to 180 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 2.30%
Schwab Treasury Obligations Money Fund - Investor Shares | Over 180 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 10.30%
Schwab Treasury Obligations Money Fund - Investor Shares | Repurchase Agreements [Member]  
Holdings [Line Items]  
Percent of Total Investments 75.50%
Schwab Treasury Obligations Money Fund - Investor Shares | Repurchase Agreements U.S. Treasury [Member]  
Holdings [Line Items]  
Percent of Total Investments 75.50%
Schwab Treasury Obligations Money Fund - Investor Shares | U.S. Treasury Debt [Member]  
Holdings [Line Items]  
Percent of Total Investments 24.50%
Schwab Treasury Obligations Money Fund - Ultra Shares | 1 to 7 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 86.40%
Schwab Treasury Obligations Money Fund - Ultra Shares | 31 to 60 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 1.00%
Schwab Treasury Obligations Money Fund - Ultra Shares | 91 to 180 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 2.30%
Schwab Treasury Obligations Money Fund - Ultra Shares | Over 180 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 10.30%
Schwab Treasury Obligations Money Fund - Ultra Shares | Repurchase Agreements [Member]  
Holdings [Line Items]  
Percent of Total Investments 75.50%
Schwab Treasury Obligations Money Fund - Ultra Shares | Repurchase Agreements U.S. Treasury [Member]  
Holdings [Line Items]  
Percent of Total Investments 75.50%
Schwab Treasury Obligations Money Fund - Ultra Shares | U.S. Treasury Debt [Member]  
Holdings [Line Items]  
Percent of Total Investments 24.50%
Schwab Municipal Money Fund - Investor Shares | 1 to 7 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 72.00%
Schwab Municipal Money Fund - Investor Shares | 8 to 30 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 5.90%
Schwab Municipal Money Fund - Investor Shares | 31 to 60 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 8.70%
Schwab Municipal Money Fund - Investor Shares | 61 to 90 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 2.50%
Schwab Municipal Money Fund - Investor Shares | 91 to 180 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 5.70%
Schwab Municipal Money Fund - Investor Shares | Over 180 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 5.20%
Schwab Municipal Money Fund - Investor Shares | FLORIDA  
Holdings [Line Items]  
Percent of Total Investments 4.50%
Schwab Municipal Money Fund - Investor Shares | GEORGIA  
Holdings [Line Items]  
Percent of Total Investments 4.10%
Schwab Municipal Money Fund - Investor Shares | TEXAS  
Holdings [Line Items]  
Percent of Total Investments 19.70%
Schwab Municipal Money Fund - Investor Shares | NEW YORK  
Holdings [Line Items]  
Percent of Total Investments 13.10%
Schwab Municipal Money Fund - Investor Shares | MASSACHUSETTS  
Holdings [Line Items]  
Percent of Total Investments 4.20%
Schwab Municipal Money Fund - Investor Shares | Tender Option Bonds [Member]  
Holdings [Line Items]  
Percent of Total Investments 17.40%
Schwab Municipal Money Fund - Investor Shares | Variable Rate Demand Obligation [Member]  
Holdings [Line Items]  
Percent of Total Investments 40.40%
Schwab Municipal Money Fund - Investor Shares | Fixed Rate Notes [Member]  
Holdings [Line Items]  
Percent of Total Investments 8.90%
Schwab Municipal Money Fund - Investor Shares | Variable Rate Demand Preferred Shares [Member]  
Holdings [Line Items]  
Percent of Total Investments 10.70%
Schwab Municipal Money Fund - Investor Shares | Commercial Paper [Member]  
Holdings [Line Items]  
Percent of Total Investments 21.80%
Schwab Municipal Money Fund - Investor Shares | Put Bonds [Member]  
Holdings [Line Items]  
Percent of Total Investments 0.80%
Schwab Municipal Money Fund - Ultra Shares | 1 to 7 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 72.00%
Schwab Municipal Money Fund - Ultra Shares | 8 to 30 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 5.90%
Schwab Municipal Money Fund - Ultra Shares | 31 to 60 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 8.70%
Schwab Municipal Money Fund - Ultra Shares | 61 to 90 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 2.50%
Schwab Municipal Money Fund - Ultra Shares | 91 to 180 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 5.70%
Schwab Municipal Money Fund - Ultra Shares | Over 180 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 5.20%
Schwab Municipal Money Fund - Ultra Shares | FLORIDA  
Holdings [Line Items]  
Percent of Total Investments 4.50%
Schwab Municipal Money Fund - Ultra Shares | GEORGIA  
Holdings [Line Items]  
Percent of Total Investments 4.10%
Schwab Municipal Money Fund - Ultra Shares | TEXAS  
Holdings [Line Items]  
Percent of Total Investments 19.70%
Schwab Municipal Money Fund - Ultra Shares | NEW YORK  
Holdings [Line Items]  
Percent of Total Investments 13.10%
Schwab Municipal Money Fund - Ultra Shares | MASSACHUSETTS  
Holdings [Line Items]  
Percent of Total Investments 4.20%
Schwab Municipal Money Fund - Ultra Shares | Tender Option Bonds [Member]  
Holdings [Line Items]  
Percent of Total Investments 17.40%
Schwab Municipal Money Fund - Ultra Shares | Variable Rate Demand Obligation [Member]  
Holdings [Line Items]  
Percent of Total Investments 40.40%
Schwab Municipal Money Fund - Ultra Shares | Fixed Rate Notes [Member]  
Holdings [Line Items]  
Percent of Total Investments 8.90%
Schwab Municipal Money Fund - Ultra Shares | Variable Rate Demand Preferred Shares [Member]  
Holdings [Line Items]  
Percent of Total Investments 10.70%
Schwab Municipal Money Fund - Ultra Shares | Commercial Paper [Member]  
Holdings [Line Items]  
Percent of Total Investments 21.80%
Schwab Municipal Money Fund - Ultra Shares | Put Bonds [Member]  
Holdings [Line Items]  
Percent of Total Investments 0.80%
Schwab AMT Tax-Free Money Fund - Investor Shares | 1 to 7 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 68.10%
Schwab AMT Tax-Free Money Fund - Investor Shares | 8 to 30 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 11.00%
Schwab AMT Tax-Free Money Fund - Investor Shares | 31 to 60 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 7.00%
Schwab AMT Tax-Free Money Fund - Investor Shares | 61 to 90 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 2.80%
Schwab AMT Tax-Free Money Fund - Investor Shares | 91 to 180 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 6.40%
Schwab AMT Tax-Free Money Fund - Investor Shares | Over 180 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 4.70%
Schwab AMT Tax-Free Money Fund - Investor Shares | TEXAS  
Holdings [Line Items]  
Percent of Total Investments 21.20%
Schwab AMT Tax-Free Money Fund - Investor Shares | NEW YORK  
Holdings [Line Items]  
Percent of Total Investments 11.90%
Schwab AMT Tax-Free Money Fund - Investor Shares | MASSACHUSETTS  
Holdings [Line Items]  
Percent of Total Investments 7.30%
Schwab AMT Tax-Free Money Fund - Investor Shares | ALABAMA  
Holdings [Line Items]  
Percent of Total Investments 5.30%
Schwab AMT Tax-Free Money Fund - Investor Shares | PENNSYLVANIA  
Holdings [Line Items]  
Percent of Total Investments 4.40%
Schwab AMT Tax-Free Money Fund - Investor Shares | Tender Option Bonds [Member]  
Holdings [Line Items]  
Percent of Total Investments 31.10%
Schwab AMT Tax-Free Money Fund - Investor Shares | Variable Rate Demand Obligation [Member]  
Holdings [Line Items]  
Percent of Total Investments 22.30%
Schwab AMT Tax-Free Money Fund - Investor Shares | Fixed Rate Notes [Member]  
Holdings [Line Items]  
Percent of Total Investments 9.00%
Schwab AMT Tax-Free Money Fund - Investor Shares | Variable Rate Demand Preferred Shares [Member]  
Holdings [Line Items]  
Percent of Total Investments 10.50%
Schwab AMT Tax-Free Money Fund - Investor Shares | Commercial Paper [Member]  
Holdings [Line Items]  
Percent of Total Investments 26.20%
Schwab AMT Tax-Free Money Fund - Investor Shares | Put Bonds [Member]  
Holdings [Line Items]  
Percent of Total Investments 0.90%
Schwab AMT Tax-Free Money Fund - Ultra Shares | 1 to 7 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 68.10%
Schwab AMT Tax-Free Money Fund - Ultra Shares | 8 to 30 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 11.00%
Schwab AMT Tax-Free Money Fund - Ultra Shares | 31 to 60 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 7.00%
Schwab AMT Tax-Free Money Fund - Ultra Shares | 61 to 90 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 2.80%
Schwab AMT Tax-Free Money Fund - Ultra Shares | 91 to 180 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 6.40%
Schwab AMT Tax-Free Money Fund - Ultra Shares | Over 180 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 4.70%
Schwab AMT Tax-Free Money Fund - Ultra Shares | TEXAS  
Holdings [Line Items]  
Percent of Total Investments 21.20%
Schwab AMT Tax-Free Money Fund - Ultra Shares | NEW YORK  
Holdings [Line Items]  
Percent of Total Investments 11.90%
Schwab AMT Tax-Free Money Fund - Ultra Shares | MASSACHUSETTS  
Holdings [Line Items]  
Percent of Total Investments 7.30%
Schwab AMT Tax-Free Money Fund - Ultra Shares | ALABAMA  
Holdings [Line Items]  
Percent of Total Investments 5.30%
Schwab AMT Tax-Free Money Fund - Ultra Shares | PENNSYLVANIA  
Holdings [Line Items]  
Percent of Total Investments 4.40%
Schwab AMT Tax-Free Money Fund - Ultra Shares | Tender Option Bonds [Member]  
Holdings [Line Items]  
Percent of Total Investments 31.10%
Schwab AMT Tax-Free Money Fund - Ultra Shares | Variable Rate Demand Obligation [Member]  
Holdings [Line Items]  
Percent of Total Investments 22.30%
Schwab AMT Tax-Free Money Fund - Ultra Shares | Fixed Rate Notes [Member]  
Holdings [Line Items]  
Percent of Total Investments 9.00%
Schwab AMT Tax-Free Money Fund - Ultra Shares | Variable Rate Demand Preferred Shares [Member]  
Holdings [Line Items]  
Percent of Total Investments 10.50%
Schwab AMT Tax-Free Money Fund - Ultra Shares | Commercial Paper [Member]  
Holdings [Line Items]  
Percent of Total Investments 26.20%
Schwab AMT Tax-Free Money Fund - Ultra Shares | Put Bonds [Member]  
Holdings [Line Items]  
Percent of Total Investments 0.90%
Schwab California Municipal Money Fund - Investor Shares | 1 to 7 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 62.90%
Schwab California Municipal Money Fund - Investor Shares | 8 to 30 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 8.30%
Schwab California Municipal Money Fund - Investor Shares | 31 to 60 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 13.60%
Schwab California Municipal Money Fund - Investor Shares | 61 to 90 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 5.50%
Schwab California Municipal Money Fund - Investor Shares | 91 to 180 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 6.10%
Schwab California Municipal Money Fund - Investor Shares | Over 180 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 3.60%
Schwab California Municipal Money Fund - Investor Shares | Tender Option Bonds [Member]  
Holdings [Line Items]  
Percent of Total Investments 11.00%
Schwab California Municipal Money Fund - Investor Shares | Variable Rate Demand Obligation [Member]  
Holdings [Line Items]  
Percent of Total Investments 42.20%
Schwab California Municipal Money Fund - Investor Shares | Fixed Rate Notes [Member]  
Holdings [Line Items]  
Percent of Total Investments 6.60%
Schwab California Municipal Money Fund - Investor Shares | Variable Rate Demand Preferred Shares [Member]  
Holdings [Line Items]  
Percent of Total Investments 7.10%
Schwab California Municipal Money Fund - Investor Shares | Commercial Paper [Member]  
Holdings [Line Items]  
Percent of Total Investments 33.10%
Schwab California Municipal Money Fund - Ultra Shares | 1 to 7 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 62.90%
Schwab California Municipal Money Fund - Ultra Shares | 8 to 30 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 8.30%
Schwab California Municipal Money Fund - Ultra Shares | 31 to 60 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 13.60%
Schwab California Municipal Money Fund - Ultra Shares | 61 to 90 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 5.50%
Schwab California Municipal Money Fund - Ultra Shares | 91 to 180 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 6.10%
Schwab California Municipal Money Fund - Ultra Shares | Over 180 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 3.60%
Schwab California Municipal Money Fund - Ultra Shares | Tender Option Bonds [Member]  
Holdings [Line Items]  
Percent of Total Investments 11.00%
Schwab California Municipal Money Fund - Ultra Shares | Variable Rate Demand Obligation [Member]  
Holdings [Line Items]  
Percent of Total Investments 42.20%
Schwab California Municipal Money Fund - Ultra Shares | Fixed Rate Notes [Member]  
Holdings [Line Items]  
Percent of Total Investments 6.60%
Schwab California Municipal Money Fund - Ultra Shares | Variable Rate Demand Preferred Shares [Member]  
Holdings [Line Items]  
Percent of Total Investments 7.10%
Schwab California Municipal Money Fund - Ultra Shares | Commercial Paper [Member]  
Holdings [Line Items]  
Percent of Total Investments 33.10%
Schwab New York Municipal Money Fund - Investor Shares | 1 to 7 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 82.30%
Schwab New York Municipal Money Fund - Investor Shares | 8 to 30 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 4.30%
Schwab New York Municipal Money Fund - Investor Shares | 31 to 60 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 3.80%
Schwab New York Municipal Money Fund - Investor Shares | 61 to 90 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 0.70%
Schwab New York Municipal Money Fund - Investor Shares | 91 to 180 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 2.70%
Schwab New York Municipal Money Fund - Investor Shares | Over 180 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 6.20%
Schwab New York Municipal Money Fund - Investor Shares | Tender Option Bonds [Member]  
Holdings [Line Items]  
Percent of Total Investments 37.60%
Schwab New York Municipal Money Fund - Investor Shares | Variable Rate Demand Obligation [Member]  
Holdings [Line Items]  
Percent of Total Investments 34.00%
Schwab New York Municipal Money Fund - Investor Shares | Fixed Rate Notes [Member]  
Holdings [Line Items]  
Percent of Total Investments 12.30%
Schwab New York Municipal Money Fund - Investor Shares | Variable Rate Demand Preferred Shares [Member]  
Holdings [Line Items]  
Percent of Total Investments 9.20%
Schwab New York Municipal Money Fund - Investor Shares | Commercial Paper [Member]  
Holdings [Line Items]  
Percent of Total Investments 4.10%
Schwab New York Municipal Money Fund - Investor Shares | Put Bonds [Member]  
Holdings [Line Items]  
Percent of Total Investments 2.80%
Schwab New York Municipal Money Fund - Ultra Shares | 1 to 7 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 82.30%
Schwab New York Municipal Money Fund - Ultra Shares | 8 to 30 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 4.30%
Schwab New York Municipal Money Fund - Ultra Shares | 31 to 60 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 3.80%
Schwab New York Municipal Money Fund - Ultra Shares | 61 to 90 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 0.70%
Schwab New York Municipal Money Fund - Ultra Shares | 91 to 180 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 2.70%
Schwab New York Municipal Money Fund - Ultra Shares | Over 180 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 6.20%
Schwab New York Municipal Money Fund - Ultra Shares | Tender Option Bonds [Member]  
Holdings [Line Items]  
Percent of Total Investments 37.60%
Schwab New York Municipal Money Fund - Ultra Shares | Variable Rate Demand Obligation [Member]  
Holdings [Line Items]  
Percent of Total Investments 34.00%
Schwab New York Municipal Money Fund - Ultra Shares | Fixed Rate Notes [Member]  
Holdings [Line Items]  
Percent of Total Investments 12.30%
Schwab New York Municipal Money Fund - Ultra Shares | Variable Rate Demand Preferred Shares [Member]  
Holdings [Line Items]  
Percent of Total Investments 9.20%
Schwab New York Municipal Money Fund - Ultra Shares | Commercial Paper [Member]  
Holdings [Line Items]  
Percent of Total Investments 4.10%
Schwab New York Municipal Money Fund - Ultra Shares | Put Bonds [Member]  
Holdings [Line Items]  
Percent of Total Investments 2.80%
Schwab Retirement Government Money Fund | 1 to 7 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 83.50%
Schwab Retirement Government Money Fund | 8 to 30 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 1.00%
Schwab Retirement Government Money Fund | 31 to 60 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 2.60%
Schwab Retirement Government Money Fund | 61 to 90 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 1.10%
Schwab Retirement Government Money Fund | 91 to 180 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 1.70%
Schwab Retirement Government Money Fund | Over 180 Days [Member]  
Holdings [Line Items]  
Percent of Total Investments 10.10%
Schwab Retirement Government Money Fund | Repurchase Agreements [Member]  
Holdings [Line Items]  
Percent of Total Investments 64.00%
Schwab Retirement Government Money Fund | Repurchase Agreements U.S. Government Agency [Member]  
Holdings [Line Items]  
Percent of Total Investments 36.70%
Schwab Retirement Government Money Fund | Repurchase Agreements U.S. Treasury [Member]  
Holdings [Line Items]  
Percent of Total Investments 27.30%
Schwab Retirement Government Money Fund | U.S. Government Agency Debt [Member]  
Holdings [Line Items]  
Percent of Total Investments 29.60%
Schwab Retirement Government Money Fund | U.S. Treasury Debt [Member]  
Holdings [Line Items]  
Percent of Total Investments 6.10%
Schwab Retirement Government Money Fund | Variable Rate Demand Notes [Member]  
Holdings [Line Items]  
Percent of Total Investments 0.30%