Vanguard California Municipal Money Market Fund Average Annual Total Returns - Retail Prospectus [Member] |
12 Months Ended | 60 Months Ended | 120 Months Ended |
|---|---|---|---|
Dec. 31, 2025 |
Dec. 31, 2025 |
Dec. 31, 2025 |
|
| California Tax-Exempt Money Market Funds Average[Member] | |||
| Prospectus [Line Items] | |||
| Average Annual Return, Percent | 2.14% | 1.68% | 1.08% |
| Investor Shares | |||
| Prospectus [Line Items] | |||
| Average Annual Return, Percent | 2.17% | 1.70% | 1.23% |