Vanguard Extended Duration Treasury Index Fund Annual Total Returns |
12 Months Ended | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
Dec. 31, 2024 |
Dec. 31, 2023 |
Dec. 31, 2022 |
Dec. 31, 2021 |
Dec. 31, 2020 |
Dec. 31, 2019 |
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
|
| ETF Prospectus [Member] | Vanguard Extended Duration Treasury Index Fund | ETF Shares | ||||||||||
| Prospectus [Line Items] | ||||||||||
| Annual Return [Percent] | (13.27%) | 2.14% | (39.40%) | (6.52%) | 24.22% | 19.14% | (3.51%) | 13.52% | 1.52% | (4.45%) |