Shareholder Fees (Vanguard Prime Money Market Fund Institutional)	Vanguard Prime Money Market Fund Vanguard Prime Money Market Fund - Institutional Shares 9/1/2013 - 8/31/2014
Shareholder Fees (fees paid directly from your investment]
Sales charge (load) imposed on purchases	none
Purchase Fee	none
Sales charge (load) imposed on reinvested dividends	none
Redemption Fee	none

Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price). If a sales charge (load) is imposed on shares purchased with reinvested capital gains distributions or returns of capital, include the bracketed words in the third caption.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

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-Chapter A

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- Definition

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Form

-Number N-1A

-Chapter A

-Section 3

-Subsection table

-Paragraph 1

-Subparagraph 1

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- Definition

Maximum Sales Charge (Load) Imposed on Reinvested Dividends[and other Distributions] (as a percentage of ____)

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Form

-Number N-1A

-Chapter A

-Section 3

-Subsection table

-Paragraph 1

-Subparagraph 3

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- Definition

"Redemption Fee" (as a percentage of amount redeemed, if applicable) If the Fund is an Exchange-Traded Fund and issues or redeems shares in creation units of not less than 25,000 shares each, exclude any fees charged for the purchase and redemption of the Fund's creation units. "Redemption Fee" includes a fee charged for any redemption of the Fund's shares, but does not include a deferred sales charge (load) imposed upon redemption.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Form

-Number N-1A

-Chapter A

-Section 3

-Subsection instructions

-Paragraph 2

-Subparagraph b

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