Expense Example (Money Market Trust B, Series NAV, Money Market Trust B, USD $)	12 Months Ended
May 01, 2011
Money Market Trust B \| Series NAV, Money Market Trust B
Expense Example:
Year 1	$ 29
Year 3	145
Year 5	271
Year 10	$ 641

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The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.

+ References

Reference 1: 1
-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 3
-Paragraph 4
-Subsection instructions

+ Details

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- Definition

+ References

Reference 1: 1
-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 3
-Paragraph 1
-Subparagraph 2
-Subsection example

+ Details

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Namespace Prefix:	rr
Data Type:	rr:NonNegativeMonetaryType
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Period Type:	duration

- Definition

+ References

Reference 1: 1
-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 3
-Paragraph 1
-Subparagraph 2
-Subsection example

+ Details

Name:	rr_ExpenseExampleYear05
Namespace Prefix:	rr
Data Type:	rr:NonNegativeMonetaryType
Balance Type:	na
Period Type:	duration

- Definition

+ References

Reference 1: 1
-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 3
-Paragraph 1
-Subparagraph 2
-Subsection example

+ Details

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Data Type:	rr:NonNegativeMonetaryType
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Period Type:	duration