Expense Example (Ultra Short Term Bond Trust, USD $)	12 Months Ended
May 01, 2011
Series I, Ultra Short Term Bond Trust
Expense Example:
Year 1	$ 69
Year 3	218
Year 5	379
Year 10	847
Series II, Ultra Short Term Bond Trust
Expense Example:
Year 1	90
Year 3	281
Year 5	488
Year 10	1,084
Series NAV, Ultra Short Term Bond Trust
Expense Example:
Year 1	64
Year 3	202
Year 5	351
Year 10	$ 786

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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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- 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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- 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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