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Fair Value Measurement (Narrative) (Details) | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2012 transfers | Jun. 30, 2011 transfers | Jun. 30, 2012
Fair Value Measurement [Line Items] |  |  |
Percentage of portfolio of unadjusted fair values obtained |  |  | 97.00%
Percentage of portfolio of specific unadjusted broker quotes obtained |  |  | 3.00%
Transfers between Levels 1, 2, and 3 of the fair value hierarchy | 0 | 0 |
Minimum [Member] |  |  |
Fair Value Measurement [Line Items] |  |  |
Number of knowledgeable outside security brokers consulted to determine fair value |  |  | 1

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- Definition Percentage of specific unadjusted broker quotes obtained + References No definition available. + Details
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