v2.4.1.9

FAIR VALUE (Schedule of Assets and Liabilities Measured at Fair Value on a Recurring Basis) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Investments
Corporate bonds	$ 44,853ipi_Fairvalueassetsmeasuredonrecurringbasiscorporatebonds	$ 21,288ipi_Fairvalueassetsmeasuredonrecurringbasiscorporatebonds
Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1)
Investments
Corporate bonds	0ipi_Fairvalueassetsmeasuredonrecurringbasiscorporatebonds / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member	0ipi_Fairvalueassetsmeasuredonrecurringbasiscorporatebonds / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member
Significant Observable Inputs (Level 2)
Investments
Corporate bonds	44,853ipi_Fairvalueassetsmeasuredonrecurringbasiscorporatebonds / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member	21,288ipi_Fairvalueassetsmeasuredonrecurringbasiscorporatebonds / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member
Significant Unobservable Inputs (Level 3)
Investments
Corporate bonds	$ 0ipi_Fairvalueassetsmeasuredonrecurringbasiscorporatebonds / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member	$ 0ipi_Fairvalueassetsmeasuredonrecurringbasiscorporatebonds / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member

X

- Definition

This element represents a certain statement of financial position asset caption which represents a class of assets , or which may include an individual asset, measured at fair value on a recurring basis.

+ References

No definition available.

+ Details

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Balance Type:	debit
Period Type:	instant

X

- Details

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- Details

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X

- Details

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X

- Details

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