v2.3.0.15

ASSET RETIREMENT OBLIGATION (Details) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011 facility quarter Y segment	Sep. 30, 2010
ASSET RETIREMENT OBLIGATION
Credit adjusted risk-free rates to discount abandonment liabilities, low end of range (as a percent)	6.90%		6.90%
Credit adjusted risk-free rates to discount abandonment liabilities, high end of range (as a percent)	8.50%		8.50%
Changes to asset retirement obligations
Asset retirement obligation-beginning of period	$ 9,860,000	$ 8,981,000	$ 9,478,000	$ 8,619,000
Changes in estimated obligations	(287,000)		(287,000)	10,000
Accretion of discount	184,000	176,000	566,000	528,000
Total asset retirement obligation-end of period	9,757,000	9,157,000	9,757,000	9,157,000
Undiscounted amount of asset retirement obligation	$ 31,300,000		$ 31,300,000
Period in which no significant payments related to asset retirement obligation are expected (in years)			5

X

- Definition

Represents the high end of the range of the credit adjusted risk-free rate used to discount abandonment liabilities that are associated with an asset retirement obligation.

+ Details

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Balance Type:	na
Period Type:	instant

X

- Definition

Represents the low end of the range of the credit adjusted risk-free rate used to discount abandonment liabilities that are associated with an asset retirement obligation.

+ Details

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Namespace Prefix:	ipi
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

X

- Definition

The undiscounted amount of the asset retirement obligation.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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X

- Definition

Period in which no significant payments are expected to take place that are associated with an asset retirement obligation.

+ Details

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Data Type:	xbrli:integerItemType
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X

- Definition

The carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 143

-Paragraph 3, 10, 22

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 410

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849



Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Asset Retirement Obligation

-URI http://asc.fasb.org/extlink&oid=6505190

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X

- Definition

Amount of accretion expense recognized during the period that is associated with an asset retirement obligation. Accretion expense measures and incorporates changes due to the passage of time into the carrying amount of the liability.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 410

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (c)(3)

-URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 143

-Paragraph 13, 14

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.



Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 143

-Paragraph 22

-Subparagraph c(3)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.



Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 410

-SubTopic 20

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6392676&loc=d3e7480-110848

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X

- Definition

Amount of the Increase or Decrease in the amount of the asset retirement obligation during the current period for changes in the amount or timing of the estimated cash flows associated with the settlement of the obligation.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 143

-Paragraph 22

-Subparagraph c(4)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 410

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (c)(4)

-URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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