v3.19.1

ASSET RETIREMENT OBLIGATION (Narrative) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2018 USD ($)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Undiscounted amount of asset retirement obligation	$ 59.5
Asset retirement obligation payments expected to be made	$ 6.6
Period in which no significant payments related to asset retirement obligation are expected (in years)	5 years
Measurement Input, Risk Free Interest Rate [Member] | Minimum [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Credit risk free rate	0.069
Measurement Input, Risk Free Interest Rate [Member] | Maximum [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Credit risk free rate	0.097

X

- Definition

Asset retirement obligation payments expected to be made in the next five years.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

X

- Definition

The undiscounted amount of the asset retirement obligation.

+ References

No definition available.

+ Details

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Namespace Prefix:	ipi_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

X

- Definition

Period in which payments are expected to take place that are associated with an asset retirement obligation.

+ References

No definition available.

+ Details

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Namespace Prefix:	ipi_
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Period Type:	duration

X

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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X

- Definition

Value of input used to measure long-term debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258

+ Details

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- Details

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- Details

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- Details

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