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Receivables (Narrative) (Details) (USD $) In Millions, unless otherwise specified			9 Months Ended
	Sep. 30, 2014 IPL [Member]	Dec. 31, 2013 IPL [Member]	Sep. 30, 2014 Whiting Petroleum Corporation [Member]
Receivables [Line Items]
Receivables sold	$ 203.7	$ 238.0
Final payment of certain future tax benefits expected to be realized			$ 26

X

- Definition

Receivables sold

+ References

No definition available.

+ Details

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X

- Definition

The cash inflow associated with the collection of other receivables not otherwise defined in the taxonomy.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 12

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3179-108585



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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

-URI http://asc.fasb.org/extlink&oid=6516133

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