Receivables (Narrative) (Details) - Receivables Sold [Member] - IPL [Member] $ in Millions	Sep. 30, 2019 USD ($)
Receivables [Line Items]
Available capacity	$ 109.0
Outstanding receivables past due	$ 26.6

Amount of financing receivable past due.

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant