XML 61 R50.htm IDEA: XBRL DOCUMENT v3.21.2

Commitments and Contingencies (Details) $ in Millions	9 Months Ended
	Sep. 30, 2021 USD ($)
Pending Litigation | Westmoreland Arbitration
Other Commitments [Line Items]
Recovery sought	$ 5.5
Otter Tail Power Company | Coyote Station
Other Commitments [Line Items]
Ownership percentage	35.00%
Otter Tail Power Company | Federal Energy Regulatory Commission
Other Commitments [Line Items]
Estimated liability of refund obligation	$ 3.0

X

- Definition

This element represents amount of estimated liability for FERC ordered MISO tariff ROE refund obligation.

+ References

No definition available.

+ Details

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

X

- Definition

The proportionate share of interest (percent) in a jointly owned utility plant.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 980
-SubTopic 360
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 10.C)
-URI http://asc.fasb.org/extlink&oid=122136288&loc=d3e659983-123033

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Balance Type:	na
Period Type:	instant

X

- Definition

The value (monetary amount) of the award the plaintiff seeks in the legal matter.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 9
-Subparagraph (a)
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Section 50
-Paragraph 4
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-Publisher FASB
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-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=121557415&loc=d3e14326-108349

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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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- Details

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- Details

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X

- Details

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- Details

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