Risk Management and Derivatives: Cash Flow Hedges (Details) - Cash Flow Hedging - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Interest rate swaps
Derivative [Line Items]
Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months	$ 5.5
Designated as Hedging Instrument
Derivative [Line Items]
Unrealized Gain Losses On Cash Flow Hedging Instruments	0.5	$ 5.8	$ 1.3
Derivative Instruments Gain Losses Reclassified From Accumulated OCI Into Income Effective Portion Net	(3.9)	(6.4)	(5.9)
Designated as Hedging Instrument \| Interest rate swaps
Derivative [Line Items]
Unrealized Gain Losses On Cash Flow Hedging Instruments	2.9	2.9	2.9
Derivative Instruments Losses Reclassified from Accumulated OCI Into Income Effective Portion	(2.9)	(2.9)	(2.9)
Designated as Hedging Instrument \| Commodity Contract
Derivative [Line Items]
Unrealized Gain Losses On Cash Flow Hedging Instruments	(2.4)	2.9	(1.6)
Derivative Instruments Losses Reclassified from Accumulated OCI Into Income Effective Portion	$ (1.0)	$ (3.5)	$ (3.0)

Derivative instruments gain losses reclassified from accumulated OCI into income effective portion net.

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- Definition

Derivative instruments losses reclassified from accumulated OCI into income effective portion.

+ References

No definition available.

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- Definition

Unrealized gain losses on cash flow hedging instruments.

+ References

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- Definition

The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480870/815-30-50-1

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- 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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 20
-Name Accounting Standards Codification
-Section 25
-Paragraph 6A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480682/815-20-25-6A

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480237/815-40-50-5

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