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Property, Plant and Equipment (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Property, Plant and Equipment [Line Items]
Depreciation	$ 756.9	$ 685.0	$ 672.1
Regulatory Deferral - Joint Venture	12.5	11.0	5.3
Capitalized Computer Software, Amortization	77.5	53.1	49.4
Capitalized Computer Software, Gross	205.6	190.1
Capitalized Cloud Computing, Amortization	12.6	11.1	$ 10.0
Capitalized Cloud Computing, Gross	$ 32.2	$ 45.7

X

- Definition

Capitalized Cloud Computing, Amortization

+ References

No definition available.

+ Details

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- Definition

Capitalized Cloud Computing, Gross

+ References

No definition available.

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X

- Definition

Regulatory Deferral - Joint Venture

+ References

No definition available.

+ Details

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X

- Definition

Amount of expense for amortization of capitalized computer software costs.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 985
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481283/985-20-50-2

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (b)(1)
-SubTopic 20
-Topic 985
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481283/985-20-50-1

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X

- Definition

Amount before accumulated amortization of capitalized costs for computer software, including but not limited to, acquired and internally developed computer software.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 985
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481283/985-20-50-1

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- Definition

The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Subparagraph (b)
-SubTopic 10
-Topic 230
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482740/230-10-45-28

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482099/360-10-50-1

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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

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