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Significant Accounting Policies - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Significant Accounting Policies [Line Items]
Estimated refunds	$ 25	$ 21
Amortization of contributions in aid of construction	$ 50	46	$ 40
Payment terms from billing, period	30 days
Alternative revenue programs, revenue, collection period	24 months
Cumulative gains losses as percentage of benefit obligations or plan assets	10.00%
Minimum reduction of expected future service of plan participants	10.00%
Maximum
Significant Accounting Policies [Line Items]
Payment terms from billing, period	1 year
Software
Significant Accounting Policies [Line Items]
Carrying value	$ 435	$ 398

X

- Definition

Alternative Revenue Programs, Revenue, Collection Period

+ References

No definition available.

+ Details

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X

- Definition

Amortization of contributions in aid of construction.

+ References

No definition available.

+ Details

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Period Type:	duration

X

- Definition

Contract with Customer, Payment Term From Billing, Period

+ References

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+ Details

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X

- Definition

Cumulative gains losses as percentage of benefit obligations or plan assets.

+ References

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X

- Definition

Reduction of expected future service of plan participants.

+ References

No definition available.

+ Details

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X

- Definition

Repayments of advances for construction expected to occur over the next 12 month period.

+ References

No definition available.

+ Details

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X

- Definition

Significant accounting policies.

+ References

No definition available.

+ Details

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X

- Definition

The carrying amount of capitalized computer software costs net of accumulated amortization as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 985
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481283/985-20-50-1

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Period Type:	instant

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- Details

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