Gain (Loss) From Termination Of Derivative Instruments

No definition available.

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- Definition

Ineffectiveness Recognized on Hedge Instruments

+ References

No definition available.

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- Definition

The price per share of the conversion feature embedded in the debt instrument.

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- Definition

Ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount.

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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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.

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- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

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- Definition

The number of derivative instruments of a particular group held by the entity.

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- Definition

The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer.

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- Definition

Amount of cash outflow for short-term and long-term debt. Excludes payment of lease obligation.

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Long-Term Debt (Details)			1 Months Ended	3 Months Ended
Long-Term Debt (Details)	Feb. 27, 2025 USD ($)	Jun. 29, 2023 USD ($) $ / shares	Feb. 28, 2025 USD ($) treasuryLockAgreement	Mar. 31, 2025 USD ($) treasuryLockAgreement	Mar. 31, 2024 USD ($)	Dec. 31, 2024
Debt Instrument [Line Items]
Proceeds from long-term debt, net of discount				$ 810,000,000	$ 1,391,000,000
Treasury Lock Agreements \| Designated as Hedging Instrument
Debt Instrument [Line Items]
Debt instrument, face amount			$ 500,000,000	$ 130,000,000
Derivative, average fixed interest rate				4.12%
Derivative, number of instruments held \| treasuryLockAgreement			10	3
Debt instrument, term			10 years	30 years
Gain from termination of derivative instruments			$ 3,000,000
Ineffectiveness recognized on hedge instruments				$ 0	$ 0
Private activity bonds and government funded debt
Debt Instrument [Line Items]
Debt instrument, face amount				$ 13,000,000
Interest rate				0.00%
Various debt maturing in 2025 through 2061
Debt Instrument [Line Items]
Derivative, average fixed interest rate				3.41%
Repayments of debt				$ 531,000,000
Various debt maturing in 2025 through 2061 \| Minimum
Debt Instrument [Line Items]
Interest rate				0.00%
Various debt maturing in 2025 through 2061 \| Maximum
Debt Instrument [Line Items]
Interest rate				8.58%
American Water Capital Corp.
Debt Instrument [Line Items]
Derivative, average fixed interest rate				4.63%		4.65%
Senior note - fixed rate \| American Water Capital Corp.
Debt Instrument [Line Items]
Debt instrument, face amount	$ 800,000,000
Proceeds from long-term debt, net of discount	$ 792,000,000
Senior note - fixed rate \| American Water Capital Corp. \| Senior Note 5.250% Due 2035
Debt Instrument [Line Items]
Interest rate	5.25%
Senior note - fixed rate \| American Water Capital Corp. \| Senior Note 3.400% Due 2025
Debt Instrument [Line Items]
Interest rate	3.40%
Exchangeable Debt \| American Water Capital Corp. \| Exchangeable Senior Note 3.625% Due 2026
Debt Instrument [Line Items]
Debt instrument, face amount		$ 1,035,000,000
Interest rate		3.625%
Proceeds from long-term debt, net of discount		$ 1,022,000,000
Debt instrument, exchangeable, conversion ratio		0.0058213
Debt instrument, exchangeable, conversion price (dollars per share) \| $ / shares		$ 171.78
Debt instrument, redemption price, percentage		100.00%