Additional amount by which the credit facility can be increased.

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Maximum Ratio Of Debt To Capitalization

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Carrying value as of the balance sheet date of short-term borrowings using unsecured obligations issued by banks, corporations and other borrowers to investors. The maturities of these money market securities generally do not exceed 270 days.

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

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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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Amount, after accumulated amortization, of debt discount.

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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No definition available.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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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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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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Debt and Financing Arrangements (Details) - USD ($)	Dec. 31, 2023	Dec. 31, 2022	Oct. 08, 2021	Jul. 13, 2018
Debt Instrument [Line Items]
Long-term Debt	$ 581,178,000	$ 580,083,000
Issuance of debt	1,954,000	2,517,000
Debt Instrument, Unamortized Discount	1,868,000	2,400,000
Long-term Debt, Fiscal Year Maturity [Abstract]
2025	85,000,000
2027	500,000,000
7.125 percent unsecured debentures due 2025 [Member]
Debt Instrument [Line Items]
Long-term Debt	$ 85,000,000	85,000,000
Debt Instrument, Interest Rate, Stated Percentage	7.125%
4.0% unsecured debentures due 2027 [Member]
Debt Instrument [Line Items]
Long-term Debt	$ 500,000,000	$ 500,000,000
Debt Instrument, Interest Rate, Stated Percentage	4.00%
Asset Pledged as Collateral [Member]
Debt Instrument [Line Items]
Long-term Debt	$ 0
Line of Credit [Member]
Credit Facility and Commercial Paper [Line Items]
Credit Facility Capacity			$ 500,000,000
Williams Companies Inc [Member]
Credit Facility and Commercial Paper [Line Items]
Commercial Paper Outstanding	725,000,000
Williams Companies Inc [Member] \| Commercial Paper Program
Credit Facility and Commercial Paper [Line Items]
Credit Facility Capacity			3,500,000,000
Williams Companies Inc [Member] \| Swing Line Loan
Credit Facility and Commercial Paper [Line Items]
Credit Facility Capacity			200,000,000
Williams Companies Inc [Member] \| Line of Credit [Member]
Credit Facility and Commercial Paper [Line Items]
Credit Facility Capacity			3,750,000,000	$ 4,500,000,000
Additional Amount By Which Credit Facility Can Be Increased			$ 500,000,000
Loans Outstanding	0
Williams Companies Inc [Member] \| Letter of Credit Commitments
Credit Facility and Commercial Paper [Line Items]
Credit Facility Capacity				$ 500,000,000
Letters of Credit Outstanding, Amount	$ 0
Transco [Member]
Credit Facility and Commercial Paper [Line Items]
Maximum Ratio Of Debt To Capitalization	65.00%
Northwest [Member]
Credit Facility and Commercial Paper [Line Items]
Maximum Ratio Of Debt To Capitalization	65.00%