Debt Instrument, Covenant, Ratio Of Funded Debt To Total Capitalization

No definition available.

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- Definition

Debt Instrument, Percentage Of Total With Interest Rates Reference To LIBOR And Due After 2021

+ References

No definition available.

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- Definition

Line Of Credit Facility, Amount Classified As Long-Term Debt

+ References

No definition available.

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- Definition

Line Of Credit Facility, Working Capital Purposes

+ References

No definition available.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

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- Definition

Amount of assets pledged to secure a debt instrument.

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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

No definition available.

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- Definition

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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- Definition

The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

+ References

No definition available.

+ Details

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- Definition

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.

+ References

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

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- Definition

Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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Debt - Additional Information (Detail)		3 Months Ended
Debt - Additional Information (Detail)	Apr. 10, 2020 USD ($)	Mar. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Nov. 30, 2018 USD ($)	Mar. 31, 2017 USD ($)
Debt Instrument [Line Items]
Short term borrowings outstanding		$ 157,000,000	$ 211,000,000
Percentage of total debt with interest rates reference to LIBOR and due after 2021		18.00%
Southwest Gas Corporation
Debt Instrument [Line Items]
Short term borrowings outstanding		$ 97,000,000	$ 194,000,000
Percentage of total debt with interest rates reference to LIBOR and due after 2021		11.00%
LIBOR \| Southwest Gas Corporation
Debt Instrument [Line Items]
Borrowings outstanding under facility		$ 247,000,000
LIBOR \| Centuri
Debt Instrument [Line Items]
Borrowings outstanding under facility		177,000,000
Commercial Paper Program \| Southwest Gas Corporation
Debt Instrument [Line Items]
Credit facility maximum borrowing capacity		50,000,000
Borrowings outstanding under facility		0
Secured Revolving Credit Facility and Term Loan \| Centuri
Debt Instrument [Line Items]
Credit facility maximum borrowing capacity				$ 590,000,000
Borrowings outstanding under facility		275,000,000
Debt secured by assets		1,200,000,000
Line of Credit \| Centuri
Debt Instrument [Line Items]
Credit facility maximum borrowing capacity				325,000,000
Centuri term loan facility \| Centuri
Debt Instrument [Line Items]
Credit facility maximum borrowing capacity				$ 265,000,000
Equipment Loans \| Centuri
Debt Instrument [Line Items]
Proceeds from debt		50,000,000
$400 Million Credit Facility \| Southwest Gas Corporation
Debt Instrument [Line Items]
Credit facility maximum borrowing capacity		400,000,000
Line of credit designated as long term debt		150,000,000
Line of credit designated for working capital purposes		250,000,000
Long-term debt		150,000,000
Short term borrowings outstanding		$ 97,000,000
$400 Million Credit Facility \| LIBOR \| Southwest Gas Corporation
Debt Instrument [Line Items]
Applicable margin		1.00%
$400 Million Credit Facility \| Alternative base rate \| Southwest Gas Corporation
Debt Instrument [Line Items]
Applicable margin		0.00%
$100 Million Credit Facility
Debt Instrument [Line Items]
Credit facility maximum borrowing capacity					$ 100,000,000
Short term borrowings outstanding		$ 60,000,000
Subsequent Event \| $400 Million Credit Facility \| Southwest Gas Corporation
Debt Instrument [Line Items]
Credit facility maximum borrowing capacity	$ 400,000,000
Debt covenant, ratio of funded debt to total capitalization	0.70
Subsequent Event \| $100 Million Credit Facility
Debt Instrument [Line Items]
Credit facility maximum borrowing capacity	$ 100,000,000
Debt covenant, ratio of funded debt to total capitalization	0.70
Subsequent Event \| Minimum \| $400 Million Credit Facility
Debt Instrument [Line Items]
Commitment fee percentage	0.075%
Subsequent Event \| Minimum \| $400 Million Credit Facility \| LIBOR
Debt Instrument [Line Items]
Applicable margin	0.75%
Subsequent Event \| Minimum \| $400 Million Credit Facility \| Alternative base rate
Debt Instrument [Line Items]
Applicable margin	0.00%
Subsequent Event \| Minimum \| $100 Million Credit Facility
Debt Instrument [Line Items]
Commitment fee percentage	0.075%
Subsequent Event \| Minimum \| $100 Million Credit Facility \| LIBOR
Debt Instrument [Line Items]
Applicable margin	0.75%
Subsequent Event \| Minimum \| $100 Million Credit Facility \| Alternative base rate
Debt Instrument [Line Items]
Applicable margin	0.00%
Subsequent Event \| Maximum \| $400 Million Credit Facility
Debt Instrument [Line Items]
Commitment fee percentage	0.20%
Subsequent Event \| Maximum \| $400 Million Credit Facility \| LIBOR
Debt Instrument [Line Items]
Applicable margin	1.50%
Subsequent Event \| Maximum \| $400 Million Credit Facility \| Alternative base rate
Debt Instrument [Line Items]
Applicable margin	0.50%
Subsequent Event \| Maximum \| $100 Million Credit Facility
Debt Instrument [Line Items]
Commitment fee percentage	0.20%
Subsequent Event \| Maximum \| $100 Million Credit Facility \| LIBOR
Debt Instrument [Line Items]
Applicable margin	1.50%
Subsequent Event \| Maximum \| $100 Million Credit Facility \| Alternative base rate
Debt Instrument [Line Items]
Applicable margin	0.50%