No definition available.

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Represents the maximum borrowings available for the commercial paper program under the terms of line of credit facility.

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No definition available.

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Represents the number of line of credit facilities.

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No definition available.

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Line of Credit Facility, Additional Capacity Increase Available

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No definition available.

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Represents the percentage of capitalization which is used to calculate the short-term debt authorization pursuant to an order from a regulatory authority.

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No definition available.

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Represents the fixed amount required to be used for purchases of natural gas and power which is used to calculate the short-term debt authorization pursuant to an order from a regulatory authority.

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No definition available.

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

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No definition available.

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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.

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No definition available.

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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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Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

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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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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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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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No definition available.

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Lines of Credit and Short-Term Borrowings (Details)	Jun. 28, 2018 USD ($)	Jun. 27, 2018 USD ($)	Dec. 31, 2018 USD ($) Facility	Nov. 27, 2018 USD ($)	Jul. 12, 2018 USD ($)	Jul. 11, 2018 USD ($)	Dec. 31, 2017 USD ($)
Lines of Credit and Short-Term Borrowings
Short-term borrowings			$ 76,400,000				$ 95,400,000
Pinnacle West
Lines of Credit and Short-Term Borrowings
Short-term borrowings			76,400,000				95,400,000
ARIZONA PUBLIC SERVICE COMPANY \| ACC
Debt Provisions
Percentage of APS's capitalization used in calculation of short-term debt authorization				7.00%
Required amount to be used in purchases of natural gas and power which is used in calculation of short-term debt authorization				$ 500,000,000
Revolving credit facility
Lines of Credit and Short-Term Borrowings
Amount committed			1,350,000,000				1,325,000,000
Long-term line of credit			76,400,000				95,400,000
Revolving credit facility \| Pinnacle West
Lines of Credit and Short-Term Borrowings
Amount committed			350,000,000				325,000,000
Long-term line of credit			76,400,000				95,400,000
Revolving credit facility \| Pinnacle West \| Revolving credit facility maturing July 2018
Lines of Credit and Short-Term Borrowings
Maximum borrowing capacity on credit facility upon satisfaction of certain conditions and consent of lenders		$ 125,000,000
Debt instrument, term		364 days
Revolving credit facility \| Pinnacle West \| Revolving Credit Facility Maturing June 2019 [Member]
Lines of Credit and Short-Term Borrowings
Maximum borrowing capacity on credit facility upon satisfaction of certain conditions and consent of lenders	$ 150,000,000
Debt instrument, term	364 days
Short-term borrowings			54,000,000
Revolving credit facility \| Pinnacle West \| Revolving credit facility maturing May 2021
Lines of Credit and Short-Term Borrowings
Amount committed						$ 200,000,000
Revolving credit facility \| Pinnacle West \| Revolving credit facility maturing July 2023
Lines of Credit and Short-Term Borrowings
Amount committed					$ 200,000,000
Maximum borrowing capacity on credit facility upon satisfaction of certain conditions and consent of lenders			300,000,000
Long-term line of credit			0
Revolving credit facility \| ARIZONA PUBLIC SERVICE COMPANY
Lines of Credit and Short-Term Borrowings
Amount committed			1,000,000,000				1,000,000,000
Long-term line of credit			0				$ 0
Revolving credit facility \| ARIZONA PUBLIC SERVICE COMPANY \| Revolving credit facility maturing June 2022
Lines of Credit and Short-Term Borrowings
Amount committed			500,000,000
Revolving credit facility \| ARIZONA PUBLIC SERVICE COMPANY \| Revolving credit facility maturing May 2021
Lines of Credit and Short-Term Borrowings
Amount committed						$ 500,000,000
Revolving credit facility \| ARIZONA PUBLIC SERVICE COMPANY \| Revolving credit facility maturing July 2023
Lines of Credit and Short-Term Borrowings
Amount committed			500,000,000		$ 500,000,000
Revolving credit facility \| ARIZONA PUBLIC SERVICE COMPANY \| Revolving Credit Facility Maturing in 2022 and 2023 [Member]
Lines of Credit and Short-Term Borrowings
Amount committed			1,000,000,000
Additional capacity increase available			700,000,000
Maximum borrowing capacity on credit facility upon satisfaction of certain conditions and consent of lenders			1,400,000,000
Long-term line of credit			$ 0
Number of credit facilities \| Facility			2
Letter of credit \| Pinnacle West \| Revolving credit facility maturing July 2023
Lines of Credit and Short-Term Borrowings
Outstanding letters of credit			$ 0
Letter of credit \| ARIZONA PUBLIC SERVICE COMPANY
Lines of Credit and Short-Term Borrowings
Outstanding letters of credit			200,000
Commercial paper \| Pinnacle West \| Revolving credit facility maturing July 2023
Lines of Credit and Short-Term Borrowings
Commercial paper			22,000,000
Commercial paper \| ARIZONA PUBLIC SERVICE COMPANY
Lines of Credit and Short-Term Borrowings
Maximum commercial paper support available under credit facility			500,000,000
Commercial paper \| ARIZONA PUBLIC SERVICE COMPANY \| Revolving Credit Facility Maturing in 2022 and 2023 [Member]
Lines of Credit and Short-Term Borrowings
Long-term line of credit			$ 0
LIBOR \| Revolving credit facility \| Pinnacle West \| Revolving Credit Facility Maturing June 2019 [Member]
Lines of Credit and Short-Term Borrowings
Debt instrument, basis spread on variable rate		0.70%