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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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Represents the number of line of credit facilities.

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The common equity ratio (defined as the total shareholder equity divided by the sum of total shareholder equity and long-term debt, including current maturities of long-term debt), which the entity is required to maintain pursuant to an order from a regulatory authority.

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The amount of total shareholder equity required in order for the entity to pay dividends pursuant to an order from a regulatory authority.

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The sum of total shareholder equity and long-term debt less current maturities, including a portion of APS' current maturities of long-term debt.

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

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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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No definition available.

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Face (par) amount of the original debt instrument that was repurchased.

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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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The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

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No definition available.

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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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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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Long-Term Debt and Liquidity Matters - Narrative (Details)	Aug. 31, 2016 USD ($)	Aug. 01, 2016 USD ($)	Sep. 30, 2016 USD ($) Facility	Sep. 20, 2016 USD ($)	Jun. 01, 2016 USD ($)	May 13, 2016 USD ($)	May 12, 2016 USD ($)	May 06, 2016 USD ($)	Apr. 22, 2016 USD ($)	Mar. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Long-Term Debt and Liquidity Matters
Shot-term debt			$ 117,300,000								$ 0
Debt Provisions
Total shareholder equity			4,853,346,000								4,583,917,000
Pinnacle West \| Revolving Credit Facility \| Revolving credit facility maturing in May 2019
Long-Term Debt and Liquidity Matters
Current borrowing capacity on credit facility							$ 200,000,000
Pinnacle West \| Revolving Credit Facility \| Revolving credit facility maturing May 2021
Long-Term Debt and Liquidity Matters
Current borrowing capacity on credit facility						$ 200,000,000
Maximum borrowing capacity on credit facility upon satisfaction of certain conditions and consent of lenders (up to)			300,000,000
Outstanding borrowings			0
Pinnacle West \| Revolving Credit Facility \| Revolving credit facility maturing in August 2017
Long-Term Debt and Liquidity Matters
Maximum borrowing capacity on credit facility upon satisfaction of certain conditions and consent of lenders (up to)	$ 75,000,000
Debt instrument, term	364 days
Shot-term debt			34,000,000
Pinnacle West \| Letter of Credit \| Revolving credit facility maturing May 2021
Long-Term Debt and Liquidity Matters
Outstanding letters of credit			0
Pinnacle West \| Commercial paper \| Revolving credit facility maturing May 2021
Long-Term Debt and Liquidity Matters
Commercial paper			0
APS
Long-Term Debt and Liquidity Matters
Shot-term debt			83,300,000								0
Debt Provisions
Total shareholder equity			4,946,651,000								4,679,254,000
APS \| ACC
Debt Provisions
Total shareholder equity			4,900,000,000
Total capitalization			9,200,000,000
Dividend restrictions, shareholder equity required			$ 3,700,000,000
APS \| ACC \| Minimum
Debt Provisions
Required common equity ratio ordered by ACC (as a percent) (at least)			40.00%
APS \| Arizona pollution control corporation revenue refunding bonds, 2009 series A
Long-Term Debt and Liquidity Matters
Debt Instrument, repurchased face amount					$ 13,000,000
APS \| Revolving Credit Facility \| Revolving credit facility maturing in May 2019
Long-Term Debt and Liquidity Matters
Current borrowing capacity on credit facility							$ 500,000,000
APS \| Revolving Credit Facility \| Revolving Credit Facilities Maturing in 2020 and 2021
Long-Term Debt and Liquidity Matters
Current borrowing capacity on credit facility			$ 1,000,000,000
Maximum borrowing capacity on credit facility upon satisfaction of certain conditions and consent of lenders (up to)			1,400,000,000
Outstanding borrowings			$ 0
Number of line of credit facilities \| Facility			2
APS \| Revolving Credit Facility \| Revolving credit facility maturing May 2021
Long-Term Debt and Liquidity Matters
Current borrowing capacity on credit facility			$ 500,000,000			$ 500,000,000
Maximum borrowing capacity on credit facility upon satisfaction of certain conditions and consent of lenders (up to)			700,000,000
APS \| Revolving Credit Facility \| Revolving credit facility maturing September 2020
Long-Term Debt and Liquidity Matters
Current borrowing capacity on credit facility			500,000,000
Maximum borrowing capacity on credit facility upon satisfaction of certain conditions and consent of lenders (up to)			700,000,000
APS \| Commercial paper
Long-Term Debt and Liquidity Matters
Maximum commercial paper support available under credit facility			500,000,000							$ 500,000,000	$ 250,000,000
APS \| Commercial paper \| Revolving Credit Facilities Maturing in 2020 and 2021
Long-Term Debt and Liquidity Matters
Commercial paper			$ 83,000,000
APS \| Secured debt \| Term loan facility maturing April 22, 2019
Long-Term Debt and Liquidity Matters
Debt issued									$ 100,000,000
Senior Notes \| APS \| Unsecured senior notes 3.75 percent mature on 15 May, 2046
Long-Term Debt and Liquidity Matters
Debt issued								$ 350,000,000
Debt instrument, stated interest rate								3.75%
Senior Notes \| APS \| Unsecured senior notes 6.25 percent maturing on 01 August, 2016
Long-Term Debt and Liquidity Matters
Debt instrument, stated interest rate		6.25%
Repayments of debt		$ 250,000,000
Senior Notes \| APS \| Unsecured senior notes 2.55 percent maturing on 15 September, 2026
Long-Term Debt and Liquidity Matters
Debt issued				$ 250,000,000
Debt instrument, stated interest rate				2.55%
Current Maturities of Long-term Debt \| APS \| Arizona pollution control corporation revenue refunding bonds, 2009 series D and E
Long-Term Debt and Liquidity Matters
Debt Instrument, repurchased face amount					$ 64,000,000
Current Maturities of Long-term Debt \| APS \| Arizona pollution control corporation revenue refunding bond, 2009 series B
Long-Term Debt and Liquidity Matters
Debt Instrument, repurchased face amount				$ 27,000,000
LIBOR \| Pinnacle West \| Revolving Credit Facility \| Revolving credit facility maturing in August 2017
Long-Term Debt and Liquidity Matters
Debt instrument, basis spread on variable rate	0.80%