Long-Term Debt and Liquidity Matters - Future Principal Payments (Details) $ in Thousands	Dec. 31, 2016 USD ($)
Pinnacle West
Principal payments due on long-term debt
2017	$ 125,000
2018	82,000
2019	600,000
2020	250,000
2021	0
Thereafter	3,126,125
Total	4,183,125
ARIZONA PUBLIC SERVICE COMPANY
Principal payments due on long-term debt
2017	0
2018	82,000
2019	600,000
2020	250,000
2021	0
Thereafter	3,126,125
Total	$ 4,058,125

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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