Long-Term Debt and Liquidity Matters - Future Principal Payments (Details) $ in Thousands	Dec. 31, 2019 USD ($)
Pinnacle West
Principal payments due on long-term debt
2020	$ 800,000
2021	0
2022	0
2023	0
2024	365,150
Thereafter	4,510,975
Total	5,676,125
ARIZONA PUBLIC SERVICE COMPANY
Principal payments due on long-term debt
2020	350,000
2021	0
2022	0
2023	0
2024	365,150
Thereafter	4,510,975
Total	$ 5,226,125

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.

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