XML 66 R42.htm IDEA: XBRL DOCUMENT
v3.10.0.1

Commitments and Contingencies (Tables) | 12 Months Ended
--- | ---
Dec. 31, 2018
Commitments and Contingencies Disclosure [Abstract] |
Summary of estimated coal take-or-pay commitments | The following table summarizes our estimated coal take-or-pay commitments (dollars in thousands):
| Years Ended December 31,
| 2019 |  | 2020 |  | 2021 |  | 2022 |  | 2023 |  | Thereafter
Coal take-or-pay commitments (a) | $ | 179,879 |  |  | $ | 181,059 |  |  | $ | 184,944 |  |  | $ | 186,244 |  |  | $ | 187,518 |  |  | $ | 1,422,253 |
(a) Total take-or-pay commitments are approximately $2.3 billion. The total net present value of these commitments is approximately $1.7 billion.
Summary of actual take-or-pay commitments | The following table summarizes actual amounts purchased under the coal contracts which include take-or-pay provisions for each of the last three years (dollars in thousands):
| Year Ended December 31,
| 2018 |  | 2017 |  | 2016
Total purchases | $ | 206,093 |  |  | $ | 165,220 |  |  | $ | 160,066 |

X
- Definition Tabular disclosure of actual unconditional purchase obligations that are not recognized as a liability on the balance sheet, including the nature and significant terms of an unconditional purchase obligation; the amount of the fixed and determinable portion of the obligation as of the date of the latest balance sheet presented in the aggregate and, if determinable, for each of the five succeeding fiscal years; the nature of any variable component of the obligation; the amount purchased under the obligation (for example, the take-or-pay or throughput contract) for the reporting period; and may include the amount of imputed interest necessary to reduce the obligation to present value. + References No definition available. + Details
Name: | pnw_UnrecordedUnconditionalActualPurchaseObligationsDisclosureTableTextBlock
Namespace Prefix: | pnw_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of expected unconditional purchase obligations that are not recognized as a liability on the balance sheet, including the nature and significant terms of an unconditional purchase obligation; the amount of the fixed and determinable portion of the obligation as of the date of the latest balance sheet presented in the aggregate and, if determinable, for each of the five succeeding fiscal years; the nature of any variable components of the obligation; the amount purchased under the obligation (for example, the take-or-pay or throughput contract) for the reporting period; and may include the amount of imputed interest necessary to reduce the obligation to present value. + References No definition available. + Details
Name: | pnw_UnrecordedUnconditionalEstimatedPurchaseObligationsDisclosureTableTextBlock
Namespace Prefix: | pnw_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_CommitmentsAndContingenciesDisclosureAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration