Monthly Capacity Charge as Percent of Company's Charge

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- Definition

Percentage of Purchase Power Obligations

+ References

No definition available.

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- Definition

Power Delivery Agreement, in MW

+ References

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- Definition

Power Purchase Agreement, in MW

+ References

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- Definition

The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3213-108585

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- Definition

Minimum amount of purchase arrangement in which the entity has agreed to expend funds to procure goods or services from a supplier.

+ References

No definition available.

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- Definition

Amount of purchase arrangement to be paid after fifth fiscal year following current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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Amount of purchase arrangement to be paid in fifth fiscal year following current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of purchase arrangement to be paid in fourth fiscal year following current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of purchase arrangement to be paid in next fiscal year following current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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Amount of purchase arrangement to be paid in second fiscal year following current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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Amount of purchase arrangement to be paid in third fiscal year following current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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- References

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COMMITMENTS AND CONTINGENCIES (Commitments) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2021 USD ($) MW	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Jul. 31, 2021 MW
Purchase Obligation, Fiscal Year Maturity [Abstract]
2022	$ 248,000
2023	228,000
2024	137,000
2025	125,000
2026	114,000
Thereafter	1,018,000
Total	1,870,000
Capital expenditures	$ 499,405	$ 839,958	$ 607,593
UNS Electric
Purchase Obligation, Fiscal Year Maturity [Abstract]
Power delivery agreement, in MW \| MW				150
Monthly capacity charge as percent of company's charge				50.00%
Capacity, Power, and Ancillary Services \| Maximum
Purchase Obligation, Fiscal Year Maturity [Abstract]
Power purchase agreement, in MW \| MW	300
Fuel, Including Transportation
Purchase Obligation, Fiscal Year Maturity [Abstract]
2022	$ 83,000
2023	74,000
2024	36,000
2025	28,000
2026	25,000
Thereafter	144,000
Total	390,000
Purchased Power
Purchase Obligation, Fiscal Year Maturity [Abstract]
2022	47,000
2023	47,000
2024	0
2025	0
2026	0
Thereafter	0
Total	94,000
Transmission
Purchase Obligation, Fiscal Year Maturity [Abstract]
2022	31,000
2023	20,000
2024	15,000
2025	13,000
2026	5,000
Thereafter	4,000
Total	88,000
Renewable Power Purchase Agreements
Purchase Obligation, Fiscal Year Maturity [Abstract]
2022	80,000
2023	80,000
2024	79,000
2025	79,000
2026	79,000
Thereafter	847,000
Total	$ 1,244,000
Percentage of purchase power obligations (in percentage)	100.00%
RES Performance-Based Incentives
Purchase Obligation, Fiscal Year Maturity [Abstract]
2022	$ 7,000
2023	7,000
2024	7,000
2025	5,000
2026	5,000
Thereafter	23,000
Total	$ 54,000