Energy Purchase Contracts (Future Contractual Commitments For Power Resources And Natural Gas Resources) (Details) $ in Thousands	Dec. 31, 2021 USD ($)
Energy Purchase Contracts [Line Items]
2022	$ 285,280
2023	254,060
2024	243,274
2025	230,300
2026	216,324
Thereafter	2,271,019
Total	3,500,257
Power Resources [Member]
Energy Purchase Contracts [Line Items]
2022	198,052
2023	187,552
2024	200,693
2025	193,877
2026	184,230
Thereafter	1,888,038
Total	2,852,442
Natural Gas Resources [Member]
Energy Purchase Contracts [Line Items]
2022	87,228
2023	66,508
2024	42,581
2025	36,423
2026	32,094
Thereafter	382,981
Total	647,815
Generation Transmission And Distribution Facilities [Member]
Energy Purchase Contracts [Line Items]
2022	28,912
2023	29,680
2024	30,471
2025	31,287
2026	32,127
Thereafter	212,852
Total	$ 365,329

Energy Purchase Contracts [Line Items]

No definition available.

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- Definition

Amount of fixed and determinable portion of unrecorded unconditional purchase obligation to be paid in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 440
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123406679&loc=d3e25336-109308

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Amount of fixed and determinable portion of unrecorded unconditional purchase obligation to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

+ Details

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- Definition

Amount of fixed and determinable portion of unrecorded unconditional purchase obligation to be paid in fourth fiscal year following current fiscal year. 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 fixed and determinable portion of unrecorded unconditional purchase obligation to be paid in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of fixed and determinable portion of unrecorded unconditional purchase obligation to be paid in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of the unrecorded obligation to transfer funds in the future for fixed or minimum amounts or quantities of goods or services at fixed or minimum prices (for example, as in take-or-pay contracts or throughput contracts).

+ References

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- Definition

Amount of fixed and determinable portion of unrecorded unconditional purchase obligation to be paid after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 440
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123406679&loc=d3e25336-109308

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