Energy Purchase Contracts (Future Contractual Commitments For Power Resources And Natural Gas Resources) (Details) $ in Thousands	Dec. 31, 2023 USD ($)
Energy Purchase Contracts [Line Items]
2023	$ 459,007
2024	374,530
2025	312,284
2026	277,459
2027	275,924
Thereafter	2,526,324
Total	4,225,528
Power Resources [Member]
Energy Purchase Contracts [Line Items]
2023	336,766
2024	293,389
2025	266,251
2026	235,751
2027	234,756
Thereafter	2,245,762
Total	3,612,675
Natural Gas Resources [Member]
Energy Purchase Contracts [Line Items]
2023	122,241
2024	81,141
2025	46,033
2026	41,708
2027	41,168
Thereafter	280,562
Total	612,853
Generation Transmission And Distribution Facilities [Member]
Energy Purchase Contracts [Line Items]
2023	39,156
2024	40,226
2025	18,630
2026	19,085
2027	9,390
Thereafter	177,553
Total	$ 304,040

Energy Purchase Contracts [Line Items]

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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
-Topic 440
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482648/440-10-50-4

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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

+ Details

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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

+ Details

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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

+ Details

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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
-Topic 440
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482648/440-10-50-4

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