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Operations and Significant Accounting Policies - Concentration of Credit Risk (Details) - Customer Concentration Risk [Member] - Large Power Customers [Member] $ in Millions | 12 Months Ended
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Dec. 31, 2022 USD ($) Customers | Dec. 31, 2021 USD ($) | Dec. 31, 2020
Concentration Risk [Line Items] |  |  |
Number of Large Power Customers | 7 |  |
Receivables from Large Power Customers | $ | $ 11.3 | $ 7.8 |
Number of entities | 2 |  |
Largest Customer [Member] | Consolidated Operating Revenue [Member] |  |  |
Concentration Risk [Line Items] |  |  |
Percent of Operating Revenue | 26.00% | 28.00% | 25.00%
Largest Customer [Member] | Consolidated Operating Revenue [Member] | Regulated Operations [Member] |  |  |
Concentration Risk [Line Items] |  |  |
Percent of Operating Revenue | 32.00% | 32.00% | 29.00%

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- Definition Amount, before allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 45 -Paragraph 2 -URI https://asc.fasb.org/extlink&oid=124259787&loc=d3e4428-111522 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(3)(a)(1)) -URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
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