v3.20.2

Assets and Liabilities with Recurring Fair Value Measurements Quantitative Info on Level 3 (Details) - USD ($) | Jun. 30, 2020 | Dec. 31, 2019
--- | --- | ---
Fair Value Measurements Inputs and Valuation Techniques |  |  |
Derivative, fair value, net asset (liability) | [1] | $ 85,000,000 | $ 114,000,000
Power Contracts |  |  |
Fair Value Measurements Inputs and Valuation Techniques |  |  |
Derivative, fair value, net asset (liability) | [2] | 206,000,000 | 158,000,000
Power Contracts | Minimum [Member] |  |  |
Fair Value Measurements Inputs and Valuation Techniques |  |  |
Fair value inputs quantitative information |  | 3.18 | 4.85
Power Contracts | Maximum |  |  |
Fair Value Measurements Inputs and Valuation Techniques |  |  |
Fair value inputs quantitative information |  | 175.51 | 184.15
Power Contracts | Average |  |  |
Fair Value Measurements Inputs and Valuation Techniques |  |  |
Fair value inputs quantitative information | [3] | 28.97 |
Power Congestion Products |  |  |
Fair Value Measurements Inputs and Valuation Techniques |  |  |
Derivative, fair value, net asset (liability) |  | 6,000,000 | 17,000,000
Power Congestion Products | Minimum [Member] |  |  |
Fair Value Measurements Inputs and Valuation Techniques |  |  |
Fair value inputs quantitative information |  | (6.48) | (10.32)
Power Congestion Products | Maximum |  |  |
Fair Value Measurements Inputs and Valuation Techniques |  |  |
Fair value inputs quantitative information |  | 11.88 | 20.00
Power Congestion Products | Average |  |  |
Fair Value Measurements Inputs and Valuation Techniques |  |  |
Fair value inputs quantitative information | [3] | 1.20 |
Natural Gas Contracts |  |  |
Fair Value Measurements Inputs and Valuation Techniques |  |  |
Derivative, fair value, net asset (liability) |  | 9,000,000 | (20,000,000)
Natural Gas Contracts | Minimum [Member] |  |  |
Fair Value Measurements Inputs and Valuation Techniques |  |  |
Fair value inputs quantitative information |  | 1.33 | 1.73
Natural Gas Contracts | Maximum |  |  |
Fair Value Measurements Inputs and Valuation Techniques |  |  |
Fair value inputs quantitative information |  | 4.62 | $ 6.45
Natural Gas Contracts | Average |  |  |
Fair Value Measurements Inputs and Valuation Techniques |  |  |
Fair value inputs quantitative information | [3] | $ 2.82 |
[1] | At June 30, 2020 and December 31, 2019, we had $260 million and $191 million, respectively, of collateral under master netting arrangements that were not offset against our derivative instruments on the Consolidated Condensed Balance Sheets primarily related to initial margin requirements.
[2] | Power contracts include power and heat rate instruments classified as level 3 in the fair value hierarchy.
[3] | (2)Amount represents the arithmetic average of the significant unobservable input based on the range disclosed.

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- Definition Fair value of the assets less the liabilities of a derivative or group of derivatives. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=118260190&loc=d3e13433-108611 + Details
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