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v3.10.0.1

ACQUISITION (Details) $ in Thousands | 1 Months Ended | 3 Months Ended
--- | --- | ---
Nov. 30, 2017 USD ($) | Oct. 31, 2017 USD ($) mi | Dec. 31, 2018 USD ($) | Dec. 31, 2017 USD ($)
Business Acquisition [Line Items] |  |  |  |
Payment made at closing |  |  | $ 0 | $ 10,000
Talen Generation, LLC |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Related party, service agreement, period |  |  | 10 years |
Talen Generation, LLC | Talen's Membership Interests In IEC |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Consideration to be transferred |  | $ 166,000 |  |
Contingent consideration arrangements, additional consideration |  | $ 23,000 |  |
Payment made at closing | $ 10,000 |  |  |
Pipeline length owned | mi |  | 84 |  |

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