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Electric utility segment - Power purchase agreements (Details) - Hawaiian Electric (parent only) - USD ($) $ in Millions | 3 Months Ended
--- | ---
Mar. 31, 2020 | Mar. 31, 2019
Regulatory Projects and Legal Obligations [Line Items] |  |
Purchased power | $ 140 | $ 134
Kalaeloa |  |
Regulatory Projects and Legal Obligations [Line Items] |  |
Purchased power | 38 | 40
AES Hawaii |  |
Regulatory Projects and Legal Obligations [Line Items] |  |
Purchased power | 31 | 32
HPOWER |  |
Regulatory Projects and Legal Obligations [Line Items] |  |
Purchased power | 17 | 18
Hamakua Energy |  |
Regulatory Projects and Legal Obligations [Line Items] |  |
Purchased power | 13 | 16
Wind IPPs |  |
Regulatory Projects and Legal Obligations [Line Items] |  |
Purchased power | 28 | 20
Solar IPPs |  |
Regulatory Projects and Legal Obligations [Line Items] |  |
Purchased power | 11 | 7
Other IPPs |  |
Regulatory Projects and Legal Obligations [Line Items] |  |
Purchased power | $ 2 | $ 1

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- Definition Amount of operating expense for purchased power of regulated operation. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.2(b)) -URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227 + Details
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