Number Of Branches

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- Definition

-- None. No documentation exists for this element. --

+ References

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- Definition

Useful life of assets common to business units owned by public utility, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Composite depreciation rate for public utility plants in service.

+ References

No definition available.

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- Definition

Useful life of utility generation assets owned by public utility, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Useful life of utility transmission and distribution equipment owned by public utility, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- Definition

Amount of cash and cash equivalents restricted as to withdrawal or usage, classified as current. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(1))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 8
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482913/230-10-50-8

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-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 4
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482740/230-10-45-4

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Summary of significant accounting policies - General, Cash, and PPE (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2023 USD ($) branch	Dec. 31, 2022 USD ($)	Dec. 31, 2021
Significant Accounting Policies [Line Items]
Number of branches	35
Restricted cash \| $	$ 15,000	$ 5,100
Hawaiian Electric Company, Inc. and Subsidiaries
Significant Accounting Policies [Line Items]
Composite annual depreciation rate (as percent)	3.20%	3.20%	3.20%
Minimum
Significant Accounting Policies [Line Items]
Estimated useful life under production plant (in years)	16 years
Estimated useful life under transmission and distribution plant (in years)	10 years
Estimated useful life under general plant (in years)	5 years
Maximum
Significant Accounting Policies [Line Items]
Estimated useful life under production plant (in years)	51 years
Estimated useful life under transmission and distribution plant (in years)	79 years
Estimated useful life under general plant (in years)	50 years
Hawaiian Electric Company, Inc. and Subsidiaries
Significant Accounting Policies [Line Items]
Restricted cash \| $	$ 2,000	$ 0
Oahu
Significant Accounting Policies [Line Items]
Number of branches	25
Maui
Significant Accounting Policies [Line Items]
Number of branches	4
Hawaii
Significant Accounting Policies [Line Items]
Number of branches	3
Kauai
Significant Accounting Policies [Line Items]
Number of branches	2
Molokai
Significant Accounting Policies [Line Items]
Number of branches	1