Leases - Maturity of Operating Lease Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Lessee, Lease, Description [Line Items]
2022	$ 57,000
2023	17,000
2024	15,000
2025	11,000
2026	10,000
Thereafter	40,000
Total lease payments	150,000
Less: Imputed interest	(13,000)
Total present value of lease payments	136,760	$ 160,432
Operating lease, not in service, annual capacity payment	3,800
Other leases
Lessee, Lease, Description [Line Items]
2022	11,000
2023	13,000
2024	11,000
2025	7,000
2026	7,000
Thereafter	36,000
Total lease payments	85,000
Less: Imputed interest	(11,000)
Total present value of lease payments	74,000
PPAs classified as leases
Lessee, Lease, Description [Line Items]
2022	46,000
2023	4,000
2024	4,000
2025	4,000
2026	3,000
Thereafter	4,000
Total lease payments	65,000
Less: Imputed interest	(2,000)
Total present value of lease payments	63,000
Hawaiian Electric Company, Inc. and Subsidiaries
Lessee, Lease, Description [Line Items]
2022	52,000
2023	12,000
2024	11,000
2025	9,000
2026	8,000
Thereafter	34,000
Total lease payments	126,000
Less: Imputed interest	(11,000)
Total present value of lease payments	115,000
Hawaiian Electric Company, Inc. and Subsidiaries \| Other leases
Lessee, Lease, Description [Line Items]
2022	6,000
2023	8,000
2024	7,000
2025	5,000
2026	5,000
Thereafter	30,000
Total lease payments	61,000
Less: Imputed interest	(9,000)
Total present value of lease payments	52,000
Hawaiian Electric Company, Inc. and Subsidiaries \| PPAs classified as leases
Lessee, Lease, Description [Line Items]
2022	46,000
2023	4,000
2024	4,000
2025	4,000
2026	3,000
Thereafter	4,000
Total lease payments	65,000
Less: Imputed interest	(2,000)
Total present value of lease payments	$ 63,000

Lessee, Operating Lease, Not In Service, Annual Capacity Payment

No definition available.

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Balance Type:	credit
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=123408670&loc=SL77918701-209980

+ Details

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Balance Type:	credit
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- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease due after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

+ Details

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- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

+ Details

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- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

+ Details

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- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

+ Details

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- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

+ Details

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- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

+ Details

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Balance Type:	credit
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- Definition

Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for operating lease.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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- Definition

Present value of lessee's discounted obligation for lease payments from operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123391704&loc=SL77918627-209977

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