Bank segment (HEI only) - Capital And Ratio (Details) - American Savings Bank (ASB) $ in Thousands	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Tier 1 leverage, actual capital	$ 759,921	$ 750,851
Tier 1 leverage, actual ratio	0.0768	0.0778
Tier 1 leverage, required capital	$ 395,812	$ 386,265
Tier 1 leverage, required ratio	0.0400	0.0400
Tier 1 leverage, required to be well capitalized capital	$ 494,765	$ 482,831
Tier 1 leverage, required to be well capitalized ratio	0.0500	0.0500
Common equity tier 1, actual capital	$ 759,921	$ 750,851
Common equity tier 1, actual ratio	12.27%	12.15%
Common equity tier 1, required capital	$ 278,681	$ 278,076
Common equity tier 1, required ratio	4.50%	4.50%
Common equity tier 1, required to be well capitalized, capital	$ 402,539	$ 401,665
Common equity tier 1, required to be well capitalized, ratio	6.50%	6.50%
Tier 1 capital, actual capital	$ 759,921	$ 750,851
Tier 1 capital, actual ratio	0.1227	0.1215
Tier 1 capital, required capital	$ 371,575	$ 370,767
Tier 1 capital, required ratio	0.0600	0.0600
Tier 1 capital, required to be well capitalized, capital	$ 495,433	$ 494,356
Tier 1 capital, required to be well capitalized, ratio	0.0800	0.0800
Total capital, actual capital	$ 828,901	$ 811,729
Total capital, actual ratio	0.1338	0.1314
Total capital, required capital	$ 495,433	$ 494,356
Total capital, required ratio	0.0800	0.0800
Total capital, required to be well capitalized, capital	$ 619,291	$ 617,946
Total capital, required to be well capitalized, ratio	0.1000	0.1000

Common Equity Tier One Required For Capital Adequacy To Average Assets

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