Bank segment (HEI only) - Capital And Ratio (Details) - American Savings Bank (ASB) $ in Thousands	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Tier 1 leverage, actual capital	$ 714,789	$ 677,786
Tier 1 leverage, actual ratio	0.0786	0.0838
Tier 1 leverage, required capital	$ 363,630	$ 323,700
Tier 1 leverage, required ratio	0.0400	0.0400
Tier 1 leverage, required to be well capitalized capital	$ 454,538	$ 404,625
Tier 1 leverage, required to be well capitalized ratio	0.0500	0.0500
Common equity tier 1, actual capital	$ 714,789
Common equity tier 1, actual ratio	13.29%
Common equity tier 1, required capital	$ 242,072
Common equity tier 1, required ratio	4.50%
Common equity tier 1, required to be well capitalized, Capital	$ 349,659
Common equity tier 1, required to be well capitalized, Ratio	6.50%
Tier 1 capital, actual capital	$ 714,789
Tier 1 capital, actual ratio	0.1329
Tier 1 capital, required capital	$ 322,762
Tier 1 capital, required ratio	0.0600
Tier 1 capital, Required to be well capitalized, Capital	$ 430,350
Tier 1 capital, Required to be well capitalized, Ratio	0.0800
Total capital, Actual capital	$ 769,836
Total capital, Actual ratio	0.1431
Total capital, Required capital	$ 430,350
Total capital, Required ratio	0.0800
Total capital, Required to be well capitalized, Capital	$ 537,937
Total capital, Required to be well capitalized, Ratio	0.1000

Common Equity Tier One Required For Capital Adequacy To Average Assets

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Amount of minimum total risk-based capital required for capital adequacy as defined by regulatory framework.

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-Publisher FASB
-Name Accounting Standards Codification
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