Bank segment (HEI only) - Capital And Ratio (Details) - American Savings Bank (ASB) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Tier 1 leverage, actual capital	$ 606,291	$ 571,810
Tier 1 leverage, actual ratio	8.70%	8.58%
Tier 1 leverage, required capital	$ 278,811	$ 266,430
Tier 1 leverage, required ratio	4.00%	4.00%
Tier 1 leverage, required to be well capitalized capital	$ 348,514	$ 333,038
Tier 1 leverage, required to be well capitalized ratio	5.00%	5.00%
Common equity tier 1, actual capital	$ 606,291	$ 571,810
Common equity tier 1, actual ratio	12.80%	12.95%
Common equity tier 1, required capital	$ 213,190	$ 198,628
Common equity tier 1, required ratio	4.50%	4.50%
Common equity tier 1, required to be well capitalized, Capital	$ 307,941	$ 286,907
Common equity tier 1, required to be well capitalized, Ratio	6.50%	6.50%
Tier 1 capital, actual capital	$ 606,291	$ 571,810
Tier 1 capital, actual ratio	12.80%	12.95%
Tier 1 capital, required capital	$ 284,253	$ 264,838
Tier 1 capital, required ratio	6.00%	6.00%
Tier 1 capital, Required to be well capitalized, Capital	$ 379,004	$ 353,117
Tier 1 capital, Required to be well capitalized, Ratio	8.00%	8.00%
Total capital, Actual capital	$ 660,151	$ 626,987
Total capital, Actual ratio	13.93%	14.20%
Total capital, Required capital	$ 379,004	$ 353,117
Total capital, Required ratio	8.00%	8.00%
Total capital, Required to be well capitalized, Capital	$ 473,755	$ 441,396
Total capital, Required to be well capitalized, Ratio	10.00%	10.00%

Common Equity Tier One Required To Be Well Caplitalized To Risk Weighted Assets

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Common Equity Tier One Required for Capital Adequacy to Average Assets

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Common Equity Tier One To Average Assets

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The amount of total capital as defined in the regulations.

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The minimum amount of Total Capital required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The minimum Total risk based capital ratio (total capital divided by risk weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The amount of Total Capital required to be categorized as well as capitalized under the regulatory framework for prompt corrective action.

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The Total risk based capital ratio (total capital divided by risk weighted assets) required to be categorized as "well capitalized", in the regulatory framework for prompt corrective action.

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Total Capital divided by risk weighted assets as defined in the regulations.

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Amount of Common Equity Tier One Risk-based Capital, as defined by regulatory framework.

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Amount of Common Equity Tier 1 Risk-based Capital required to be categorized as adequately capitalized under regulatory framework for prompt corrective action.

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Amount of Common Equity Tier 1 Risk-based Capital required to be categorized as well-capitalized under regulatory framework for prompt corrective action.

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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.

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Tier 1 Leverage Capital as defined in the regulations. Also called Core Capital.

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The minimum amount of Tier 1 Leverage Capital required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The minimum amount of Tier 1 Leverage Capital for capital adequacy purposes divided by average assets as defined in the regulations.

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The amount of Tier 1 Leverage Capital required to be categorized as well capitalized under the regulatory framework for prompt corrective action.

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Tier 1 Leverage Capital divided by average assets as defined in the regulations.

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Tier 1 Risk Based Capital as defined in the regulations.

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The minimum amount of Tier 1 Risk Based Capital required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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Tier 1 capital divided by risk weighted assets as defined by regulations.

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