Consolidated Statements of Capitalization - HECO (Parenthetical) - $ / shares	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015
Common stock, authorized shares	200,000,000	200,000,000
Common stock, outstanding shares	108,583,413	107,460,406
6.50 %, series 2004, Junior subordinated deferrable interest debentures, due 2034
Debt instrument, stated interest rate (as a percent)	6.50%	6.50%
Hawaiian Electric Company, Inc. and Subsidiaries
Common stock, par value (in dollars per share)	$ 6.667	$ 6.667
Common stock, authorized shares	50,000,000	50,000,000
Common stock, outstanding shares	160,196,785	15,805,327
Shares outstanding December 31, 2013	1,234,657	1,234,657
Hawaiian Electric Company, Inc. and Subsidiaries \| Series C, 4.25% Preferred Stock
Preferred stock, par value (in dollars per share)	$ 20	$ 20
Preferred stock, dividend rate	4.25%	4.25%
Shares outstanding December 31, 2013	150,000	150,000
Hawaiian Electric Company, Inc. and Subsidiaries \| Series D, 5.00% Preferred Stock
Preferred stock, par value (in dollars per share)	$ 20	$ 20
Preferred stock, dividend rate	5.00%	5.00%
Shares outstanding December 31, 2013	50,000	50,000
Hawaiian Electric Company, Inc. and Subsidiaries \| Series E, 5.00% Preferred Stock
Preferred stock, par value (in dollars per share)	$ 20	$ 20
Preferred stock, dividend rate	5.00%	5.00%
Shares outstanding December 31, 2013	150,000	150,000
Hawaiian Electric Company, Inc. and Subsidiaries \| Series H, 5.25% Preferred Stock
Preferred stock, par value (in dollars per share)	$ 20	$ 20
Preferred stock, dividend rate	5.25%	5.25%
Shares outstanding December 31, 2013	250,000	250,000
Hawaiian Electric Company, Inc. and Subsidiaries \| Series I, 5.00% Preferred Stock
Preferred stock, par value (in dollars per share)	$ 20	$ 20
Preferred stock, dividend rate	5.00%	5.00%
Shares outstanding December 31, 2013	89,657	89,657
Hawaiian Electric Company, Inc. and Subsidiaries \| Series J, 4.75% Preferred Stock
Preferred stock, par value (in dollars per share)	$ 20	$ 20
Preferred stock, dividend rate	4.75%	4.75%
Shares outstanding December 31, 2013	250,000	250,000
Hawaiian Electric Company, Inc. and Subsidiaries \| Series K, 4.65% Preferred Stock
Preferred stock, par value (in dollars per share)	$ 20	$ 20
Preferred stock, dividend rate	4.65%	4.65%
Shares outstanding December 31, 2013	175,000	175,000
Hawaiian Electric Company, Inc. and Subsidiaries \| Preferred Stock $20 Par Value
Preferred stock, par value (in dollars per share)	$ 20	$ 20
Preferred stock, Authorized shares	5,000,000	5,000,000
Hawaiian Electric Company, Inc. and Subsidiaries \| Preferred Stock $100 Par Value
Preferred stock, par value (in dollars per share)	$ 100	$ 100
Preferred stock, Authorized shares	7,000,000	7,000,000
Hawaiian Electric Company, Inc (HECO) \| 3.25% Refunding Series 2015 SPRBs due 2025
Debt instrument, stated interest rate (as a percent)	3.25%	3.25%
Hawaiian Electric Company, Inc (HECO) \| 6.50%, series 2009, due 2039
Debt instrument, stated interest rate (as a percent)	6.50%	6.50%
Hawaiian Electric Company, Inc (HECO) \| 4.60%, refunding series 2007B, due 2026
Debt instrument, stated interest rate (as a percent)	4.60%	4.60%
Hawaiian Electric Company, Inc (HECO) \| 4.65%, series 2007A, due 2037
Debt instrument, stated interest rate (as a percent)	4.65%	4.65%
Hawaiian Electric Company, Inc (HECO) \| Hawaiian Electric, 5.23%, Series 2015A, due 2045
Debt instrument, stated interest rate (as a percent)	5.23%	5.23%
Hawaiian Electric Company, Inc (HECO) \| Hawaiian Electric, 4.45%, Series 2013A, due 2022
Debt instrument, stated interest rate (as a percent)	4.45%	4.45%
Hawaiian Electric Company, Inc (HECO) \| Hawaiian Electric, 4.84%, Series 2013B, due 2027
Debt instrument, stated interest rate (as a percent)	4.84%	4.84%
Hawaiian Electric Company, Inc (HECO) \| Hawaiian Electric, 5.65%, Series 2013C, due 2043
Debt instrument, stated interest rate (as a percent)	5.65%	5.65%
Hawaiian Electric Company, Inc (HECO) \| Senior notes 3.79%, Series 2012A, due 2018
Debt instrument, stated interest rate (as a percent)	3.79%	3.79%
Hawaiian Electric Company, Inc (HECO) \| Senior notes 4.03%, Series 2012B, due 2020
Debt instrument, stated interest rate (as a percent)	4.03%	4.03%
Hawaiian Electric Company, Inc (HECO) \| Senior notes 4.55%, due 2023
Debt instrument, stated interest rate (as a percent)	4.55%	4.55%
Hawaiian Electric Company, Inc (HECO) \| Hawaiian Electric, 4.72%, Series 2012D, due 2029
Debt instrument, stated interest rate (as a percent)	4.72%	4.72%
Hawaiian Electric Company, Inc (HECO) \| Hawaiian Electric, 5.39%, Series 2012E, due 2042
Debt instrument, stated interest rate (as a percent)	5.39%	5.39%
Hawaiian Electric Company, Inc (HECO) \| Hawaiian Electric, 4.53%, Series 2012F, due 2032
Debt instrument, stated interest rate (as a percent)	4.53%	4.53%
Hawaiian Electric Company, Inc (HECO) \| Hawaiian Electric, 4.54%, Series 2016A, due 2046
Debt instrument, stated interest rate (as a percent)	4.54%	4.54%
Hawaii Electric Light Company, Inc. (HELCO) \| Series G, 7.625% Preferred Stock
Preferred stock, par value (in dollars per share)	$ 100	$ 100
Preferred stock, dividend rate	7.625%	7.625%
Shares outstanding December 31, 2013	70,000	70,000
Hawaii Electric Light Company, Inc. (HELCO) \| 3.25% Refunding Series 2015 SPRBs due 2025
Debt instrument, stated interest rate (as a percent)	3.25%	3.25%
Hawaii Electric Light Company, Inc. (HELCO) \| 6.50%, series 2009, due 2039
Debt instrument, stated interest rate (as a percent)	6.50%	6.50%
Hawaii Electric Light Company, Inc. (HELCO) \| 4.60%, refunding series 2007B, due 2026
Debt instrument, stated interest rate (as a percent)	4.60%	4.60%
Hawaii Electric Light Company, Inc. (HELCO) \| 4.65%, series 2007A, due 2037
Debt instrument, stated interest rate (as a percent)	4.65%	4.65%
Hawaii Electric Light Company, Inc. (HELCO) \| Hawaii Electric Light, 5.23%, Series 2015A, due 2045
Debt instrument, stated interest rate (as a percent)	5.23%	5.23%
Hawaii Electric Light Company, Inc. (HELCO) \| Hawaii Electric Light, 3.83%, Series 2013A, due 2020
Debt instrument, stated interest rate (as a percent)	3.83%	3.83%
Hawaii Electric Light Company, Inc. (HELCO) \| Hawaii Electric Light, 4.45%, Series 2013B, due 2022
Debt instrument, stated interest rate (as a percent)	4.45%	4.45%
Hawaii Electric Light Company, Inc. (HELCO) \| Hawaii Electric Light, 4.84%, Series 2013C, due 2027
Debt instrument, stated interest rate (as a percent)	4.84%	4.84%
Hawaii Electric Light Company, Inc. (HELCO) \| Senior notes 3.79%, Series 2012A, due 2018
Debt instrument, stated interest rate (as a percent)	3.79%	3.79%
Hawaii Electric Light Company, Inc. (HELCO) \| Senior notes 4.55%, due 2023
Debt instrument, stated interest rate (as a percent)	4.55%	4.55%
Maui Electric Company, Limited (MECO) \| Series H, 7.625% Preferred Stock
Preferred stock, par value (in dollars per share)	$ 100	$ 100
Preferred stock, dividend rate	7.625%	7.625%
Shares outstanding December 31, 2013	50,000	50,000
Maui Electric Company, Limited (MECO) \| 3.25% Refunding Series 2015 SPRBs due 2025
Debt instrument, stated interest rate (as a percent)	3.25%	3.25%
Maui Electric Company, Limited (MECO) \| 4.60%, refunding series 2007B, due 2026
Debt instrument, stated interest rate (as a percent)	4.60%	4.60%
Maui Electric Company, Limited (MECO) \| 4.65%, series 2007A, due 2037
Debt instrument, stated interest rate (as a percent)	4.65%	4.65%
Maui Electric Company, Limited (MECO) \| Maui Electric, 5.23%, Series 2015A, due 2045
Debt instrument, stated interest rate (as a percent)	5.23%	5.23%
Maui Electric Company, Limited (MECO) \| Maui Electric, 4.84%, Series 2013A, due 2027
Debt instrument, stated interest rate (as a percent)	4.84%	4.84%
Maui Electric Company, Limited (MECO) \| Maui Electric, 5.65%, Series 2013B, due 2043
Debt instrument, stated interest rate (as a percent)	5.65%	5.65%
Maui Electric Company, Limited (MECO) \| Senior notes 3.79%, Series 2012A, due 2018
Debt instrument, stated interest rate (as a percent)	3.79%	3.79%
Maui Electric Company, Limited (MECO) \| Senior notes 4.03%, Series 2012B, due 2020
Debt instrument, stated interest rate (as a percent)	4.03%	4.03%
Maui Electric Company, Limited (MECO) \| Senior notes 4.55%, due 2023
Debt instrument, stated interest rate (as a percent)	4.55%	4.55%

Face amount or stated value per share of common stock.

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

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Contractual interest rate for funds borrowed, under the debt agreement.

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The percentage rate used to calculate dividend payments on preferred stock.

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No definition available.

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Per share amount of par value or stated value of stock classified as temporary equity. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (27)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 480
-SubTopic 10
-Section S99
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=65877616&loc=d3e177068-122764

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The maximum number of securities classified as temporary equity that are permitted to be issued by an entity's charter and bylaws. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. If convertible, the issuer does not control the actions or events necessary to issue the maximum number of shares that could be required to be delivered under the conversion option if the holder exercises the option to convert the stock to another class of equity. If the security is a warrant or a rights issue, the warrant or rights issue is considered to be temporary equity if the issuer cannot demonstrate that it would be able to deliver upon the exercise of the option by the holder in all cases. Includes stock with put option held by ESOP and stock redeemable by holder only in the event of a change in control of the issuer.

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The number of securities classified as temporary equity that have been issued and are held by the entity's shareholders. Securities outstanding equals securities issued minus securities held in treasury. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. If convertible, the issuer does not control the actions or events necessary to issue the maximum number of shares that could be required to be delivered under the conversion option if the holder exercises the option to convert the stock to another class of equity. If the security is a warrant or a rights issue, the warrant or rights issue is considered to be temporary equity if the issuer cannot demonstrate that it would be able to deliver upon the exercise of the option by the holder in all cases. Includes stock with put option held by ESOP and stock redeemable by holder only in the event of a change in control of the issuer.

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