SCHEDULE I - CONDENSED FINANCIAL INFORMATION OF REGISTRANT- BALANCE SHEETS (Details) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Assets
Cash and cash equivalents	$ 278,452,000	$ 300,478,000	$ 175,542,000	$ 220,036,000
Accounts receivable	237,950,000	242,766,000
Property, plant and equipment, net	4,603,465,000	4,377,658,000
Other assets	447,621,000	480,457,000
Total assets	12,425,506,000	11,782,018,000	11,177,143,000
Liabilities
Accounts payable	143,279,000	138,523,000
Long-term debt	1,619,019,000	1,578,368,000
Other	473,512,000	471,828,000
Total liabilities	10,324,460,000	9,820,085,000
Shareholders' equity
Preferred stock, no par value, authorized 10,000,000 shares; issued: none	0	0
Common stock equity	1,660,910,000	1,629,136,000
Retained earnings	438,972,000	324,766,000
Accumulated other comprehensive loss	(33,129,000)	(26,262,000)
Total shareholders’ equity	2,066,753,000	1,927,640,000	1,790,573,000	1,726,406,000
Total capitalization and liabilities	12,425,506,000	11,782,018,000
Less unamortized debt issuance costs	(241,000)	$ (334,000)
Aggregate principal payments
2017	125,000,000
2018	125,000,000
2019	0
2020	96,000,000
2021	$ 50,000,000
Preferred stock, authorized shares	10,000,000	10,000,000
Preferred stock, shares issued	0	0
Common stock, authorized shares	200,000,000	200,000,000
Common stock, issued shares	108,583,413	107,460,406
Common stock, outstanding shares	108,583,413	107,460,406
Self-insured United States longshore & Harbor bond
Aggregate principal payments
Guarantee obligation maximum exposure	$ 200,000
Self-insured automobile bond
Aggregate principal payments
Guarantee obligation maximum exposure	$ 600,000
HEI Term loan LIBOR .75%, due 2017 | LIBOR
Shareholders' equity
Line of credit facility basis point spread (as a percent)	0.75%
HEI term loan LIBOR .75%, due 2018 | LIBOR
Shareholders' equity
Line of credit facility basis point spread (as a percent)	0.75%
Hawaiian Electric Industries, Inc.
Assets
Cash and cash equivalents	$ 14,924,000	$ 55,116,000	$ 276,000	$ 571,000
Accounts receivable	3,788,000	5,459,000
Property, plant and equipment, net	4,143,000	4,514,000
Deferred income tax assets	17,280,000	16,715,000
Other assets	9,858,000	11,650,000
Investments in subsidiaries, at equity	2,383,405,000	2,293,679,000
Total assets	2,433,398,000	2,387,133,000
Liabilities
Accounts payable	379,000	1,254,000
Interest payable	1,735,000	2,450,000
Notes payable to subsidiaries	5,373,000	5,946,000
Commercial paper	0	103,063,000
Long-term debt	299,759,000	299,666,000
Retirement benefits liability	33,939,000	31,704,000
Other	25,460,000	15,410,000
Total liabilities	366,645,000	459,493,000
Shareholders' equity
Preferred stock, no par value, authorized 10,000,000 shares; issued: none	0	0
Common stock equity	1,660,910,000	1,629,136,000
Retained earnings	438,972,000	324,766,000
Accumulated other comprehensive loss	(33,129,000)	(26,262,000)
Total shareholders’ equity	2,066,753,000	1,927,640,000
Total capitalization and liabilities	2,433,398,000	2,387,133,000
Less unamortized debt issuance costs	(241,000)	$ (334,000)
Aggregate principal payments
2017	125,000,000
2018	75,000,000
2019	0
2020	0
2021	$ 50,000,000
Preferred stock, authorized shares	10,000,000	10,000,000
Preferred stock, shares issued	0	0
Common stock, authorized shares	200,000,000	200,000,000
Common stock, issued shares	108,583,413	107,460,406
Common stock, outstanding shares	108,583,413	107,460,406
Hawaiian Electric Industries, Inc. | HEI Term loan LIBOR .75%, due 2017
Liabilities
Long-term debt	$ 125,000,000	$ 125,000,000
Hawaiian Electric Industries, Inc. | HEI Term loan LIBOR .75%, due 2017 | LIBOR
Shareholders' equity
Line of credit facility basis point spread (as a percent)	75.00%
Hawaiian Electric Industries, Inc. | HEI term loan LIBOR .75%, due 2018
Liabilities
Long-term debt	$ 75,000,000	0
Hawaiian Electric Industries, Inc. | HEI term loan LIBOR .75%, due 2018 | LIBOR
Shareholders' equity
Line of credit facility basis point spread (as a percent)	75.00%
Hawaiian Electric Industries, Inc. | HEI senior note 4.41%, paid 2016
Liabilities
Long-term debt	$ 0	75,000,000
Shareholders' equity
Interest rate of medium-term notes (as a percent)	4.41%
Hawaiian Electric Industries, Inc. | HEI senior note 5.67%, due 2021
Liabilities
Long-term debt	$ 50,000,000	50,000,000
Shareholders' equity
Interest rate of medium-term notes (as a percent)	5.67%
Hawaiian Electric Industries, Inc. | HEI senior note 3.99%, due 2023
Liabilities
Long-term debt	$ 50,000,000	$ 50,000,000
Shareholders' equity
Interest rate of medium-term notes (as a percent)	3.99%