Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2015	Oct. 31, 2015
Entity Information [Line Items]
Entity Registrant Name	HAWAIIAN ELECTRIC INDUSTRIES INC
Entity Central Index Key	0000354707
Document Type	10-Q
Document Period End Date	Sep. 30, 2015
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		107,458,641
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	Q3
Hawaiian Electric Company, Inc. and Subsidiaries
Entity Information [Line Items]
Entity Registrant Name	HAWAIIAN ELECTRIC COMPANY INC
Entity Central Index Key	0000046207
Document Type	10-Q
Document Period End Date	Sep. 30, 2015
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Filer Category	Non-accelerated Filer
Entity Common Stock, Shares Outstanding		15,805,327
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	Q3