Cash flows (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Supplemental disclosures of cash flow information
Interest paid to non-affiliates	$ 83,000	$ 84,000	$ 85,000
Income taxes paid	75,000	47,000	18,000
Income taxes refunded	55,000	24,000	4,000
Supplemental disclosures of noncash activities
Unpaid invoices and other	5,000	43,000	(12,000)
Common stock dividends reinvested in HEI common stock (financing)	0	0	24,000
Loans transferred from held for investment to held for sale (investing to operating)	0	0	25,000
Real estate acquired in settlement of loans (investing)	1,000	3,000	4,000
Real estate transferred from property, plant and equipment to other assets held-for-sale (investing)	5,000	0	0
Obligations to fund low income housing investments, net (operating)	4,000	14,000	1,000
Electric utility property, plant and equipment
AFUDC-equity	6,928	6,771	5,561
Hawaiian Electric Company, Inc. and Subsidiaries
Supplemental disclosures of cash flow information
Interest paid to non-affiliates	61,000	61,000	59,000
Income taxes paid	13,000	6,000	6,000
Income taxes refunded	12,000	8,000	32,000
Supplemental disclosures of noncash activities
Unpaid invoices and other	5,000	40,000	(12,000)
Electric utility property, plant and equipment
AFUDC-equity	6,928	6,771	5,561
Estimated fair value of noncash contributions in aid of construction	3,000	3,000	5,000
Refinancing of long-term debt (financing)	$ 47	$ 0	$ 0