Cash flows (Details) (USD $) In Millions, unless otherwise specified	6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013
Supplemental disclosures of cash flow information
Interest paid	$ 44	$ 43
Income taxes paid	22	5
Income taxes refunded	24	4
Supplemental disclosures of noncash activities
Common stock dividends reinvested in HEI common stock	0	12
Increases in common stock related to director and officer compensatory plans	2	1
Real estate acquired in settlement of loans	2	3
Loans transferred from held-for-investment to held-for-sale	0	25
Obligations to fund low income housing investments	8	0
Additions to electric utility property, plant and equipment - unpaid invoices and other	28	5
Hawaiian Electric Company, Inc. and Subsidiaries
Supplemental disclosures of cash flow information
Interest paid	31	30
Income taxes paid	6	6
Income taxes refunded	8	32
Supplemental disclosures of noncash activities
Additions to electric utility property, plant and equipment - unpaid invoices and other	$ 28	$ 5