Cash flows (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013
Supplemental disclosures of cash flow information
Interest paid	$ 64	$ 62
Income taxes paid	31	6
Income taxes refunded	24	4
Supplemental disclosures of noncash activities
Common stock dividends reinvested in HEI common stock	0	18
Increases in common stock related to director and officer compensatory plans	4	3
Real estate acquired in settlement of loans	2	4
Loans transferred from held-for-investment to held-for-sale	0	25
Obligations to fund low income housing investments	6	0
Additions to electric utility property, plant and equipment - unpaid invoices and other	40	17
Hawaiian Electric Company, Inc. and Subsidiaries
Supplemental disclosures of cash flow information
Interest paid	44	43
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	$ 40	$ 17