Cash flows (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Supplemental disclosures of cash flow information
Interest paid	$ 20	$ 21
Income taxes paid/(refunded)	(18)	(3)
Supplemental disclosures of noncash activities
Common stock dividends reinvested in HEI common stock	0	6
Increases in common stock related to director and officer compensatory plans	1	0
Real estate acquired in settlement of loans	1	1
Obligations to fund low income housing investments	10	0
Additions to electric utility property, plant and equipment - unpaid invoices and other	9	3
Hawaiian Electric Company, Inc. and Subsidiaries
Supplemental disclosures of cash flow information
Interest paid	13	14
Income taxes paid/(refunded)	(8)	(26)
Supplemental disclosures of noncash activities
Additions to electric utility property, plant and equipment - unpaid invoices and other	$ 9	$ 3