Electric utility segment (Details 1) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
Regulatory assets
Regulatory assets	$ 575,924	$ 864,596
Regulatory liabilities
Regulatory liabilities	349,299	324,152
Hawaiian Electric Company, Inc. and Subsidiaries
Regulatory assets
Regulatory assets	575,924	864,596
Regulatory liabilities
Regulatory liabilities	349,299	324,152
Hawaiian Electric Company, Inc. and Subsidiaries \| Cost of removal in excess of salvage value
Regulatory liabilities
Regulatory liabilities	315,164	305,978
Hawaiian Electric Company, Inc. and Subsidiaries \| Retirement benefit plans, regulatory liabilities
Regulatory liabilities
Regulatory liabilities	31,546	15,563
Authorized amortization or recovery periods	5 years	5 years
Remaining amortization or recovery periods	5 years	5 years
Hawaiian Electric Company, Inc. and Subsidiaries \| Other, regulatory liabilities
Regulatory liabilities
Regulatory liabilities	2,589	2,611
Authorized amortization or recovery periods	5 years	5 years
Hawaiian Electric Company, Inc. and Subsidiaries \| Retirement benefit plans, regulatory assets
Regulatory assets
Regulatory assets	350,821	660,835
Hawaiian Electric Company, Inc. and Subsidiaries \| Income taxes, net
Regulatory assets
Regulatory assets	85,430	84,931
Hawaiian Electric Company, Inc. and Subsidiaries \| Decoupling revenue balancing account
Regulatory assets
Regulatory assets	90,386	66,076
Hawaiian Electric Company, Inc. and Subsidiaries \| Unamortized expense and premiums on retired debt and equity issuances
Regulatory assets
Regulatory assets	17,342	17,130
Hawaiian Electric Company, Inc. and Subsidiaries \| Vacation earned, but not yet taken
Regulatory assets
Regulatory assets	9,149	8,493
Authorized amortization or recovery periods	1 year	1 year
Hawaiian Electric Company, Inc. and Subsidiaries \| Postretirement benefits other than pensions
Regulatory assets
Regulatory assets	62	249
Authorized amortization or recovery periods	18 years	18 years
Remaining amortization or recovery periods	1 year	1 year
Hawaiian Electric Company, Inc. and Subsidiaries \| Other, regulatory assets
Regulatory assets
Regulatory assets	22,734	26,882
Hawaiian Electric Company, Inc. and Subsidiaries \| Maximum \| Cost of removal in excess of salvage value
Regulatory liabilities
Authorized amortization or recovery periods	60 years	60 years
Hawaiian Electric Company, Inc. and Subsidiaries \| Maximum \| Other, regulatory liabilities
Regulatory liabilities
Remaining amortization or recovery periods	2 years	2 years
Hawaiian Electric Company, Inc. and Subsidiaries \| Maximum \| Income taxes, net
Regulatory assets
Authorized amortization or recovery periods	55 years	55 years
Hawaiian Electric Company, Inc. and Subsidiaries \| Maximum \| Decoupling revenue balancing account
Regulatory assets
Authorized amortization or recovery periods	2 years	2 years
Hawaiian Electric Company, Inc. and Subsidiaries \| Maximum \| Unamortized expense and premiums on retired debt and equity issuances
Regulatory assets
Authorized amortization or recovery periods	30 years	30 years
Remaining amortization or recovery periods	20 years	20 years
Hawaiian Electric Company, Inc. and Subsidiaries \| Maximum \| Other, regulatory assets
Regulatory assets
Authorized amortization or recovery periods	50 years	50 years
Remaining amortization or recovery periods	47 years	47 years
Hawaiian Electric Company, Inc. and Subsidiaries \| Minimum \| Cost of removal in excess of salvage value
Regulatory liabilities
Authorized amortization or recovery periods	1 year	1 year
Hawaiian Electric Company, Inc. and Subsidiaries \| Minimum \| Other, regulatory liabilities
Regulatory liabilities
Remaining amortization or recovery periods	1 year	1 year
Hawaiian Electric Company, Inc. and Subsidiaries \| Minimum \| Income taxes, net
Regulatory assets
Authorized amortization or recovery periods	1 year	1 year
Hawaiian Electric Company, Inc. and Subsidiaries \| Minimum \| Decoupling revenue balancing account
Regulatory assets
Authorized amortization or recovery periods	1 year	1 year
Hawaiian Electric Company, Inc. and Subsidiaries \| Minimum \| Unamortized expense and premiums on retired debt and equity issuances
Regulatory assets
Authorized amortization or recovery periods	14 years	14 years
Remaining amortization or recovery periods	2 years	2 years
Hawaiian Electric Company, Inc. and Subsidiaries \| Minimum \| Other, regulatory assets
Regulatory assets
Authorized amortization or recovery periods	1 year	1 year
Remaining amortization or recovery periods	1 year	1 year
Hawaiian Electric Company, Inc. and Subsidiaries \| Current assets
Regulatory assets
Regulatory assets	69,738	51,267
Hawaiian Electric Company, Inc. and Subsidiaries \| Long-term assets
Regulatory assets
Regulatory assets	506,186	813,329
Hawaiian Electric Company, Inc. and Subsidiaries \| Current liabilities
Regulatory liabilities
Regulatory liabilities	1,916	1,212
Hawaiian Electric Company, Inc. and Subsidiaries \| Long-term liabilities
Regulatory liabilities
Regulatory liabilities	$ 347,383	$ 322,940