Consolidated Statements of Cash Flows - HECO - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Cash flows from operating activities
Net income	$ 219,772,000	$ 203,664,000	$ 167,187,000
Adjustments to reconcile net income to net cash provided by operating activities
Depreciation of property, plant and equipment	229,858,000	214,036,000	200,658,000
Other amortization	48,255,000	41,593,000	21,340,000
Deferred income taxes	(15,085,000)	(9,368,000)	37,835,000
Allowance for equity funds used during construction	(11,987,000)	(10,877,000)	(12,483,000)
Other	10,822,000	(4,219,000)	(3,324,000)
Changes in assets and liabilities
Decrease (increase) in fuel oil stock	(11,493,000)	7,054,000	(20,794,000)
Decrease (increase) in regulatory assets	71,262,000	9,252,000	(17,256,000)
Change in prepaid and accrued income taxes, tax credits and revenue taxes	(27,538,000)	29,429,000	20,685,000
Increase (decrease) in defined benefit pension and other postretirement benefit plans liability	(4,482,000)	20,871,000	882,000
Change in other assets and liabilities	(34,724,000)	15,488,000	(25,551,000)
Net cash provided by operating activities	512,470,000	499,312,000	420,441,000
Cash flows from investing activities
Capital expenditures	(457,520,000)	(537,369,000)	(495,187,000)
Other, net	13,292,000	14,534,000	7,487,000
Net cash used in investing activities	(541,709,000)	(792,059,000)	(815,299,000)
Cash flows from financing activities
Common stock dividends	(139,463,000)	(134,987,000)	(134,873,000)
Proceeds from issuance of long-term debt	289,349,000	250,000,000	532,325,000
Repayment of long-term debt and funds transferred for repayment of long-term debt	(287,285,000)	(53,887,000)	(465,000,000)
Net increase (decrease) in short-term borrowings from non-affiliates and affiliate with original maturities of three months or less	86,718,000	(18,999,000)	67,992,000
Repayment of short-term debt	(50,000,000)	(50,000,000)	(75,000,000)
Other	(1,836,000)	(1,603,000)	(6,349,000)
Net cash used in financing activities	87,716,000	200,074,000	378,287,000
Net decrease in cash and equivalents	58,477,000	(92,673,000)	(16,571,000)
Cash, cash equivalents and restricted cash, January 1	169,208,000	261,881,000	278,452,000
Cash, cash equivalents and restricted cash, December 31	227,685,000	169,208,000	261,881,000
Less: Restricted cash	(30,872,000)	0	0
Cash and cash equivalents	196,813,000	169,208,000	261,881,000
Hawaiian Electric Company, Inc. and Subsidiaries
Cash flows from operating activities
Net income	158,835,000	145,648,000	121,946,000
Adjustments to reconcile net income to net cash provided by operating activities
Depreciation of property, plant and equipment	215,731,000	203,626,000	192,784,000
Other amortization	29,631,000	26,602,000	8,498,000
Deferred income taxes	(16,284,000)	(7,982,000)	38,037,000
Income tax credits, net	27,259,000	(99,000)	(52,000)
State refundable credit	(8,369,000)	(6,239,000)	(2,251,000)
Allowance for equity funds used during construction	(11,987,000)	(10,877,000)	(12,483,000)
Other	200,000	4,768,000	1,237,000
Changes in assets and liabilities
Decrease (increase) in accounts receivable	20,956,000	(50,917,000)	2,914,000
Decrease (increase) in accrued unbilled revenues	4,511,000	(14,684,000)	(15,361,000)
Decrease (increase) in fuel oil stock	(12,002,000)	6,938,000	(20,443,000)
Increase in materials and supplies	(5,498,000)	(807,000)	(718,000)
Decrease (increase) in regulatory assets	71,262,000	9,252,000	(17,256,000)
Increase in regulatory liabilities	1,953,000	37,358,000	3,602,000
Increase (decrease) in accounts payable	(2,051,000)	24,358,000	25,734,000
Change in prepaid and accrued income taxes, tax credits and revenue taxes	(28,523,000)	25,036,000	29,862,000
Increase (decrease) in defined benefit pension and other postretirement benefit plans liability	(4,448,000)	18,746,000	604,000
Change in other assets and liabilities	(17,220,000)	(17,114,000)	(21,468,000)
Net cash provided by operating activities	423,956,000	393,613,000	335,186,000
Cash flows from investing activities
Capital expenditures	(419,898,000)	(415,264,000)	(376,865,000)
Other, net	11,374,000	10,082,000	4,578,000
Net cash used in investing activities	(408,524,000)	(405,182,000)	(372,287,000)
Cash flows from financing activities
Common stock dividends	(101,252,000)	(103,305,000)	(87,767,000)
Preferred stock dividends of Hawaiian Electric and subsidiaries	(1,995,000)	(1,995,000)	(1,995,000)
Proceeds from issuance of common stock	35,500,000	70,700,000	14,000,000
Proceeds from issuance of long-term debt	280,000,000	100,000,000	315,000,000
Repayment of long-term debt and funds transferred for repayment of long-term debt	(283,546,000)	(50,000,000)	(265,000,000)
Net increase (decrease) in short-term borrowings from non-affiliates and affiliate with original maturities of three months or less	38,987,000	(4,999,000)	4,999,000
Proceeds from issuance of short-term debt	75,000,000	25,000,000	0
Repayment of short-term debt	(50,000,000)	0	0
Other	(2,109,000)	(472,000)	(3,905,000)
Net cash used in financing activities	(9,415,000)	34,929,000	(24,668,000)
Net decrease in cash and equivalents	6,017,000	23,360,000	(61,769,000)
Cash, cash equivalents and restricted cash, January 1	35,877,000	12,517,000	74,286,000
Cash, cash equivalents and restricted cash, December 31	41,894,000	35,877,000	12,517,000
Less: Restricted cash	(30,872,000)	0	0
Cash and cash equivalents	$ 11,022,000	$ 35,877,000	$ 12,517,000