v3.26.1
Electric utility segment - Schedule of Condensed Consolidating Statement of Cash Flows (Details) - USD ($)
$ in Thousands
 6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Cash flows from operating activities    
Net cash provided by (used in) operating activities $ (350,369) $ 184,416
Cash flows from investing activities    
Capital expenditures (242,090) (161,493)
Other 2,023 3,222
Net cash used in investing activities (240,067) (152,490)
Cash flows from financing activities    
Repayment of long-term debt (145,085) (630,808)
Other (6,147) (5,958)
Net cash used in financing activities (151,360) (637,890)
Net decrease in cash, cash equivalents and restricted cash (741,796) (605,964)
Cash and cash equivalents, beginning of period 501,778  
Cash and cash equivalents, end of period 238,732 154,285
Hawaiian Electric consolidated    
Cash flows from operating activities    
Net cash provided by (used in) operating activities 91,493 216,246
Cash flows from investing activities    
Capital expenditures (241,810) (159,950)
Advances to affiliates 0 0
Other 2,113 5,151
Net cash used in investing activities (239,697) (154,799)
Cash flows from financing activities    
Common stock dividends (21,000) (10,000)
Preferred stock dividends of Hawaiian Electric and subsidiaries 0 (998)
Proceeds from capital contribution from parent 0 540
Net increase in short-term borrowings from affiliate 0 0
Repayment of long-term debt (125,000) (123,000)
Payments of obligations under finance leases (5,631) (4,659)
Other (126) (1,049)
Net cash used in financing activities (151,757) (139,166)
Net decrease in cash, cash equivalents and restricted cash (299,961) (77,719)
Cash and cash equivalents, beginning of period 486,220 184,148
Cash and cash equivalents, end of period 186,259 106,429
Consolidating adjustments | Hawaiian Electric consolidated    
Cash flows from operating activities    
Net cash provided by (used in) operating activities (2,119) (971)
Cash flows from investing activities    
Capital expenditures 0 0
Advances to affiliates 94,500 7,000
Other 2,119 971
Net cash used in investing activities 96,619 7,971
Cash flows from financing activities    
Common stock dividends 0 0
Preferred stock dividends of Hawaiian Electric and subsidiaries   0
Proceeds from capital contribution from parent   0
Net increase in short-term borrowings from affiliate (94,500) (7,000)
Repayment of long-term debt 0 0
Payments of obligations under finance leases 0 0
Other 0 0
Net cash used in financing activities (94,500) (7,000)
Net decrease in cash, cash equivalents and restricted cash 0 0
Cash and cash equivalents, beginning of period 0 0
Cash and cash equivalents, end of period 0 0
Hawaiian Electric | Reportable Legal Entities | Hawaiian Electric consolidated    
Cash flows from operating activities    
Net cash provided by (used in) operating activities 68,611 147,248
Cash flows from investing activities    
Capital expenditures (169,026) (86,012)
Advances to affiliates (94,500) (7,000)
Other 1,246 3,164
Net cash used in investing activities (262,280) (89,848)
Cash flows from financing activities    
Common stock dividends (21,000) (10,000)
Preferred stock dividends of Hawaiian Electric and subsidiaries   (998)
Proceeds from capital contribution from parent   540
Net increase in short-term borrowings from affiliate 0 0
Repayment of long-term debt (62,000) (123,000)
Payments of obligations under finance leases (4,811) (3,982)
Other (126) (752)
Net cash used in financing activities (87,937) (138,192)
Net decrease in cash, cash equivalents and restricted cash (281,606) (80,792)
Cash and cash equivalents, beginning of period 396,215 118,367
Cash and cash equivalents, end of period 114,609 37,575
Hawaii Electric Light | Reportable Legal Entities | Hawaiian Electric consolidated    
Cash flows from operating activities    
Net cash provided by (used in) operating activities 23,098 37,461
Cash flows from investing activities    
Capital expenditures (29,550) (29,553)
Advances to affiliates 0 0
Other (261) 343
Net cash used in investing activities (29,811) (29,210)
Cash flows from financing activities    
Common stock dividends 0 0
Preferred stock dividends of Hawaiian Electric and subsidiaries   0
Proceeds from capital contribution from parent   0
Net increase in short-term borrowings from affiliate 0 0
Repayment of long-term debt (8,000) 0
Payments of obligations under finance leases (537) (364)
Other 0 (87)
Net cash used in financing activities (8,537) (451)
Net decrease in cash, cash equivalents and restricted cash (15,250) 7,800
Cash and cash equivalents, beginning of period 56,563 31,534
Cash and cash equivalents, end of period 41,313 39,334
Maui Electric | Reportable Legal Entities | Hawaiian Electric consolidated    
Cash flows from operating activities    
Net cash provided by (used in) operating activities 2,080 28,864
Cash flows from investing activities    
Capital expenditures (43,234) (44,385)
Advances to affiliates 0 0
Other (991) 673
Net cash used in investing activities (44,225) (43,712)
Cash flows from financing activities    
Common stock dividends 0 0
Preferred stock dividends of Hawaiian Electric and subsidiaries   0
Proceeds from capital contribution from parent   0
Net increase in short-term borrowings from affiliate 94,500 7,000
Repayment of long-term debt (55,000) 0
Payments of obligations under finance leases (283) (313)
Other 0 (210)
Net cash used in financing activities 39,217 6,477
Net decrease in cash, cash equivalents and restricted cash (2,928) (8,371)
Cash and cash equivalents, beginning of period 8,572 16,456
Cash and cash equivalents, end of period 5,644 8,085
Other subsidiaries | Reportable Legal Entities | Hawaiian Electric consolidated    
Cash flows from operating activities    
Net cash provided by (used in) operating activities (177) 3,644
Cash flows from investing activities    
Capital expenditures 0 0
Advances to affiliates 0 0
Other 0 0
Net cash used in investing activities 0 0
Cash flows from financing activities    
Common stock dividends 0 0
Preferred stock dividends of Hawaiian Electric and subsidiaries   0
Proceeds from capital contribution from parent   0
Net increase in short-term borrowings from affiliate 0 0
Repayment of long-term debt 0 0
Payments of obligations under finance leases 0 0
Other 0 0
Net cash used in financing activities 0 0
Net decrease in cash, cash equivalents and restricted cash (177) 3,644
Cash and cash equivalents, beginning of period 24,870 17,791
Cash and cash equivalents, end of period $ 24,693 $ 21,435