Bank segment (HEI only) - Collateral-Dependent Loans (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Financing Receivable, Nonaccrual [Line Items]
Consumer mortgage loans collateralized by residential real estate property in foreclosure process	$ 3,400	$ 4,200
Residential real estate property | Real estate | Residential 1-4 family
Financing Receivable, Nonaccrual [Line Items]
Amortized cost	2,272	3,959
Residential real estate property | Real estate | Home equity  line of credit
Financing Receivable, Nonaccrual [Line Items]
Amortized cost	1,135	1,425
Residential real estate property | Real estate | Residential land
Financing Receivable, Nonaccrual [Line Items]
Amortized cost	0	0
Commercial real estate | Real estate | Commercial real estate
Financing Receivable, Nonaccrual [Line Items]
Amortized cost	11,048	0
Business Assets | Commercial
Financing Receivable, Nonaccrual [Line Items]
Amortized cost	301	0
Collateral Pledged
Financing Receivable, Nonaccrual [Line Items]
Amortized cost	14,756	5,384
Collateral Pledged | Real estate
Financing Receivable, Nonaccrual [Line Items]
Amortized cost	$ 14,455	$ 5,384