Bank segment (HEI only) - Credit Risk Profile Based on Payment Activity for Loans (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Credit risk profile based on payment activity for loans
Total past due	$ 19,751	$ 25,969
Current	5,100,913	4,817,665
Total financing receivables	5,120,664	4,843,634	$ 4,671,577
Recorded Investment greater than 90 days and accruing	0	0
Residential 1-4 family
Credit risk profile based on payment activity for loans
Total past due	4,686	8,869
Current	2,173,449	2,134,528
Total financing receivables	2,178,135	2,143,397	2,118,047
Recorded Investment greater than 90 days and accruing	0	0
Commercial real estate
Credit risk profile based on payment activity for loans
Total past due	0	0
Current	824,830	748,398
Total financing receivables	824,830	748,398	733,106
Recorded Investment greater than 90 days and accruing	0	0
Home equity line of credit
Credit risk profile based on payment activity for loans
Total past due	2,930	4,540
Current	1,089,195	973,697
Total financing receivables	1,092,125	978,237	913,052
Recorded Investment greater than 90 days and accruing	0	0
Residential land
Credit risk profile based on payment activity for loans
Total past due	25	328
Current	14,679	12,810
Total financing receivables	14,704	13,138	15,797
Recorded Investment greater than 90 days and accruing	0	0
Commercial construction
Credit risk profile based on payment activity for loans
Total past due	0	0
Current	70,605	92,264
Total financing receivables	70,605	92,264	108,273
Recorded Investment greater than 90 days and accruing	0	0
Residential construction
Credit risk profile based on payment activity for loans
Total past due	0	0
Current	11,670	14,307
Total financing receivables	11,670	14,307	14,910
Recorded Investment greater than 90 days and accruing	0	0
Commercial
Credit risk profile based on payment activity for loans
Total past due	1,560	1,144
Current	669,114	586,747
Total financing receivables	670,674	587,891	544,828
Recorded Investment greater than 90 days and accruing	0	0
Consumer
Credit risk profile based on payment activity for loans
Total past due	10,550	11,088
Current	247,371	254,914
Total financing receivables	257,921	266,002	$ 223,564
Recorded Investment greater than 90 days and accruing	0	0
30-59 days past due
Credit risk profile based on payment activity for loans
Total past due	8,864	10,440
30-59 days past due | Residential 1-4 family
Credit risk profile based on payment activity for loans
Total past due	2,588	3,757
30-59 days past due | Commercial real estate
Credit risk profile based on payment activity for loans
Total past due	0	0
30-59 days past due | Home equity line of credit
Credit risk profile based on payment activity for loans
Total past due	813	1,139
30-59 days past due | Residential land
Credit risk profile based on payment activity for loans
Total past due	0	9
30-59 days past due | Commercial construction
Credit risk profile based on payment activity for loans
Total past due	0	0
30-59 days past due | Residential construction
Credit risk profile based on payment activity for loans
Total past due	0	0
30-59 days past due | Commercial
Credit risk profile based on payment activity for loans
Total past due	1,077	315
30-59 days past due | Consumer
Credit risk profile based on payment activity for loans
Total past due	4,386	5,220
60-89 days past due
Credit risk profile based on payment activity for loans
Total past due	3,858	6,901
60-89 days past due | Residential 1-4 family
Credit risk profile based on payment activity for loans
Total past due	290	2,773
60-89 days past due | Commercial real estate
Credit risk profile based on payment activity for loans
Total past due	0	0
60-89 days past due | Home equity line of credit
Credit risk profile based on payment activity for loans
Total past due	0	681
60-89 days past due | Residential land
Credit risk profile based on payment activity for loans
Total past due	0	0
60-89 days past due | Commercial construction
Credit risk profile based on payment activity for loans
Total past due	0	0
60-89 days past due | Residential construction
Credit risk profile based on payment activity for loans
Total past due	0	0
60-89 days past due | Commercial
Credit risk profile based on payment activity for loans
Total past due	311	281
60-89 days past due | Consumer
Credit risk profile based on payment activity for loans
Total past due	3,257	3,166
Greater than 90 days
Credit risk profile based on payment activity for loans
Total past due	7,029	8,628
Greater than 90 days | Residential 1-4 family
Credit risk profile based on payment activity for loans
Total past due	1,808	2,339
Greater than 90 days | Commercial real estate
Credit risk profile based on payment activity for loans
Total past due	0	0
Greater than 90 days | Home equity line of credit
Credit risk profile based on payment activity for loans
Total past due	2,117	2,720
Greater than 90 days | Residential land
Credit risk profile based on payment activity for loans
Total past due	25	319
Greater than 90 days | Commercial construction
Credit risk profile based on payment activity for loans
Total past due	0	0
Greater than 90 days | Residential construction
Credit risk profile based on payment activity for loans
Total past due	0	0
Greater than 90 days | Commercial
Credit risk profile based on payment activity for loans
Total past due	172	548
Greater than 90 days | Consumer
Credit risk profile based on payment activity for loans
Total past due	$ 2,907	$ 2,702