Bank segment (HEI only) - Carrying Amount of Impaired Loans (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2019 USD ($)
Recorded investment
With no related allowance recorded	$ 14,037
With an allowance recorded	26,700
Total	40,737
Unpaid principal balance
With no related allowance recorded	15,123
With an allowance recorded	26,762
Total	41,885
Related allowance
Total	2,691
Average recorded investment
With no related allowance recorded	17,422
With an allowance recorded	27,972
Total	45,394
Interest income recognized
With no related allowance recorded	1,400
With an allowance recorded	1,119
Total	2,519
Residential 1-4 family
Recorded investment
With no related allowance recorded	6,817
With an allowance recorded	8,783
Total	15,600
Unpaid principal balance
With no related allowance recorded	7,207
With an allowance recorded	8,835
Total	16,042
Related allowance
Total	898
Average recorded investment
With no related allowance recorded	8,169
With an allowance recorded	8,390
Total	16,559
Interest income recognized
With no related allowance recorded	907
With an allowance recorded	359
Total	1,266
Commercial real estate
Recorded investment
With no related allowance recorded	195
With an allowance recorded	853
Total	1,048
Unpaid principal balance
With no related allowance recorded	200
With an allowance recorded	853
Total	1,053
Related allowance
Total	2
Average recorded investment
With no related allowance recorded	16
With an allowance recorded	886
Total	902
Interest income recognized
With no related allowance recorded	0
With an allowance recorded	37
Total	37
Home equity line of credit
Recorded investment
With no related allowance recorded	1,984
With an allowance recorded	10,089
Total	12,073
Unpaid principal balance
With no related allowance recorded	2,135
With an allowance recorded	10,099
Total	12,234
Related allowance
Total	322
Average recorded investment
With no related allowance recorded	2,020
With an allowance recorded	11,319
Total	13,339
Interest income recognized
With no related allowance recorded	84
With an allowance recorded	567
Total	651
Residential land
Recorded investment
With no related allowance recorded	3,091
With an allowance recorded	0
Total	3,091
Unpaid principal balance
With no related allowance recorded	3,294
With an allowance recorded	0
Total	3,294
Related allowance
Total	0
Average recorded investment
With no related allowance recorded	2,662
With an allowance recorded	27
Total	2,689
Interest income recognized
With no related allowance recorded	129
With an allowance recorded	0
Total	129
Commercial construction
Recorded investment
With no related allowance recorded	0
With an allowance recorded	0
Total	0
Unpaid principal balance
With no related allowance recorded	0
With an allowance recorded	0
Total	0
Related allowance
Total	0
Average recorded investment
With no related allowance recorded	0
With an allowance recorded	0
Total	0
Interest income recognized
With no related allowance recorded	0
With an allowance recorded	0
Total	0
Residential construction
Recorded investment
With no related allowance recorded	0
With an allowance recorded	0
Total	0
Unpaid principal balance
With no related allowance recorded	0
With an allowance recorded	0
Total	0
Related allowance
Total	0
Average recorded investment
With no related allowance recorded	0
With an allowance recorded	0
Total	0
Interest income recognized
With no related allowance recorded	0
With an allowance recorded	0
Total	0
Commercial
Recorded investment
With no related allowance recorded	1,948
With an allowance recorded	6,470
Total	8,418
Unpaid principal balance
With no related allowance recorded	2,285
With an allowance recorded	6,470
Total	8,755
Related allowance
Total	1,015
Average recorded investment
With no related allowance recorded	4,534
With an allowance recorded	6,990
Total	11,524
Interest income recognized
With no related allowance recorded	276
With an allowance recorded	132
Total	408
Consumer
Recorded investment
With no related allowance recorded	2
With an allowance recorded	505
Total	507
Unpaid principal balance
With no related allowance recorded	2
With an allowance recorded	505
Total	507
Related allowance
Total	454
Average recorded investment
With no related allowance recorded	21
With an allowance recorded	360
Total	381
Interest income recognized
With no related allowance recorded	4
With an allowance recorded	24
Total	$ 28