Bank segment (HEI only) Carrying Amount of Impaired Loans (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Recorded investment:
With no related allowance recorded	$ 23,167	$ 16,487
With an allowance recorded	26,679	36,031
Recorded investment	49,846	52,518
Unpaid principal balance:
With no related allowance recorded	28,890	21,717
With an allowance recorded	27,119	39,185
Unpaid principal balance	56,009	60,902
Related Allowance	4,665	5,338
Average recorded investment:
With no related allowance recorded	17,592	24,631
With an allowance recorded	30,882	34,679
Average recorded investment	48,474	59,310
Interest income recognized:
With no related allowance recorded	442	882
With an allowance recorded	1,825	1,072
Interest income recognized	2,267	1,954
Residential 1-4 family
Recorded investment:
With no related allowance recorded	11,654	9,708
With an allowance recorded	11,327	6,216
Recorded investment	22,981	15,924
Unpaid principal balance:
With no related allowance recorded	12,987	12,144
With an allowance recorded	11,347	6,236
Unpaid principal balance	24,334	18,380
Related Allowance	951	642
Average recorded investment:
With no related allowance recorded	9,056	11,674
With an allowance recorded	8,822	6,455
Average recorded investment	17,878	18,129
Interest income recognized:
With no related allowance recorded	227	386
With an allowance recorded	419	372
Interest income recognized	646	758
Commercial real estate
Recorded investment:
With no related allowance recorded	571	0
With an allowance recorded	4,541	4,604
Recorded investment	5,112	4,604
Unpaid principal balance:
With no related allowance recorded	626	0
With an allowance recorded	4,541	4,686
Unpaid principal balance	5,167	4,686
Related Allowance	1,845	1,118
Average recorded investment:
With no related allowance recorded	194	802
With an allowance recorded	3,415	5,745
Average recorded investment	3,609	6,547
Interest income recognized:
With no related allowance recorded	0	0
With an allowance recorded	478	152
Interest income recognized	478	152
Home equity line of credit
Recorded investment:
With no related allowance recorded	363	672
With an allowance recorded	416	0
Recorded investment	779	672
Unpaid principal balance:
With no related allowance recorded	606	1,227
With an allowance recorded	420	0
Unpaid principal balance	1,026	1,227
Related Allowance	46	0
Average recorded investment:
With no related allowance recorded	402	623
With an allowance recorded	132	0
Average recorded investment	534	623
Interest income recognized:
With no related allowance recorded	5	2
With an allowance recorded	6	0
Interest income recognized	11	2
Residential land
Recorded investment:
With no related allowance recorded	2,344	2,622
With an allowance recorded	5,506	7,452
Recorded investment	7,850	10,074
Unpaid principal balance:
With no related allowance recorded	3,200	3,612
With an allowance recorded	5,584	7,623
Unpaid principal balance	8,784	11,235
Related Allowance	1,057	1,332
Average recorded investment:
With no related allowance recorded	2,728	6,675
With an allowance recorded	6,415	6,844
Average recorded investment	9,143	13,519
Interest income recognized:
With no related allowance recorded	172	482
With an allowance recorded	484	409
Interest income recognized	656	891
Commercial construction
Recorded investment:
With no related allowance recorded	0	0
With an allowance recorded	0	0
Recorded investment	0	0
Unpaid principal balance:
With no related allowance recorded	0	0
With an allowance recorded	0	0
Unpaid principal balance	0	0
Related Allowance	0	0
Average recorded investment:
With no related allowance recorded	0	0
With an allowance recorded	0	0
Average recorded investment	0	0
Interest income recognized:
With no related allowance recorded	0	0
With an allowance recorded	0	0
Interest income recognized	0	0
Residential construction
Recorded investment:
With no related allowance recorded	0	0
With an allowance recorded	0	0
Recorded investment	0	0
Unpaid principal balance:
With no related allowance recorded	0	0
With an allowance recorded	0	0
Unpaid principal balance	0	0
Related Allowance	0	0
Average recorded investment:
With no related allowance recorded	0	0
With an allowance recorded	0	0
Average recorded investment	0	0
Interest income recognized:
With no related allowance recorded	0	0
With an allowance recorded	0	0
Interest income recognized	0	0
Commercial loans
Recorded investment:
With no related allowance recorded	8,235	3,466
With an allowance recorded	4,873	17,759
Recorded investment	13,108	21,225
Unpaid principal balance:
With no related allowance recorded	11,471	4,715
With an allowance recorded	5,211	20,640
Unpaid principal balance	16,682	25,355
Related Allowance	760	2,246
Average recorded investment:
With no related allowance recorded	5,204	4,837
With an allowance recorded	12,089	15,635
Average recorded investment	17,293	20,472
Interest income recognized:
With no related allowance recorded	38	12
With an allowance recorded	438	139
Interest income recognized	476	151
Consumer loans
Recorded investment:
With no related allowance recorded	0	19
With an allowance recorded	16	0
Recorded investment	16	19
Unpaid principal balance:
With no related allowance recorded	0	19
With an allowance recorded	16	0
Unpaid principal balance	16	19
Related Allowance	6	0
Average recorded investment:
With no related allowance recorded	8	20
With an allowance recorded	9	0
Average recorded investment	17	20
Interest income recognized:
With no related allowance recorded	0	0
With an allowance recorded	0	0
Interest income recognized	$ 0	$ 0

Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=d3e5212-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 17

-URI http://asc.fasb.org/extlink&oid=35738203&loc=d3e5258-111524

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Section 50

-Paragraph 14A

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