Bank segment (HEI only) Loan Modifications (Details) (USD $)	12 Months Ended
Dec. 31, 2014 contract	Dec. 31, 2013 contract	Dec. 31, 2012
Loan modifications determined to be troubled debt restructurings
Commitments to Borrowers whose Loan Terms are Impaired or Modified under Troubled Debt Restructuring	$ 500,000
Troubled debt restructurings real estate loans
Loan modifications determined to be troubled debt restructurings
Number of contracts	71	66
Pre-modification outstanding recorded investment	19,313,000	20,374,000
Post-modification outstanding recorded investment	19,370,000	20,199,000
Net increase in ALLL	460,000	522,000
Minimum period of payment default of loans determined to be TDRs	90 days	90 days	90 days
Troubled debt restructurings that subsequently defaulted
Loan modifications determined to be troubled debt restructurings
Number of contracts	2	3
Recorded investment	404,000	727,000
Residential 1-4 family \| Troubled debt restructurings real estate loans
Loan modifications determined to be troubled debt restructurings
Number of contracts	38	34
Pre-modification outstanding recorded investment	10,680,000	8,876,000
Post-modification outstanding recorded investment	10,737,000	8,957,000
Net increase in ALLL	163,000	297,000
Residential 1-4 family \| Troubled debt restructurings that subsequently defaulted
Loan modifications determined to be troubled debt restructurings
Number of contracts	1	0
Recorded investment	390,000	0
Commercial real estate \| Troubled debt restructurings real estate loans
Loan modifications determined to be troubled debt restructurings
Number of contracts	0	0
Pre-modification outstanding recorded investment	0	0
Post-modification outstanding recorded investment	0	0
Net increase in ALLL	0	0
Commercial real estate \| Troubled debt restructurings that subsequently defaulted
Loan modifications determined to be troubled debt restructurings
Number of contracts	0	0
Recorded investment	0	0
Home equity line of credit \| Troubled debt restructurings real estate loans
Loan modifications determined to be troubled debt restructurings
Number of contracts	8	5
Pre-modification outstanding recorded investment	502,000	637,000
Post-modification outstanding recorded investment	502,000	390,000
Net increase in ALLL	42,000	0
Home equity line of credit \| Troubled debt restructurings that subsequently defaulted
Loan modifications determined to be troubled debt restructurings
Number of contracts	0	1
Recorded investment	0	67,000
Residential land \| Troubled debt restructurings real estate loans
Loan modifications determined to be troubled debt restructurings
Number of contracts	18	20
Pre-modification outstanding recorded investment	4,304,000	6,215,000
Post-modification outstanding recorded investment	4,304,000	6,206,000
Net increase in ALLL	242,000	131,000
Residential land \| Troubled debt restructurings that subsequently defaulted
Loan modifications determined to be troubled debt restructurings
Number of contracts	0	0
Recorded investment	0	0
Commercial construction \| Troubled debt restructurings real estate loans
Loan modifications determined to be troubled debt restructurings
Number of contracts	0	0
Pre-modification outstanding recorded investment	0	0
Post-modification outstanding recorded investment	0	0
Net increase in ALLL	0	0
Commercial construction \| Troubled debt restructurings that subsequently defaulted
Loan modifications determined to be troubled debt restructurings
Number of contracts	0	0
Recorded investment	0	0
Residential construction \| Troubled debt restructurings real estate loans
Loan modifications determined to be troubled debt restructurings
Number of contracts	0	0
Pre-modification outstanding recorded investment	0	0
Post-modification outstanding recorded investment	0	0
Net increase in ALLL	0	0
Residential construction \| Troubled debt restructurings that subsequently defaulted
Loan modifications determined to be troubled debt restructurings
Number of contracts	0	0
Recorded investment	0	0
Commercial loans \| Troubled debt restructurings real estate loans
Loan modifications determined to be troubled debt restructurings
Number of contracts	7	7
Pre-modification outstanding recorded investment	3,827,000	4,646,000
Post-modification outstanding recorded investment	3,827,000	4,646,000
Net increase in ALLL	13,000	94,000
Commercial loans \| Troubled debt restructurings that subsequently defaulted
Loan modifications determined to be troubled debt restructurings
Number of contracts	1	2
Recorded investment	14,000	660,000
Consumer loans \| Troubled debt restructurings real estate loans
Loan modifications determined to be troubled debt restructurings
Number of contracts	0	0
Pre-modification outstanding recorded investment	0	0
Post-modification outstanding recorded investment	0	0
Net increase in ALLL	0	0
Consumer loans \| Troubled debt restructurings that subsequently defaulted
Loan modifications determined to be troubled debt restructurings
Number of contracts	0	0
Recorded investment	$ 0	$ 0

Represents the commitments to borrowers whose loan terms are impaired or modified under troubled debt restructuring.

No definition available.

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- Definition

Represents the minimum period of payment default of loans determined to be troubled debt restructurings.

+ References

No definition available.

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- Definition

The number of contracts under financing receivables that have been modified by troubled debt restructurings during the period.

+ References

No definition available.

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The amount of the outstanding recorded investment in financial receivables after the financial receivables being modified as troubled debt restructurings.

+ References

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The amount of the outstanding recorded investment in financial receivables prior to the financial receivables being modified as troubled debt restructurings.

+ References

No definition available.

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- Definition

Amount of increase (decrease) of allowance reserve for credit loss.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.7(d))

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Subparagraph d

-Article 9

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The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 40

-Section 50

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=25495931&loc=d3e18845-111554

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