Bank segment (HEI only) - Loan Modifications (Details) $ in Thousands	12 Months Ended
Dec. 31, 2016 USD ($) contract	Dec. 31, 2015 USD ($) contract	Dec. 31, 2014
Loan modifications determined to be troubled debt restructurings
Commitments to Borrowers whose Loan Terms are Impaired or Modified under Troubled Debt Restructuring	$ 2,600
Troubled debt restructurings real estate loans
Loan modifications determined to be troubled debt restructurings
Number of contracts \| contract	67	68
Pre-modification outstanding recorded investment	$ 26,937	$ 10,020
Post-modification outstanding recorded investment	27,052	10,094
Net increase in ALLL	$ 1,756	$ 943
Minimum period of payment default of loans determined to be TDRs	90 days	90 days	90 days
Troubled debt restructurings real estate loans \| Residential 1-4 family
Loan modifications determined to be troubled debt restructurings
Number of contracts \| contract	14	19
Pre-modification outstanding recorded investment	$ 3,131	$ 3,594
Post-modification outstanding recorded investment	3,245	3,668
Net increase in ALLL	$ 337	$ 87
Troubled debt restructurings real estate loans \| Commercial real estate
Loan modifications determined to be troubled debt restructurings
Number of contracts \| contract	0	1
Pre-modification outstanding recorded investment	$ 0	$ 1,500
Post-modification outstanding recorded investment	0	1,500
Net increase in ALLL	$ 0	$ 0
Troubled debt restructurings real estate loans \| Home equity line of credit
Loan modifications determined to be troubled debt restructurings
Number of contracts \| contract	36	39
Pre-modification outstanding recorded investment	$ 3,337	$ 2,441
Post-modification outstanding recorded investment	3,337	2,441
Net increase in ALLL	$ 554	$ 370
Troubled debt restructurings real estate loans \| Residential land
Loan modifications determined to be troubled debt restructurings
Number of contracts \| contract	2	1
Pre-modification outstanding recorded investment	$ 203	$ 218
Post-modification outstanding recorded investment	204	218
Net increase in ALLL	$ 0	$ 0
Troubled debt restructurings real estate loans \| Commercial construction
Loan modifications determined to be troubled debt restructurings
Number of contracts \| contract	0	0
Pre-modification outstanding recorded investment	$ 0	$ 0
Post-modification outstanding recorded investment	0	0
Net increase in ALLL	$ 0	$ 0
Troubled debt restructurings real estate loans \| Residential construction
Loan modifications determined to be troubled debt restructurings
Number of contracts \| contract	0	0
Pre-modification outstanding recorded investment	$ 0	$ 0
Post-modification outstanding recorded investment	0	0
Net increase in ALLL	$ 0	$ 0
Troubled debt restructurings real estate loans \| Commercial loans
Loan modifications determined to be troubled debt restructurings
Number of contracts \| contract	15	8
Pre-modification outstanding recorded investment	$ 20,266	$ 2,267
Post-modification outstanding recorded investment	20,266	2,267
Net increase in ALLL	$ 865	$ 486
Troubled debt restructurings real estate loans \| Consumer loans
Loan modifications determined to be troubled debt restructurings
Number of contracts \| contract	0	0
Pre-modification outstanding recorded investment	$ 0	$ 0
Post-modification outstanding recorded investment	0	0
Net increase in ALLL	$ 0	$ 0
Troubled debt restructurings that subsequently defaulted
Loan modifications determined to be troubled debt restructurings
Number of contracts \| contract	2	2
Recorded investment	$ 263	$ 1,062
Troubled debt restructurings that subsequently defaulted \| Residential 1-4 family
Loan modifications determined to be troubled debt restructurings
Number of contracts \| contract	1	0
Recorded investment	$ 239	$ 0
Troubled debt restructurings that subsequently defaulted \| Commercial real estate
Loan modifications determined to be troubled debt restructurings
Number of contracts \| contract	0	0
Recorded investment	$ 0	$ 0
Troubled debt restructurings that subsequently defaulted \| Home equity line of credit
Loan modifications determined to be troubled debt restructurings
Number of contracts \| contract	0	1
Recorded investment	$ 0	$ 6
Troubled debt restructurings that subsequently defaulted \| Residential land
Loan modifications determined to be troubled debt restructurings
Number of contracts \| contract	0	0
Recorded investment	$ 0	$ 0
Troubled debt restructurings that subsequently defaulted \| Commercial construction
Loan modifications determined to be troubled debt restructurings
Number of contracts \| contract	0	0
Recorded investment	$ 0	$ 0
Troubled debt restructurings that subsequently defaulted \| Residential construction
Loan modifications determined to be troubled debt restructurings
Number of contracts \| contract	0	0
Recorded investment	$ 0	$ 0
Troubled debt restructurings that subsequently defaulted \| Commercial loans
Loan modifications determined to be troubled debt restructurings
Number of contracts \| contract	1	1
Recorded investment	$ 24	$ 1,056
Troubled debt restructurings that subsequently defaulted \| Consumer loans
Loan modifications determined to be troubled debt restructurings
Number of contracts \| contract	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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Period Type:	instant

- Definition

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

+ References

No definition available.

+ Details

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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.

+ Details

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- Definition

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

+ References

No definition available.

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- Definition

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

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Recorded Investment
-URI http://asc.fasb.org/extlink&oid=65880944

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