Bank segment (HEI only) - Credit Risk Profile Based on Payment Activity for Loans (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Credit risk profile based on payment activity for loans
Total past due	$ 23,603	$ 23,102
Current	4,647,974	4,720,517
Total financing receivables	4,671,577	4,743,619	$ 4,622,068
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	8,318	11,310
Current	2,109,729	2,036,741
Total financing receivables	2,118,047	2,048,051	2,069,665
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	2,416
Current	733,106	797,979
Total financing receivables	733,106	800,395	690,561
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	2,590	2,986
Current	910,462	860,177
Total financing receivables	913,052	863,163	846,294
Recorded Investment greater than 90 days and accruing	0	0
Residential land
Credit risk profile based on payment activity for loans
Total past due	648	255
Current	15,149	18,634
Total financing receivables	15,797	18,889	18,229
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	108,273	126,768
Total financing receivables	108,273	126,768	100,796
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	14,910	16,080
Total financing receivables	14,910	16,080	14,089
Recorded Investment greater than 90 days and accruing	0	0
Commercial
Credit risk profile based on payment activity for loans
Total past due	4,580	2,226
Current	540,248	689,825
Total financing receivables	544,828	692,051	758,659
Recorded Investment greater than 90 days and accruing	0	0
Consumer
Credit risk profile based on payment activity for loans
Total past due	7,467	3,909
Current	216,097	174,313
Total financing receivables	223,564	178,222	$ 123,775
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	7,237	11,504
30-59 days past due \| Residential 1-4 family
Credit risk profile based on payment activity for loans
Total past due	1,532	5,467
30-59 days past due \| Commercial real estate
Credit risk profile based on payment activity for loans
Total past due	0	2,416
30-59 days past due \| Home equity line of credit
Credit risk profile based on payment activity for loans
Total past due	425	1,263
30-59 days past due \| Residential land
Credit risk profile based on payment activity for loans
Total past due	23	0
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	1,825	413
30-59 days past due \| Consumer
Credit risk profile based on payment activity for loans
Total past due	3,432	1,945
60-89 days past due
Credit risk profile based on payment activity for loans
Total past due	6,013	4,230
60-89 days past due \| Residential 1-4 family
Credit risk profile based on payment activity for loans
Total past due	1,715	2,338
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	114	381
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	2,025	510
60-89 days past due \| Consumer
Credit risk profile based on payment activity for loans
Total past due	2,159	1,001
Greater than 90 days
Credit risk profile based on payment activity for loans
Total past due	10,353	7,368
Greater than 90 days \| Residential 1-4 family
Credit risk profile based on payment activity for loans
Total past due	5,071	3,505
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	2,051	1,342
Greater than 90 days \| Residential land
Credit risk profile based on payment activity for loans
Total past due	625	255
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	730	1,303
Greater than 90 days \| Consumer
Credit risk profile based on payment activity for loans
Total past due	$ 1,876	$ 963

Recorded investment in financing receivables that are 90 days or more past due and still accruing.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Recorded Investment
-URI http://asc.fasb.org/extlink&oid=65880944

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5111-111524

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- Definition

Financing receivables that are current.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7A
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953401-111524

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- Definition

Recorded Investment in financing receivables that are past due at the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Recorded Investment
-URI http://asc.fasb.org/extlink&oid=65880944

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7A
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953401-111524

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- Definition

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+ References

No definition available.

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- Definition

Net amount of the investment in a contractual right to receive money on demand or on fixed or determinable dates that is recognized as an asset in the creditor's statement of financial position. Examples include, but are not limited to, credit card receivables, notes receivable and receivables relating to lessor's rights to payments from leases other than operating leases that have been recorded as assets. Excludes trade accounts receivable with contractual maturity of one year or less and arose from the sale of goods or services.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.3)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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