Bank segment (HEI only) - Credit Risk Profile - Nonaccrual Loans (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Credit risk profile based on nonaccrual loans
With a Related ACL	$ 36,491
Without a Related ACL	10,905
Total	47,396	$ 29,736
Total troubled debt restructuring loans not included above	27,078	26,413
Commercial
Credit risk profile based on nonaccrual loans
With a Related ACL	1,819
Without a Related ACL	3,328
Total	5,147	5,947
Total troubled debt restructuring loans not included above	6,108	2,614
Consumer
Credit risk profile based on nonaccrual loans
With a Related ACL	3,935
Without a Related ACL	0
Total	3,935	5,113
Total troubled debt restructuring loans not included above	54	57
Residential 1-4 family \| Real estate
Credit risk profile based on nonaccrual loans
With a Related ACL	8,991
Without a Related ACL	2,835
Total	11,826	11,395
Total troubled debt restructuring loans not included above	7,932	9,869
Commercial real estate \| Real estate
Credit risk profile based on nonaccrual loans
With a Related ACL	15,847
Without a Related ACL	2,875
Total	18,722	195
Total troubled debt restructuring loans not included above	3,281	853
Home equity line of credit \| Real estate
Credit risk profile based on nonaccrual loans
With a Related ACL	5,791
Without a Related ACL	1,567
Total	7,358	6,638
Total troubled debt restructuring loans not included above	8,148	10,376
Residential land \| Real estate
Credit risk profile based on nonaccrual loans
With a Related ACL	108
Without a Related ACL	300
Total	408	448
Total troubled debt restructuring loans not included above	1,555	2,644
Commercial construction \| Real estate
Credit risk profile based on nonaccrual loans
With a Related ACL	0
Without a Related ACL	0
Total	0	0
Total troubled debt restructuring loans not included above	0	0
Residential construction \| Real estate
Credit risk profile based on nonaccrual loans
With a Related ACL	0
Without a Related ACL	0
Total	0	0
Total troubled debt restructuring loans not included above	$ 0	$ 0

Financing Receivable, Nonaccrual, With Allowance

No definition available.

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- Definition

Amount, after troubled debt restructuring, of modified financing receivable.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953676-111524

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- Definition

Amount of financing receivable on nonaccrual status with no allowance for credit loss.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 16
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919258-210447

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- Definition

Amount of financing receivable on nonaccrual status.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5111-111524

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 16
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919258-210447

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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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