Name:	htbk_BusinessCombinationAcquiredReceivablesEstimatedUncollectibleImpairedLoans
Namespace Prefix:	htbk_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

For receivables acquired in a business combination, excluding certain loans and debt securities acquired in a transfer (as defined), this element represents the fair value of nonimpaired loans acquired.

No definition available.

Name:	htbk_BusinessCombinationAcquiredReceivablesFairValueNonimpairedLoans
Namespace Prefix:	htbk_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

For receivables acquired in a business combination, excluding certain loans and debt securities acquired in a transfer (as defined), this element represents the gross contractual amounts of impaired loans.

No definition available.

Name:	htbk_BusinessCombinationAcquiredReceivablesGrossContractualAmountImpairedLoans
Namespace Prefix:	htbk_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

For receivables acquired in a business combination, excluding certain loans and debt securities acquired in a transfer (as defined), this element represents the gross contractual nonimpaired loans.

No definition available.

Name:	htbk_BusinessCombinationAcquiredReceivablesGrossContractualAmountNonimpairedLoans
Namespace Prefix:	htbk_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Represents contractual cash flows not expected to be collected on impaired loans as a percent of the gross contractual amount.

No definition available.

Name:	htbk_BusinessCombinationAcquiredReceivablesImpairedLoansEstimatedUncollectiblePercentageOfGrossContractualAmount
Namespace Prefix:	htbk_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

Represents the number of impaired loans acquired in a business combination.

No definition available.

Name:	htbk_BusinessCombinationAcquiredReceivablesImpairedLoansNumber
Namespace Prefix:	htbk_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

Represents the purchase discount on nonimpaired loans receivable acquired in a business combination.

No definition available.

Name:	htbk_BusinessCombinationAcquiredReceivablesPurchaseDiscountNonimpairedLoans
Namespace Prefix:	htbk_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Represents the purchase discount on nonimpaired loans receivable acquired in a business combination as a percentage of gross outstanding principal balances.

No definition available.

Name:	htbk_BusinessCombinationAcquiredReceivablesPurchaseDiscountNonimpairedLoansPercentage
Namespace Prefix:	htbk_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- References

No definition available.

Name:	us-gaap_BusinessCombinationAcquiredReceivablesAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- References

No definition available.

Name:	us-gaap_BusinessCombinationGoodwillAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=64834752&loc=SL49117168-202975