Name:	htbk_AvailableForSaleSecuritiesAndHeldToMaturitySecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositions
Namespace Prefix:	htbk_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

Represents the holdings of securities as percentage of shareholders' equity, considered as threshold for disclosure purpose.

No definition available.

Name:	htbk_AvailableForSaleSecuritiesAsPercentageOfShareholdersEquityConsideredAsThresholdForDisclosurePurpose
Namespace Prefix:	htbk_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

Represents the number of investment positions in the available-for-sale investments as of the balance sheet date.

No definition available.

Name:	htbk_AvailableForSaleSecuritiesQualitativeDisclosureNumberOfPositions
Namespace Prefix:	htbk_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

Represents the number of investment positions in the held to maturity investments as of the balance sheet date.

No definition available.

Name:	htbk_HeldToMaturitySecuritiesQualitativeDisclosureNumberOfPositions
Namespace Prefix:	htbk_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

Represents the number of holdings of securities of any one issuer other than the U.S. Government and its sponsored entities, in the amount greater than 10% of shareholders' equity.

No definition available.

Name:	htbk_InvestmentSecuritiesQualitativeDisclosureNumberOfHoldingsOfSecuritiesOfAnyOneIssuerOtherThanUsGovernmentAndSponsoredEntities
Namespace Prefix:	htbk_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

Represents the number of investment positions as of the balance sheet date.

No definition available.

Name:	htbk_InvestmentSecuritiesQualitativeDisclosureNumberOfPositions
Namespace Prefix:	htbk_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- References

No definition available.