Addition period for transition period besides the period to delay the estimated impact of the adoption of the CECL Standard to regulatory capital as the company elected the option.

No definition available.

Name:	htbk_AdditionPeriodForTransitionBesidesPeriodToDelayEstimatedImpactOfAdoptionOfCeclStandardToRegulatoryCapitalAsCompanyElectedOption
Namespace Prefix:	htbk_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

Capital Requirements - General Information (Details)		12 Months Ended
Capital Requirements - General Information (Details)	Mar. 27, 2020	Dec. 31, 2020	Dec. 31, 2019
Capital Requirements
Period to delay the estimated impact of the adoption of the CECL Standard to regulatory capital as the company elected the option	2 years
Addition period for transition	3 years
HBC (Wholly-owned Subsidiary)
Capital Requirements
Capital conservation buffer (as a percent)		2.50%	2.50%