XML 70 R57.htm IDEA: XBRL DOCUMENT
v3.20.4

Summary of Significant Accounting Policies - Cash and Cash Equivalents (Details) | 12 Months Ended
--- | ---
Dec. 31, 2020
Cash and Cash Equivalents |
Period for which federal funds are sold and purchased | 1 day

X
- Definition Represents the period for which federal funds are sold and purchased by the entity. + References No definition available. + Details
Name: | htbk_PeriodForWhichFederalFundsAreSoldAndPurchased
Namespace Prefix: | htbk_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_CashAndCashEquivalentsAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration