Loans - Additional Information (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Focus Business Bank
Loans
Loans acquired in the Focus transaction	$ 102,921	$ 141,343

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