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"The pro forma deposits as if the business combination or combinations had been completed at the beginning of the period. "

No definition available.

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"The pro forma net loans as if the business combination or combinations had been completed at the beginning of the period. "

No definition available.

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The consideration per share of acquiree based on entity's stock price in business combination.

No definition available.

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Represents the conversion ratio of number of shares exchanged in business combination.

No definition available.

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Represents fixed exchange ratio of entity's common stock in a business combination.

No definition available.

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Number of shares exchanged in business combination.

No definition available.

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Amount of proposed transaction value in business combination.

No definition available.

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The amount of cash outflow associated with the acquisition to be made at time of closing.

No definition available.

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The amount of cash outflow per share associated with the acquisition to be made at time of closing.

No definition available.

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Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(12))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
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-URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6578-128477

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
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-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522

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-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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Price of a single share of a number of saleable stocks of a company.

No definition available.

Name:	us-gaap_SharePrice
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Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

No definition available.

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Name:	dei_LegalEntityAxis=htbk_UnitedAmericanBankMember
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Name:	us-gaap_BusinessAcquisitionAxis=htbk_TriValleyBankAndUnitedAmericanBankMember
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