The amount of brokered time deposits are redeemed during the period.

No definition available.

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Namespace Prefix:	boch_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The number of branches acquired in an acquisition.

+ References

No definition available.

+ Details

Name:	boch_NumberOfBranchesAcquired
Namespace Prefix:	boch_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of offsite ATM Location acquired in an acquisition.

+ References

No definition available.

+ Details

Name:	boch_NumberOfOffsiteATMLocationAcquired
Namespace Prefix:	boch_
Data Type:	xbrli:integerItemType
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- Definition

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 23
-URI http://asc.fasb.org/extlink&oid=84229725&loc=d3e1043-128460

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of assets acquired at the acquisition date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=84161108&loc=d3e4845-128472

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of liabilities assumed at the acquisition date.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3213-108585

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The cash outflow for the payment of loan drawn from Federal Home Loan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3291-108585

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

Name:	us-gaap_FederalHomeLoanBankAdvancesBranchOfFHLBBankAxis=us-gaap_FederalHomeLoanBankOfSanFranciscoMember
Namespace Prefix:
Data Type:	na
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- Details

Name:	us-gaap_BusinessAcquisitionAxis=boch_BankOfAmericaBranchesMember
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Period Type:

Note 25 - Branch Acquisition (Details Textual) $ in Thousands			12 Months Ended
	Mar. 14, 2016 USD ($)	Mar. 11, 2016 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Business Combination, Acquisition Related Costs			$ 580	$ 347
Federal Home Loan Bank of San Francisco [Member]
Repayments of Federal Home Loan Bank Borrowings	$ 75,000
Bank of America Branches [Member]
Number of Branches Acquired		5
Number of Offsite ATM Location Acquired		3
Payments to Acquire Businesses, Gross		$ 6,656
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets		155,230
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities		$ 149,239
Brokered Time Deposits Redeemed	$ 17,500