Age of appraisals that will considered as stale.

No definition available.

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- Definition

Period that a loan classified as Doubtful will remain outstanding.

+ References

No definition available.

+ Details

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- Definition

The frequencies of which external appraisals are updated.

+ References

No definition available.

+ Details

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- Definition

The maximum loan to value percentage.

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

The number of days that a loan receivable must be late to be considered past due.

+ References

No definition available.

+ Details

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- Definition

Percentage of the allowance for loan and lease losses as a percentage of total gross loans.

+ References

No definition available.

+ Details

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- Definition

The percentage of collateral coverage to loan balance, to consider restructured loan to performing and accrual status.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

The percentage of the gross loan portfolio that is secured by real estate.

+ References

No definition available.

+ Details

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Namespace Prefix:	boch_
Data Type:	num:percentItemType
Balance Type:	na
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- Definition

The percentage of unallocated allowance amount out of allowance for loan and lease losses.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of the reserve for unfunded commitments.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Percentage of gross portfolio loans that are classified as loans modified under a troubled debt restructuring.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

The fair value of financial assets, which are not recognized in the financial statements (off-balance sheet) because they fail to meet some other criterion for recognition.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13433-108611

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953676-111524

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Balance Type:	na
Period Type:	duration

- Definition

The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
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-Publisher FASB
-Name Accounting Standards Codification
-Glossary Recorded Investment
-URI http://asc.fasb.org/extlink&oid=65880944

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
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-Subparagraph (g)
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-Section 50
-Paragraph 2
-Subparagraph (b)(1)(ii)
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Balance Type:	credit
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- Definition

Reflects the unfunded portion of contractual agreements to lend funds to borrowers for loans whose terms have been modified by troubled debt restructuring.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=25495931&loc=d3e18794-111554

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Balance Type:	debit
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- Definition

Reflects the amount of additional interest income that would have been recorded if impaired or nonperforming loans were instead current, in compliance with their original terms, and outstanding throughout the reporting period or since origination (if held for part of the period).

+ References

+ Details

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Amount of deferred fees paid by borrowers and unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of loans that are being amortized into income as an adjustment to yield. Excludes amounts for loans and leases covered under loss sharing agreements.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6378536&loc=d3e10092-111533

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Note 5 - Loans (Details Textual)		3 Months Ended		6 Months Ended		12 Months Ended
Note 5 - Loans (Details Textual)	Jun. 30, 2016 USD ($)	Jun. 30, 2016 USD ($)	Jun. 30, 2015 USD ($)	Jun. 30, 2016 USD ($)	Jun. 30, 2015 USD ($)	Dec. 31, 2015 USD ($)
Loans 30 Days Past Due [Member]
Number of Days for Loan Past Due				30 days
Loans 60 Days Past Due [Member]
Number of Days for Loan Past Due				60 days
Loans 90 Days Past Due [Member]
Number of Days for Loan Past Due				90 days
Troubled Debt Restructuring [Member]
Financing Receivable, Modifications, Number of Contracts	108
Minimum [Member]
Frequency of External Appraisals Updating				180 days
Maximum [Member]
Frequency of External Appraisals Updating				1 year
Performing Financial Instruments [Member]
Impaired Financing Receivable, Recorded Investment	$ 7,500,000	$ 7,500,000		$ 7,500,000		$ 6,900,000
Unamortized Loan Commitment and Origination Fees and Unamortized Discounts or Premiums	2,800,000	2,800,000		2,800,000		2,300,000
Loans and Leases Receivable, Impaired, Commitment to Lend	0	0		$ 0		0
Age of Appraisals That Will Considered as Stale				1 year
Loans and Leases Receivable, Impaired, Interest Lost on Nonaccrual Loans		165,000	$ 95,000	$ 175,000	$ 209,000
Impaired Financing Receivable, Recorded Investment	18,921,000	18,921,000		$ 18,921,000		21,390,000
Percentage of Collateral Coverage to Loan Balance to Consider Restructured Loan to Performing and Accrual Status				100.00%
Financing Receivable, Modifications, Recorded Investment	$ 11,200,000	$ 11,200,000		$ 11,200,000		$ 15,900,000
Financing Receivable, Modifications, Number of Contracts	118	1	3	1	7
Troubled Debt Restructurings Percentage of Gross Portfolio Loans	1.49%	1.49%		1.49%		2.22%
Doubtful Grade Remaining Outstanding Period, Minimum				180 days
Loans and Leases Receivable, Allowance	$ 11,864,000	$ 11,864,000		$ 11,864,000		$ 11,180,000
Percentage of Allowance for Loan and Lease Losses out of Net Loans	1.57%	1.57%		1.57%		1.56%
Fair Value Disclosure, Off-balance Sheet Risks, Amount, Asset	$ 202,400,000	$ 202,400,000		$ 202,400,000		$ 230,600,000
Reserve for Unfunded Commitments Included in Other Liabilities	$ 695,000	$ 695,000		$ 695,000
Percentage of Loan Portfolio Secured by Real Estate	73.00%	73.00%		73.00%
Percentage of Unallocated Allowance Amount out of Allowance for Loan and Lease Losses				5.00%		5.00%
Maximum Loan to Value, Percentage				80.00%