Age of appraisals that will considered as stale.

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- Definition

Doubtful grade remaining outstanding period minimum.

+ 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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- Details

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- Definition

The number of days for loan past due.

+ References

No definition available.

+ Details

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- Definition

The allowance for loan and lease losses out of net loans as a percentage.

+ 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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Period Type:	duration

- Definition

The percentage of loan portfolio secured by real estate.

+ References

No definition available.

+ Details

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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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- Definition

The reserve for unfunded commitments included in other liabilities.

+ References

No definition available.

+ Details

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

- Definition

Troubled debt restructurings percentage of gross portfolio loans.

+ References

No definition available.

+ Details

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- Definition

Amount, after recoveries, of loans and leases that have been written-off.

+ References

No definition available.

+ Details

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Balance Type:	debit
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- 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=35750535&loc=d3e13433-108611

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- 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

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- 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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- Definition

Number of financing receivables that have been modified by troubled debt restructurings within the previous 12 months and for which there was a payment default.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 34

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Balance Type:	na
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- 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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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 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.7(d))

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Subparagraph d

-Article 9

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

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-Paragraph 11B

-Subparagraph (g)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-Subparagraph (c)(1)

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-Name Accounting Standards Codification

-Topic 310

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (b)(1)(ii)

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 6

-Section L

-Subsection 1

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- Definition

Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 45

-Paragraph 2

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Balance Type:	debit
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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

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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

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Balance Type:	credit
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- Definition

The cash inflow from loans reinstated and recovered that were previously deemed uncollectible.

+ References

No definition available.

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- Definition

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.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 20

-Section 45

-Paragraph 1

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Note 6 - Loans (Details) (USD $)	3 Months Ended		12 Months Ended
Note 6 - Loans (Details) (USD $)	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Note 6 - Loans (Details) [Line Items]
Unamortized Loan Commitment and Origination Fees and Unamortized Discounts or Premiums	$ 1,800,000		$ 998,000
Age of Appraisals That Will Considered As Stale	1 year
Loans and Leases Receivable, Impaired, Interest Lost on Nonaccrual Loans	163,000	188,000
Impaired Financing Receivable, Recorded Investment	27,735,000		31,408,000
Percentage of Collateral Coverage to Loan Balance to Consider Restructured Loan to Performing and Accrual Status	100.00%
Loans and Leases Receivable, Impaired, Commitment to Lend	0		0
Financing Receivable, Modifications, Recorded Investment	21,400,000		23,500,000
Financing Receivable, Modifications, Number of Contracts	4	1
Troubled Debt Restructurings Percentage of Gross Portfolio Loans	3.06%		3.55%
Financing Receivable, Modifications, Subsequent Default, Number of Contracts	1	0
Doubtful Grade Remaining Outstanding Period Minimum	6 months
Loans and Leases Receivable, Gross	699,229,000		660,898,000
Loans and Leases Receivable, Allowance	11,296,000		10,820,000
Percentage of Allowance for Loan and Lease Losses Out of Net Loans	1.62%		1.64%
Fair Value Disclosure, Off-balance Sheet Risks, Amount, Asset	199,000,000
Reserve for Unfunded Commitments Included in Other Liabilities	695,000		695,000
Proceeds from Recoveries of Loans Previously Charged off	476,000
Allowance for Loan and Lease Losses Write-offs, Net			6,500,000
Percentage of Loan Portfolio Secured by Real Estate	72.00%
Percentage of Unallocated Allowance Amount Out of Allowance for Loan and Lease Losses	4.00%		3.00%
Maximum Loan To Value Percentage	80.00%boch_MaximumLoanToValuePercentage
Loans 30 Days Past Due [Member]
Note 6 - Loans (Details) [Line Items]
Number of Days for Loan Past Due	30 days
Loans 60 Days Past Due [Member]
Note 6 - Loans (Details) [Line Items]
Number of Days for Loan Past Due	60 days
Loans 90 Days Past Due [Member]
Note 6 - Loans (Details) [Line Items]
Number of Days for Loan Past Due	90 days
Performing Loans [Member]
Note 6 - Loans (Details) [Line Items]
Impaired Financing Receivable, Recorded Investment	8,700,000		9,200,000
Financing Receivable, Modifications, Number of Contracts	99
Troubled Debt Restructuring [Member]
Note 6 - Loans (Details) [Line Items]
Financing Receivable, Modifications, Number of Contracts	121
Scenario, Adjustment [Member] \| Pass [Member]
Note 6 - Loans (Details) [Line Items]
Loans and Leases Receivable, Gross			46,900,000
Pass [Member]
Note 6 - Loans (Details) [Line Items]
Loans and Leases Receivable, Gross	$ 638,215,000		$ 594,575,000
Minimum [Member]
Note 6 - Loans (Details) [Line Items]
Frequency of External Appraisals Updating	6 months
Maximum [Member]
Note 6 - Loans (Details) [Line Items]
Frequency of External Appraisals Updating	12 months