(26,276)

(19,461)

(26,276)

(5,136)

(5,205)

Note 5 - Net Investment In Leases: (Details) - Installments Due on Minimum Lease Payments Receivable, and the Expected Maturity of the Company's Estimated Residual Value: [Line Items]

(3,164)

14,087

17,270

342,589

Lease Receivable [Member]

136,993

106,908

59,268

25,813

11,323

17,637

357,942

(24,229)

Note 5 - Net Investment In Leases: (Details) - Installments Due on Minimum Lease Payments Receivable, and the Expected Maturity of the Company's Estimated Residual Value: [Line Items]

(2,916)

330,797

Estimated Residual Value [Member]

4,732

1,737

3,098

3,663

857

14,087

(2,047)

(248)

$ 11,792

Total estimated residual value of leased assets under a lease agreement.

No definition available.

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Estimated residual value of leased assets under a lease agreement which matures within one year of the balance sheet date.

No definition available.

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Estimated residual value of leased assets under a lease agreement which matures within the fifth year from the balance sheet date.

No definition available.

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Estimated residual value of leased assets under a lease agreement which matures within the fourth year from the balance sheet date.

No definition available.

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Estimated residual value of leased assets under a lease agreement which matures within the third year after the balance sheet date.

No definition available.

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Estimated residual value of leased assets under a lease agreement which matures within the second year from the balance sheet date.

No definition available.

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Data Type:	xbrli:monetaryItemType
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No authoritative reference available.

No definition available.

Name:	cfnb_EstimatedResidualValueOnLeasesReceivable
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Balance Type:	debit
Period Type:	instant

- Details

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No authoritative reference available.

No definition available.

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No authoritative reference available.

No definition available.

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Total lease receivable plus the estimated residual value of leased assets.

No definition available.

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Total lease receivable plus the estimated residual value of leased assets maturing after five years.

No definition available.

Name:	cfnb_TotalLeaseReceivablePlusEstimatedResidualValueMaturingAfterFiveYears.
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Total lease receivable plus the estimated residual value of leased assets maturing in five years.

No definition available.

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Total lease receivable plus the estimated residual value of leased assets maturing in four years.

No definition available.

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Data Type:	xbrli:monetaryItemType
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Total lease receivable plus the estimated residual value of leased assets maturing in three years.

No definition available.

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Total lease receivable plus the estimated residual value of leased assets maturing in two years.

No definition available.

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Total lease receivable plus the estimated residual value of leased assets maturing within one year.

No definition available.

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Unearned income associated with the estimated residual value of leased assets.

No definition available.

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No authoritative reference available.

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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This element represents revenue received, but not recognized for financial reporting purposes. Such deferred revenue may consist of and include amounts paid in advance by lessees and is net of the accumulated amortization of such amounts that to date have been recognized in revenue.

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

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-Topic 944

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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.

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Amount of deferred interest and fee income, unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of acquired loans. Excludes amounts for loans and leases covered under loss sharing agreements.

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The net amount due as of the balance sheet date consisting of: (a) minimum lease payments due on direct financing and sales-type leases, (b) unguaranteed residual value, and (c) any unamortized initial direct costs on direct financing leases; less: (i) executory costs, (ii) unearned income, and (iii) the accumulated allowance for uncollectible minimum lease payments.

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Future minimum rental payments in aggregate as of the balance sheet date under operating leases.

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Future rental payments receivable within one year of the balance sheet date under an operating lease.

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Future rental payments receivable within the fifth year from the balance sheet date under an operating lease.

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Future rental payments receivable within the fourth year from the balance sheet date under an operating lease.

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Future rental payments receivable within the third year from the balance sheet date under an operating lease.

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Future rental payments receivable within the second year from the balance sheet date under an operating lease.

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Future minimum lease payments receivable under operating leases for periods greater than five years following the balance sheet date.