cm:Level2TextBlock: us-gaap:LoansAndLeasesReceivableAllowanceForLoanLossesPolicy
| Loans and Leases Receivable, Allowance for Loan Losses Policy [Policy Text Block] |
| us-gaap:LoansAndLeasesReceivableAllowanceForLoanLossesPolicy |
| Disclosure of accounting policy for estimating the allowance for losses on loans and lease receivables. The disclosure may include (a) how the entity determines each element of the allowance, (b) which loans are evaluated individually and which loans are evaluated as a group, (c) how the entity determines both the allocated and unallocated portions of the allowance, (d) how the entity determines the loss factors applied to graded loans in order to develop a general allowance, and (e) what self-correcting mechanism the entity uses to reduce differences between estimated and actual losses. |
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| Text Block (HTML) (nonnum:textBlockItemType) |
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| us-gaap:LoansAndLeasesReceivableAllowanceForLoanLossesPolicy |