XML 40 R28.htm IDEA: XBRL DOCUMENT
v3.19.1

LOANS (Tables) | 3 Months Ended
--- | ---
Mar. 31, 2019
Loans and Leases Receivable Disclosure [Line Items] |
Loans Receivable, Net | The balances of these classes are summarized as follows:
(000's omitted) |  | March 31, 2019 |  |  | December 31, 2018 |
Business lending |  | $ | 2,410,477 |  |  | $ | 2,396,977 |
Consumer mortgage |  |  | 2,237,430 |  |  |  | 2,235,408 |
Consumer indirect |  |  | 1,070,840 |  |  |  | 1,083,207 |
Consumer direct |  |  | 173,042 |  |  |  | 178,820 |
Home equity |  |  | 374,297 |  |  |  | 386,709 |
Gross loans, including deferred origination costs |  |  | 6,266,086 |  |  |  | 6,281,121 |
Allowance for loan losses |  |  | (49,107 | ) |  |  | (49,284 | )
Loans, net of allowance for loan losses |  | $ | 6,216,979 |  |  | $ | 6,231,837 |
Accretable Discount Related to Credit Impaired Acquired Loans | The changes in the accretable discount related to the credit impaired acquired loans are as follows:
(000’s omitted) |  |  |
Balance at December 31, 2018 |  | $ | 437 |
Accretion recognized, year-to-date |  |  | (74 | )
Balance at March 31, 2019 |  | $ | 363 |
Aged Analysis of Past Due Loans by Class | The following is an aged analysis of the Company’s past due loans, by class as of March 31, 2019: Legacy Loans (excludes loans acquired after January 1, 2009)
(000’s omitted) |  | Past Due 30 – 89 Days |  |  | 90+ Days Past Due and Still Accruing |  |  | Nonaccrual |  |  | Total Past Due |  |  | Current |  |  | Total Loans |
Business lending |  | $ | 6,042 |  |  | $ | 68 |  |  | $ | 4,147 |  |  | $ | 10,257 |  |  | $ | 1,652,950 |  |  | $ | 1,663,207 |
Consumer mortgage |  |  | 8,937 |  |  |  | 1,960 |  |  |  | 9,794 |  |  |  | 20,691 |  |  |  | 1,843,754 |  |  |  | 1,864,445 |
Consumer indirect |  |  | 9,824 |  |  |  | 201 |  |  |  | 0 |  |  |  | 10,025 |  |  |  | 1,051,493 |  |  |  | 1,061,518 |
Consumer direct |  |  | 985 |  |  |  | 41 |  |  |  | 0 |  |  |  | 1,026 |  |  |  | 169,334 |  |  |  | 170,360 |
Home equity |  |  | 1,005 |  |  |  | 323 |  |  |  | 1,583 |  |  |  | 2,911 |  |  |  | 301,113 |  |  |  | 304,024 |
Total |  | $ | 26,793 |  |  | $ | 2,593 |  |  | $ | 15,524 |  |  | $ | 44,910 |  |  | $ | 5,018,644 |  |  | $ | 5,063,554 |
Acquired Loans (includes loans acquired after January 1, 2009)
(000’s omitted) |  | Past Due 30 – 89 Days |  |  | 90+ Days Past Due and Still Accruing |  |  | Nonaccrual |  |  | Total Past Due |  |  | Acquired Impaired(1) |  |  | Current |  |  | Total Loans |
Business lending |  | $ | 2,526 |  |  | $ | 66 |  |  | $ | 3,254 |  |  | $ | 5,846 |  |  | $ | 5,342 |  |  | $ | 736,082 |  |  | $ | 747,270 |
Consumer mortgage |  |  | 883 |  |  |  | 287 |  |  |  | 1,954 |  |  |  | 3,124 |  |  |  | 0 |  |  |  | 369,861 |  |  |  | 372,985 |
Consumer indirect |  |  | 32 |  |  |  | 33 |  |  |  | 0 |  |  |  | 65 |  |  |  | 0 |  |  |  | 9,257 |  |  |  | 9,322 |
Consumer direct |  |  | 33 |  |  |  | 25 |  |  |  | 0 |  |  |  | 58 |  |  |  | 0 |  |  |  | 2,624 |  |  |  | 2,682 |
Home equity |  |  | 558 |  |  |  | 15 |  |  |  | 520 |  |  |  | 1,093 |  |  |  | 0 |  |  |  | 69,180 |  |  |  | 70,273 |
Total |  | $ | 4,032 |  |  | $ | 426 |  |  | $ | 5,728 |  |  | $ | 10,186 |  |  | $ | 5,342 |  |  | $ | 1,187,004 |  |  | $ | 1,202,532 |
(1) | Acquired impaired loans were not classified as nonperforming assets as the loans are considered to be performing under ASC 310-30. As a result interest income, through the accretion of the difference between the carrying amount of the loans and the expected cashflows, is being recognized on all acquired impaired loans.
The following is an aged analysis of the Company’s past due loans by class as of December 31, 2018: Legacy Loans (excludes loans acquired after January 1, 2009)
(000’s omitted) |  | Past Due 30 – 89 Days |  |  | 90+ Days Past Due and Still Accruing |  |  | Nonaccrual |  |  | Total Past Due |  |  | Current |  |  | Total Loans |
Business lending |  | $ | 5,261 |  |  | $ | 179 |  |  | $ | 4,872 |  |  | $ | 10,312 |  |  | $ | 1,608,515 |  |  | $ | 1,618,827 |
Consumer mortgage |  |  | 12,468 |  |  |  | 1,393 |  |  |  | 9,872 |  |  |  | 23,733 |  |  |  | 1,824,717 |  |  |  | 1,848,450 |
Consumer indirect |  |  | 14,609 |  |  |  | 258 |  |  |  | 0 |  |  |  | 14,867 |  |  |  | 1,057,525 |  |  |  | 1,072,392 |
Consumer direct |  |  | 1,778 |  |  |  | 48 |  |  |  | 0 |  |  |  | 1,826 |  |  |  | 173,948 |  |  |  | 175,774 |
Home equity |  |  | 983 |  |  |  | 228 |  |  |  | 1,438 |  |  |  | 2,649 |  |  |  | 309,892 |  |  |  | 312,541 |
Total |  | $ | 35,099 |  |  | $ | 2,106 |  |  | $ | 16,182 |  |  | $ | 53,387 |  |  | $ | 4,974,597 |  |  | $ | 5,027,984 |
Acquired Loans (includes loans acquired after January 1, 2009)
(000’s omitted) |  | Past Due 30 – 89 Days |  |  | 90+ Days Past Due and Still Accruing |  |  | Nonaccrual |  |  | Total Past Due |  |  | Acquired Impaired(1) |  |  | Current |  |  | Total Loans |
Business lending |  | $ | 974 |  |  | $ | 0 |  |  | $ | 3,498 |  |  | $ | 4,472 |  |  | $ | 5,446 |  |  | $ | 768,232 |  |  | $ | 778,150 |
Consumer mortgage |  |  | 841 |  |  |  | 232 |  |  |  | 2,390 |  |  |  | 3,463 |  |  |  | 0 |  |  |  | 383,495 |  |  |  | 386,958 |
Consumer indirect |  |  | 78 |  |  |  | 34 |  |  |  | 0 |  |  |  | 112 |  |  |  | 0 |  |  |  | 10,703 |  |  |  | 10,815 |
Consumer direct |  |  | 115 |  |  |  | 4 |  |  |  | 0 |  |  |  | 119 |  |  |  | 0 |  |  |  | 2,927 |  |  |  | 3,046 |
Home equity |  |  | 613 |  |  |  | 79 |  |  |  | 474 |  |  |  | 1,166 |  |  |  | 0 |  |  |  | 73,002 |  |  |  | 74,168 |
Total |  | $ | 2,621 |  |  | $ | 349 |  |  | $ | 6,362 |  |  | $ | 9,332 |  |  | $ | 5,446 |  |  | $ | 1,238,359 |  |  | $ | 1,253,137 |
(1) | Acquired impaired loans were not classified as nonperforming assets as the loans are considered to be performing under ASC 310-30. As a result interest income, through the accretion of the difference between the carrying amount of the loans and the expected cashflows, is being recognized on all acquired impaired loans.
Non-Business Impaired Loans | A summary of individually evaluated impaired loans as of March 31, 2019 and December 31, 2018 follows:
(000’s omitted) |  | March 31, 2019 |  |  | December 31, 2018 |
Loans with allowance allocation |  | $ | 0 |  |  | $ | 3,956 |
Loans without allowance allocation |  |  | 5,118 |  |  |  | 2,230 |
Carrying balance |  |  | 5,118 |  |  |  | 6,186 |
Contractual balance |  |  | 12,052 |  |  |  | 12,078 |
Specifically allocated allowance |  |  | 0 |  |  |  | 956 |
Troubled Debt Restructurings on Financing Receivables | Information regarding TDRs as of March 31, 2019 and December 31, 2018 is as follows:
|  | March 31, 2019 |  |  | December 31, 2018 |
(000’s omitted) |  | Nonaccrual |  |  | Accruing |  |  | Total |  |  | Nonaccrual |  |  | Accruing |  |  | Total |
|  |  | # |  |  | Amount |  |  |  | # |  |  | Amount |  |  |  | # |  |  | Amount |  |  |  | # |  |  | Amount |  |  |  | # |  |  | Amount |  |  |  | # |  |  | Amount |
Business lending |  |  | 3 |  |  | $ | 87 |  |  |  | 2 |  |  | $ | 161 |  |  |  | 5 |  |  | $ | 248 |  |  |  | 4 |  |  | $ | 162 |  |  |  | 2 |  |  | $ | 165 |  |  |  | 6 |  |  | $ | 327 |
Consumer mortgage |  |  | 50 |  |  |  | 2,214 |  |  |  | 50 |  |  |  | 2,027 |  |  |  | 100 |  |  |  | 4,241 |  |  |  | 46 |  |  |  | 1,986 |  |  |  | 46 |  |  |  | 1,769 |  |  |  | 92 |  |  |  | 3,755 |
Consumer indirect |  |  | 0 |  |  |  | 0 |  |  |  | 85 |  |  |  | 916 |  |  |  | 85 |  |  |  | 916 |  |  |  | 0 |  |  |  | 0 |  |  |  | 77 |  |  |  | 857 |  |  |  | 77 |  |  |  | 857 |
Consumer direct |  |  | 0 |  |  |  | 0 |  |  |  | 15 |  |  |  | 1 |  |  |  | 15 |  |  |  | 1 |  |  |  | 0 |  |  |  | 0 |  |  |  | 22 |  |  |  | 71 |  |  |  | 22 |  |  |  | 71 |
Home equity |  |  | 13 |  |  |  | 233 |  |  |  | 9 |  |  |  | 270 |  |  |  | 22 |  |  |  | 503 |  |  |  | 12 |  |  |  | 240 |  |  |  | 9 |  |  |  | 275 |  |  |  | 21 |  |  |  | 515 |
Total |  |  | 66 |  |  | $ | 2,534 |  |  |  | 161 |  |  | $ | 3,375 |  |  |  | 227 |  |  | $ | 5,909 |  |  |  | 62 |  |  | $ | 2,388 |  |  |  | 156 |  |  | $ | 3,137 |  |  |  | 218 |  |  | $ | 5,525 |
The following table presents information related to loans modified in a TDR during the three months ended March 31, 2019 and 2018. Of the loans noted in the table below, all loans for the three months ended March 31, 2019 and 2018 were modified due to a Chapter 7 bankruptcy as described previously. The financial effects of these restructurings were immaterial
|  | Three Months Ended March 31, 2019 |  |  | Three Months Ended March 31, 2018 |
(000’s omitted) |  | Number of loans modified |  |  | Outstanding Balance |  |  | Number of loans modified |  |  | Outstanding Balance |
Business lending |  |  | 0 |  |  | $ | 0 |  |  |  | 1 |  |  | $ | 93 |
Consumer mortgage |  |  | 8 |  |  |  | 665 |  |  |  | 0 |  |  |  | 0 |
Consumer indirect |  |  | 11 |  |  |  | 98 |  |  |  | 4 |  |  |  | 41 |
Consumer direct |  |  | 0 |  |  |  | 0 |  |  |  | 2 |  |  |  | 2 |
Home equity |  |  | 1 |  |  |  | 4 |  |  |  | 0 |  |  |  | 0 |
Total |  |  | 20 |  |  | $ | 767 |  |  |  | 7 |  |  | $ | 136 |
Allowance for Loan Losses by Class | The following presents by class the activity in the allowance for loan losses:
|  | Three Months Ended March 31, 2019 |
(000’s omitted) |  | Business Lending |  |  | Consumer Mortgage |  |  | Consumer Indirect |  |  | Consumer Direct |  |  | Home Equity |  |  | Unallocated |  |  | Acquired Impaired |  |  | Total |
Beginning balance |  | $ | 18,522 |  |  | $ | 10,124 |  |  | $ | 14,366 |  |  | $ | 3,095 |  |  | $ | 2,144 |  |  | $ | 1,000 |  |  | $ | 33 |  |  | $ | 49,284 |
Charge-offs |  |  | (1,216 | ) |  |  | (253 | ) |  |  | (1,823 | ) |  |  | (535 | ) |  |  | (74 | ) |  |  | 0 |  |  |  | 0 |  |  |  | (3,901 | )
Recoveries |  |  | 134 |  |  |  | 22 |  |  |  | 962 |  |  |  | 179 |  |  |  | 5 |  |  |  | 0 |  |  |  | 0 |  |  |  | 1,302 |
Provision |  |  | 831 |  |  |  | 424 |  |  |  | 746 |  |  |  | 317 |  |  |  | (8 | ) |  |  | (10 | ) |  |  | 122 |  |  |  | 2,422 |
Ending balance |  | $ | 18,271 |  |  | $ | 10,317 |  |  | $ | 14,251 |  |  | $ | 3,056 |  |  | $ | 2,067 |  |  | $ | 990 |  |  | $ | 155 |  |  | $ | 49,107 |
|  | Three Months Ended March 31, 2018 |
(000’s omitted) |  | Business Lending |  |  | Consumer Mortgage |  |  | Consumer Indirect |  |  | Consumer Direct |  |  | Home Equity |  |  | Unallocated |  |  | Acquired Impaired |  |  | Total |
Beginning balance |  | $ | 17,257 |  |  | $ | 10,465 |  |  | $ | 13,468 |  |  | $ | 3,039 |  |  | $ | 2,107 |  |  | $ | 1,100 |  |  | $ | 147 |  |  | $ | 47,583 |
Charge-offs |  |  | (1,669 | ) |  |  | (199 | ) |  |  | (2,284 | ) |  |  | (496 | ) |  |  | (56 | ) |  |  | 0 |  |  |  | (43 | ) |  |  | (4,747 | )
Recoveries |  |  | 198 |  |  |  | 8 |  |  |  | 1,151 |  |  |  | 222 |  |  |  | 9 |  |  |  | 0 |  |  |  | 0 |  |  |  | 1,588 |
Provision |  |  | 1,821 |  |  |  | 108 |  |  |  | 1,363 |  |  |  | 219 |  |  |  | (20 | ) |  |  | (16 | ) |  |  | 204 |  |  |  | 3,679 |
Ending balance |  | $ | 17,607 |  |  | $ | 10,382 |  |  | $ | 13,698 |  |  | $ | 2,984 |  |  | $ | 2,040 |  |  | $ | 1,084 |  |  | $ | 308 |  |  | $ | 48,103 |
Business Lending [Member] |
Loans and Leases Receivable Disclosure [Line Items] |
Loans by Credit Quality Indicator | The following table shows the amount of business lending loans by credit quality category:
|  | March 31, 2019 |  |  | December 31, 2018 |
(000’s omitted) |  | Legacy |  |  | Acquired |  |  | Total |  |  | Legacy |  |  | Acquired |  |  | Total |
Pass |  | $ | 1,475,145 |  |  | $ | 659,645 |  |  | $ | 2,134,790 |  |  | $ | 1,439,337 |  |  | $ | 702,493 |  |  | $ | 2,141,830 |
Special mention |  |  | 108,129 |  |  |  | 53,562 |  |  |  | 161,691 |  |  |  | 105,065 |  |  |  | 40,107 |  |  |  | 145,172 |
Classified |  |  | 79,933 |  |  |  | 28,721 |  |  |  | 108,654 |  |  |  | 74,425 |  |  |  | 28,525 |  |  |  | 102,950 |
Doubtful |  |  | 0 |  |  |  | 0 |  |  |  | 0 |  |  |  | 0 |  |  |  | 1,579 |  |  |  | 1,579 |
Acquired impaired |  |  | 0 |  |  |  | 5,342 |  |  |  | 5,342 |  |  |  | 0 |  |  |  | 5,446 |  |  |  | 5,446 |
Total |  | $ | 1,663,207 |  |  | $ | 747,270 |  |  | $ | 2,410,477 |  |  | $ | 1,618,827 |  |  | $ | 778,150 |  |  | $ | 2,396,977 |
All Other Loans [Member] |
Loans and Leases Receivable Disclosure [Line Items] |
Loans by Credit Quality Indicator | The following table details the balances in all other loan categories at March 31, 2019: Legacy Loans (excludes loans acquired after January 1, 2009)
(000’s omitted) |  | Consumer Mortgage |  |  | Consumer Indirect |  |  | Consumer Direct |  |  | Home Equity |  |  | Total |
Performing |  | $ | 1,852,691 |  |  | $ | 1,061,317 |  |  | $ | 170,319 |  |  | $ | 302,118 |  |  | $ | 3,386,445 |
Nonperforming |  |  | 11,754 |  |  |  | 201 |  |  |  | 41 |  |  |  | 1,906 |  |  |  | 13,902 |
Total |  | $ | 1,864,445 |  |  | $ | 1,061,518 |  |  | $ | 170,360 |  |  | $ | 304,024 |  |  | $ | 3,400,347 |
Acquired Loans (includes loans acquired after January 1, 2009)
(000’s omitted) |  | Consumer Mortgage |  |  | Consumer Indirect |  |  | Consumer Direct |  |  | Home Equity |  |  | Total |
Performing |  | $ | 370,744 |  |  | $ | 9,289 |  |  | $ | 2,657 |  |  | $ | 69,738 |  |  | $ | 452,428 |
Nonperforming |  |  | 2,241 |  |  |  | 33 |  |  |  | 25 |  |  |  | 535 |  |  |  | 2,834 |
Total |  | $ | 372,985 |  |  | $ | 9,322 |  |  | $ | 2,682 |  |  | $ | 70,273 |  |  | $ | 455,262 |
The following table details the balances in all other loan categories at December 31, 2018: Legacy Loans (excludes loans acquired after January 1, 2009)
(000’s omitted) |  | Consumer Mortgage |  |  | Consumer Indirect |  |  | Consumer Direct |  |  | Home Equity |  |  | Total |
Performing |  | $ | 1,837,185 |  |  | $ | 1,072,134 |  |  | $ | 175,726 |  |  | $ | 310,875 |  |  | $ | 3,395,920 |
Nonperforming |  |  | 11,265 |  |  |  | 258 |  |  |  | 48 |  |  |  | 1,666 |  |  |  | 13,237 |
Total |  | $ | 1,848,450 |  |  | $ | 1,072,392 |  |  | $ | 175,774 |  |  | $ | 312,541 |  |  | $ | 3,409,157 |
Acquired Loans (includes loans acquired after January 1, 2009)
(000’s omitted) |  | Consumer Mortgage |  |  | Consumer Indirect |  |  | Consumer Direct |  |  | Home Equity |  |  | Total |
Performing |  | $ | 384,336 |  |  | $ | 10,781 |  |  | $ | 3,042 |  |  | $ | 73,615 |  |  | $ | 471,774 |
Nonperforming |  |  | 2,622 |  |  |  | 34 |  |  |  | 4 |  |  |  | 553 |  |  |  | 3,213 |
Total |  | $ | 386,958 |  |  | $ | 10,815 |  |  | $ | 3,046 |  |  | $ | 74,168 |  |  | $ | 474,987 |

X
- Definition Tabular disclosure of changes to the aggregate cash flows related to loans expected to be collected over the investor's initial investment in the loan. This relates to loans with deteriorating of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable. + References No definition available. + Details
Name: | cbu_ScheduleOfAccretableDiscountRelatedToCreditImpairedAcquiredLoansTableTextBlock
Namespace Prefix: | cbu_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of financing receivables (examples of financing receivables include loans, trade accounts receivable and notes receivable) and activity in the allowance for credit losses account. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524 + Details
Name: | us-gaap_AllowanceForCreditLossesOnFinancingReceivablesTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of financing receivables by credit quality indicator. The credit quality indicator is a statistic about the credit quality of financing receivables. Examples include, but not limited to, consumer credit risk scores, credit-rating-agency ratings, an entity's internal credit risk grades, loan-to-value ratios, collateral, collection experience and other internal metrics. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 29 -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953659-111524 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 55 -Paragraph 19 -URI http://asc.fasb.org/extlink&oid=82894031&loc=SL6953803-111525 + Details
Name: | us-gaap_FinancingReceivableCreditQualityIndicatorsTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of impaired financing receivables. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524 + Details
Name: | us-gaap_ImpairedFinancingReceivablesTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_LoansAndLeasesReceivableDisclosureLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of financing receivables that are past due but not impaired, financing receivables that are 90 days past due and still accruing, and financing receivables on nonaccrual status. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 7A -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953401-111524 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5111-111524 + Details
Name: | us-gaap_PastDueFinancingReceivablesTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of the various types of trade accounts and notes receivable and for each the gross carrying value, allowance, and net carrying value as of the balance sheet date. Presentation is categorized by current, noncurrent and unclassified receivables. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.3,4) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of financing receivables and troubled debt restructurings. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953676-111524 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 34 -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953682-111524 + Details
Name: | us-gaap_TroubledDebtRestructuringsOnFinancingReceivablesTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_CommercialLoanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=cbu_AllOtherLoansMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |