$CBU
Community Financial System Inc Stock $cbu

$cbu Overview Financials Valuation SEC Filings Company Website

2021 Q2 Form 10-Q Financial Statement

#000110465921102085 Filed on August 09, 2021

Income Statement

Concept	2021 Q2	2020 Q2	2020 Q1
Revenue	$95.36M	$97.19M	$97.00M
YoY Change	-1.88%		4.65%
Cost Of Revenue
YoY Change
Gross Profit
YoY Change
Gross Profit Margin
Selling, General & Admin
YoY Change
% of Gross Profit
Research & Development	$12.77M	$10.83M	$10.41M
YoY Change	17.84%		10.79%
% of Gross Profit
Depreciation & Amortization	$7.400M	$7.600M	$4.079M
YoY Change	-2.63%	-3.8%	-49.01%
% of Gross Profit
Operating Expenses	$12.77M	$10.83M	$10.41M
YoY Change	17.84%		10.79%
Operating Profit
YoY Change
Interest Expense	$3.255M	$5.241M	$6.941M
YoY Change	-37.89%		19.22%
% of Operating Profit
Other Income/Expense, Net
YoY Change
Pretax Income	$62.36M	$44.21M	$49.42M
YoY Change	41.05%	-21.65%	-4.01%
Income Tax	$14.42M	$8.964M	$9.285M
% Of Pretax Income	23.12%	20.28%	18.79%
Net Earnings	$47.94M	$35.25M	$40.13M
YoY Change	36.02%	-21.7%	-4.32%
Net Earnings / Revenue	50.28%	36.27%	41.38%
Basic Earnings Per Share	$0.89	$0.67	$0.77
Diluted Earnings Per Share	$0.88	$0.66	$0.76
COMMON SHARES
Basic Shares Outstanding	54.01M	52.49M	52.04M
Diluted Shares Outstanding	54.47M	52.83M	52.46M

Balance Sheet

Concept	2021 Q2	2020 Q2	2020 Q1
SHORT-TERM ASSETS
Cash & Short-Term Investments
YoY Change
Cash & Equivalents	$2.206B	$1.320B	$529.3M
Short-Term Investments
Other Short-Term Assets
YoY Change
Inventory
Prepaid Expenses
Receivables
Other Receivables
Total Short-Term Assets
YoY Change
LONG-TERM ASSETS
Property, Plant & Equipment	$161.0M	$167.0M	$163.0M
YoY Change	-3.59%	7.74%	7.24%
Goodwill	$5.669M	$792.7M	$773.5M
YoY Change	-99.28%	8.07%	5.45%
Intangibles	$47.78M	$60.05M	$59.45M
YoY Change	-20.43%	-10.4%	-16.17%
Long-Term Investments
YoY Change
Other Assets
YoY Change
Total Long-Term Assets
YoY Change
TOTAL ASSETS
Total Short-Term Assets
Total Long-Term Assets
Total Assets	$14.80B	$13.44B	$11.81B
YoY Change	10.09%	25.12%	8.18%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$200.0M	$246.0M	$227.0M
YoY Change	-18.7%	48.19%	47.4%
Accrued Expenses
YoY Change
Deferred Revenue
YoY Change
Short-Term Debt	$195.0M	$168.0M	$205.0M
YoY Change	16.07%	18.31%	-18.0%
Long-Term Debt Due
YoY Change
Total Short-Term Liabilities	$200.0M	$246.0M	$227.0M
YoY Change	-18.7%	20.59%	19.47%
LONG-TERM LIABILITIES
Long-Term Debt	$3.000M	$93.00M	$91.00M
YoY Change	-96.77%	-5.1%	-7.14%
Other Long-Term Liabilities		$1.000M	$1.000M
YoY Change		0.0%	0.0%
Total Long-Term Liabilities	$3.000M	$94.00M	$92.00M
YoY Change	-96.81%	-5.05%	-7.07%
TOTAL LIABILITIES
Total Short-Term Liabilities	$200.0M	$246.0M	$227.0M
Total Long-Term Liabilities	$3.000M	$94.00M	$92.00M
Total Liabilities	$12.74B	$11.36B	$9.832B
YoY Change	12.12%	27.16%	7.35%
SHAREHOLDERS EQUITY
Retained Earnings	$1.016B
YoY Change
Common Stock
YoY Change
Preferred Stock
YoY Change
Treasury Stock (at cost)	$5.632M
YoY Change
Treasury Stock Shares	$145.2K
Shareholders Equity	$2.061B	$2.082B	$1.977B
YoY Change
Total Liabilities & Shareholders Equity	$14.80B	$13.44B	$11.81B
YoY Change	10.1%	25.12%	8.18%

Cashflow Statement

Concept	2021 Q2	2020 Q2	2020 Q1
OPERATING ACTIVITIES
Net Income	$47.94M	$35.25M	$40.13M
YoY Change	36.02%	-21.7%	-4.32%
Depreciation, Depletion And Amortization	$7.400M	$7.600M	$4.079M
YoY Change	-2.63%	-3.8%	-49.01%
Cash From Operating Activities	$26.30M	$68.70M	$26.69M
YoY Change	-61.72%	24.23%	-22.85%
INVESTING ACTIVITIES
Capital Expenditures	-$4.800M	-$1.600M	$3.020M
YoY Change	200.0%	-42.86%	-351.67%
Acquisitions	$29.87M
YoY Change
Other Investing Activities	-$14.40M	-$249.6M	$52.40M
YoY Change	-94.23%	-143.87%	1.35%
Cash From Investing Activities	-$19.20M	-$251.2M	$49.42M
YoY Change	-92.36%	-144.36%	-1.95%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net			-$6.325M
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	47.60M	973.1M	248.2M
YoY Change	-95.11%	-481.46%	17.35%
NET CHANGE
Cash From Operating Activities	26.30M	68.70M	26.69M
Cash From Investing Activities	-19.20M	-251.2M	49.42M
Cash From Financing Activities	47.60M	973.1M	248.2M
Net Change In Cash	54.70M	790.6M	324.3M
YoY Change	-93.08%	115.72%	9.38%
FREE CASH FLOW
Cash From Operating Activities	$26.30M	$68.70M	$26.69M
Capital Expenditures	-$4.800M	-$1.600M	$3.020M
Free Cash Flow	$31.10M	$70.30M	$23.67M
YoY Change	-55.76%	21.0%	-33.87%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value
CY2021Q2	us-gaap	Commitments And Contingencies CommitmentsAndContingencies
CY2020Q4	us-gaap	Commitments And Contingencies CommitmentsAndContingencies
	dei	Entity Central Index Key EntityCentralIndexKey	0000723188
	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2021
	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	Q2
	dei	Entity Registrant Name EntityRegistrantName	COMMUNITY BANK SYSTEM, INC.
	dei	Amendment Flag AmendmentFlag	false
	dei	Document Type DocumentType	10-Q
	dei	Document Quarterly Report DocumentQuarterlyReport	true
	dei	Document Period End Date DocumentPeriodEndDate	2021-06-30
	dei	Document Transition Report DocumentTransitionReport	false
	dei	Entity File Number EntityFileNumber	001-13695
	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	DE
	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	16-1213679
	dei	Entity Address Address Line1 EntityAddressAddressLine1	5790 Widewaters Parkway
	dei	Entity Address City Or Town EntityAddressCityOrTown	DeWitt
	dei	Entity Address State Or Province EntityAddressStateOrProvince	NY
	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	13214
	dei	City Area Code CityAreaCode	315
	dei	Local Phone Number LocalPhoneNumber	445-2282
	dei	Security12b Title Security12bTitle	Common Stock, $1.00 par value per share
	dei	Trading Symbol TradingSymbol	CBU
	dei	Security Exchange Name SecurityExchangeName	NYSE
	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
	dei	Entity Interactive Data Current EntityInteractiveDataCurrent	Yes
	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
	dei	Entity Small Business EntitySmallBusiness	false
	dei	Entity Emerging Growth Company EntityEmergingGrowthCompany	false
	dei	Entity Shell Company EntityShellCompany	false
CY2021Q3	dei	Entity Common Stock Shares Outstanding EntityCommonStockSharesOutstanding	53918062
CY2021Q2	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	2205926000
CY2020Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	1645805000
CY2021Q2	us-gaap	Available For Sale Securities Amortized Cost AvailableForSaleSecuritiesAmortizedCost	4039978000
CY2020Q4	us-gaap	Available For Sale Securities Amortized Cost AvailableForSaleSecuritiesAmortizedCost	3427779000
CY2021Q2	us-gaap	Available For Sale Securities AvailableForSaleSecurities	4012739000
CY2020Q4	us-gaap	Available For Sale Securities AvailableForSaleSecurities	3547892000
CY2021Q2	cbu	Other Investments And Equity Securities At Cost OtherInvestmentsAndEquitySecuritiesAtCost	43955000
CY2020Q4	cbu	Other Investments And Equity Securities At Cost OtherInvestmentsAndEquitySecuritiesAtCost	46511000
CY2021Q2	cbu	Other Investment And Equity Securities Fair Value OtherInvestmentAndEquitySecuritiesFairValue	44923000
CY2020Q4	cbu	Other Investment And Equity Securities Fair Value OtherInvestmentAndEquitySecuritiesFairValue	47455000
CY2021Q2	us-gaap	Loans Receivable Held For Sale Net Not Part Of Disposal Group LoansReceivableHeldForSaleNetNotPartOfDisposalGroup	1340000
CY2020Q4	us-gaap	Loans Receivable Held For Sale Net Not Part Of Disposal Group LoansReceivableHeldForSaleNetNotPartOfDisposalGroup	1622000
CY2021Q2	us-gaap	Loans And Leases Receivable Gross Carrying Amount LoansAndLeasesReceivableGrossCarryingAmount	7244147000
CY2020Q4	us-gaap	Loans And Leases Receivable Gross Carrying Amount LoansAndLeasesReceivableGrossCarryingAmount	7415952000
CY2021Q2	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	51750000
CY2020Q4	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	60869000
CY2021Q2	us-gaap	Loans And Leases Receivable Net Reported Amount LoansAndLeasesReceivableNetReportedAmount	7192397000
CY2020Q4	us-gaap	Loans And Leases Receivable Net Reported Amount LoansAndLeasesReceivableNetReportedAmount	7355083000
CY2021Q2	us-gaap	Goodwill Goodwill	794892000
CY2020Q4	us-gaap	Goodwill Goodwill	793708000
CY2021Q2	cbu	Core Deposit Intangibles Net CoreDepositIntangiblesNet	11267000
CY2020Q4	cbu	Core Deposit Intangibles Net CoreDepositIntangiblesNet	13831000
CY2021Q2	cbu	Other Finite Lived Intangible Assets Net OtherFiniteLivedIntangibleAssetsNet	36513000
CY2020Q4	cbu	Other Finite Lived Intangible Assets Net OtherFiniteLivedIntangibleAssetsNet	39109000
CY2021Q2	cbu	Intangible Assets Net IntangibleAssetsNet	842672000
CY2020Q4	cbu	Intangible Assets Net IntangibleAssetsNet	846648000
CY2021Q2	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	161007000
CY2020Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	165655000
CY2021Q2	us-gaap	Interest Receivable InterestReceivable	36954000
CY2020Q4	us-gaap	Interest Receivable InterestReceivable	39031000
CY2021Q2	us-gaap	Other Assets OtherAssets	303329000
CY2020Q4	us-gaap	Other Assets OtherAssets	281903000
CY2021Q2	us-gaap	Assets Assets	14801287000
CY2020Q4	us-gaap	Assets Assets	13931094000
CY2021Q2	us-gaap	Noninterest Bearing Deposit Liabilities NoninterestBearingDepositLiabilities	3729355000
CY2020Q4	us-gaap	Noninterest Bearing Deposit Liabilities NoninterestBearingDepositLiabilities	3361768000
CY2021Q2	us-gaap	Interest Bearing Deposit Liabilities InterestBearingDepositLiabilities	8609670000
CY2020Q4	us-gaap	Interest Bearing Deposit Liabilities InterestBearingDepositLiabilities	7863206000
CY2021Q2	us-gaap	Deposits Deposits	12339025000
CY2020Q4	us-gaap	Deposits Deposits	11224974000
CY2021Q2	us-gaap	Securities Sold Under Agreements To Repurchase SecuritiesSoldUnderAgreementsToRepurchase	194887000
CY2020Q4	us-gaap	Securities Sold Under Agreements To Repurchase SecuritiesSoldUnderAgreementsToRepurchase	284008000
CY2021Q2	us-gaap	Federal Home Loan Bank Advances Long Term FederalHomeLoanBankAdvancesLongTerm	2936000
CY2020Q4	us-gaap	Federal Home Loan Bank Advances Long Term FederalHomeLoanBankAdvancesLongTerm	6658000
CY2021Q2	us-gaap	Junior Subordinated Notes JuniorSubordinatedNotes	3290000
CY2020Q4	us-gaap	Junior Subordinated Notes JuniorSubordinatedNotes	3303000
CY2021Q2	us-gaap	Junior Subordinated Debenture Owed To Unconsolidated Subsidiary Trust JuniorSubordinatedDebentureOwedToUnconsolidatedSubsidiaryTrust	0
CY2020Q4	us-gaap	Junior Subordinated Debenture Owed To Unconsolidated Subsidiary Trust JuniorSubordinatedDebentureOwedToUnconsolidatedSubsidiaryTrust	77320000
CY2021Q2	cbu	Accrued Interest And Other Liabilities AccruedInterestAndOtherLiabilities	200049000
CY2020Q4	cbu	Accrued Interest And Other Liabilities AccruedInterestAndOtherLiabilities	230724000
CY2021Q2	us-gaap	Liabilities Liabilities	12740187000
CY2020Q4	us-gaap	Liabilities Liabilities	11826987000
CY2021Q2	us-gaap	Preferred Stock Par Or Stated Value Per Share PreferredStockParOrStatedValuePerShare	1.00
CY2020Q4	us-gaap	Preferred Stock Par Or Stated Value Per Share PreferredStockParOrStatedValuePerShare	1.00
CY2021Q2	us-gaap	Preferred Stock Shares Authorized PreferredStockSharesAuthorized	500000
CY2020Q4	us-gaap	Preferred Stock Shares Authorized PreferredStockSharesAuthorized	500000
CY2021Q2	us-gaap	Preferred Stock Shares Issued PreferredStockSharesIssued	0
CY2020Q4	us-gaap	Preferred Stock Shares Issued PreferredStockSharesIssued	0
CY2021Q2	us-gaap	Preferred Stock Value Outstanding PreferredStockValueOutstanding	0
CY2020Q4	us-gaap	Preferred Stock Value Outstanding PreferredStockValueOutstanding	0
CY2021Q2	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	1.00
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CY2021Q2	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	75000000
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CY2021Q2	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	54063867
CY2020Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	53754599
CY2021Q2	us-gaap	Common Stock Value Outstanding CommonStockValueOutstanding	54064000
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CY2021Q2	us-gaap	Additional Paid In Capital AdditionalPaidInCapital	1037088000
CY2020Q4	us-gaap	Additional Paid In Capital AdditionalPaidInCapital	1025163000
CY2021Q2	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	1015742000
CY2020Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	960183000
CY2021Q2	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-48400000
CY2020Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	62077000
CY2021Q2	us-gaap	Treasury Stock Shares TreasuryStockShares	145172
CY2021Q2	us-gaap	Deferred Compensation Arrangement With Individual Common Stock Reserved For Future Issuance DeferredCompensationArrangementWithIndividualCommonStockReservedForFutureIssuance	145157
CY2020Q4	us-gaap	Treasury Stock Shares TreasuryStockShares	161472
CY2020Q4	us-gaap	Deferred Compensation Arrangement With Individual Common Stock Reserved For Future Issuance DeferredCompensationArrangementWithIndividualCommonStockReservedForFutureIssuance	161457
CY2021Q2	us-gaap	Treasury Stock Value TreasuryStockValue	5632000
CY2020Q4	us-gaap	Treasury Stock Value TreasuryStockValue	6198000
CY2021Q2	us-gaap	Deferred Compensation Arrangement With Individual Common Stock Reserved For Future Issuance DeferredCompensationArrangementWithIndividualCommonStockReservedForFutureIssuance	145157
CY2020Q4	us-gaap	Deferred Compensation Arrangement With Individual Common Stock Reserved For Future Issuance DeferredCompensationArrangementWithIndividualCommonStockReservedForFutureIssuance	161457
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CY2020Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	13931094000
CY2021Q2	us-gaap	Interest And Fee Income Loans And Leases InterestAndFeeIncomeLoansAndLeases	75907000
CY2020Q2	us-gaap	Interest And Fee Income Loans And Leases InterestAndFeeIncomeLoansAndLeases	78720000
	us-gaap	Interest And Fee Income Loans And Leases InterestAndFeeIncomeLoansAndLeases	155621000
	us-gaap	Interest And Fee Income Loans And Leases InterestAndFeeIncomeLoansAndLeases	157285000
CY2021Q2	us-gaap	Interest Income Securities Taxable InterestIncomeSecuritiesTaxable	16789000
CY2020Q2	us-gaap	Interest Income Securities Taxable InterestIncomeSecuritiesTaxable	15423000
	us-gaap	Interest Income Securities Taxable InterestIncomeSecuritiesTaxable	31964000
	us-gaap	Interest Income Securities Taxable InterestIncomeSecuritiesTaxable	30752000
CY2021Q2	us-gaap	Interest Income Securities Tax Exempt InterestIncomeSecuritiesTaxExempt	2664000
CY2020Q2	us-gaap	Interest Income Securities Tax Exempt InterestIncomeSecuritiesTaxExempt	3049000
	us-gaap	Interest Income Securities Tax Exempt InterestIncomeSecuritiesTaxExempt	5440000
	us-gaap	Interest Income Securities Tax Exempt InterestIncomeSecuritiesTaxExempt	6150000
CY2021Q2	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	95360000
CY2020Q2	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	97192000
	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	193025000
	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	194187000
CY2021Q2	us-gaap	Interest Expense Deposits InterestExpenseDeposits	2963000
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	us-gaap	Interest Expense Deposits InterestExpenseDeposits	6075000
	us-gaap	Interest Expense Deposits InterestExpenseDeposits	9718000
CY2021Q2	cbu	Interest Expense Borrowings Excluding Junior Subordinated Debenture Owed To Unconsolidated Subsidiary Trust InterestExpenseBorrowingsExcludingJuniorSubordinatedDebentureOwedToUnconsolidatedSubsidiaryTrust	253000
CY2020Q2	cbu	Interest Expense Borrowings Excluding Junior Subordinated Debenture Owed To Unconsolidated Subsidiary Trust InterestExpenseBorrowingsExcludingJuniorSubordinatedDebentureOwedToUnconsolidatedSubsidiaryTrust	430000
	cbu	Interest Expense Borrowings Excluding Junior Subordinated Debenture Owed To Unconsolidated Subsidiary Trust InterestExpenseBorrowingsExcludingJuniorSubordinatedDebentureOwedToUnconsolidatedSubsidiaryTrust	521000
	cbu	Interest Expense Borrowings Excluding Junior Subordinated Debenture Owed To Unconsolidated Subsidiary Trust InterestExpenseBorrowingsExcludingJuniorSubordinatedDebentureOwedToUnconsolidatedSubsidiaryTrust	988000
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	us-gaap	Interest Expense Subordinated Notes And Debentures InterestExpenseSubordinatedNotesAndDebentures	77000
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CY2021Q2	us-gaap	Interest Expense Junior Subordinated Debentures InterestExpenseJuniorSubordinatedDebentures	0
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	us-gaap	Interest Expense Junior Subordinated Debentures InterestExpenseJuniorSubordinatedDebentures	293000
	us-gaap	Interest Expense Junior Subordinated Debentures InterestExpenseJuniorSubordinatedDebentures	1107000
CY2021Q2	us-gaap	Interest Expense InterestExpense	3255000
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	us-gaap	Interest Expense InterestExpense	6966000
	us-gaap	Interest Expense InterestExpense	12182000
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CY2020Q2	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	91951000
	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	186059000
	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	182005000
CY2021Q2	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	-4338000
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	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	15368000
CY2021Q2	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	96443000
CY2020Q2	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	82177000
	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	196116000
	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	166637000
CY2021Q2	cbu	Deposit Service Fees DepositServiceFees	14236000
CY2020Q2	cbu	Deposit Service Fees DepositServiceFees	12179000
	cbu	Deposit Service Fees DepositServiceFees	28316000
	cbu	Deposit Service Fees DepositServiceFees	28462000
CY2021Q2	cbu	Mortgage Banking MortgageBanking	331000
CY2020Q2	cbu	Mortgage Banking MortgageBanking	1375000
	cbu	Mortgage Banking MortgageBanking	1019000
	cbu	Mortgage Banking MortgageBanking	2291000
CY2021Q2	cbu	Other Banking Services OtherBankingServices	980000
CY2020Q2	cbu	Other Banking Services OtherBankingServices	755000
	cbu	Other Banking Services OtherBankingServices	1834000
	cbu	Other Banking Services OtherBankingServices	1650000
CY2021Q2	cbu	Employee Benefit Services EmployeeBenefitServices	27477000
CY2020Q2	cbu	Employee Benefit Services EmployeeBenefitServices	24068000
	cbu	Employee Benefit Services EmployeeBenefitServices	54010000
	cbu	Employee Benefit Services EmployeeBenefitServices	49434000
CY2021Q2	us-gaap	Insurance Services Revenue InsuranceServicesRevenue	8209000
CY2020Q2	us-gaap	Insurance Services Revenue InsuranceServicesRevenue	8183000
	us-gaap	Insurance Services Revenue InsuranceServicesRevenue	16362000
	us-gaap	Insurance Services Revenue InsuranceServicesRevenue	16241000
CY2021Q2	cbu	Wealth Management Services WealthManagementServices	8227000
CY2020Q2	cbu	Wealth Management Services WealthManagementServices	6366000
	cbu	Wealth Management Services WealthManagementServices	16426000
	cbu	Wealth Management Services WealthManagementServices	13500000
CY2021Q2	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	0
CY2020Q2	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	12000
	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	24000
	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	-18000
CY2021Q2	us-gaap	Noninterest Income NoninterestIncome	59460000
CY2020Q2	us-gaap	Noninterest Income NoninterestIncome	52938000
	us-gaap	Noninterest Income NoninterestIncome	117991000
	us-gaap	Noninterest Income NoninterestIncome	111560000
CY2021Q2	us-gaap	Labor And Related Expense LaborAndRelatedExpense	57892000
CY2020Q2	us-gaap	Labor And Related Expense LaborAndRelatedExpense	54721000
	us-gaap	Labor And Related Expense LaborAndRelatedExpense	115524000
	us-gaap	Labor And Related Expense LaborAndRelatedExpense	112972000
CY2021Q2	us-gaap	Occupancy Net OccupancyNet	10270000
CY2020Q2	us-gaap	Occupancy Net OccupancyNet	9754000
	us-gaap	Occupancy Net OccupancyNet	21570000
	us-gaap	Occupancy Net OccupancyNet	20493000
CY2021Q2	us-gaap	Communications And Information Technology CommunicationsAndInformationTechnology	12766000
CY2020Q2	us-gaap	Communications And Information Technology CommunicationsAndInformationTechnology	10833000
	us-gaap	Communications And Information Technology CommunicationsAndInformationTechnology	25157000
	us-gaap	Communications And Information Technology CommunicationsAndInformationTechnology	21246000
CY2021Q2	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	3246000
CY2020Q2	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	3524000
	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	6597000
	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	7191000
CY2021Q2	us-gaap	Professional Fees ProfessionalFees	2499000
CY2020Q2	us-gaap	Professional Fees ProfessionalFees	3061000
	us-gaap	Professional Fees ProfessionalFees	5533000
	us-gaap	Professional Fees ProfessionalFees	6212000
CY2021Q2	us-gaap	Business Development BusinessDevelopment	2659000
CY2020Q2	us-gaap	Business Development BusinessDevelopment	1504000
	us-gaap	Business Development BusinessDevelopment	4689000
	us-gaap	Business Development BusinessDevelopment	4017000
CY2021Q2	us-gaap	Business Combination Acquisition Related Costs BusinessCombinationAcquisitionRelatedCosts	4000
CY2020Q2	us-gaap	Business Combination Acquisition Related Costs BusinessCombinationAcquisitionRelatedCosts	3372000
	us-gaap	Business Combination Acquisition Related Costs BusinessCombinationAcquisitionRelatedCosts	31000
	us-gaap	Business Combination Acquisition Related Costs BusinessCombinationAcquisitionRelatedCosts	3741000
CY2021Q2	us-gaap	Other Noninterest Expense OtherNoninterestExpense	4207000
CY2020Q2	us-gaap	Other Noninterest Expense OtherNoninterestExpense	4134000
	us-gaap	Other Noninterest Expense OtherNoninterestExpense	7688000
	us-gaap	Other Noninterest Expense OtherNoninterestExpense	8694000
CY2021Q2	us-gaap	Noninterest Expense NoninterestExpense	93543000
CY2020Q2	us-gaap	Noninterest Expense NoninterestExpense	90903000
	us-gaap	Noninterest Expense NoninterestExpense	186789000
	us-gaap	Noninterest Expense NoninterestExpense	184566000
CY2021Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	62360000
CY2020Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	44212000
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	127318000
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	93631000
CY2021Q2	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	14416000
CY2020Q2	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	8964000
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	26524000
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	18249000
CY2021Q2	us-gaap	Net Income Loss NetIncomeLoss	47944000
CY2020Q2	us-gaap	Net Income Loss NetIncomeLoss	35248000
	us-gaap	Net Income Loss NetIncomeLoss	100794000
	us-gaap	Net Income Loss NetIncomeLoss	75382000
CY2021Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.89
CY2020Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.67
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.86
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.44
CY2021Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.88
CY2020Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.66
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.85
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.43
CY2021Q2	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossBeforeTax	-911000
CY2020Q2	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossBeforeTax	-820000
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossBeforeTax	-1822000
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossBeforeTax	-1640000
CY2021Q2	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossTax	-219000
CY2020Q2	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossTax	-197000
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossTax	-438000
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossTax	-394000
CY2021Q2	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossNetOfTax	-692000
CY2020Q2	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossNetOfTax	-623000
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossNetOfTax	-1384000
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossNetOfTax	-1246000
CY2021Q2	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Before Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditBeforeTax	50000
CY2020Q2	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Before Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditBeforeTax	16000
	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Before Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditBeforeTax	100000
	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Before Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditBeforeTax	31000
CY2021Q2	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditTax	12000
CY2020Q2	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditTax	4000
	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditTax	24000
	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditTax	7000
CY2021Q2	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Net Of Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditNetOfTax	38000
CY2020Q2	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Net Of Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditNetOfTax	12000
	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Net Of Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditNetOfTax	76000
	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Net Of Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditNetOfTax	24000
CY2021Q2	us-gaap	Other Comprehensive Income Defined Benefit Plans Adjustment Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentNetOfTaxPortionAttributableToParent	-730000
CY2020Q2	us-gaap	Other Comprehensive Income Defined Benefit Plans Adjustment Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentNetOfTaxPortionAttributableToParent	-635000
	us-gaap	Other Comprehensive Income Defined Benefit Plans Adjustment Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentNetOfTaxPortionAttributableToParent	-1460000
	us-gaap	Other Comprehensive Income Defined Benefit Plans Adjustment Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentNetOfTaxPortionAttributableToParent	-1270000
CY2021Q2	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	80074000
CY2020Q2	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	7832000
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	-147353000
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	130260000
CY2021Q2	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	19247000
CY2020Q2	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	1880000
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	-35416000
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	31273000
CY2021Q2	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	60827000
CY2020Q2	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	5952000
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-111937000
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	98987000
CY2021Q2	us-gaap	Other Comprehensive Income Availableforsale Securities Adjustment Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentNetOfTaxPortionAttributableToParent	60827000
CY2020Q2	us-gaap	Other Comprehensive Income Availableforsale Securities Adjustment Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentNetOfTaxPortionAttributableToParent	5952000
	us-gaap	Other Comprehensive Income Availableforsale Securities Adjustment Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentNetOfTaxPortionAttributableToParent	-111937000
	us-gaap	Other Comprehensive Income Availableforsale Securities Adjustment Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentNetOfTaxPortionAttributableToParent	98987000
CY2021Q2	cbu	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent Including Cumulative Effect Of Change In Accounting Principle OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParentIncludingCumulativeEffectOfChangeInAccountingPrinciple	61557000
CY2020Q2	cbu	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent Including Cumulative Effect Of Change In Accounting Principle OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParentIncludingCumulativeEffectOfChangeInAccountingPrinciple	6587000
	cbu	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent Including Cumulative Effect Of Change In Accounting Principle OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParentIncludingCumulativeEffectOfChangeInAccountingPrinciple	-110477000
	cbu	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent Including Cumulative Effect Of Change In Accounting Principle OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParentIncludingCumulativeEffectOfChangeInAccountingPrinciple	100257000
CY2021Q2	us-gaap	Net Income Loss NetIncomeLoss	47944000
CY2020Q2	us-gaap	Net Income Loss NetIncomeLoss	35248000
	us-gaap	Net Income Loss NetIncomeLoss	100794000
	us-gaap	Net Income Loss NetIncomeLoss	75382000
CY2021Q2	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	109501000
CY2020Q2	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	41835000
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	-9683000
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	175639000
CY2021Q2	cbu	Accumulated Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Gross Of Tax AccumulatedOtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansGrossOfTax	36345000
CY2020Q4	cbu	Accumulated Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Gross Of Tax AccumulatedOtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansGrossOfTax	38267000
CY2021Q2	cbu	Accumulated Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax Effect AccumulatedOtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTaxEffect	-8932000
CY2020Q4	cbu	Accumulated Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax Effect AccumulatedOtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTaxEffect	-9394000
CY2021Q2	us-gaap	Accumulated Other Comprehensive Income Loss Defined Benefit Pension And Other Postretirement Plans Net Of Tax AccumulatedOtherComprehensiveIncomeLossDefinedBenefitPensionAndOtherPostretirementPlansNetOfTax	27413000
CY2020Q4	us-gaap	Accumulated Other Comprehensive Income Loss Defined Benefit Pension And Other Postretirement Plans Net Of Tax AccumulatedOtherComprehensiveIncomeLossDefinedBenefitPensionAndOtherPostretirementPlansNetOfTax	28873000
CY2021Q2	cbu	Accumulated Other Comprehensive Income Loss Available For Sale Securities Adjustment Gross AccumulatedOtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentGross	-27239000
CY2020Q4	cbu	Accumulated Other Comprehensive Income Loss Available For Sale Securities Adjustment Gross AccumulatedOtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentGross	120114000
CY2021Q2	cbu	Accumulated Other Comprehensive Income Loss Available For Sale Securities Adjustment Tax Effect AccumulatedOtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentTaxEffect	-6252000
CY2020Q4	cbu	Accumulated Other Comprehensive Income Loss Available For Sale Securities Adjustment Tax Effect AccumulatedOtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentTaxEffect	29164000
CY2021Q2	us-gaap	Accumulated Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax AccumulatedOtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	-20987000
CY2020Q4	us-gaap	Accumulated Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax AccumulatedOtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	90950000
CY2021Q2	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-48400000
CY2020Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	62077000
CY2021Q1	us-gaap	Stockholders Equity StockholdersEquity	1971397000
CY2021Q2	us-gaap	Net Income Loss NetIncomeLoss	47944000
CY2021Q2	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	61557000
CY2021Q2	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.42
CY2021Q2	us-gaap	Dividends Common Stock DividendsCommonStock	22706000
CY2021Q2	cbu	Stock Issued During Period Value Employee Stock Ownership Plan Net Of Impact Of Net Settlement Of Tax Withholding Obligations StockIssuedDuringPeriodValueEmployeeStockOwnershipPlanNetOfImpactOfNetSettlementOfTaxWithholdingObligations	1340000
CY2021Q2	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	1568000
CY2021Q2	us-gaap	Stock Issued During Period Value Employee Benefit Plan StockIssuedDuringPeriodValueEmployeeBenefitPlan	0
CY2021Q2	us-gaap	Stockholders Equity StockholdersEquity	2061100000
CY2020Q1	us-gaap	Stockholders Equity StockholdersEquity	1976631000
CY2020Q2	us-gaap	Net Income Loss NetIncomeLoss	35248000
CY2020Q2	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	6587000
CY2020Q2	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.41
CY2020Q2	us-gaap	Dividends Common Stock DividendsCommonStock	22004000
CY2020Q2	cbu	Stock Issued During Period Value Employee Stock Ownership Plan Net Of Impact Of Net Settlement Of Tax Withholding Obligations StockIssuedDuringPeriodValueEmployeeStockOwnershipPlanNetOfImpactOfNetSettlementOfTaxWithholdingObligations	6624000
	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	15368000
	us-gaap	Amortization Of Mortgage Servicing Rights Ms Rs AmortizationOfMortgageServicingRightsMSRs	269000
	us-gaap	Amortization Of Mortgage Servicing Rights Ms Rs AmortizationOfMortgageServicingRightsMSRs	166000
	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	24000
	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	-18000
	us-gaap	Bank Owned Life Insurance Income BankOwnedLifeInsuranceIncome	981000
	us-gaap	Bank Owned Life Insurance Income BankOwnedLifeInsuranceIncome	866000
CY2020Q2	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	1281000
CY2020Q2	us-gaap	Stock Issued During Period Value Acquisitions StockIssuedDuringPeriodValueAcquisitions	76942000
CY2020Q2	us-gaap	Stock Issued During Period Value Employee Benefit Plan StockIssuedDuringPeriodValueEmployeeBenefitPlan	6000
CY2020Q2	us-gaap	Stockholders Equity StockholdersEquity	2081315000
CY2020Q4	us-gaap	Stockholders Equity StockholdersEquity	2104107000
	us-gaap	Net Income Loss NetIncomeLoss	100794000
	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-110477000
	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.84
	us-gaap	Dividends Common Stock DividendsCommonStock	45235000
	cbu	Stock Issued During Period Value Employee Stock Ownership Plan Net Of Impact Of Net Settlement Of Tax Withholding Obligations StockIssuedDuringPeriodValueEmployeeStockOwnershipPlanNetOfImpactOfNetSettlementOfTaxWithholdingObligations	8669000
	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	3242000
	cbu	Stock Issued During Period Value Deferred Compensation Arrangements StockIssuedDuringPeriodValueDeferredCompensationArrangements	0
	us-gaap	Stock Issued During Period Value Employee Benefit Plan StockIssuedDuringPeriodValueEmployeeBenefitPlan	0
CY2021Q2	us-gaap	Stockholders Equity StockholdersEquity	2061100000
CY2019Q4	us-gaap	Stockholders Equity StockholdersEquity	1855234000
	us-gaap	Net Income Loss NetIncomeLoss	75382000
	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	100257000
	cbu	Cummulative Effect Of Change Accounting Principle CummulativeEffectOfChangeAccountingPrinciple	530000
	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.82
	us-gaap	Dividends Common Stock DividendsCommonStock	43371000
	cbu	Stock Issued During Period Value Employee Stock Ownership Plan Net Of Impact Of Net Settlement Of Tax Withholding Obligations StockIssuedDuringPeriodValueEmployeeStockOwnershipPlanNetOfImpactOfNetSettlementOfTaxWithholdingObligations	13023000
	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	3233000
	us-gaap	Stock Issued During Period Value Acquisitions StockIssuedDuringPeriodValueAcquisitions	76942000
	cbu	Stock Issued During Period Value Deferred Compensation Arrangements StockIssuedDuringPeriodValueDeferredCompensationArrangements	0
	us-gaap	Stock Issued During Period Value Employee Benefit Plan StockIssuedDuringPeriodValueEmployeeBenefitPlan	85000
CY2020Q2	us-gaap	Stockholders Equity StockholdersEquity	2081315000
	us-gaap	Net Income Loss NetIncomeLoss	100794000
	us-gaap	Net Income Loss NetIncomeLoss	75382000
	us-gaap	Depreciation Depreciation	8014000
	us-gaap	Depreciation Depreciation	7995000
	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	6597000
	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	7191000
	cbu	Accretion Amortization On Investments Loans And Borrowings AccretionAmortizationOnInvestmentsLoansAndBorrowings	11729000
	cbu	Accretion Amortization On Investments Loans And Borrowings AccretionAmortizationOnInvestmentsLoansAndBorrowings	5902000
	us-gaap	Share Based Compensation ShareBasedCompensation	3242000
	us-gaap	Share Based Compensation ShareBasedCompensation	3233000
	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	-10057000
	cbu	Net Gain Loss On Sale Of Loans And Other Assets NetGainLossOnSaleOfLoansAndOtherAssets	463000
	cbu	Net Gain Loss On Sale Of Loans And Other Assets NetGainLossOnSaleOfLoansAndOtherAssets	529000
	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	7585000
	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	6701000
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	88077000
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	95355000
	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	151994000
	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	130739000
	us-gaap	Proceeds From Maturities Prepayments And Calls Of Other Investments ProceedsFromMaturitiesPrepaymentsAndCallsOfOtherInvestments	2648000
	us-gaap	Proceeds From Maturities Prepayments And Calls Of Other Investments ProceedsFromMaturitiesPrepaymentsAndCallsOfOtherInvestments	406000
	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	759022000
	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	65211000
	cbu	Payments To Acquire Equity And Other Securities PaymentsToAcquireEquityAndOtherSecurities	92000
	cbu	Payments To Acquire Equity And Other Securities PaymentsToAcquireEquityAndOtherSecurities	24000
	us-gaap	Payments For Proceeds From Loans And Leases PaymentsForProceedsFromLoansAndLeases	-179167000
	us-gaap	Payments For Proceeds From Loans And Leases PaymentsForProceedsFromLoansAndLeases	296873000
	us-gaap	Cash Acquired From Acquisition CashAcquiredFromAcquisition	0
	us-gaap	Cash Acquired From Acquisition CashAcquiredFromAcquisition	55973000
	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	2900000
	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	-34360000
	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	5689000
	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	4641000
	us-gaap	Payments For Proceeds From Real Estate Partnership Investment Net PaymentsForProceedsFromRealEstatePartnershipInvestmentNet	320000
	us-gaap	Payments For Proceeds From Real Estate Partnership Investment Net PaymentsForProceedsFromRealEstatePartnershipInvestmentNet	550000
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-434214000
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-201794000
	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	1114051000
	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	1335437000
	us-gaap	Proceeds From Repayments Of Debt ProceedsFromRepaymentsOfDebt	-92843000
	us-gaap	Proceeds From Repayments Of Debt ProceedsFromRepaymentsOfDebt	-83563000
	cbu	Repayments Of Subordinated Debt Held By Unconsolidated Subsidiary Trusts RepaymentsOfSubordinatedDebtHeldByUnconsolidatedSubsidiaryTrusts	77320000
	cbu	Repayments Of Subordinated Debt Held By Unconsolidated Subsidiary Trusts RepaymentsOfSubordinatedDebtHeldByUnconsolidatedSubsidiaryTrusts	0
	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	8669000
	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	13023000
	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	128000
	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	139000
	us-gaap	Proceeds From Sale Of Treasury Stock ProceedsFromSaleOfTreasuryStock	0
	us-gaap	Proceeds From Sale Of Treasury Stock ProceedsFromSaleOfTreasuryStock	85000
	us-gaap	Increase Decrease In Deferred Compensation IncreaseDecreaseInDeferredCompensation	128000
	us-gaap	Increase Decrease In Deferred Compensation IncreaseDecreaseInDeferredCompensation	139000
	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	45162000
	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	42609000
	us-gaap	Excess Tax Benefit From Share Based Compensation Financing Activities ExcessTaxBenefitFromShareBasedCompensationFinancingActivities	-1137000
	us-gaap	Excess Tax Benefit From Share Based Compensation Financing Activities ExcessTaxBenefitFromShareBasedCompensationFinancingActivities	-1084000
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	906258000
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	1221289000
	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	560121000
	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	1114850000
CY2020Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	1645805000
CY2019Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	205030000
CY2021Q2	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	2205926000
CY2020Q2	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	1319880000
	us-gaap	Interest Paid Net InterestPaidNet	7644000
	us-gaap	Interest Paid Net InterestPaidNet	12336000
	us-gaap	Income Taxes Paid IncomeTaxesPaid	22482000
	us-gaap	Income Taxes Paid IncomeTaxesPaid	10459000
	us-gaap	Transfer To Other Real Estate TransferToOtherRealEstate	990000
	us-gaap	Stock Issued1 StockIssued1	0
	us-gaap	Stock Issued1 StockIssued1	76942000
CY2021Q2	us-gaap	Dividends Payable Current And Noncurrent DividendsPayableCurrentAndNoncurrent	22768000
CY2020Q2	us-gaap	Dividends Payable Current And Noncurrent DividendsPayableCurrentAndNoncurrent	22104000
	us-gaap	Transfer To Other Real Estate TransferToOtherRealEstate	120000
	us-gaap	Fair Value Of Assets Acquired FairValueOfAssetsAcquired	199000
	us-gaap	Fair Value Of Assets Acquired FairValueOfAssetsAcquired	549983000
	us-gaap	Liabilities Assumed1 LiabilitiesAssumed1	174000
	us-gaap	Liabilities Assumed1 LiabilitiesAssumed1	530767000
CY2020Q2	us-gaap	Business Combination Acquisition Related Costs BusinessCombinationAcquisitionRelatedCosts	3400000
	us-gaap	Business Combination Acquisition Related Costs BusinessCombinationAcquisitionRelatedCosts	3700000
CY2020Q2	cbu	Business Acquisitions Pro Forma Acquisition Related Expenses BusinessAcquisitionsProFormaAcquisitionRelatedExpenses	3300000
	cbu	Business Acquisitions Pro Forma Acquisition Related Expenses BusinessAcquisitionsProFormaAcquisitionRelatedExpenses	3600000
CY2020Q2	us-gaap	Business Acquisitions Pro Forma Revenue BusinessAcquisitionsProFormaRevenue	149576000
CY2019Q2	us-gaap	Business Acquisitions Pro Forma Revenue BusinessAcquisitionsProFormaRevenue	154878000
	us-gaap	Business Acquisitions Pro Forma Revenue BusinessAcquisitionsProFormaRevenue	304088000
	us-gaap	Business Acquisitions Pro Forma Revenue BusinessAcquisitionsProFormaRevenue	303152000
CY2020Q2	us-gaap	Business Acquisitions Pro Forma Net Income Loss BusinessAcquisitionsProFormaNetIncomeLoss	39072000
CY2019Q2	us-gaap	Business Acquisitions Pro Forma Net Income Loss BusinessAcquisitionsProFormaNetIncomeLoss	46447000
	us-gaap	Business Acquisitions Pro Forma Net Income Loss BusinessAcquisitionsProFormaNetIncomeLoss	80848000
	us-gaap	Business Acquisitions Pro Forma Net Income Loss BusinessAcquisitionsProFormaNetIncomeLoss	86774000
CY2021Q2	us-gaap	Contract With Customer Asset Net ContractWithCustomerAssetNet	27400000
CY2021Q2	us-gaap	Unbilled Contracts Receivable UnbilledContractsReceivable	8300000
CY2021Q2	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	2700000
CY2020Q4	us-gaap	Contract With Customer Asset Net ContractWithCustomerAssetNet	30300000
CY2020Q4	us-gaap	Unbilled Contracts Receivable UnbilledContractsReceivable	7700000
CY2020Q4	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	1400000
CY2021Q2	us-gaap	Available For Sale Securities Amortized Cost AvailableForSaleSecuritiesAmortizedCost	4039978000
CY2021Q2	us-gaap	Available For Sale Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	85757000
CY2021Q2	us-gaap	Available For Sale Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	112996000
CY2021Q2	us-gaap	Available For Sale Securities AvailableForSaleSecurities	4012739000
CY2020Q4	us-gaap	Available For Sale Securities Amortized Cost AvailableForSaleSecuritiesAmortizedCost	3427779000
CY2020Q4	us-gaap	Available For Sale Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	136901000
CY2020Q4	us-gaap	Available For Sale Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	16788000
CY2020Q4	us-gaap	Available For Sale Securities AvailableForSaleSecurities	3547892000
CY2021Q2	us-gaap	Equity Securities Fv Ni Cost EquitySecuritiesFvNiCost	251000
CY2021Q2	cbu	Equity Securities Fv Ni Accumulated Gross Unrealized Gain Before Tax EquitySecuritiesFvNiAccumulatedGrossUnrealizedGainBeforeTax	218000
CY2021Q2	cbu	Equity Securities Fv Ni Accumulated Gross Unrealized Loss Before Tax EquitySecuritiesFvNiAccumulatedGrossUnrealizedLossBeforeTax	0
CY2021Q2	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	469000
CY2020Q4	us-gaap	Equity Securities Fv Ni Cost EquitySecuritiesFvNiCost	251000
CY2020Q4	cbu	Equity Securities Fv Ni Accumulated Gross Unrealized Gain Before Tax EquitySecuritiesFvNiAccumulatedGrossUnrealizedGainBeforeTax	194000
CY2020Q4	cbu	Equity Securities Fv Ni Accumulated Gross Unrealized Loss Before Tax EquitySecuritiesFvNiAccumulatedGrossUnrealizedLossBeforeTax	0
CY2020Q4	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	445000
CY2021Q2	cbu	Other Investments And Equity Securities At Cost OtherInvestmentsAndEquitySecuritiesAtCost	43955000
CY2021Q2	cbu	Other Investments And Equity Securities Accumulated Gross Unrealized Gain Before Tax OtherInvestmentsAndEquitySecuritiesAccumulatedGrossUnrealizedGainBeforeTax	968000
CY2021Q2	cbu	Other Investments And Equity Securities Accumulated Gross Unrealized Loss Before Tax OtherInvestmentsAndEquitySecuritiesAccumulatedGrossUnrealizedLossBeforeTax	0
CY2021Q2	cbu	Other Investment And Equity Securities Fair Value OtherInvestmentAndEquitySecuritiesFairValue	44923000
CY2020Q4	cbu	Other Investments And Equity Securities At Cost OtherInvestmentsAndEquitySecuritiesAtCost	46511000
CY2020Q4	cbu	Other Investments And Equity Securities Accumulated Gross Unrealized Gain Before Tax OtherInvestmentsAndEquitySecuritiesAccumulatedGrossUnrealizedGainBeforeTax	944000
CY2020Q4	cbu	Other Investments And Equity Securities Accumulated Gross Unrealized Loss Before Tax OtherInvestmentsAndEquitySecuritiesAccumulatedGrossUnrealizedLossBeforeTax	0
CY2020Q4	cbu	Other Investment And Equity Securities Fair Value OtherInvestmentAndEquitySecuritiesFairValue	47455000
CY2021Q2	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Number Of Positions DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsNumberOfPositions	162
CY2021Q2	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	1446539000
CY2021Q2	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	112993000
CY2021Q2	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Number Of Positions DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerNumberOfPositions	9
CY2021Q2	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	1328000
CY2021Q2	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	3000
CY2021Q2	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Number Of Positions DebtSecuritiesAvailableForSaleUnrealizedLossPositionNumberOfPositions	171
CY2021Q2	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	1447867000
CY2021Q2	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	112996000
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Number Of Positions DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsNumberOfPositions	117
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	913612000
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	16788000
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Number Of Positions DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerNumberOfPositions	3
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	14000
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	0
CY2020Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Number Of Positions DebtSecuritiesAvailableForSaleUnrealizedLossPositionNumberOfPositions	120
CY2020Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	913626000
CY2020Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	16788000
CY2021Q2	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss DebtSecuritiesAvailableForSaleAllowanceForCreditLoss	0
CY2021Q2	us-gaap	Available For Sale Securities Debt Maturities Within One Year Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost	198566000
CY2021Q2	us-gaap	Available For Sale Securities Debt Maturities Within One Year Fair Value AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue	199557000
CY2021Q2	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost	768349000
CY2021Q2	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	796228000
CY2021Q2	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsAmortizedCost	1018820000
CY2021Q2	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	1037749000
CY2021Q2	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAmortizedCost	1504697000
CY2021Q2	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue	1420784000
CY2021Q2	us-gaap	Available For Sale Securities Debt Maturities Single Maturity Date Amortized Cost Basis AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDateAmortizedCostBasis	3490432000
CY2021Q2	us-gaap	Available For Sale Securities Debt Maturities Single Maturity Date AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDate	3454318000
CY2021Q2	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	4039978000
CY2021Q2	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	4012739000
CY2021Q2	us-gaap	Pledged Financial Instruments Not Separately Reported Securities Pledged PledgedFinancialInstrumentsNotSeparatelyReportedSecuritiesPledged	2430000000
CY2020Q4	us-gaap	Pledged Financial Instruments Not Separately Reported Securities Pledged PledgedFinancialInstrumentsNotSeparatelyReportedSecuritiesPledged	2030000000.00
CY2021Q2	us-gaap	Loans And Leases Receivable Gross Carrying Amount LoansAndLeasesReceivableGrossCarryingAmount	7244147000
CY2020Q4	us-gaap	Loans And Leases Receivable Gross Carrying Amount LoansAndLeasesReceivableGrossCarryingAmount	7415952000
CY2021Q2	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	51750000
CY2020Q4	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	60869000
CY2021Q2	us-gaap	Loans And Leases Receivable Net Reported Amount LoansAndLeasesReceivableNetReportedAmount	7192397000
CY2020Q4	us-gaap	Loans And Leases Receivable Net Reported Amount LoansAndLeasesReceivableNetReportedAmount	7355083000
	us-gaap	Financing Receivable Nonaccrual Interest Income FinancingReceivableNonaccrualInterestIncome	0
CY2021Q2	us-gaap	Impaired Financing Receivable With Related Allowance Unpaid Principal Balance ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance	25534000
CY2020Q4	us-gaap	Impaired Financing Receivable With Related Allowance Unpaid Principal Balance ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance	27437000
CY2021Q2	us-gaap	Impaired Financing Receivable With No Related Allowance Unpaid Principal Balance ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance	6529000
CY2020Q4	us-gaap	Impaired Financing Receivable With No Related Allowance Unpaid Principal Balance ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance	8138000
CY2021Q2	us-gaap	Impaired Financing Receivable Unpaid Principal Balance ImpairedFinancingReceivableUnpaidPrincipalBalance	32063000
CY2020Q4	us-gaap	Impaired Financing Receivable Unpaid Principal Balance ImpairedFinancingReceivableUnpaidPrincipalBalance	35575000
CY2021Q2	cbu	Impaired Financing Receivable Contractual Balance ImpairedFinancingReceivableContractualBalance	34228000
CY2020Q4	cbu	Impaired Financing Receivable Contractual Balance ImpairedFinancingReceivableContractualBalance	38362000
CY2021Q2	us-gaap	Impaired Financing Receivable Related Allowance ImpairedFinancingReceivableRelatedAllowance	2800000
CY2020Q4	us-gaap	Impaired Financing Receivable Related Allowance ImpairedFinancingReceivableRelatedAllowance	3874000
CY2021Q2	us-gaap	Impaired Financing Receivable Average Recorded Investment ImpairedFinancingReceivableAverageRecordedInvestment	32900000
CY2020Q2	us-gaap	Impaired Financing Receivable Average Recorded Investment ImpairedFinancingReceivableAverageRecordedInvestment	1400000
	us-gaap	Impaired Financing Receivable Average Recorded Investment ImpairedFinancingReceivableAverageRecordedInvestment	34600000
	us-gaap	Impaired Financing Receivable Average Recorded Investment ImpairedFinancingReceivableAverageRecordedInvestment	1800000
	us-gaap	Impaired Financing Receivable Interest Income Accrual Method ImpairedFinancingReceivableInterestIncomeAccrualMethod	0
	us-gaap	Impaired Financing Receivable Interest Income Accrual Method ImpairedFinancingReceivableInterestIncomeAccrualMethod	0
	cbu	Number Of Borrowers Representing75.6 Million In Outstanding Loan Balances NumberOfBorrowersRepresenting75.6MillionInOutstandingLoanBalances	12
CY2021Q2	cbu	Outstanding Loan Balances Of47 Number Of Borrowers OutstandingLoanBalancesOf47NumberOfBorrowers	2400000
	cbu	Percentage Of Total Loans Outstanding PercentageOfTotalLoansOutstanding	0.0003
	cbu	Number Of Business Borrowers Representing75.1 Million In Outstanding Loan Balances NumberOfBusinessBorrowersRepresenting75.1MillionInOutstandingLoanBalances	8
CY2021Q2	cbu	Outstanding Loan Balances Of42 Number Of Borrowers OutstandingLoanBalancesOf42NumberOfBorrowers	2000000.0
	cbu	Number Of Consumer Borrowers Representing0.5 Million In Outstanding Loan Balances NumberOfConsumerBorrowersRepresenting0.5MillionInOutstandingLoanBalances	4
CY2021Q2	cbu	Outstanding Loan Balances Of5 Number Of Consumer Borrowers OutstandingLoanBalancesOf5NumberOfConsumerBorrowers	400000
CY2020	cbu	Number Of Borrowers Representing66.5 Million In Outstanding Loan Balances NumberOfBorrowersRepresenting66.5MillionInOutstandingLoanBalances	74
CY2020Q4	cbu	Outstanding Loan Balances Of74 Number Of Borrowers OutstandingLoanBalancesOf74NumberOfBorrowers	66500000
CY2020	cbu	Percentage Of Total Loans Outstanding PercentageOfTotalLoansOutstanding	0.009
CY2020	cbu	Number Of Borrowers Representing65.7 Million In Outstanding Loan Balances NumberOfBorrowersRepresenting65.7MillionInOutstandingLoanBalances	63
CY2020Q4	cbu	Outstanding Loan Balances Of63 Number Of Borrowers OutstandingLoanBalancesOf63NumberOfBorrowers	65700000
CY2020	cbu	Number Of Borrowers Representing0.8 Million In Outstanding Loan Balances NumberOfBorrowersRepresenting0.8MillionInOutstandingLoanBalances	11
CY2020Q4	cbu	Outstanding Loan Balances Of11 Number Of Borrowers OutstandingLoanBalancesOf11NumberOfBorrowers	800000
CY2021Q2	cbu	Financing Receivable Modifications Number Of Contracts FinancingReceivableModificationsNumberOfContracts	228
CY2021Q2	us-gaap	Financing Receivable Modifications Recorded Investment FinancingReceivableModificationsRecordedInvestment	6682000
CY2020Q4	cbu	Financing Receivable Modifications Number Of Contracts FinancingReceivableModificationsNumberOfContracts	247
CY2020Q4	us-gaap	Financing Receivable Modifications Recorded Investment FinancingReceivableModificationsRecordedInvestment	6984000
	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	16
	us-gaap	Financing Receivable Modifications Post Modification Recorded Investment2 FinancingReceivableModificationsPostModificationRecordedInvestment2	482000
	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	7
	us-gaap	Financing Receivable Modifications Post Modification Recorded Investment2 FinancingReceivableModificationsPostModificationRecordedInvestment2	249000
CY2021Q1	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	55069000
CY2021Q2	us-gaap	Allowance For Loan And Lease Losses Write Offs AllowanceForLoanAndLeaseLossesWriteOffs	1106000
CY2021Q2	us-gaap	Allowance For Loan And Lease Loss Recovery Of Bad Debts AllowanceForLoanAndLeaseLossRecoveryOfBadDebts	1698000
CY2021Q2	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	-3911000
CY2021Q2	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	51750000
CY2021Q1	us-gaap	Off Balance Sheet Credit Loss Liability OffBalanceSheetCreditLossLiability	1189000
CY2021Q2	cbu	Off Balance Sheet Credit Loss Liability Charge Offs OffBalanceSheetCreditLossLiabilityChargeOffs	0
CY2021Q2	cbu	Off Balance Sheet Credit Loss Liability Recovery OffBalanceSheetCreditLossLiabilityRecovery	0
CY2021Q2	us-gaap	Off Balance Sheet Credit Loss Liability Credit Loss Expense Reversal OffBalanceSheetCreditLossLiabilityCreditLossExpenseReversal	-427000
CY2021Q2	us-gaap	Off Balance Sheet Credit Loss Liability OffBalanceSheetCreditLossLiability	762000
CY2021Q1	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	56258000
CY2021Q2	us-gaap	Financing Receivable Allowance For Credit Losses Write Offs FinancingReceivableAllowanceForCreditLossesWriteOffs	1106000
CY2021Q2	us-gaap	Financing Receivable Allowance For Credit Losses Recovery FinancingReceivableAllowanceForCreditLossesRecovery	1698000
CY2021Q2	cbu	Provision For Loan Lease And Other Losses Excluding Acquisition Related Provision For Credit Losses ProvisionForLoanLeaseAndOtherLossesExcludingAcquisitionRelatedProvisionForCreditLosses	-4338000
CY2021Q2	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	52512000
CY2020Q1	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	55652000
CY2020Q2	us-gaap	Allowance For Loan And Lease Losses Write Offs AllowanceForLoanAndLeaseLossesWriteOffs	2094000
CY2020Q2	us-gaap	Allowance For Loan And Lease Loss Recovery Of Bad Debts AllowanceForLoanAndLeaseLossRecoveryOfBadDebts	1184000
CY2020Q2	us-gaap	Allowance For Loan And Lease Losses Loans Acquired AllowanceForLoanAndLeaseLossesLoansAcquired	3662000
CY2020Q2	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	6033000
CY2020Q2	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	64437000
CY2020Q1	us-gaap	Off Balance Sheet Credit Loss Liability OffBalanceSheetCreditLossLiability	845000
CY2020Q2	cbu	Off Balance Sheet Credit Loss Liability Charge Offs OffBalanceSheetCreditLossLiabilityChargeOffs	0
CY2020Q2	cbu	Off Balance Sheet Credit Loss Liability Recovery OffBalanceSheetCreditLossLiabilityRecovery	0
CY2020Q2	cbu	Off Balance Sheet Credit Loss Liability Acquisition OffBalanceSheetCreditLossLiabilityAcquisition	67000
CY2020Q2	us-gaap	Off Balance Sheet Credit Loss Liability Credit Loss Expense Reversal OffBalanceSheetCreditLossLiabilityCreditLossExpenseReversal	540000
CY2020Q2	us-gaap	Off Balance Sheet Credit Loss Liability OffBalanceSheetCreditLossLiability	1452000
CY2020Q1	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	56497000
CY2020Q2	us-gaap	Financing Receivable Allowance For Credit Losses Write Offs FinancingReceivableAllowanceForCreditLossesWriteOffs	2094000
CY2020Q2	us-gaap	Financing Receivable Allowance For Credit Losses Recovery FinancingReceivableAllowanceForCreditLossesRecovery	1184000
CY2020Q2	cbu	Financing Receivable Allowance For Credit Loss Acquisition FinancingReceivableAllowanceForCreditLossAcquisition	3729000
CY2020Q2	cbu	Provision For Loan Lease And Other Losses Excluding Acquisition Related Provision For Credit Losses ProvisionForLoanLeaseAndOtherLossesExcludingAcquisitionRelatedProvisionForCreditLosses	6573000
CY2020Q2	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	65889000
CY2020Q4	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	60869000
	us-gaap	Allowance For Loan And Lease Losses Write Offs AllowanceForLoanAndLeaseLossesWriteOffs	3072000
	us-gaap	Allowance For Loan And Lease Loss Recovery Of Bad Debts AllowanceForLoanAndLeaseLossRecoveryOfBadDebts	3283000
	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	-9330000
CY2021Q2	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	51750000
CY2020Q4	us-gaap	Off Balance Sheet Credit Loss Liability OffBalanceSheetCreditLossLiability	1489000
	cbu	Off Balance Sheet Credit Loss Liability Charge Offs OffBalanceSheetCreditLossLiabilityChargeOffs	0
	cbu	Off Balance Sheet Credit Loss Liability Recovery OffBalanceSheetCreditLossLiabilityRecovery	0
	us-gaap	Off Balance Sheet Credit Loss Liability Credit Loss Expense Reversal OffBalanceSheetCreditLossLiabilityCreditLossExpenseReversal	-727000
CY2021Q2	us-gaap	Off Balance Sheet Credit Loss Liability OffBalanceSheetCreditLossLiability	762000
CY2020Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	62358000
	us-gaap	Financing Receivable Allowance For Credit Losses Write Offs FinancingReceivableAllowanceForCreditLossesWriteOffs	3072000
	us-gaap	Financing Receivable Allowance For Credit Losses Recovery FinancingReceivableAllowanceForCreditLossesRecovery	3283000
	cbu	Provision For Loan Lease And Other Losses Excluding Acquisition Related Provision For Credit Losses ProvisionForLoanLeaseAndOtherLossesExcludingAcquisitionRelatedProvisionForCreditLosses	-10057000
CY2021Q2	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	52512000
CY2019Q4	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	49911000
CY2019Q4	us-gaap	Off Balance Sheet Credit Loss Liability OffBalanceSheetCreditLossLiability	0
CY2019Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	49911000
CY2021Q2	cbu	Allowance For Credit Losses To Total Loans Ratio AllowanceForCreditLossesToTotalLoansRatio	0.71
	cbu	Allowance For Credit Losses To Total Loans Ratio Basis Spread Lower Than Level AllowanceForCreditLossesToTotalLoansRatioBasisSpreadLowerThanLevel	0.15
CY2020	cbu	Allowance For Credit Losses To Total Loans Ratio Basis Spread Lower Than Level AllowanceForCreditLossesToTotalLoansRatioBasisSpreadLowerThanLevel	0.11
CY2021Q2	us-gaap	Accrued Fees And Other Revenue Receivable AccruedFeesAndOtherRevenueReceivable	19000000.0
	us-gaap	Financing Receivable Significant Purchases FinancingReceivableSignificantPurchases	0
	us-gaap	Financing Receivable Significant Sales FinancingReceivableSignificantSales	11708000
CY2021Q2	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	161302000
CY2021Q2	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	113522000
CY2021Q2	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	47780000
CY2020Q4	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	159865000
CY2020Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	106925000
CY2020Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	52940000
CY2021Q2	us-gaap	Finite Lived Intangible Assets Amortization Expense Remainder Of Fiscal Year FiniteLivedIntangibleAssetsAmortizationExpenseRemainderOfFiscalYear	6229000
CY2021Q2	us-gaap	Finite Lived Intangible Assets Amortization Expense Next Twelve Months FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths	11141000
CY2021Q2	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Two FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo	9338000
CY2021Q2	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Three FiniteLivedIntangibleAssetsAmortizationExpenseYearThree	7768000
CY2021Q2	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Four FiniteLivedIntangibleAssetsAmortizationExpenseYearFour	6550000
CY2021Q2	cbu	Finite Lived Intangible Asset Expected Amortization After Year Four FiniteLivedIntangibleAssetExpectedAmortizationAfterYearFour	6754000
CY2021Q2	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	47780000
CY2020Q4	us-gaap	Goodwill Goodwill	793708000
	us-gaap	Goodwill Period Increase Decrease GoodwillPeriodIncreaseDecrease	1184000
CY2021Q2	us-gaap	Goodwill Goodwill	794892000
CY2020Q2	us-gaap	Defined Benefit Plan Contributions By Employer DefinedBenefitPlanContributionsByEmployer	3900000
CY2021Q2	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	200000
	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	100000
	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	600000
CY2020Q2	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	600000
CY2021Q2	us-gaap	Net Income Loss NetIncomeLoss	47944000
CY2020Q2	us-gaap	Net Income Loss NetIncomeLoss	35248000
	us-gaap	Net Income Loss NetIncomeLoss	100794000
	us-gaap	Net Income Loss NetIncomeLoss	75382000
CY2021Q2	us-gaap	Amount Of Dilutive Securities Stock Options And Restrictive Stock Units AmountOfDilutiveSecuritiesStockOptionsAndRestrictiveStockUnits	-127000
CY2020Q2	us-gaap	Amount Of Dilutive Securities Stock Options And Restrictive Stock Units AmountOfDilutiveSecuritiesStockOptionsAndRestrictiveStockUnits	-127000
	us-gaap	Amount Of Dilutive Securities Stock Options And Restrictive Stock Units AmountOfDilutiveSecuritiesStockOptionsAndRestrictiveStockUnits	-263000
	us-gaap	Amount Of Dilutive Securities Stock Options And Restrictive Stock Units AmountOfDilutiveSecuritiesStockOptionsAndRestrictiveStockUnits	-264000
CY2021Q2	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	47817000
CY2020Q2	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	35121000
	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	100531000
	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	75118000
CY2021Q2	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	54007000
CY2020Q2	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	52487000
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	53927000
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	52262000
CY2021Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.89
CY2020Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.67
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.86
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.44
CY2021Q2	us-gaap	Net Income Loss NetIncomeLoss	47944000
CY2020Q2	us-gaap	Net Income Loss NetIncomeLoss	35248000
	us-gaap	Net Income Loss NetIncomeLoss	100794000
	us-gaap	Net Income Loss NetIncomeLoss	75382000
CY2021Q2	us-gaap	Amount Of Dilutive Securities Stock Options And Restrictive Stock Units AmountOfDilutiveSecuritiesStockOptionsAndRestrictiveStockUnits	-127000
CY2020Q2	us-gaap	Amount Of Dilutive Securities Stock Options And Restrictive Stock Units AmountOfDilutiveSecuritiesStockOptionsAndRestrictiveStockUnits	-127000
	us-gaap	Amount Of Dilutive Securities Stock Options And Restrictive Stock Units AmountOfDilutiveSecuritiesStockOptionsAndRestrictiveStockUnits	-263000
	us-gaap	Amount Of Dilutive Securities Stock Options And Restrictive Stock Units AmountOfDilutiveSecuritiesStockOptionsAndRestrictiveStockUnits	-264000
CY2021Q2	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	47817000
CY2020Q2	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	35121000
	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	100531000
	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	75118000
CY2021Q2	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	54007000
CY2020Q2	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	52487000
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	53927000
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	52262000
CY2021Q2	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	462000
CY2020Q2	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	339000
	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	455000
	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	372000
CY2021Q2	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	54469000
CY2020Q2	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	52826000
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	54382000
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	52634000
CY2021Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.88
CY2021Q2	us-gaap	Derivative Fair Value Of Derivative Liability DerivativeFairValueOfDerivativeLiability	7000
CY2020Q4	us-gaap	Derivative Fair Value Of Derivative Asset DerivativeFairValueOfDerivativeAsset	1588000
CY2020Q4	us-gaap	Derivative Fair Value Of Derivative Liability DerivativeFairValueOfDerivativeLiability	1074000
CY2020Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.66
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.85
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.43
CY2019Q4	us-gaap	Stock Repurchase Program Number Of Shares Authorized To Be Repurchased StockRepurchaseProgramNumberOfSharesAuthorizedToBeRepurchased	2600000
CY2020Q4	us-gaap	Stock Repurchase Program Number Of Shares Authorized To Be Repurchased StockRepurchaseProgramNumberOfSharesAuthorizedToBeRepurchased	2680000
	us-gaap	Treasury Stock Shares Acquired TreasuryStockSharesAcquired	0
	us-gaap	Treasury Stock Shares Acquired TreasuryStockSharesAcquired	0
CY2021Q2	us-gaap	Fair Value Disclosure Offbalance Sheet Risks Face Amount Liability FairValueDisclosureOffbalanceSheetRisksFaceAmountLiability	1235186000
CY2020Q4	us-gaap	Fair Value Disclosure Offbalance Sheet Risks Face Amount Liability FairValueDisclosureOffbalanceSheetRisksFaceAmountLiability	1352781000
CY2020	us-gaap	Litigation Settlement Expense LitigationSettlementExpense	3000000.0
CY2021Q2	us-gaap	Derivative Fair Value Of Derivative Asset DerivativeFairValueOfDerivativeAsset	533000
CY2021Q2	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	92105000
CY2021Q2	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	-4338000
CY2021Q2	us-gaap	Noninterest Income NoninterestIncome	59460000
CY2021Q2	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	3246000
CY2021Q2	us-gaap	Business Combination Acquisition Related Costs BusinessCombinationAcquisitionRelatedCosts	4000
CY2021Q2	us-gaap	Other Cost And Expense Operating OtherCostAndExpenseOperating	90293000
CY2021Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	62360000
CY2021Q2	us-gaap	Assets Assets	14801287000
CY2021Q2	us-gaap	Goodwill Goodwill	794892000
CY2021Q2	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	47780000
CY2020Q2	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	91951000
CY2020Q2	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	9774000
CY2020Q2	us-gaap	Noninterest Income NoninterestIncome	52938000
CY2020Q2	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	3524000
CY2020Q2	us-gaap	Business Combination Acquisition Related Costs BusinessCombinationAcquisitionRelatedCosts	3372000
CY2020Q2	us-gaap	Other Cost And Expense Operating OtherCostAndExpenseOperating	84007000
CY2020Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	44212000
CY2020Q2	us-gaap	Assets Assets	13444217000
CY2020Q2	us-gaap	Goodwill Goodwill	792715000
CY2020Q2	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	60046000
	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	186059000
	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	-10057000
	us-gaap	Noninterest Income NoninterestIncome	117991000
	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	6597000
	us-gaap	Business Combination Acquisition Related Costs BusinessCombinationAcquisitionRelatedCosts	31000
	us-gaap	Other Cost And Expense Operating OtherCostAndExpenseOperating	180161000
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	127318000
	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	182005000
	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	15368000
	us-gaap	Noninterest Income NoninterestIncome	111560000
	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	7191000
	us-gaap	Business Combination Acquisition Related Costs BusinessCombinationAcquisitionRelatedCosts	3741000
	us-gaap	Other Cost And Expense Operating OtherCostAndExpenseOperating	173634000
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	93631000

Files In Submission

Name	View Source	Status
0001104659-21-102085-index-headers.html	Edgar Link	pending
0001104659-21-102085-index.html	Edgar Link	pending
0001104659-21-102085.txt	Edgar Link	pending
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cbu-20210630.xsd	Edgar Link	pending
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$CBU
Community Financial System Inc Stock $cbu

2021 Q2 Form 10-Q Financial Statement

#000110465921102085 Filed on August 09, 2021

Income Statement

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$CBU Community Financial System Inc Stock $cbu

2021 Q2 Form 10-Q Financial Statement

#000110465921102085 Filed on August 09, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$CBU
Community Financial System Inc Stock $cbu