CONSOLIDATED STATEMENTS OF INCOME AND COMPREHENSIVE INCOME (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
INTEREST AND DIVIDEND INCOME:
Loans, including related fees	$ 87,530	$ 91,242	$ 99,196
Securities:
Taxable	17,015us-gaap_InterestIncomeSecuritiesTaxable	16,157us-gaap_InterestIncomeSecuritiesTaxable	13,542us-gaap_InterestIncomeSecuritiesTaxable
Tax-exempt	7,084	7,046	7,246
Other	1,729us-gaap_OtherInterestAndDividendIncome	1,776us-gaap_OtherInterestAndDividendIncome	2,321us-gaap_OtherInterestAndDividendIncome
TOTAL INTEREST AND DIVIDEND INCOME	113,358	116,221	122,305
INTEREST EXPENSE:
Deposits	4,624us-gaap_InterestExpenseDeposits	5,886us-gaap_InterestExpenseDeposits	8,520us-gaap_InterestExpenseDeposits
Short-term borrowings	99	78	140
Other borrowings	803us-gaap_InterestExpenseOther	2,997us-gaap_InterestExpenseOther	4,733us-gaap_InterestExpenseOther
TOTAL INTEREST EXPENSE	5,526us-gaap_InterestExpense	8,961us-gaap_InterestExpense	13,393us-gaap_InterestExpense
NET INTEREST INCOME	107,832us-gaap_InterestIncomeExpenseNet	107,260us-gaap_InterestIncomeExpenseNet	108,912us-gaap_InterestIncomeExpenseNet
Net Provision for loan losses	5,072us-gaap_ProvisionForLoanAndLeaseLosses	7,860us-gaap_ProvisionForLoanAndLeaseLosses	8,773us-gaap_ProvisionForLoanAndLeaseLosses
NET INTEREST INCOME AFTER PROVISION FOR LOAN LOSSES	102,760	99,400	100,139
NON-INTEREST INCOME:
Trust and financial services	5,860
Service charges and fees on deposit accounts			9,742
Other service charges and fees	11,697us-gaap_FeesAndCommissionsOther	11,081us-gaap_FeesAndCommissionsOther	9,710us-gaap_FeesAndCommissionsOther
Securities gain (loss), net	(3)us-gaap_GainLossOnSaleOfSecuritiesNet	423us-gaap_GainLossOnSaleOfSecuritiesNet	886us-gaap_GainLossOnSaleOfSecuritiesNet
Other-than-temporary loss
Total impairment loss	0us-gaap_ImpairmentOfInvestments	0us-gaap_ImpairmentOfInvestments	(11)us-gaap_ImpairmentOfInvestments
Loss recognized in other comprehensive income	0	0	0
Net impairment loss recognized in earnings	0us-gaap_AssetImpairmentCharges	0us-gaap_AssetImpairmentCharges	(11)us-gaap_AssetImpairmentCharges
Insurance commissions	7,646us-gaap_InsuranceCommissionsAndFees	7,750us-gaap_InsuranceCommissionsAndFees	7,422us-gaap_InsuranceCommissionsAndFees
Gain on sale of mortgage loans	1,849us-gaap_GainLossOnSaleOfMortgageLoans	3,052us-gaap_GainLossOnSaleOfMortgageLoans	4,590us-gaap_GainLossOnSaleOfMortgageLoans
Other	2,964	1,952	1,404
TOTAL NON-INTEREST INCOME	40,785us-gaap_NoninterestIncome	40,455us-gaap_NoninterestIncome	39,547us-gaap_NoninterestIncome
NON-INTEREST EXPENSES:
Salaries and employee benefits	55,936	55,097	56,211
Occupancy expense	7,218us-gaap_OccupancyNet	6,102us-gaap_OccupancyNet	5,746us-gaap_OccupancyNet
Equipment expense	7,269us-gaap_EquipmentExpense	6,348us-gaap_EquipmentExpense	5,489us-gaap_EquipmentExpense
Federal Deposit Insurance	1,931	2,052	1,949
Other	23,230us-gaap_OtherNoninterestExpense	24,955us-gaap_OtherNoninterestExpense	23,661us-gaap_OtherNoninterestExpense
TOTAL NON-INTEREST EXPENSE	95,584us-gaap_NoninterestExpense	94,554us-gaap_NoninterestExpense	93,056us-gaap_NoninterestExpense
INCOME BEFORE INCOME TAXES	47,961	45,301	46,630
Provision for income taxes	14,189us-gaap_IncomeTaxExpenseBenefit	13,767us-gaap_IncomeTaxExpenseBenefit	13,818us-gaap_IncomeTaxExpenseBenefit
NET INCOME	33,772us-gaap_NetIncomeLoss	31,534us-gaap_NetIncomeLoss	32,812us-gaap_NetIncomeLoss
OTHER COMPREHENSIVE INCOME
Change in unrealized gains/losses on securities, net of reclassifications and taxes	13,913	(17,066)	691
Change in funded status of post-retirement benefits, net of taxes	(14,473)	10,569	2,331
COMPREHENSIVE INCOME	33,212us-gaap_ComprehensiveIncomeNetOfTax
EARNINGS PER SHARE:
BASIC AND DILUTED (in dollars per share)	$ 2.55us-gaap_EarningsPerShareBasicAndDiluted	$ 2.37us-gaap_EarningsPerShareBasicAndDiluted	$ 2.48us-gaap_EarningsPerShareBasicAndDiluted
Weighted average number of shares outstanding (in shares)	13,226	13,310	13,240
Trust and Financial Services		6,035thff_TrustAndFinancialServices	5,804thff_TrustAndFinancialServices
Fees and Commissions Depositor Accounts Excluding Atm Fees	$ 10,772	$ 10,162

Includes amounts charged depositors for: (1) maintenance of their accounts (maintenance charges); (2) failure to maintain specified minimum balances on account; (3) exceeding the number of checks or transactions allowed to be processed in a given period; (4) checks drawn on no minimum balance deposit accounts; (5) withdrawals from nontransaction deposit accounts; (6) closing savings accounts before a specified minimum period of time has elapsed; (7) accounts which have remained inactive for extended periods of time or which have become dormant; (8) checks drawn against insufficient funds that the bank assesses regardless of whether it decides to pay, return or hold the check; (9) issuing stop payment orders; (10) certifying checks; and (11) accumulating or disbursing funds deposited in IRAs or Keogh Plan accounts when not handled by the bank's trust department. This item does not include penalties assessed on the early withdrawal of time deposits.

No definition available.