Loan and Lease Receivables, Impaired Loans and Leases and Allowance for Loan and Lease Losses (Policies)	12 Months Ended
Dec. 31, 2018
Receivables [Abstract]
Allowance for Loan and Lease Losses	The allowance for loan and lease losses is maintained at a level that management deems appropriate to absorb probable and estimable losses inherent in the loan and lease portfolios. The methodology applied for determining inherent losses stems from current risk characteristics of the loan and lease portfolio, an assessment of individual impaired loans and leases, actual loss experience and adverse situations that may affect the borrower’s ability to repay. The methodology also focuses on evaluation of several factors for each portfolio category, including but not limited to: management’s ongoing review and grading of the loan and lease portfolios, consideration of delinquency experience, changes in the size of the loan and lease portfolios, existing economic conditions, level of loans and leases subject to more frequent review by management, changes in underlying collateral, concentrations of loans to specific industries, and other qualitative and quantitative factors that could affect credit losses. Impaired and other loans and leases have risk characteristics that are unique to an individual borrower and the loss must be estimated on an individual basis. Loans and leases that are not individually reviewed and measured for impairment are aggregated and historical loss statistics are primarily used to determine the risk of loss. The measurement of the estimate of loss is reliant upon historical experience, information about the ability of the individual debtor to pay, and the appraisal of loan collateral in light of current economic conditions. An estimate of loss is an approximation of what portion of all amounts receivable, according to the contractual terms of that receivable, is deemed uncollectible. Determination of the allowance is inherently subjective because it requires estimation of amounts and timing of expected future cash flows on impaired loans and leases, estimation of losses on types of loans and leases based on historical losses, and consideration of current economic trends, both local and national. Based on management’s periodic review using all previously mentioned pertinent factors, a provision for loan and lease losses is charged to expense when it is determined an increase in the allowance for loan and lease losses is appropriate. A negative provision for loan and lease losses may be recognized if management determines a reduction in the level of allowance for loan and lease losses is appropriate. Loan and lease losses are charged against the allowance and recoveries are credited to the allowance. The allowance for loan and lease losses contains specific allowances established for expected losses on impaired loans and leases. Impaired loans and leases are defined as loans and leases for which, based on current information and events, it is probable that the Corporation will be unable to collect scheduled principal and interest payments according to the contractual terms of the loan or lease agreement. Loans and leases subject to impairment are defined as non-accrual and restructured loans and leases. Impaired loans and leases are evaluated on an individual basis to determine the amount of specific reserve or charge-off required, if any. The measurement value of impaired loans and leases is determined based on the present value of expected future cash flows discounted at the loan’s effective interest rate (the contractual interest rate adjusted for any net deferred loan fees or costs, premium or discount existing at the origination or acquisition of the loan), the market price of the loan or lease, or the fair value of the underlying collateral less costs to sell, if the loan or lease is collateral dependent. A loan or lease is collateral dependent if repayment is expected to be provided principally by the underlying collateral. A loan’s effective interest rate may change over the life of the loan based on subsequent changes in rates or indices, or may be fixed at the rate in effect at the date the loan was determined to be impaired. Subsequent to the initial impairment, any significant change in the amount or timing of an impaired loan or lease’s future cash flows will result in a reassessment of the valuation allowance to determine if an adjustment is necessary. Measurements based on observable market price or fair value of the collateral may change over time and require a reassessment of the allowance if there is a significant change in either measurement base. Any increase in the present value of expected future cash flows attributable to the passage of time is recorded as interest income accrued on the net carrying amount of the loan or lease at the effective interest rate used to discount the impaired loan or lease’s estimated future cash flows. Any change in present value attributable to changes in the amount or timing of expected future cash flows is recorded as loan loss expense in the same manner in which impairment was initially recognized or as a reduction of loan loss expense that otherwise would be reported. Where the level of loan or lease impairment is measured using observable market price or fair value of collateral, any decrease in the observable market price of an impaired loan or lease or fair value of the collateral of an impaired collateral-dependent loan or lease is recorded as loan loss expense in the same manner in which impairment was initially recognized. Any increase in the observable market value of the impaired loan or lease or fair value of the collateral of an impaired collateral-dependent loan or lease is recorded as a reduction in the amount of loan loss expense that otherwise would be reported. To determine the level and composition of the allowance for loan and lease losses, the Corporation categorizes the portfolio into segments with similar risk characteristics. First, the Corporation evaluates loans and leases for potential impairment classification. The Corporation analyzes each loan and lease determined to be impaired on an individual basis to determine a specific reserve based upon the estimated value of the underlying collateral for collateral-dependent loans, or alternatively, the present value of expected cash flows. The Corporation applies historical trends from established risk factors to each category of loans and leases that has not been individually evaluated for the purpose of establishing the general portion of the allowance.

The allowance for loan and lease losses is maintained at a level that management deems appropriate to absorb probable and estimable losses inherent in the loan and lease portfolios. The methodology applied for determining inherent losses stems from current risk characteristics of the loan and lease portfolio, an assessment of individual impaired loans and leases, actual loss experience and adverse situations that may affect the borrower’s ability to repay. The methodology also focuses on evaluation of several factors for each portfolio category, including but not limited to: management’s ongoing review and grading of the loan and lease portfolios, consideration of delinquency experience, changes in the size of the loan and lease portfolios, existing economic conditions, level of loans and leases subject to more frequent review by management, changes in underlying collateral, concentrations of loans to specific industries, and other qualitative and quantitative factors that could affect credit losses. Impaired and other loans and leases have risk characteristics that are unique to an individual borrower and the loss must be estimated on an individual basis. Loans and leases that are not individually reviewed and measured for impairment are aggregated and historical loss statistics are primarily used to determine the risk of loss.

The measurement of the estimate of loss is reliant upon historical experience, information about the ability of the individual debtor to pay, and the appraisal of loan collateral in light of current economic conditions. An estimate of loss is an approximation of what portion of all amounts receivable, according to the contractual terms of that receivable, is deemed uncollectible. Determination of the allowance is inherently subjective because it requires estimation of amounts and timing of expected future cash flows on impaired loans and leases, estimation of losses on types of loans and leases based on historical losses, and consideration of current economic trends, both local and national. Based on management’s periodic review using all previously mentioned pertinent factors, a provision for loan and lease losses is charged to expense when it is determined an increase in the allowance for loan and lease losses is appropriate. A negative provision for loan and lease losses may be recognized if management determines a reduction in the level of allowance for loan and lease losses is appropriate. Loan and lease losses are charged against the allowance and recoveries are credited to the allowance.

The allowance for loan and lease losses contains specific allowances established for expected losses on impaired loans and leases. Impaired loans and leases are defined as loans and leases for which, based on current information and events, it is probable that the Corporation will be unable to collect scheduled principal and interest payments according to the contractual terms of the loan or lease agreement. Loans and leases subject to impairment are defined as non-accrual and restructured loans and leases.

Impaired loans and leases are evaluated on an individual basis to determine the amount of specific reserve or charge-off required, if any. The measurement value of impaired loans and leases is determined based on the present value of expected future cash flows discounted at the loan’s effective interest rate (the contractual interest rate adjusted for any net deferred loan fees or costs, premium or discount existing at the origination or acquisition of the loan), the market price of the loan or lease, or the fair value of the underlying collateral less costs to sell, if the loan or lease is collateral dependent. A loan or lease is collateral dependent if repayment is expected to be provided principally by the underlying collateral. A loan’s effective interest rate may change over the life of the loan based on subsequent changes in rates or indices, or may be fixed at the rate in effect at the date the loan was determined to be impaired.

Subsequent to the initial impairment, any significant change in the amount or timing of an impaired loan or lease’s future cash flows will result in a reassessment of the valuation allowance to determine if an adjustment is necessary. Measurements based on observable market price or fair value of the collateral may change over time and require a reassessment of the allowance if there is a significant change in either measurement base. Any increase in the present value of expected future cash flows attributable to the passage of time is recorded as interest income accrued on the net carrying amount of the loan or lease at the effective interest rate used to discount the impaired loan or lease’s estimated future cash flows. Any change in present value attributable to changes in the amount or timing of expected future cash flows is recorded as loan loss expense in the same manner in which impairment was initially recognized or as a reduction of loan loss expense that otherwise would be reported. Where the level of loan or lease impairment is measured using observable market price or fair value of collateral, any decrease in the observable market price of an impaired loan or lease or fair value of the collateral of an impaired collateral-dependent loan or lease is recorded as loan loss expense in the same manner in which impairment was initially recognized. Any increase in the observable market value of the impaired loan or lease or fair value of the collateral of an impaired collateral-dependent loan or lease is recorded as a reduction in the amount of loan loss expense that otherwise would be reported.