Revenue from Contracts with Customers (Policies)	3 Months Ended
Mar. 31, 2018
Revenue from Contracts with Customers [Abstract]
Revenue Recognition	Effective January 1, 2018, the Company adopted FASB ASU 2014-09, Revenue from Contracts with Customers (ASC Topic 606) ("ASC 606" and "ASU 2014-09"), and all subsequent ASUs that modified ASC 606. The implementation of ASC 606 did not have a material impact on the measurement or recognition of revenue; as such, a cumulative effect adjustment to opening retained earnings was not deemed necessary. Results for reporting periods beginning after January 1, 2018 are presented under ASC 606, while prior period amounts were not adjusted and continue to be reported in accordance with our historic accounting under ASC 605. ASC 606 does not apply to revenue associated with financial instruments, including revenue from loans and securities and certain noninterest income streams such as fees associated with mortgage servicing rights, financial guarantees, derivatives, and certain credit card fees are also not in scope. ASC 606 is applicable to noninterest revenue streams such as trust and asset management income, deposit related fees and annuity and insurance commissions; however, the recognition of these revenue streams did not change significantly upon adoption of ASC 606. Insurance and Other Financial Services Revenue Insurance and other financial services revenue primarily consists of commissions received on insurance and brokered investment product sales. The Company acts as an intermediary between the Company's customer and the insurance carrier. The Company's performance obligation is generally satisfied upon the issuance of the annuity policy. Shortly after the policy is issued, the carrier remits the commission payment to the Company, and the Company recognizes the revenue. The Company does not earn a significant amount of trailing commission fees on insurance or brokered investment product sales. The majority of the trailing commission fees are calculated based on a percentage of market value of a period end and revenue is recognized when an investment product's market value can be determined. Service Charges on Deposit Accounts Service charges on deposit accounts consist of overdraft fees, monthly service fees, check orders, and other deposit account related fees. Overdraft, monthly service, check orders and other deposit account related fees are transactional based, and therefore, the Company's performance obligation is satisfied, and related revenue recognized, at a point in time. Payment for service charges on deposit accounts is primarily received immediately or in the following month through a direct charge to customers' accounts. ATM and Debit Card Fees ATM fees are primarily generated when a Company cardholder uses a non-Company ATM or a non-Company cardholder uses a Company ATM. Debit card income is primarily comprised of interchange fees earned whenever the Company's debit cards are processed through card payment networks. The Company's performance obligations for these revenue streams are satisfied, and related revenue recognized, when the services are rendered or upon completion. Payment is typically received immediately or in the following month. Retirement Plan Administration Fees Retirement plan administration fees are primarily generated for services related to the recordkeeping, administration and plan design solutions of defined benefit, defined contribution and revenue sharing plans. Revenue is recognized in arrears for services already provided in accordance with fees established in contracts with customers or based on rates agreed to with investment trade platforms based on ending investment balances held. The Company's performance obligation is satisfied, and related revenue recognized based on services completed or ending investment balances, for which receivables are recorded at the time of revenue recognition. Trust Trust and asset management income is primarily comprised of fees earned from the management and administration of trusts, pensions and other customer assets. The Company's performance obligation is generally satisfied with the resulting fees are recognized monthly, based upon services completed or the month-end market value of the assets under management and the applicable fee rate. Payment is generally received shortly after services are rendered or a few days after month end through a direct charge to customers' accounts. The Company does not earn performance-based incentives. Other Other noninterest income consists of other recurring revenue streams such as account and loan fees, interest rate swap fees, safety deposit box rental fees, and other miscellaneous revenue streams. These revenue streams are primarily transactional based and payment is received immediately or in the following month, and therefore, the Company's performance obligation is satisfied, and related revenue recognized, at a point in time.

Effective January 1, 2018, the Company adopted FASB ASU 2014-09, Revenue from Contracts with Customers (ASC Topic 606) ("ASC 606" and "ASU 2014-09"), and all subsequent ASUs that modified ASC 606. The implementation of ASC 606 did not have a material impact on the measurement or recognition of revenue; as such, a cumulative effect adjustment to opening retained earnings was not deemed necessary. Results for reporting periods beginning after January 1, 2018 are presented under ASC 606, while prior period amounts were not adjusted and continue to be reported in accordance with our historic accounting under ASC 605. ASC 606 does not apply to revenue associated with financial instruments, including revenue from loans and securities and certain noninterest income streams such as fees associated with mortgage servicing rights, financial guarantees, derivatives, and certain credit card fees are also not in scope. ASC 606 is applicable to noninterest revenue streams such as trust and asset management income, deposit related fees and annuity and insurance commissions; however, the recognition of these revenue streams did not change significantly upon adoption of ASC 606.

Insurance and Other Financial Services Revenue

Insurance and other financial services revenue primarily consists of commissions received on insurance and brokered investment product sales. The Company acts as an intermediary between the Company's customer and the insurance carrier. The Company's performance obligation is generally satisfied upon the issuance of the annuity policy. Shortly after the policy is issued, the carrier remits the commission payment to the Company, and the Company recognizes the revenue. The Company does not earn a significant amount of trailing commission fees on insurance or brokered investment product sales. The majority of the trailing commission fees are calculated based on a percentage of market value of a period end and revenue is recognized when an investment product's market value can be determined.

Service Charges on Deposit Accounts

Service charges on deposit accounts consist of overdraft fees, monthly service fees, check orders, and other deposit account related fees. Overdraft, monthly service, check orders and other deposit account related fees are transactional based, and therefore, the Company's performance obligation is satisfied, and related revenue recognized, at a point in time. Payment for service charges on deposit accounts is primarily received immediately or in the following month through a direct charge to customers' accounts.

ATM and Debit Card Fees

ATM fees are primarily generated when a Company cardholder uses a non-Company ATM or a non-Company cardholder uses a Company ATM. Debit card income is primarily comprised of interchange fees earned whenever the Company's debit cards are processed through card payment networks. The Company's performance obligations for these revenue streams are satisfied, and related revenue recognized, when the services are rendered or upon completion. Payment is typically received immediately or in the following month.

Retirement Plan Administration Fees

Retirement plan administration fees are primarily generated for services related to the recordkeeping, administration and plan design solutions of defined benefit, defined contribution and revenue sharing plans. Revenue is recognized in arrears for services already provided in accordance with fees established in contracts with customers or based on rates agreed to with investment trade platforms based on ending investment balances held. The Company's performance obligation is satisfied, and related revenue recognized based on services completed or ending investment balances, for which receivables are recorded at the time of revenue recognition.

Trust

Trust and asset management income is primarily comprised of fees earned from the management and administration of trusts, pensions and other customer assets. The Company's performance obligation is generally satisfied with the resulting fees are recognized monthly, based upon services completed or the month-end market value of the assets under management and the applicable fee rate. Payment is generally received shortly after services are rendered or a few days after month end through a direct charge to customers' accounts. The Company does not earn performance-based incentives.

Other

Other noninterest income consists of other recurring revenue streams such as account and loan fees, interest rate swap fees, safety deposit box rental fees, and other miscellaneous revenue streams. These revenue streams are primarily transactional based and payment is received immediately or in the following month, and therefore, the Company's performance obligation is satisfied, and related revenue recognized, at a point in time.