New Accounting Standards	12 Months Ended
Dec. 31, 2017
Accounting Changes and Error Corrections [Abstract]
New Accounting Standards	NEW ACCOUNTING STANDARDS The following paragraphs summarize accounting pronouncements issued by the Financial Accounting Standards Board (FASB) that we recently adopted or will be adopting in the future. Reporting Comprehensive Income Accounting Standards Update (ASU or Update) 2018-02, Income Statement - Reporting Comprehensive Income (Topic 220): Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income, allows for the reclassification from other comprehensive income to retained earnings for stranded tax effects resulting from the enacted tax bill H.R.1, commonly referred to as the Tax Cuts and Jobs Act (the TCJA). The Update also allows an accounting policy election to reclassify other stranded tax effects that relate to the TCJA but not directly related to the change in federal tax rate. This Update is effective in the first quarter of 2019. Early adoption is permitted for reporting periods for which financial statements have not yet been issued. We adopted this Update in the fourth quarter of 2017 by retrospective application. Upon adoption, the Corporation made a policy election to reclassify stranded tax effects of approximately $14.7 million from AOCI to retained earnings using the specific identification method. Stock-Based Compensation ASU 2017-09, Compensation - Stock Compensation (Topic 718): Scope of Modification Accounting, provides guidance about which changes to the terms and conditions of a share-based payment award requires the application of modification accounting. The Update is effective in the first quarter of 2018. Early adoption is permitted. This Update was adopted in the third quarter of 2017 by prospective application to awards modified on or after the adoption date. This Update did not have a material effect on our consolidated financial statements. ASU 2016-09, Compensation—Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting, simplifies several aspects of the accounting for share-based payment transactions, including the income tax consequences, classification of awards as either equity or liabilities and classification on the statement of cash flows. The Update was adopted in the first quarter of 2017 by an application method determined by the type of transaction impacted by the adoption. This Update did not have a material effect on our consolidated financial statements. Securities ASU 2017-08, Receivables-Nonrefundable Fees and Other Costs (Subtopic 310-20): Premium Amortization on Purchased Callable Debt Securities which shortens the amortization period for the premium on certain purchased callable securities to the earliest call date. The accounting for purchased callable debt securities held at a discount does not change. The Update is effective in the first quarter of 2019. Early adoption is permitted. The Update is to be applied using a modified retrospective transition method and is not expected to have a material effect on our consolidated financial statements. Retirement Benefits ASU 2017-07, Compensation—Retirement Benefits (Topic 715): Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost, requires that an employer disaggregate the service cost component from the other components of net benefit cost. The amendments also provide explicit guidance on how to present the service cost component and the other components of net benefit cost in the income statement and allows only the service cost component of net benefit cost to be eligible for capitalization. The Update is effective the first quarter of 2018. Early adoption is permitted. The Update is to be applied using a retrospective transition method to adopt the requirement for separate presentation in the income statement of service costs and other components and a prospective transition method to adopt the requirement to limit the capitalization of benefit costs to the service cost component. This Update is not expected to have a material effect on our consolidated financial statements. Goodwill ASU 2017-04, Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment, eliminates the requirement of Step 2 in the current guidance to calculate the implied fair value of goodwill to measure a goodwill impairment charge. Instead, entities will record an impairment charge based on the excess of a reporting unit’s carrying amount over its fair value in Step 1 of the current guidance. The Update is effective the first quarter of 2020. Early adoption is permitted for annual or interim goodwill impairment tests with a measurement date after January 1, 2017. We adopted this Update in the first quarter of 2017 and it did not have a material effect on our consolidated financial statements. Business Combinations ASU 2017-01, Business Combinations (Topic 850): Clarifying the Definition of a Business, clarifies the definition of a business with the objective of providing guidance to assist in the evaluation of whether transactions should be accounted for as acquisitions (disposals) of assets or businesses. The Update is effective for the first quarter of 2018. Early adoption is permitted for transactions that occurred before the issuance date or effective date of the Update if the transactions were not reported in financial statements that have been issued or made available for issuance. We adopted this Update in the first quarter of 2017. This Update is applied prospectively and did not have a material effect on our consolidated financial statements. Statement of Cash Flows ASU 2016-15, Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments (a consensus of the Emerging Issues Task Force), adds or clarifies guidance on eight cash flow issues. The Update is effective the first quarter of 2018. This Update will be applied retrospectively to all periods presented. Early adoption is permitted. This Update is not expected to have a material effect on our consolidated financial statements. Credit Losses ASU 2016-13, Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments, replaces the current incurred loss impairment methodology with a methodology that reflects current expected credit losses (commonly referred to as “CECL”) for most financial assets measured at amortized cost and certain other instruments, including loans, held-to-maturity debt securities, net investments in leases and off-balance sheet credit exposures. CECL requires loss estimates for the remaining life of the financial asset at the time the asset is originated or acquired, considering historical experience, current conditions and reasonable and supportable forecasts. In addition, the Update will require the use of a modified available-for-sale debt security impairment model and eliminate the current accounting for purchased credit impaired loans and debt securities. The Update is effective the first quarter of 2020 under a cumulative-effect adjustment to retained earnings. Early adoption is permitted for fiscal years beginning after December 15, 2018. The CECL model is a significant change from existing GAAP and may result in a material change to the Corporation’s accounting for financial instruments. We are reviewing our business processes, information systems and controls to support recognition and disclosures under this Update. This review includes an assessment of our existing credit models and the financial statement disclosure requirements. The impact of this Update will be dependent on the portfolio composition, credit quality and economic conditions at the time of adoption. Revenue Recognition ASU 2014-09, Revenue from Contracts with Customers (Topic 606), modifies the guidance used to recognize revenue from contracts with customers for transfers of goods and services and transfers of nonfinancial assets, unless those contracts are within the scope of other guidance. The guidance also requires new qualitative and quantitative disclosures about contract balances and performance obligations. We will adopt ASU 2014-09 in the first quarter of 2018 under the modified retrospective method where the cumulative effect is recognized at the date of initial application. Based on our evaluation under the current guidance, we estimate that substantially all of our interest income and non-interest income will not be impacted by the adoption of this ASU because either the revenue from those contracts with customers is covered by other guidance in U.S. GAAP or the revenue recognition outcomes anticipated with the adoption of this ASU will likely be similar to our current revenue recognition practices. In addition, we reviewed, and where necessary, enhanced our business processes, systems and controls to support recognition and disclosures under the new standard. The adoption of this Update is not expected to have a material effect on our consolidated financial statements. Investments ASU 2016-07, Investments—Equity Method and Joint Ventures (Topic 323): Simplifying the Transition to the Equity Method of Accounting, eliminates the requirement for an investor to retrospectively apply the equity method when an investment that it had accounted for by another method qualifies for use of the equity method. The Update was adopted in the first quarter of 2017 by prospective application. This Update did not have a material effect on our consolidated financial statements. Derivative and Hedging Activities ASU 2017-12, Derivatives and Hedging (Topic 815): Targeted Improvements to Accounting for Hedging Activities, improves the financial reporting of hedging to better align with the entity’s risk management activities. In addition, this Update makes certain targeted improvements to simplify the application of the current hedge accounting guidance. The Update is effective in the first quarter of 2019 by modified retrospective method. The presentation and disclosure guidance are applied prospectively. Early adoption is permitted. We are currently assessing the potential impact to our consolidated financial statements. ASU 2016-06, Derivatives and Hedging (Topic 815): Contingent Put and Call Options in Debt Instruments (a consensus of the Emerging Issues Task Force), provides clarification that determination of whether an embedded contingent put or call option in a financial instrument is clearly and closely related to the debt host requires only an analysis of the four-step decision sequence described in ASC 815-15-25-42. The Update was adopted in the first quarter of 2017 by modified retrospective application. This Update did not have a material effect on our consolidated financial statements. ASU 2016-05, Derivatives and Hedging (Topic 815): Effect of Derivative Contract Novations on Existing Hedge Accounting Relationships (a consensus of the Emerging Issues Task Force), clarifies that a change in counterparty to a derivative instrument that has been designated as a hedging instrument under Topic 815 does not, in and of itself, require dedesignation of that hedging relationship provided all other hedge accounting criteria continue to be met. The Update was adopted in the first quarter of 2017 by prospective application. This Update did not have a material effect on our consolidated financial statements. Extinguishments of Liabilities ASU 2016-04, Liabilities—Extinguishments of Liabilities (Subtopic 405-20): Recognition of Breakage for Certain Prepaid Stored-Value Products (a consensus of the Emerging Issues Task Force), requires entities that sell prepaid stored-value products redeemable for goods, services or cash at third-party merchants to recognize breakage. The Update is effective in the first quarter of 2018 with either the modified retrospective method by means of a cumulative-effect adjustment to retained earnings or retrospective application. Early adoption is permitted. This Update is not expected to have a material effect on our consolidated financial statements. Leases ASU 2016-02, Leases (Topic 842), requires lessees to put most leases on their balance sheets but recognize expenses in the income statement similar to current accounting. In addition, the Update changes the guidance for sale-leaseback transactions, initial direct costs and lease executory costs for most entities. All entities will classify leases to determine how to recognize lease related revenue and expense. The Update is effective in the first quarter of 2019 with modified retrospective application including a number of optional practical expedients. Early adoption is permitted. We are currently assessing the potential impact to our consolidated financial statements. Financial Instruments – Recognition and Measurement ASU 2016-01, Financial Instruments—Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities, amends the presentation and accounting for certain financial instruments, including liabilities measured at fair value under the fair value option, and equity investments. The guidance also updates fair value presentation and disclosure requirements for financial instruments measured at amortized cost. The Update is effective in the first quarter of 2018 with a cumulative-effect adjustment as of the beginning of the fiscal year of adoption. Early adoption is prohibited except for the provision requiring the recognition of changes in fair value related to changes in an entity’s own credit risk in other comprehensive income for financial liabilities measured using the fair value option. This Update is not expected to have a material effect on our consolidated financial statements.

NEW ACCOUNTING STANDARDS

The following paragraphs summarize accounting pronouncements issued by the Financial Accounting Standards Board (FASB) that we recently adopted or will be adopting in the future.

Reporting Comprehensive Income

Accounting Standards Update (ASU or Update) 2018-02, Income Statement - Reporting Comprehensive Income (Topic 220): Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income, allows for the reclassification from other comprehensive income to retained earnings for stranded tax effects resulting from the enacted tax bill H.R.1, commonly referred to as the Tax Cuts and Jobs Act (the TCJA). The Update also allows an accounting policy election to reclassify other stranded tax effects that relate to the TCJA but not directly related to the change in federal tax rate. This Update is effective in the first quarter of 2019. Early adoption is permitted for reporting periods for which financial statements have not yet been issued. We adopted this Update in the fourth quarter of 2017 by retrospective application. Upon adoption, the Corporation made a policy election to reclassify stranded tax effects of approximately $14.7 million from AOCI to retained earnings using the specific identification method.

Stock-Based Compensation

ASU 2017-09, Compensation - Stock Compensation (Topic 718): Scope of Modification Accounting, provides guidance about which changes to the terms and conditions of a share-based payment award requires the application of modification accounting. The Update is effective in the first quarter of 2018. Early adoption is permitted. This Update was adopted in the third quarter of 2017 by prospective application to awards modified on or after the adoption date. This Update did not have a material effect on our consolidated financial statements.

ASU 2016-09, Compensation—Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting, simplifies several aspects of the accounting for share-based payment transactions, including the income tax consequences, classification of awards as either equity or liabilities and classification on the statement of cash flows. The Update was adopted in the first quarter of 2017 by an application method determined by the type of transaction impacted by the adoption. This Update did not have a material effect on our consolidated financial statements.

Securities

ASU 2017-08, Receivables-Nonrefundable Fees and Other Costs (Subtopic 310-20): Premium Amortization on Purchased Callable Debt Securities which shortens the amortization period for the premium on certain purchased callable securities to the earliest call date. The accounting for purchased callable debt securities held at a discount does not change. The Update is effective in the first quarter of 2019. Early adoption is permitted. The Update is to be applied using a modified retrospective transition method and is not expected to have a material effect on our consolidated financial statements.

Retirement Benefits

ASU 2017-07, Compensation—Retirement Benefits (Topic 715): Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost, requires that an employer disaggregate the service cost component from the other components of net benefit cost. The amendments also provide explicit guidance on how to present the service cost component and the other components of net benefit cost in the income statement and allows only the service cost component of net benefit cost to be eligible for capitalization. The Update is effective the first quarter of 2018. Early adoption is permitted. The Update is to be applied using a retrospective transition method to adopt the requirement for separate presentation in the income statement of service costs and other components and a prospective transition method to adopt the requirement to limit the capitalization of benefit costs to the service cost component. This Update is not expected to have a material effect on our consolidated financial statements.

Goodwill

ASU 2017-04, Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment, eliminates the requirement of Step 2 in the current guidance to calculate the implied fair value of goodwill to measure a goodwill impairment charge. Instead, entities will record an impairment charge based on the excess of a reporting unit’s carrying amount over its fair value in Step 1 of the current guidance. The Update is effective the first quarter of 2020. Early adoption is permitted for annual or interim goodwill impairment tests with a measurement date after January 1, 2017. We adopted this Update in the first quarter of 2017 and it did not have a material effect on our consolidated financial statements.

Business Combinations

ASU 2017-01, Business Combinations (Topic 850): Clarifying the Definition of a Business, clarifies the definition of a business with the objective of providing guidance to assist in the evaluation of whether transactions should be accounted for as acquisitions (disposals) of assets or businesses. The Update is effective for the first quarter of 2018. Early adoption is permitted for transactions that occurred before the issuance date or effective date of the Update if the transactions were not reported in financial statements that have been issued or made available for issuance. We adopted this Update in the first quarter of 2017. This Update is applied prospectively and did not have a material effect on our consolidated financial statements.

Statement of Cash Flows

ASU 2016-15, Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments (a consensus of the Emerging Issues Task Force), adds or clarifies guidance on eight cash flow issues. The Update is effective the first quarter of 2018. This Update will be applied retrospectively to all periods presented. Early adoption is permitted. This Update is not expected to have a material effect on our consolidated financial statements.

Credit Losses

ASU 2016-13, Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments, replaces the current incurred loss impairment methodology with a methodology that reflects current expected credit losses (commonly referred to as “CECL”) for most financial assets measured at amortized cost and certain other instruments, including loans, held-to-maturity debt securities, net investments in leases and off-balance sheet credit exposures. CECL requires loss estimates for the remaining life of the financial asset at the time the asset is originated or acquired, considering historical experience, current conditions and reasonable and supportable forecasts. In addition, the Update will require the use of a modified available-for-sale debt security impairment model and eliminate the current accounting for purchased credit impaired loans and debt securities. The Update is effective the first quarter of 2020 under a cumulative-effect adjustment to retained earnings. Early adoption is permitted for fiscal years beginning after December 15, 2018. The CECL model is a significant change from existing GAAP and may result in a material change to the Corporation’s accounting for financial instruments. We are reviewing our business processes, information systems and controls to support recognition and disclosures under this Update. This review includes an assessment of our existing credit models and the financial statement disclosure requirements. The impact of this Update will be dependent on the portfolio composition, credit quality and economic conditions at the time of adoption.

Revenue Recognition

ASU 2014-09, Revenue from Contracts with Customers (Topic 606), modifies the guidance used to recognize revenue from contracts with customers for transfers of goods and services and transfers of nonfinancial assets, unless those contracts are within the scope of other guidance. The guidance also requires new qualitative and quantitative disclosures about contract balances and performance obligations.

We will adopt ASU 2014-09 in the first quarter of 2018 under the modified retrospective method where the cumulative effect is recognized at the date of initial application. Based on our evaluation under the current guidance, we estimate that substantially all of our interest income and non-interest income will not be impacted by the adoption of this ASU because either the revenue from those contracts with customers is covered by other guidance in U.S. GAAP or the revenue recognition outcomes anticipated with the adoption of this ASU will likely be similar to our current revenue recognition practices. In addition, we reviewed, and where necessary, enhanced our business processes, systems and controls to support recognition and disclosures under the new standard. The adoption of this Update is not expected to have a material effect on our consolidated financial statements.

Investments

ASU 2016-07, Investments—Equity Method and Joint Ventures (Topic 323): Simplifying the Transition to the Equity Method of Accounting, eliminates the requirement for an investor to retrospectively apply the equity method when an investment that it had accounted for by another method qualifies for use of the equity method. The Update was adopted in the first quarter of 2017 by prospective application. This Update did not have a material effect on our consolidated financial statements.

Derivative and Hedging Activities

ASU 2017-12, Derivatives and Hedging (Topic 815): Targeted Improvements to Accounting for Hedging Activities, improves the financial reporting of hedging to better align with the entity’s risk management activities. In addition, this Update makes certain targeted improvements to simplify the application of the current hedge accounting guidance. The Update is effective in the first quarter of 2019 by modified retrospective method. The presentation and disclosure guidance are applied prospectively. Early adoption is permitted. We are currently assessing the potential impact to our consolidated financial statements.

ASU 2016-06, Derivatives and Hedging (Topic 815): Contingent Put and Call Options in Debt Instruments (a consensus of the Emerging Issues Task Force), provides clarification that determination of whether an embedded contingent put or call option in a financial instrument is clearly and closely related to the debt host requires only an analysis of the four-step decision sequence described in ASC 815-15-25-42. The Update was adopted in the first quarter of 2017 by modified retrospective application. This Update did not have a material effect on our consolidated financial statements.

ASU 2016-05, Derivatives and Hedging (Topic 815): Effect of Derivative Contract Novations on Existing Hedge Accounting Relationships (a consensus of the Emerging Issues Task Force), clarifies that a change in counterparty to a derivative instrument that has been designated as a hedging instrument under Topic 815 does not, in and of itself, require dedesignation of that hedging relationship provided all other hedge accounting criteria continue to be met. The Update was adopted in the first quarter of 2017 by prospective application. This Update did not have a material effect on our consolidated financial statements.

Extinguishments of Liabilities

ASU 2016-04, Liabilities—Extinguishments of Liabilities (Subtopic 405-20): Recognition of Breakage for Certain Prepaid Stored-Value Products (a consensus of the Emerging Issues Task Force), requires entities that sell prepaid stored-value products redeemable for goods, services or cash at third-party merchants to recognize breakage. The Update is effective in the first quarter of 2018 with either the modified retrospective method by means of a cumulative-effect adjustment to retained earnings or retrospective application. Early adoption is permitted. This Update is not expected to have a material effect on our consolidated financial statements.

Leases

ASU 2016-02, Leases (Topic 842), requires lessees to put most leases on their balance sheets but recognize expenses in the income statement similar to current accounting. In addition, the Update changes the guidance for sale-leaseback transactions, initial direct costs and lease executory costs for most entities. All entities will classify leases to determine how to recognize lease related revenue and expense. The Update is effective in the first quarter of 2019 with modified retrospective application including a number of optional practical expedients. Early adoption is permitted. We are currently assessing the potential impact to our consolidated financial statements.

Financial Instruments – Recognition and Measurement

ASU 2016-01, Financial Instruments—Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities, amends the presentation and accounting for certain financial instruments, including liabilities measured at fair value under the fair value option, and equity investments. The guidance also updates fair value presentation and disclosure requirements for financial instruments measured at amortized cost. The Update is effective in the first quarter of 2018 with a cumulative-effect adjustment as of the beginning of the fiscal year of adoption. Early adoption is prohibited except for the provision requiring the recognition of changes in fair value related to changes in an entity’s own credit risk in other comprehensive income for financial liabilities measured using the fair value option. This Update is not expected to have a material effect on our consolidated financial statements.