Our accompanying Consolidated Financial Statements and these Notes to Consolidated Financial Statements include subsidiaries in which we have a controlling financial interest. We own and operate FNBPA, FNTC, First National Investment Services Company, LLC, FNBIA, FNIA, Bank Capital Services, LLC, and F.N.B. Capital Corporation, LLC, and include results for each of these entities in the accompanying Consolidated Financial Statements.

Companies in which we hold more than a 50% voting equity interest, or a controlling financial interest, or are a variable interest entity (VIE) in which we have the power to direct the activities of an entity that most significantly impact the entity’s economic performance and has an obligation to absorb losses or the right to receive benefits from the VIE which could potentially be significant to the VIE are consolidated. VIEs in which we do not hold the power to direct the activities of the entity that most significantly impact the entity’s economic performance or does not have an obligation to absorb losses or the right to receive benefits from the VIE which could potentially be significant to the VIE are not consolidated. Investments in companies that are not consolidated are accounted for using the equity method when we have the ability to exert significant influence. Investments in private investment partnerships that are accounted for under the equity method or the cost method are included in other assets and our proportional interest in the equity investments’ earnings are included in other non-interest income. Investment interests accounted for under the cost and equity methods are periodically evaluated for impairment.

The accompanying Consolidated Financial Statements include all adjustments that are necessary, in the opinion of management, to fairly reflect our financial position and results of operations in accordance with GAAP. All significant intercompany balances and transactions have been eliminated. Certain prior period amounts have been reclassified to conform to the current period presentation. Such reclassifications had no impact on our net income and stockholders’ equity. Events occurring subsequent to December 31, 2019 have been evaluated for potential recognition or disclosure in the Consolidated Financial Statements through the date of the filing of the Consolidated Financial Statements with the Securities and Exchange Commission.

Our accounting and reporting policies conform with GAAP. The preparation of financial statements in conformity with GAAP requires us to make estimates and assumptions that affect the amounts reported in the Consolidated Financial Statements and accompanying Notes to Consolidated Financial Statements. Actual results could materially differ from those estimates. Material estimates that are particularly susceptible to significant changes include the allowance for credit losses, accounting for loans acquired in a business combination, fair value of financial instruments, goodwill and other intangible assets, litigation, income taxes and deferred tax assets.

In determining the appropriate revenue recognition for our contracts with customers, we consider whether the contract has commercial substance and is approved by both parties with identifiable contractual rights, payment terms, and the collectability of consideration is probable. Generally, we satisfy our performance obligations upon the completion of services at the amount to which we have the right to invoice or charge under contracts with an original expected duration of one year or less. We apply this guidance on a portfolio basis to contracts with similar characteristics and for which we believe the results would not differ materially from applying this guidance to individual contracts.

Our services provided under contracts with customers are transferred at the point in time when the services are rendered. Generally, we do not defer incremental direct costs to obtain contracts with customers that would be amortized in one year or less under the practical expedient. These costs are recognized as expense, primarily salary and benefit expense, in the period incurred.

Deposit Services. We recognize revenue on deposit services based on published fees for services provided. Demand and savings deposit customers have the right to cancel their depository arrangements and withdraw their deposited funds at any time without prior notice. When services involve deposited funds that can be retrieved by customers without penalties, we consider the service contract term to be day-to-day, where each day represents the renewal of the contract. The contract does not extend beyond the services performed and revenue is recognized at the end of the contract term (daily) as the performance obligation is satisfied.

Revenue from deposit services fees are reduced where we have a history of waived or reduced fees by customer request or due to a customer service issue, by historical experience, or another acceptable method in the same period as the related revenues. Revenues from deposit services are reported in the Consolidated Statements of Income as service charges and in the Community Banking segment as non-interest income.

Wealth Management Services. Wealth advisory and trust services are provided on a month-to-month basis and invoiced as services are rendered. Fees are based on a fixed amount or a scale based on the level of services provided or assets under management. The customer has the right to terminate their services agreement at any time. We determine the value of services performed based on the fee schedule in effect at the time the services are performed. Revenues from wealth advisory and trust services are reported in the Consolidated Statements of Income as trust services and securities commissions and fees, and in the Wealth segment as non-interest income.

Insurance Services. Insurance services include full-service insurance brokerage services offering numerous lines of commercial and personal insurance through major carriers to businesses and individuals within our geographic markets. We recognize revenue on insurance contracts in effect based on contractually specified commission payments on premiums that are paid by the customer to the insurance carrier. Contracts are cancellable at any time and we have no performance obligation to the customers beyond the time the insurance is placed into effect. Revenues from insurance services are reported in the Consolidated Statements of Income as insurance commissions and fees, and in the Insurance segment as non-interest income.

Business combinations are accounted for by applying the acquisition method. Under the acquisition method, identifiable assets acquired and liabilities assumed, and any non-controlling interest in the acquiree at the acquisition date are measured at their fair values as of that date, and are recognized separately from goodwill. Results of operations of the acquired entities are included in the Consolidated Statements of Income from the date of acquisition.

If we intend to sell the debt security or it is more likely than not we will be required to sell the security before recovery of its amortized cost basis, OTTI must be recognized in earnings equal to the entire difference between the investments’ amortized cost basis and its fair value. If we do not intend to sell the debt security and it is not more likely than not that we will be required to sell the security before recovery of its amortized cost basis, OTTI must be separated into the amount representing credit loss and the amount related to all other market factors. The amount related to credit loss will be recognized in earnings. The amount related to other market factors will be recognized in OCI, net of tax.

We perform our OTTI evaluation process in a consistent and systematic manner and include an evaluation of all available evidence. This process considers factors such as length of time and anticipated recovery period of the impairment, recent events specific to the issuer and recent experience regarding principal and interest payments.

Securities sold under agreements to repurchase are accounted for as collateralized financing transactions and are recorded at the amounts at which the securities were sold plus accrued interest. Securities, generally U.S. government and federal agency securities, pledged as collateral under these financing arrangements cannot be sold or repledged by the secured party. The fair value of collateral either received from or provided to a third party is continually monitored and additional collateral is obtained or is requested to be returned to us as deemed appropriate.

From time to time, we may enter into derivative transactions principally to protect against the risk of adverse price or interest rate movements on the value of certain assets and liabilities and on future cash flows. Foreign exchange derivatives are entered into to accommodate the needs of customers. All derivative instruments are carried at fair value on the Consolidated Balance Sheets as either an asset or liability. Accounting for the changes in fair value of a derivative is dependent upon whether it has been designated in a formal, qualifying hedging relationship. For derivatives in qualifying hedging relationships, we formally document all relationships between hedging instruments and hedged items, as well as our risk management objective and strategy for undertaking each hedge transaction. Cash flows from hedging activities are classified in the same category as the items hedged.

Beginning in the first quarter of 2019, we adopted ASU 2017-12 which provides targeted improvements to the hedge accounting model that more closely aligns the accounting and reporting for hedging relationships with risk management activities. In addition, ASU 2017-12 provides administrative relief by easing documentation requirements, simplifying the application of hedge accounting by expanding the application of the shortcut method, eliminating the separate measurement and reporting of hedge ineffectiveness and generally requiring the entire effect of the hedging instrument and the hedged item to be presented in the same income statement line item. We believe these changes will provide users with more useful information about the effect of our risk management activities on the financial statements.

Changes in fair value of a derivative instrument that has been designated and qualifies as a cash flow hedge, including any ineffectiveness, are recorded in accumulated other comprehensive income, net of tax. Amounts are reclassified from AOCI to the consolidated statements of income in the same line item used to present the earnings effect of the hedged item in the period or periods in which the hedged transaction affects earnings. Prior to 2019, the ineffective portion, if any, was reported in earnings immediately.

At the hedge’s inception, a formal assessment is performed to determine whether changes in the fair values or cash flows of the derivative instruments have been highly effective in offsetting changes in fair values or cash flows of the hedged items and whether they are expected to be highly effective in the future. At each reporting period thereafter, a statistical regression or qualitative analysis is performed to evaluate hedge effectiveness. If it is determined a derivative instrument has not been or will not continue to be highly effective as a hedge, hedge accounting is discontinued.

We also enter into interest rate swap agreements to meet the interest rate risk management needs of qualifying commercial loan customers. These agreements provide the customer the ability to convert from variable to fixed interest rates. We then enter into positions with a derivative counterparty in order to offset our exposure on the fixed components of the customer agreements. The credit risk associated with derivatives executed with customers is essentially the same as that involved in extending loans and is subject to normal credit policies and monitoring. We seek to minimize counterparty credit risk by entering into transactions with only high-quality institutions and using collateral agreements and other contract provisions. These arrangements meet the definition of derivatives, but are not designated as qualifying hedging relationships. The interest rate swap agreement with the loan customer and with the counterparty are reported at fair value in other assets and other liabilities on the Consolidated Balance Sheets with any resulting gain or loss recorded in current period earnings as other income.

Certain of our residential mortgage loans are originated or purchased for sale in the secondary mortgage loan market. We make an automatic election to account for all originated or purchased residential mortgage loans held for sale under the FVO. The FVO election is intended to better reflect the underlying economics and better facilitate the economic hedging of the loans. The FVO is applied on an instrument by instrument basis and is an irrevocable election. Additionally, with the election of the FVO, fees and costs associated with the origination and acquisition of residential mortgage loans held for sale are expensed as incurred, rather than deferred. Changes in fair value under the FVO are recorded in mortgage banking operations non-interest income on the consolidated statements of income. Fair value is determined on the basis of rates obtained in the respective secondary market for the type of loan held for sale. Gain or loss on the sale of loans is recorded in mortgage banking operations non-interest income. Interest income on loans held for sale is recorded in interest income.

We routinely issue interest rate lock commitments for residential mortgage loans that we intend to sell. These interest rate lock commitments are considered derivatives. We also enter into loan sale commitments to sell these loans when funded to mitigate the risk that the market value of residential mortgage loans may decline between the time the rate commitment is issued to the customer and the time we sell the loan. These loan sale commitments are also derivatives. Both types of derivatives are recorded at fair value on the Consolidated Balance Sheets with changes in fair value recorded in mortgage banking operations non-interest income.

We also originate loans guaranteed by the SBA for the purchase of businesses, business startups, business expansion, equipment, and working capital. All SBA loans are underwritten and documented as prescribed by the SBA. SBA loans originated with the intention to sell on the secondary market are classified as held for sale and carried at the lower of cost or fair value. At the time of the sale, we allocate the carrying value of the entire loan between the guaranteed portion sold and the unguaranteed portion retained based on their relative fair value which results in a discount recorded on the retained portion of the loan. The guaranteed portion is typically sold at a premium and the gain is recognized in other income for any net premium received in excess of the relative fair value of the portion of the loan transferred. The net carrying value of the retained portion of the loans is included in the appropriate commercial loan classification for disclosure purposes.

Loans we intend to hold for the foreseeable future or until maturity or payoff are reported at their outstanding principal balances, net of any unearned income, deferred origination fees or costs, or premium or discounts on purchased loans. Interest income on loans is computed over the term of the loans using the effective interest method. Loan origination fees or costs and premiums or discounts are deferred and amortized over the term of the loan or loan commitment period as an adjustment to the related loan yield.

Interest is not accrued on loans where collectability is uncertain. We discontinue interest accruals on loans generally when principal or interest is due and has remained unpaid for a certain number of days unless the loan is both well secured and in the process of collection. Commercial loans are placed on non-accrual at 90 days, installment loans are placed on non-accrual at 120 days and residential mortgages and consumer lines of credit are generally placed on non-accrual at 180 days. Past due status is based on the contractual terms of the loan.

When a loan is placed on non-accrual status, all unpaid interest is reversed against interest income and the amortization of deferred fees and costs is suspended. Payments subsequently received are generally applied to either principal or interest or both, depending on management’s evaluation of collectability. A loan is returned to accrual status when principal and interest are no longer past due and collectability is probable. This generally requires a sustained period of timely principal and interest payments.

We consider a loan impaired when, based on current information and events, it is probable that we will be unable to collect the scheduled payments of principal or interest when due according to the contractual terms of the loan agreement. Factors considered in determining impairment include payment status, collateral value and the probability of collecting scheduled principal and interest payments when due. The impairment loss is measured by either the present value of expected future cash flows discounted at the loan’s effective interest rate, the loan’s obtainable market price, or the fair value of the collateral, less estimated selling costs, if the loan is collateral dependent. Purchased credit impaired loans are not classified as non-performing assets as the loans are considered to be performing.

Restructured loans are those in which concessions of terms have been made as a result of deterioration in a borrower’s financial condition. In general, the modification or restructuring of a debt constitutes a TDR if we for economic or legal reasons related to the borrower’s financial difficulties grant a concession to the borrower that we would not otherwise consider under current market conditions. Debt restructurings or loan modifications for a borrower occur in the normal course of business and do not necessarily constitute TDRs. To designate a loan as a TDR, the presence of both borrower financial distress and a concession of terms must exist. Additionally, a loan designated as a TDR does not necessarily result in the automatic placement of the loan on non-accrual status. When the full collection of principal and interest is reasonably assured on a loan designated as a TDR and the borrower does not otherwise meet the criteria for non-accrual status, we will continue to accrue interest on the loan. A restructured acquired loan that is accounted for as a component of a pool is not considered a TDR.

The allowance for credit losses is established as losses are estimated to have occurred through a provision charged to earnings. Loan losses are charged-off against the allowance for credit losses when management believes the uncollectability of a loan balance is confirmed. Subsequent recoveries, if any, are credited to the allowance for credit losses. Allowances for impaired commercial loans over $1.0 million are generally determined based on collateral values or the present value of estimated cash flows. All other impaired loans are evaluated in the aggregate based on loan segment loss given default. Changes in the allowance for credit losses related to impaired loans are charged or credited to the provision for credit losses.

The allowance for credit losses is maintained at a level that, in management’s judgment, is believed appropriate to absorb probable losses associated with specifically identified loans, as well as estimated probable credit losses inherent in the remainder of the loan portfolio. The appropriateness of the allowance for credit losses is based on management’s evaluation of potential loan losses in the loan portfolio, which includes an assessment of past experience, current economic conditions in specific industries and geographic areas, general economic conditions, known and inherent risks in the loan portfolio, the estimated value of underlying collateral and residuals and changes in the composition of the loan portfolio. Determination of the allowance for credit losses is inherently subjective as it requires significant estimates, including the amounts and timing of expected future cash flows on impaired loans, estimated losses on pools of homogeneous loans based on transition matrices with predefined loss emergence and lookback periods, and consideration of qualitative factors, all of which are susceptible to significant change.

Loans acquired in a business combination (impaired and non-impaired) are initially recorded at their acquisition-date fair values. Fair values are based on a discounted cash flow methodology that involves assumptions and judgments as to credit risk, default rates, loss severity, collateral values, discount rates, payment speeds, prepayment risk, and liquidity risk.

The carryover of allowance for credit losses related to loans acquired in a business combination is prohibited as any credit losses in the loans are included in the determination of the fair value of the loans at the acquisition date. The allowance for credit losses on loans acquired in a business combination reflects only those losses incurred after acquisition and represents the present value of cash flows expected at acquisition that is no longer expected to be collected.

Any loans acquired in a business combination that were not individually in the scope of ASC 310-30 because they didn’t meet the criteria above were pooled into groups of similar loans based on various factors including borrower type, loan purpose, and collateral type. For these pools, we used certain loan information, including outstanding principal balance, estimated expected losses, weighted average maturity, weighted average margin, and weighted average interest rate along with estimated prepayment rates, probability of default and loss given default to estimate the expected cash flow for each loan pool. We believe analogizing to ASC 310-30 is the more appropriate option to follow in accounting for discount accretion on non-impaired loans acquired in a business combination other than revolving loans and therefore account for such loans in accordance with ASC 310-30. ASC 310-30 guidance does not apply to revolving loans. Consequently, discount accretion on revolving loans acquired is accounted for using the ASC 310-20 approach.

The excess of cash flows expected to be collected at acquisition over recorded fair value is referred to as the accretable yield. The accretable yield is recognized into income over the remaining life of the loan, or pool of loans, using an effective yield method, if the timing and/or amount of cash flows expected to be collected can be reasonably estimated (the accretion model). The difference between the loan’s total scheduled principal and interest payments over all cash flows expected at acquisition is referred to as the non-accretable difference. The non-accretable difference represents contractually required principal and interest payments which we do not expect to collect.

Over the life of the acquired loan, we continue to estimate cash flows expected to be collected. Decreases in expected cash flows, other than from prepayments or rate adjustments, are recognized as impairments through a charge to the provision for credit losses resulting in an increase in the allowance for credit losses. Subsequent improvements in cash flows result in first, reversal of existing valuation allowances recognized subsequent to acquisition, if any, and next, an increase in the amount of accretable yield to be subsequently recognized on a prospective basis over the loan’s remaining life.

Loans acquired in a business combination that met the criteria for non-accrual of interest prior to acquisition are considered performing upon acquisition, regardless of whether the customer is contractually delinquent, if we can reasonably estimate the timing and amount of expected cash flows on such loans. Accordingly, we do not consider contractually delinquent purchased credit impaired loans to be non-accrual or non-performing and continue to recognize interest income on these loans using the accretion model.

Premises and equipment are stated at cost less accumulated depreciation. Depreciation is computed using the straight-line method over the asset’s estimated useful life. Leasehold improvements are expensed over the lesser of the asset’s estimated useful life or the term of the lease including renewal periods when reasonably assured. Useful lives are dependent upon the nature and condition of the asset and range from 3 to 39 years. Maintenance and repairs are charged to expense as incurred, while major improvements are capitalized and amortized to expense over the identified useful life.

We evaluate fees paid for cloud computing arrangements to determine if those arrangements include the purchase of or license to use software that should be accounted for separately as internal-use software. If a contract includes the purchase or license to use software that should be accounted for separately as internal-use software, the contract is amortized over the software’s identified useful life in amortization of intangibles. For contracts that do not include a software license, the contract is accounted for as a service contract with fees paid recorded in other non-interest expense.

In the third quarter of 2018, we early adopted, on a prospective basis, ASU 2018-15 which allows for implementation costs for activities performed in cloud computing arrangements that are a service contract to be accounted for under the internal-use software guidance which allows for certain implementation costs to be capitalized depending on the nature of the costs and the project stage. Prior to the adoption of ASU 2018-15 all implementation costs for cloud computing arrangements that were a service contract were expensed as incurred.

OREO is comprised principally of commercial and residential real estate properties obtained in partial or total satisfaction of loan obligations. OREO acquired in settlement of indebtedness is included in other assets initially at the lower of estimated fair value of the asset less estimated selling costs or the carrying amount of the loan. Changes to the value subsequent to transfer are recorded in non-interest expense along with direct operating expenses. Gains or losses not previously recognized resulting from sales of OREO are recognized in non-interest income on the date of sale.

Goodwill represents the excess of the cost of an acquisition over the fair value of the net assets acquired. Other intangible assets represent purchased assets that lack physical substance but can be distinguished from goodwill because of contractual or other legal rights. Intangible assets that have finite lives, such as core deposit intangibles, customer relationship intangibles and renewal lists, are amortized over their estimated useful lives and subject to periodic impairment testing. Core deposit intangibles are primarily amortized over ten years using accelerated methods. Customer renewal lists are amortized over their estimated useful lives which range from eight to thirteen years.

Goodwill and other intangibles are subject to impairment testing at the reporting unit level, which must be conducted at least annually. We perform impairment testing during the fourth quarter of each year, or more frequently if impairment indicators exist. We also continue to monitor other intangibles for impairment and to evaluate carrying amounts, as necessary.

Determining the fair value of a reporting unit under the goodwill impairment test is judgmental and often involves the use of significant estimates and assumptions. Similarly, estimates and assumptions are used in determining the fair value of other intangible assets. Estimates of fair value are primarily determined using discounted cash flows, market comparisons and recent transactions. These approaches use significant estimates and assumptions including projected future cash flows, discount rates reflecting the market rate of return, projected growth rates and determination and evaluation of appropriate market comparables. However, future events could cause us to conclude that goodwill or other intangibles have become impaired, which would result in recording an impairment loss. Any resulting impairment loss could have a material adverse impact on our financial condition and results of operations.

We have two primary classes of servicing rights, residential mortgage loan servicing and SBA-guaranteed loan servicing. We recognize the right to service residential mortgage loans and SBA-guaranteed loans for others as an asset whether we purchase the servicing rights or as a result from a sale of loans that we originated or purchased when the servicing is contractually separated from the underlying loan and retained by us.

We initially record servicing rights at fair value in other assets on the Consolidated Balance Sheets. Subsequently, servicing rights are measured at the lower of cost or fair value. Servicing rights are amortized in proportion to, and over the period of, estimated net servicing income in mortgage banking operations non-interest income for residential mortgage loans and other non-interest income for SBA-guaranteed loans. The amount and timing of estimated future net cash flows are updated based on actual results and updated projections.

Impairment, if any, is recognized when carrying value exceeds the fair value as determined by calculating the present value of expected net future cash flows. If impairment exists at the pool level for residential mortgage loans or on an aggregate basis for SBA-guaranteed loans, the servicing right is written down through a valuation allowance and is charged against mortgage banking operations non-interest income or other non-interest income, respectively.

We have purchased life insurance policies on certain current and former directors, officers and employees for which the Corporation is the owner and beneficiary. These policies are recorded in the Consolidated Balance Sheets at their cash surrender value, or the amount that could be realized by surrendering the policies. Tax-exempt income from death benefits and changes in the net cash surrender value are recorded in bank owned life insurance non-interest income.

We invest in various affordable housing projects that qualify for LIHTCs. The net investments are recorded in other assets on the Consolidated Balance Sheets. These investments generate a return through the realization of federal tax credits. We use the proportional amortization method to account for a majority of our investments in these entities. LIHTCs that do not meet the requirements of the proportional amortization method are recognized using the equity method. Our net investment in LIHTCs was $59.6 million and $43.7 million at December 31, 2019 and 2018, respectively. Our unfunded commitments in LIHTCs were $60.1 million and $57.0 million at December 31, 2019 and 2018, respectively.

We determine if an arrangement is, or contains, a lease at inception of the contract. As a lessee, we consider a contract to be, or contain, a lease if the contract conveys the right to control the use of an identified asset in exchange for consideration. We recognize in our Consolidated Balance Sheets the obligation to make lease payments and a right-of-use asset representing our right to use the underlying asset for the lease term. For an operating lease, the right-of-use asset and lease liability are included in other assets and other liabilities, respectively. Finance leases are included in premises and equipment, and other liabilities. We do not record leases with an initial term of 12 months or less on the Consolidated Balance Sheets, instead we recognize lease expense for these leases on a straight-line basis over the lease term. For leases that commenced before January 1, 2019, we have applied the modified retrospective transition method which resulted in comparative information not being restated. The new standard provides a number of optional practical expedients in transition. We elected the ‘package of practical expedients’, which permits us to not reassess our prior conclusions about lease identification, lease classification and initial direct costs.

Right-of-use assets and liabilities are initially measured at the present value of lease payments over the lease term, discounted using the interest rate implicit in the lease at the commencement date. Right-of-use assets are adjusted for any lease payments made prior to lease commencement, lease incentives, and accrued rent. If the rate implicit in the lease cannot be readily determined, we discount the lease using our incremental borrowing rate which is derived by reference to FNB's secured borrowing rate. Our leases may include options to extend or terminate the lease. When it is reasonably certain that we will exercise such an option, the lease term includes those periods. Lease expense for operating leases is recognized on a straight-line basis over the lease term. Lease expense for finance leases is recognized using the effective interest method. Certain of our lease agreements include variable rental payments based on a percentage of transactions and others include variable rental payments that periodically adjust to rates and charges stated in the agreements. Variable costs, such as maintenance expenses, property taxes, property insurance, transaction-based lease payments and index-based rate increases, are expensed as incurred. Right-of-use assets are reviewed for impairment when events or circumstances indicate that the carrying amount may not be recoverable. For operating leases, if deemed impaired, the right-of-use asset is written down and the remaining balance is subsequently amortized on a straight-line basis.

As a lessor, when a lease meets certain criteria indicating that we effectively have transferred control of the underlying asset to the customer, the lease is classified as a sales-type lease. When a lease does not meet the criteria for a sales-type lease but meets the criteria of a direct financing lease, the lease is classified as a direct financing lease. When none of the required criteria for sales-type lease or direct-financing lease are met, the lease is classified as an operating lease.

guaranteed by the customer or any other third party unrelated to us and the unguaranteed residual value of the underlying asset. Operating lease income is recognized over the lease term on a straight-line basis. We do not evaluate whether sales taxes and similar taxes imposed by a governmental authority on lease transactions and collected by us are our primary obligation as owner of the underlying leased asset and exclude from lease income all taxes collected.

We file a consolidated federal income tax return. The provision for federal and state income taxes is based on income reported on the Consolidated Financial Statements, rather than the amounts reported on the respective income tax returns. DTAs and DTLs are computed using tax rates expected to apply to taxable income in the years in which those assets and liabilities are expected to be realized. The effect on DTAs and DTLs resulting from a change in tax rates is recognized as income or expense in the period that the change in tax rates is enacted. Beginning in the fourth quarter of 2017, we made an accounting policy election to reclassify the stranded tax effects that relate to a change in the federal tax rate from AOCI to retained earnings in accordance with newly adopted accounting guidance. We believe this change in accounting policy reduces the cost and complexity of accounting for stranded tax effects due to a change in federal tax rates.

We make certain estimates and judgments in determining income tax expense for financial statement purposes. These estimates and judgments are applied in the calculation of certain tax credits and in the calculation of the deferred income tax expense or benefit associated with certain deferred tax assets and liabilities. Significant changes to these estimates may result in an increase or decrease to our tax provision in a subsequent period. We recognize interest and/or penalties related to income tax matters in income tax expense.

We assess the likelihood that we will be able to recover our DTAs. If recovery is not likely, we will increase our valuation allowance against the DTAs that are unlikely to be recovered by recording a provision for income taxes. We believe that we will ultimately recover the DTAs recorded on our Consolidated Balance Sheets.

We periodically review the tax positions we take on our tax return and apply a more likely than not recognition threshold for all tax positions that are uncertain. The amount recognized in the Consolidated Financial Statements is the largest amount of tax benefit that is greater than 50% likely of being realized on examination. For tax positions not meeting the more likely than not test, no tax benefit is recorded.

Diluted earnings per common share is calculated by dividing net income available to common stockholders by the weighted average number of shares of common stock outstanding, adjusted for the dilutive effect of potential common shares issuable for stock options, warrants and restricted shares, as calculated using the treasury stock method. Adjustments to net income available to common stockholders and the weighted average number of shares of common stock outstanding are made only when such adjustments dilute earnings per common share.

We sponsor retirement plans for our employees. The calculation of the obligations and related expenses under these plans requires use of actuarial valuation methods and assumptions. The plans utilize assumptions and methods including reflecting trust assets at their fair value for the qualified pension plans and recognizing the overfunded and underfunded status of the

Our stock-based compensation awards require the measurement and recognition of compensation expense, based on estimated fair values, for all stock-based awards, including stock options and restricted stock units, made to employees and stock awards made to directors. Generally, these restricted stock unit awards to employees vest over a three-year service period and the stock awards made to directors vest immediately.

We are required to estimate the fair value of stock-based awards on the date of grant. For time-based awards, the value of the award is recognized as expense in our Consolidated Statements of Income over the shorter of requisite service periods or the period through the date that the employee first becomes eligible to retire.

Beginning in 2018, we granted restricted stock unit awards with multiple-conditions, both performance and market conditions. These awards were accounted for by considering the market condition in the grant date fair value and recognizing compensation expense over the service period based on the grant date fair value and the probability that the performance condition will be met.