Nature of Operations and Basis of Presentation (Policies)	3 Months Ended
Mar. 31, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	The unaudited consolidated interim financial statements have been prepared in accordance with U.S. generally accepted accounting principles ("GAAP") for interim financial reporting and with the instructions to Form 10-Q and Regulation S-X promulgated by the SEC. Certain financial information that is included in our Annual Report on Form 10-K for the year ended December 31, 2023, including certain financial statement footnote disclosures, is not required by the rules and regulations of the SEC for interim financial reporting and has been condensed or omitted.
Use of Estimates	The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates. The financial statement categories that are most dependent on management estimates and assumptions include: investments; deferred policy acquisition costs; reinsurance receivables and recoverables; loss settlement expenses; and pension and postretirement benefit obligations.
Segment Information	Our property and casualty insurance business is reported as one business segment. The property and casualty insurance business profit or loss is consistent with consolidated reporting as disclosed on the Consolidated Statements of Income and Comprehensive Income. We analyze the property and casualty insurance business results based on profitability (i.e., loss ratios), expenses and return on equity. The Company's property and casualty insurance business was determined using a management approach to make decisions on operating matters, including allocating resources, assessing performance, determining which products to market and sell, determining distribution networks with insurance agents and monitoring the regulatory environment. The property and casualty insurance business products have similar economic characteristics and use a similar marketing and distribution strategy with our independent agents. We will continue to evaluate our operations on the basis of both statutory accounting principles prescribed or permitted by our states of domicile and GAAP.
Cash and Cash Equivalents	For purposes of reporting cash flows, cash and cash equivalents include cash, money market accounts and non-negotiable certificates of deposit with original maturities of three months or less.
Deferred Policy Acquisition Costs (DAC)	Certain costs associated with underwriting new business (primarily commissions, premium taxes and variable underwriting and policy issue expenses associated with successful acquisition efforts) are deferred. Property and casualty insurance policy acquisition costs deferred are amortized as premium revenue is recognized. The method followed in computing DAC limits the amount of such deferred costs to their estimated realizable value. This takes into account the premium to be earned, losses and loss settlement expenses expected to be incurred and certain other costs expected to be incurred as the premium is earned.
Other Intangible Assets	Our other intangible assets, which consist primarily of agency relationships, trade names, state insurance licenses, and software, are being amortized using the straight-line method over periods ranging from two years to 15 years, with the exception of state insurance licenses, which are indefinite-lived and not amortized.
Income Taxes	Deferred tax assets and liabilities are established based on differences between the financial statement bases of assets and liabilities and the tax bases of those same assets and liabilities, using the currently enacted statutory tax rates. Deferred income tax expense is measured by the year-to-year change in the net deferred tax asset or liability, except for certain changes in deferred tax amounts that affect stockholders' equity and do not impact federal income tax expense. We reported a consolidated federal income tax expense of $2,782 for the three-month period ended March 31, 2024 compared to an income tax benefit of $695 during the same period of 2023. Our effective tax rate for 2024 and 2023 is different than the federal statutory rate of 21 percent, due principally to the net effect of tax-exempt municipal bond interest income. The Company performs a quarterly review of its tax positions and makes a determination of whether it is more likely than not that the tax position will be sustained upon examination. If, based on this review, it appears not more likely than not that the positions will be sustained, the Company will calculate any unrecognized tax benefits and, if necessary, calculate and accrue any related interest and penalties. We did not recognize any liability for unrecognized tax benefits at March 31, 2024 or December 31, 2023. In addition, we have not accrued for interest and penalties related to unrecognized tax benefits. However, if interest and penalties would need to be accrued related to unrecognized tax benefits, such amounts would be recognized as a component of federal income tax expense. Deferred tax assets are reduced by a valuation allowance when management believes it is more likely than not that some, or all, of the deferred taxes will not be realized. After considering all positive and negative evidence of taxable income in the carryback and carryforward periods and our tax planning strategy of holding debt securities with unrealized losses to maturity or recovery, we believe it is more likely than not that all the deferred assets will be realized. As a result, we have no valuation allowance at March 31, 2024 or December 31, 2023. For each of the three-month periods ended March 31, 2024 and 2023, we made payments for income taxes totaling $12. We did not receive a federal tax refund for the three-month periods ended March 31, 2024 and 2023. We file a consolidated federal income tax return. We also file income tax returns in various state jurisdictions. We are no longer subject to federal or state income tax examination for years before 2018.
Leases	The Company determines if a contract contains a lease at inception of the contract. The Company's inventory of leases consists of operating leases which are recorded as a lease obligation liability disclosed in the "Accrued expenses and other liabilities" line on the Consolidated Balance Sheets and as a lease right-of-use asset disclosed in the "Other assets" line on the Consolidated Balance Sheets. The Company's operating leases consist of office space, vehicles, computer equipment and office equipment. The lease right-of-use asset represents the Company's right to use each underlying asset for the lease term and the lease obligation liability represents the Company's obligation over the lease term. The Company's lease obligation is recorded at the present value of the lease payments based on the term of the applied lease. Short-term leases of 12 months or less are recorded on the Consolidated Balance Sheets and lease payments are recognized on the Consolidated Statements of Income and Comprehensive Income.
Credit Losses	The Company recognizes credit losses for our available-for-sale fixed-maturity portfolio, reinsurance receivables, mortgage loans and premium receivables by setting up allowances which are remeasured each reporting period and recorded in the Consolidated Statements of Income and Comprehensive Income. For our available-for-sale fixed-maturity portfolio an allowance for credit losses is recorded net of available-for-sale fixed maturities in the Consolidated Balance Sheets and a corresponding credit loss recognized as a realized loss or gain in the Consolidated Statements of Income and Comprehensive Income. The Company determines if an allowance for credit losses is recorded based on a number of factors including current economic conditions, management's expectations of future economic conditions and performance indicators, such as market value versus amortized cost, investment spreads widening or contracting, rating actions, payment and default history. For more information on credit losses and the allowance for credit losses for our available-for-sale fixed-maturity portfolio, see Note 2 "Summary of Investments." An allowance for mortgage loan losses is established based on historical loss information of the collective pool of the Company's commercial mortgage loan investments which have similar risk characteristics. To calculate the allowance for mortgage loan losses, the Company starts with historical loan experience to predict the future expected losses and then layers on a market-linked adjustment. On a quarterly basis, quantitative credit risk metrics, including, for example, cash-flows, rent rolls and financial statements are reviewed for each loan to determine if it is performing in line with its expectations. This allowance is presented as a separate line in the Consolidated Balance Sheets beneath the asset value as well as presented net and recorded through "Net investment gains (losses)" in the Consolidated Statements of Income and Comprehensive Income. For more information on credit losses and the allowance for credit losses for our investment in mortgage loans see Note 3 "Fair Value of Financial Instruments." For reinsurance receivables, the Company's model estimates expected credit loss by multiplying the exposure at default by both the probability of default and loss given default ("LGD"). The LGD is estimated by the rating of the reinsurer, historical relationship with UFG, existence of letters of credit and known regulation for which the Company may be held accountable. The ultimate LGD percentage is estimated after considering Moody's experience with unsecured year one bond recovery rates from 1983-2017. The allowance calculated as of March 31, 2024 is recorded through the line "Reinsurance receivables and recoverables" in the Consolidated Balance Sheets and through the line "Other underwriting expenses" in the Consolidated Statements of Income and Other Comprehensive Income. With respect to premiums receivable, the Company utilizes an aging method to estimate credit losses. An allowance for doubtful accounts is based on a periodic evaluation of the aging and collectability of amounts due from agents and policyholders. "Premiums receivable" are presented in the Consolidated Balance Sheets net of an estimated allowance for doubtful accounts and recorded through "Other underwriting expenses" in the Consolidated Statements of Income and Comprehensive Income.
Subsequent Events	In the preparation of the accompanying financial statements, the Company has evaluated all material subsequent events or transactions that occurred after the balance sheet date through the date on which the financial statements were issued for potential recognition or disclosure in the Company's financial statements.
Recently Issued Accounting Standards	There were no recently issued accounting standards impacting our financial statements.
Fair Value of Financial Instruments	Current accounting guidance on fair value measurements includes the application of a fair value hierarchy that requires us to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. Our financial instruments that are recorded at fair value are categorized into a three-level hierarchy, which is based upon the priority of the inputs to the valuation technique. The fair value hierarchy gives the highest priority to quoted prices in active markets for identical assets (i.e., Level 1) and the lowest priority to unobservable inputs (i.e., Level 3). If the inputs used to measure fair value fall within different levels of the hierarchy, the category level is based on the lowest priority level input that is significant to the fair value measurement of the financial instrument. Financial instruments recorded at fair value are categorized in the fair value hierarchy as follows: •Level 1: Valuations are based on unadjusted quoted prices in active markets for identical financial instruments that we have the ability to access. •Level 2: Valuations are based on quoted prices for similar financial instruments, other than quoted prices included in Level 1, in markets that are not active or on inputs that are observable either directly or indirectly for the full term of the financial instrument. •Level 3: Valuations are based on pricing or valuation techniques that require inputs that are both unobservable and significant to the overall fair value measurement of the financial instrument. Such inputs may reflect management's own assumptions about the assumptions a market participant would use in pricing the financial instrument. We review our fair value hierarchy categorizations on a quarterly basis at which time the classification of certain financial instruments may change if the input observations have changed. Transfers between levels, if any, are recorded as of the beginning of the reporting period. To determine the fair value of the majority of our investments, we utilize prices obtained from independent, nationally recognized pricing services. We obtain one price for each security. When the pricing services cannot provide a determination of fair value for a specific security, we obtain non-binding price quotes from broker-dealers with whom we have had several years' experience and who have demonstrated knowledge of the subject security. In order to determine the proper classification in the fair value hierarchy, we obtain and evaluate the vendors' pricing procedures and inputs used to price the security, which include unadjusted quoted market prices for identical securities, such as a New York Stock Exchange closing price, and quoted prices for identical securities in markets that are not active. For fixed maturity securities, an evaluation of interest rates and yield curves observable at commonly quoted intervals, volatility, prepayment speeds, credit risks and default rates may also be performed. We have determined that these processes and inputs result in fair values and classifications consistent with the applicable accounting guidance on fair value measurements. When possible, we use quoted market prices to determine the fair value of fixed maturities, equity securities, trading securities and short-term investments. When quoted market prices do not exist, we base estimates of fair value on market information obtained from independent pricing services and brokers or on valuation techniques that are both unobservable and significant to the overall fair value measurement of the financial instrument. Such inputs may reflect management's own assumptions about the assumptions a market participant would use in pricing the financial instrument. Our valuation techniques are discussed in more detail throughout this section. The mortgage loan portfolio consists entirely of commercial mortgage loans. The fair value of our mortgage loans is determined by modeling performed by our third-party fund manager based on the stated principal and coupon payments provided for in the loan agreements. These cash flows are then discounted using an appropriate risk-adjusted discount rate to determine the security's fair value. Our other long-term investments consist primarily of our interests in limited liability partnerships that are recorded on the equity method of accounting. The fair value of the partnerships is obtained from the fund managers, which is based on the fair value of the underlying investments held in the partnerships. In management's opinion, these values represent a reasonable estimate of fair value. We have not adjusted the net asset value provided by the fund managers. For cash and cash equivalents and accrued investment income, carrying value is a reasonable estimate of fair value due to the short-term nature of these financial instruments. The Company formed a rabbi trust in 2014 to fund obligations under the United Fire & Casualty Company Supplemental Executive Retirement and Deferral Plan (the "Executive Retirement Plan"). Within the rabbi trust, corporate-owned life insurance ("COLI") policies are utilized as an investment vehicle and source of funding for the Company's Executive Retirement Plan. The COLI policies invest in mutual funds, which are priced daily by independent sources. As of March 31, 2024, the cash surrender value of the COLI policies was $12,482 which is equal to the fair value measured using Level 2 inputs, based on the underlying assets of the COLI policies, and is included in other assets in the Consolidated Balance Sheets. Our long-term debt is not carried in the Consolidated Balance Sheet at fair value. The fair value of our long-term debt is estimated using Level 2 inputs based on quoted prices for similar financial instruments. The fair value is estimated using a discounted cash flow analysis. The fair value of securities that are categorized as Level 1 is based on quoted market prices that are readily and regularly available. We use a market-based approach for valuing all of our Level 2 securities and submit them primarily to a third-party valuation service provider. Any of these securities not valued by this service provider are submitted to another third-party valuation service provider. Both service providers use a market approach to find pricing of similar financial instruments. The market inputs our service providers normally seek to value our securities include the following, listed in approximate order of priority: benchmark yields, reported trades, broker/dealer quotes, issuer spreads, two-sided markets, benchmark securities, bids, offers, and reference data including market research publications. The method and inputs for these securities classified as Level 2 are the same regardless of industry category, credit quality, duration, geographical concentration or economic characteristics. For our mortgage-backed securities, collateralized mortgage obligations and asset-backed securities, our service providers use additional market inputs to value these securities, including the following: new issue data, periodic payment information, monthly payment information, collateral performance and real estate analysis from third parties. Our service providers prioritize inputs based on market conditions, and not all inputs listed are available for use in the valuation process for each security on any given day. At least annually, we review the methodologies and assumptions used by our valuation service providers and verify that they are reasonable and representative of the fair value of the underlying securities held in the investment portfolio. We validate the prices obtained from independent pricing services and brokers prior to their use for reporting purposes by evaluating their reasonableness on a monthly basis. In addition, on a quarterly basis, we also test all securities in the portfolio and independently corroborate the valuations obtained from our third-party valuation service providers. Quarterly, we also perform deep dive analyses of the pricing method used by our third-party valuation service provider by selecting a random sample of securities by asset class and reviewing methodologies. In our opinion, the pricing obtained at March 31, 2024 and December 31, 2023 was reasonable. For the three-month period ended March 31, 2024, the change in our available-for-sale securities categorized as Level 1 and Level 2 is the result of investment purchases that were made using funds held in our money market accounts, disposals and the change in unrealized gains. Securities categorized as Level 3 include holdings in certain private placement fixed maturity securities for which an active market does not currently exist. The fair value of our Level 3 private placement securities is determined by management relying on pricing received from our independent pricing services and brokers consistent with the process to estimate fair value for Level 2 securities. However, securities are categorized as Level 3 if these quotes cannot be corroborated by other market observable data due to the unobservable nature of the brokers' valuation processes. A change in significant unobservable inputs may result in a significantly higher or lower fair value measurement as of the reporting date.
Earnings Per Common Share	Basic earnings per share is computed by dividing net income by the weighted-average number of common shares outstanding during the reporting period. Diluted earnings per share gives effect to all dilutive common shares outstanding during the reporting period. The dilutive shares we consider in our diluted earnings per share calculation relate to our outstanding stock options, restricted stock awards and restricted stock unit awards. We determine the dilutive effect of our outstanding stock options using the "treasury stock" method. Under this method, we assume the exercise of all of the outstanding stock options whose exercise price is less than the weighted-average market value of our common stock during the reporting period. This method also assumes that the proceeds from the hypothetical stock option exercises are used to repurchase shares of our common stock at the weighted-average market value of the stock during the reporting period. The net of the assumed stock options exercised and assumed common shares repurchased represents the number of dilutive common shares, which we add to the denominator of the earnings per share calculation.

Nature of Operations and Basis of Presentation (Policies)

3 Months Ended

Mar. 31, 2024

Organization, Consolidation and Presentation of Financial Statements [Abstract]

The unaudited consolidated interim financial statements have been prepared in accordance with U.S. generally accepted accounting principles ("GAAP") for interim financial reporting and with the instructions to Form 10-Q and Regulation S-X promulgated by the SEC. Certain financial information that is included in our Annual Report on Form 10-K for the year ended December 31, 2023, including certain financial statement footnote disclosures, is not required by the rules and regulations of the SEC for interim financial reporting and has been condensed or omitted.

Use of Estimates

The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates. The financial statement categories that are most dependent on management estimates and assumptions include: investments; deferred policy acquisition costs; reinsurance receivables and recoverables; loss settlement expenses; and pension and postretirement benefit obligations.

Segment Information

Our property and casualty insurance business is reported as one business segment. The property and casualty insurance business profit or loss is consistent with consolidated reporting as disclosed on the Consolidated Statements of Income and Comprehensive Income. We analyze the property and casualty insurance business results based on profitability (i.e., loss ratios), expenses and return on equity. The Company's property and casualty insurance business was determined using a management approach to make decisions on operating matters, including allocating resources, assessing performance, determining which products to market and sell, determining distribution networks with insurance agents and monitoring the regulatory environment. The property and casualty insurance business products have similar economic characteristics and use a similar marketing and distribution strategy with our independent agents. We will continue to evaluate our operations on the basis of both statutory accounting principles prescribed or permitted by our states of domicile and GAAP.

Cash and Cash Equivalents

For purposes of reporting cash flows, cash and cash equivalents include cash, money market accounts and non-negotiable certificates of deposit with original maturities of three months or less.

Deferred Policy Acquisition Costs (DAC)

Certain costs associated with underwriting new business (primarily commissions, premium taxes and variable underwriting and policy issue expenses associated with successful acquisition efforts) are deferred.

Property and casualty insurance policy acquisition costs deferred are amortized as premium revenue is recognized. The method followed in computing DAC limits the amount of such deferred costs to their estimated realizable value. This takes into account the premium to be earned, losses and loss settlement expenses expected to be incurred and certain other costs expected to be incurred as the premium is earned.

Other Intangible Assets

Our other intangible assets, which consist primarily of agency relationships, trade names, state insurance licenses, and software, are being amortized using the straight-line method over periods ranging from two years to 15 years, with the exception of state insurance licenses, which are indefinite-lived and not amortized.

Income Taxes

Deferred tax assets and liabilities are established based on differences between the financial statement bases of assets and liabilities and the tax bases of those same assets and liabilities, using the currently enacted statutory tax rates. Deferred income tax expense is measured by the year-to-year change in the net deferred tax asset or liability, except for certain changes in deferred tax amounts that affect stockholders' equity and do not impact federal income tax expense.

We reported a consolidated federal income tax expense of $2,782 for the three-month period ended March 31, 2024 compared to an income tax benefit of $695 during the same period of 2023. Our effective tax rate for 2024 and 2023 is different than the federal statutory rate of 21 percent, due principally to the net effect of tax-exempt municipal bond interest income.

The Company performs a quarterly review of its tax positions and makes a determination of whether it is more likely than not that the tax position will be sustained upon examination. If, based on this review, it appears not more likely than not that the positions will be sustained, the Company will calculate any unrecognized tax benefits and, if necessary, calculate and accrue any related interest and penalties. We did not recognize any liability for unrecognized tax benefits at March 31, 2024 or December 31, 2023. In addition, we have not accrued for interest and penalties related to unrecognized tax benefits. However, if interest and penalties would need to be accrued related to unrecognized tax benefits, such amounts would be recognized as a component of federal income tax expense.

Deferred tax assets are reduced by a valuation allowance when management believes it is more likely than not that some, or all, of the deferred taxes will not be realized. After considering all positive and negative evidence of taxable income in the carryback and carryforward periods and our tax planning strategy of holding debt securities with unrealized losses to maturity or recovery, we believe it is more likely than not that all the deferred assets will be realized. As a result, we have no valuation allowance at March 31, 2024 or December 31, 2023.

For each of the three-month periods ended March 31, 2024 and 2023, we made payments for income taxes totaling $12. We did not receive a federal tax refund for the three-month periods ended March 31, 2024 and 2023.

We file a consolidated federal income tax return. We also file income tax returns in various state jurisdictions. We are no longer subject to federal or state income tax examination for years before 2018.

Leases

The Company determines if a contract contains a lease at inception of the contract. The Company's inventory of leases consists of operating leases which are recorded as a lease obligation liability disclosed in the "Accrued expenses and other liabilities" line on the Consolidated Balance Sheets and as a lease right-of-use asset disclosed in the "Other assets" line on the Consolidated Balance Sheets. The Company's operating leases consist of office space, vehicles, computer equipment and office equipment. The lease right-of-use asset represents the Company's right to use each underlying asset for the lease term and the lease obligation liability represents the Company's obligation over the lease term. The Company's lease obligation is recorded at the present value of the lease payments based on the term of the applied lease. Short-term leases of 12 months or less are recorded on the Consolidated Balance Sheets and lease payments are recognized on the Consolidated Statements of Income and Comprehensive Income.

Credit Losses

The Company recognizes credit losses for our available-for-sale fixed-maturity portfolio, reinsurance receivables, mortgage loans and premium receivables by setting up allowances which are remeasured each reporting period and recorded in the Consolidated Statements of Income and Comprehensive Income.

For our available-for-sale fixed-maturity portfolio an allowance for credit losses is recorded net of available-for-sale fixed maturities in the Consolidated Balance Sheets and a corresponding credit loss recognized as a realized loss or gain in the Consolidated Statements of Income and Comprehensive Income. The Company determines if an allowance for credit losses is recorded based on a number of factors including current economic conditions, management's expectations of future economic conditions and performance indicators, such as market value versus amortized cost, investment spreads widening or contracting, rating actions, payment and default history. For more information on credit losses and the allowance for credit losses for our available-for-sale fixed-maturity portfolio, see Note 2 "Summary of Investments."

An allowance for mortgage loan losses is established based on historical loss information of the collective pool of the Company's commercial mortgage loan investments which have similar risk characteristics. To calculate the allowance for mortgage loan losses, the Company starts with historical loan experience to predict the future expected losses and then layers on a market-linked adjustment. On a quarterly basis, quantitative credit risk metrics, including, for example, cash-flows, rent rolls and financial statements are reviewed for each loan to determine if it is performing in line with its expectations. This allowance is presented as a separate line in the Consolidated Balance Sheets beneath the asset value as well as presented net and recorded through "Net investment gains (losses)" in the Consolidated Statements of Income and Comprehensive Income. For more information on credit losses and the allowance for credit losses for our investment in mortgage loans see Note 3 "Fair Value of Financial Instruments."

For reinsurance receivables, the Company's model estimates expected credit loss by multiplying the exposure at default by both the probability of default and loss given default ("LGD"). The LGD is estimated by the rating of the reinsurer, historical relationship with UFG, existence of letters of credit and known regulation for which the Company may be held accountable. The ultimate LGD percentage is estimated after considering Moody's experience with unsecured year one bond recovery rates from 1983-2017. The allowance calculated as of March 31, 2024 is recorded through the line "Reinsurance receivables and recoverables" in the Consolidated Balance Sheets and through the line "Other underwriting expenses" in the Consolidated Statements of Income and Other Comprehensive Income.

With respect to premiums receivable, the Company utilizes an aging method to estimate credit losses. An allowance for doubtful accounts is based on a periodic evaluation of the aging and collectability of amounts due from agents and policyholders. "Premiums receivable" are presented in the Consolidated Balance Sheets net of an estimated allowance for doubtful accounts and recorded through "Other underwriting expenses" in the Consolidated Statements of Income and Comprehensive Income.

Subsequent Events

In the preparation of the accompanying financial statements, the Company has evaluated all material subsequent events or transactions that occurred after the balance sheet date through the date on which the financial statements were issued for potential recognition or disclosure in the Company's financial statements.

Recently Issued Accounting Standards

There were no recently issued accounting standards impacting our financial statements.

Fair Value of Financial Instruments

Current accounting guidance on fair value measurements includes the application of a fair value hierarchy that requires us to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. Our financial instruments that are recorded at fair value are categorized into a three-level hierarchy, which is based upon the priority of the inputs to the valuation technique. The fair value hierarchy gives the highest priority to quoted prices in active markets for identical assets (i.e., Level 1) and the lowest priority to unobservable inputs (i.e., Level 3). If the inputs used to measure fair value fall within different levels of the hierarchy, the category level is based on the lowest priority level input that is significant to the fair value measurement of the financial instrument.

Financial instruments recorded at fair value are categorized in the fair value hierarchy as follows:

•Level 1: Valuations are based on unadjusted quoted prices in active markets for identical financial instruments that we have the ability to access.

•Level 2: Valuations are based on quoted prices for similar financial instruments, other than quoted prices included in Level 1, in markets that are not active or on inputs that are observable either directly or indirectly for the full term of the financial instrument.

•Level 3: Valuations are based on pricing or valuation techniques that require inputs that are both unobservable and significant to the overall fair value measurement of the financial instrument. Such inputs may reflect management's own assumptions about the assumptions a market participant would use in pricing the financial instrument.

We review our fair value hierarchy categorizations on a quarterly basis at which time the classification of certain financial instruments may change if the input observations have changed. Transfers between levels, if any, are recorded as of the beginning of the reporting period.

To determine the fair value of the majority of our investments, we utilize prices obtained from independent, nationally recognized pricing services. We obtain one price for each security. When the pricing services cannot provide a determination of fair value for a specific security, we obtain non-binding price quotes from broker-dealers with whom we have had several years' experience and who have demonstrated knowledge of the subject security.

In order to determine the proper classification in the fair value hierarchy, we obtain and evaluate the vendors' pricing procedures and inputs used to price the security, which include unadjusted quoted market prices for identical securities, such as a New York Stock Exchange closing price, and quoted prices for identical securities in markets that are not active. For fixed maturity securities, an evaluation of interest rates and yield curves observable at commonly quoted intervals, volatility, prepayment speeds, credit risks and default rates may also be performed. We have determined that these processes and inputs result in fair values and classifications consistent with the applicable accounting guidance on fair value measurements.

When possible, we use quoted market prices to determine the fair value of fixed maturities, equity securities, trading securities and short-term investments. When quoted market prices do not exist, we base estimates of fair value on market information obtained from independent pricing services and brokers or on valuation techniques that are both unobservable and significant to the overall fair value measurement of the financial instrument. Such inputs may reflect management's own assumptions about the assumptions a market participant would use in pricing the financial instrument. Our valuation techniques are discussed in more detail throughout this section.

The mortgage loan portfolio consists entirely of commercial mortgage loans. The fair value of our mortgage loans is determined by modeling performed by our third-party fund manager based on the stated principal and coupon payments provided for in the loan agreements. These cash flows are then discounted using an appropriate risk-adjusted discount rate to determine the security's fair value.

Our other long-term investments consist primarily of our interests in limited liability partnerships that are recorded on the equity method of accounting. The fair value of the partnerships is obtained from the fund managers, which is based on the fair value of the underlying investments held in the partnerships. In management's opinion, these values represent a reasonable estimate of fair value. We have not adjusted the net asset value provided by the fund managers.

For cash and cash equivalents and accrued investment income, carrying value is a reasonable estimate of fair value due to the short-term nature of these financial instruments.

The Company formed a rabbi trust in 2014 to fund obligations under the United Fire & Casualty Company Supplemental Executive Retirement and Deferral Plan (the "Executive Retirement Plan"). Within the rabbi trust, corporate-owned life insurance ("COLI") policies are utilized as an investment vehicle and source of funding for the Company's Executive Retirement Plan. The COLI policies invest in mutual funds, which are priced daily by independent sources. As of March 31, 2024, the cash surrender value of the COLI policies was $12,482 which is equal to the fair value measured using Level 2 inputs, based on the underlying assets of the COLI policies, and is included in other assets in the Consolidated Balance Sheets.

Our long-term debt is not carried in the Consolidated Balance Sheet at fair value. The fair value of our long-term debt is estimated using Level 2 inputs based on quoted prices for similar financial instruments. The fair value is estimated using a discounted cash flow analysis.

The fair value of securities that are categorized as Level 1 is based on quoted market prices that are readily and regularly available.

We use a market-based approach for valuing all of our Level 2 securities and submit them primarily to a third-party valuation service provider. Any of these securities not valued by this service provider are submitted to another third-party valuation service provider. Both service providers use a market approach to find pricing of similar financial instruments. The market inputs our service providers normally seek to value our securities include the following,

listed in approximate order of priority: benchmark yields, reported trades, broker/dealer quotes, issuer spreads, two-sided markets, benchmark securities, bids, offers, and reference data including market research publications. The method and inputs for these securities classified as Level 2 are the same regardless of industry category, credit quality, duration, geographical concentration or economic characteristics. For our mortgage-backed securities, collateralized mortgage obligations and asset-backed securities, our service providers use additional market inputs to value these securities, including the following: new issue data, periodic payment information, monthly payment information, collateral performance and real estate analysis from third parties. Our service providers prioritize inputs based on market conditions, and not all inputs listed are available for use in the valuation process for each security on any given day.

At least annually, we review the methodologies and assumptions used by our valuation service providers and verify that they are reasonable and representative of the fair value of the underlying securities held in the investment portfolio. We validate the prices obtained from independent pricing services and brokers prior to their use for reporting purposes by evaluating their reasonableness on a monthly basis. In addition, on a quarterly basis, we also test all securities in the portfolio and independently corroborate the valuations obtained from our third-party valuation service providers. Quarterly, we also perform deep dive analyses of the pricing method used by our third-party valuation service provider by selecting a random sample of securities by asset class and reviewing methodologies. In our opinion, the pricing obtained at March 31, 2024 and December 31, 2023 was reasonable.

For the three-month period ended March 31, 2024, the change in our available-for-sale securities categorized as Level 1 and Level 2 is the result of investment purchases that were made using funds held in our money market accounts, disposals and the change in unrealized gains.

Securities categorized as Level 3 include holdings in certain private placement fixed maturity securities for which an active market does not currently exist. The fair value of our Level 3 private placement securities is determined by management relying on pricing received from our independent pricing services and brokers consistent with the process to estimate fair value for Level 2 securities. However, securities are categorized as Level 3 if these quotes cannot be corroborated by other market observable data due to the unobservable nature of the brokers' valuation processes. A change in significant unobservable inputs may result in a significantly higher or lower fair value measurement as of the reporting date.

Earnings Per Common Share

Basic earnings per share is computed by dividing net income by the weighted-average number of common shares outstanding during the reporting period. Diluted earnings per share gives effect to all dilutive common shares outstanding during the reporting period. The dilutive shares we consider in our diluted earnings per share calculation relate to our outstanding stock options, restricted stock awards and restricted stock unit awards.

We determine the dilutive effect of our outstanding stock options using the "treasury stock" method. Under this method, we assume the exercise of all of the outstanding stock options whose exercise price is less than the weighted-average market value of our common stock during the reporting period. This method also assumes that the proceeds from the hypothetical stock option exercises are used to repurchase shares of our common stock at the weighted-average market value of the stock during the reporting period. The net of the assumed stock options exercised and assumed common shares repurchased represents the number of dilutive common shares, which we add to the denominator of the earnings per share calculation.