Significant Accounting Policies (Policies)	12 Months Ended
Dec. 31, 2020
Significant Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The consolidated financial statements have been prepared on the accrual basis of accounting in accordance with U.S. generally accepted accounting principles (“GAAP”). The consolidated financial statements include the accounts of the Company and its wholly-owned subsidiaries including: Gabelli Funds, GAMCO Asset, G.distributors, and GAMCO Asset Management (UK) Limited. Intercompany accounts and transactions have been eliminated. Subsidiaries are fully consolidated from the date of acquisition, being the date on which GBL obtains control, and continue to be consolidated until the date that such control ceases. The annual financial statements have been prepared in accordance with U.S. GAAP for annual financial information and pursuant to the requirements for reporting on Form 10-K and Article 6 of Regulation S-X. In the opinion of management, all adjustments considered necessary for the fair presentation of consolidated financial statements for the years presented have been included.
Use of Estimates	Use of Estimates The preparation of the consolidated financial statements in conformity with U.S. 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.
Nature of Operations	Nature of Operations Gabelli Funds and GAMCO Asset are registered investment advisors under the Investment Advisers Act of 1940, as amended. G.distributors is a registered broker-dealer with the Securities and Exchange Commission (“SEC”) and is regulated by the Financial Industry Regulatory Authority (“FINRA”). Refer to Major Revenue-Generating Services and Revenue Recognition below for additional discussion of the Company’s business.
Cash and Cash Equivalents	Cash and Cash Equivalents and Short-term Investments in U.S. Treasury Bills Cash equivalents primarily consist of an affiliated money market fund (The Gabelli U.S. Treasury Money Market Fund) which is highly liquid. Government debt with maturities of three months or less at the time of purchase are also considered cash equivalents. Short-term investments in U.S. Treasury Bills consist of U.S. Treasury Bills with maturities exceeding three months at the time of purchase and are stated at amortized cost, which approximates fair value.
Currency Translation	Currency Translation Assets and liabilities of subsidiaries having non-U.S. dollar functional currencies are translated at exchange rates at the dates of the applicable consolidated statements of financial condition. Revenues and expenses of such subsidiaries are translated at the average exchange rates during the period. The gains or losses resulting from translating non-U.S. dollar functional currency into U.S. dollars are included in the consolidated statements of comprehensive income. Transactions in currencies other than the U.S. dollar, including the Company’s investments in U.K. Gilts, are measured on the transaction date in U.S. dollars. Changes in the expected cash flows caused by changes in exchange rates, measured at exchange rates at the dates of the applicable consolidated statements of financial condition, are included in the consolidated statements of income.
Investment in Securities	Investments in Securities Equity securities owned are recorded at fair value in the statements of financial condition, with any unrealized gains or losses reported in current period earnings in gain/(loss) from investments, net on the consolidated statements of income, in accordance with U.S. GAAP. Management determines the appropriate classification of debt securities at the time of purchase. Government debt with maturities of greater than three months at the time of purchase are considered investments in debt securities. Investments in debt securities are accounted for as either trading, available for sale (“AFS”), or held-to-maturity. The Company does not hold any investments in debt securities accounted for as trading or AFS. The Company’s investments in debt securities are classified as held-to-maturity, as the Company has the intent and ability to hold these securities until maturity, and represent fixed income securities recorded at amortized cost with any foreign currency remeasurement included in unrealized gains or losses in each respective period’s earnings. Discounts from and premiums to par value on held-to-maturity investments are accreted/amortized into interest income over the life of the respective security using the effective interest method. The amortized cost of debt investments represents the original cost adjusted for the accretion of discounts and amortization of premiums, if any. Held-to-maturity securities are evaluated for other than temporary impairment each reporting period and any impairment charges are recorded in gain/(loss) from investments, net on the consolidated statements of income. As of December 31, 2020 and 2019, there were no impairments on the Company’s investments in debt securities classified as held-to-maturity.
Major Revenue-Generating Services and Revenue Recognition	Major Revenue-Generating Services and Revenue Recognition The Company’s revenues are derived primarily from investment advisory and incentive fees and distribution fees. Investment advisory and incentive fees are directly influenced by the level and mix of assets under management (“AUM”), as fees are derived from a contractually-determined percentage of AUM for each account as well as incentive fees earned on certain accounts. Advisory fees from the open-end funds and closed-end funds (collectively, the “Funds”) and sub-advisory accounts are computed daily or weekly based on average net assets and amounts receivable are included in investment advisory fees receivable on the consolidated statements of financial condition. Advisory fees from Institutional and PWM accounts are generally computed quarterly based on account values as of the end of the preceding quarter, and amounts receivable are included in investment advisory fees receivable on the consolidated statements of financial condition. The Company derived approximately 90% and 89% of its total revenues from advisory fees, including incentive fees, for the years ended December 31, 2020 and 2019, respectively. These revenues vary depending upon the level of sales compared with redemptions, financial market conditions, performance, and the fee structure for the Fund or account. Revenues derived from the equity-oriented portfolios generally have higher advisory fee rates than fixed income portfolios. The Company receives incentive fees from certain Institutional and PWM accounts, which are based upon meeting or exceeding a specific benchmark index or indices. Incentive fees refer to fees earned when the return generated for the client exceeds the benchmark and can be earned even if the return to the client is negative as long as the return exceeds the benchmark. These fees are recognized, for each respective account, at the end of the stipulated contract period which is either quarterly or annually and varies by account. Receivables due for incentive fees earned are included in investment advisory fees receivable on the consolidated statements of financial condition. There were no incentive fees receivable as of December 31, 2020 and 2019. For The GDL Fund, there is an incentive fee earned as of the end of the calendar year which varies to the extent the total return of the fund is in excess of the ICE Bank of America Merrill Lynch 3 Month U.S. Treasury Bill Index total return. This fee is recognized at the end of the measurement period. Receivables due on incentive fees relating to The GDL Fund are included in investment advisory fees receivable on the consolidated statements of financial condition and were $0.1 million and $2.2 million as of December 31, 2020 and 2019, respectively. For the Gabelli Merger Plus⁺ Trust Plc, there is an incentive fee which is earned and recognized at the end of the measurement period, June 30^th and varies to the extent the total return of the fund is in excess of twice the rate of return of the 13 week Treasury Bills over the performance period. There were no incentive fees receivable as of December 31, 2020 or 2019. Advisory fees on certain of the closed-end preferred shares are earned at year-end if the total return to common shareholders of the closed-end fund for the calendar year exceeds the dividend rate of the preferred shares. These fees are recognized at the end of the measurement period, which is annually. Receivables due for advisory fees on closed-end preferred shares are included in investment advisory fees receivable on the consolidated statements of financial condition. There were $2.5 million and $5.8 million in advisory fees receivable on closed-end preferred shares as of December 31, 2020 and 2019. For the GAMCO Merger Arbitrage SICAV, there is an incentive fee earned as of the end of the calendar year equal to twenty percent of the gross return of the fund. This fee is recognized at the end of the measurement period, which is annually on a calendar year basis, or earlier if there is a redemption. Receivables due on incentive fees relating to the GAMCO Merger Arbitrage SICAV are included in investment advisory fees receivable on the consolidated statements of financial condition and were $5.6 million and $5.2 million as of December 31, 2020 and 2019, respectively. Distribution fees revenues are derived primarily from the distribution of Gabelli and GAMCO open-end Funds as well as the affiliated TETON Westwood and Keeley open-end funds advised by either a subsidiary of GBL (Gabelli Funds), a subsidiary of GGCP, Inc. (“GGCP”) (Teton), or a subsidiary of Teton (Keeley-Teton Advisors, Inc.). G.distributors distributes the open-end Funds pursuant to distribution agreements with each Fund. Under each distribution agreement with an open-end Fund, G.distributors offers and sells such open-end Fund shares on a continuous basis and pays all of the costs of marketing and selling the shares, including printing and mailing prospectuses and sales literature, advertising and maintaining sales and customer service teammates and sales and services fulfillment systems, and payments to the sponsors of third party distribution programs, financial intermediaries, and G.distributors’ sales teammates. G.distributors receives fees for such services pursuant to distribution plans adopted under provisions of Rule 12b-1 (“12b-1”) of the Investment Company Act of 1940, as amended (“Company Act”). G.distributors is the principal underwriter for funds distributed in multiple classes of shares which carry either a front-end or back-end sales charge. Under the distribution plans, the Class AAA shares of the open-end Funds (except The Gabelli U.S. Treasury Money Market Fund, Gabelli Capital Asset Fund, and The Gabelli ABC Fund) and the Class A and ADV shares of certain Funds pay G.distributors a distribution fee of 0.25% per year on the average daily net assets of the fund. Class C shares have a 12b-1 distribution plan with a distribution fee totaling 1.00%. Distribution fees from the open-end Funds are computed daily based on average net assets. The amounts receivable for distribution fees are included in receivables from affiliates on the consolidated statements of financial condition. Note 2 to the consolidated financial statements includes additional information on the Company’s revenue recognition policy.
Distribution Costs	Distribution Costs The Company incurs certain promotion and distribution costs, which are expensed as incurred, principally related to the sale of shares of Funds and after-market support services related to the closed-end Funds. Additionally, Gabelli Funds has agreed to reimburse expenses on certain funds beyond certain expense caps. The reimbursed expenses are presented on a gross basis in distribution costs in the consolidated statements of income.
Dividends and Interest Income and Interest Expense	Dividends and Interest Income and Interest Expense Dividends are recorded on the ex-dividend date. Interest income and interest expense are accrued as earned or incurred.
Depreciation and Amortization	Depreciation and Amortization Fixed assets other than leasehold improvements, with net book value of $2.5 million and $325 thousand at December 31, 2020 and 2019, respectively, which are included in other assets, are recorded at cost and depreciated using the straight-line method over their estimated useful lives from four to seven years. Accumulated depreciation was $2.9 million at both December 31, 2020 and 2019. Leasehold improvements, with net book value of $0.8 million and $1.1 million at December 31, 2020 and 2019, respectively, which are included in other assets, are recorded at cost and amortized using the straight-line method over their estimated useful lives or lease terms, whichever is shorter. The leased property under the finance lease is depreciated utilizing the straight-line method over the term of the lease, which expires on December 31, 2028. The finance lease was extended on June 11, 2014 to December 31, 2028 from December 31, 2023. For the years ended December 31, 2020 and 2019, depreciation and amortization were $0.9 million and $1.2 million, respectively. Depreciation and amortization is expected to be approximately $0.9 million annually over the next three years.
Goodwill and Identifiable Intangible Assets	Goodwill and Identifiable Intangible Assets Goodwill and identifiable intangible assets are initially measured as the excess of the cost of the acquired business over the sum of the amounts assigned to assets acquired less the liabilities assumed. Goodwill and identifiable intangible assets are tested for impairment at least annually as of November 30^th and whenever certain triggering events are met. In assessing the recoverability of goodwill and identifiable intangible assets, projections regarding estimated future cash flows and other factors are made to determine the fair value of the assets. If the book value exceeds the fair value of the assets, an impairment charge is recorded, corresponding to the amount by which the book value exceeds the fair value.
Income Taxes	Income Taxes GBL and its operating subsidiaries file a consolidated federal income tax return. Accordingly, the income tax provision represents the aggregate of the amounts provided for all companies. The Company operates in numerous states and countries through its subsidiaries and therefore must allocate income, expenses, and earnings to these taxing jurisdictions taking into account the various laws and regulations in each jurisdiction. Each year, the Company files tax returns in each jurisdiction and settles its tax liabilities, which may be subject to audit by the taxing authorities. Deferred tax assets and liabilities are recorded for temporary differences between the tax basis of assets and liabilities and the reported amounts on the consolidated statements of financial condition using the statutory tax rates in effect for the year when the reported amount of the asset or liability is recovered or settled, respectively. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in the results of operations in the period that includes the enactment date. In accordance with Accounting Standards Update (“ASU”) 2016-09, Improvements to Employee Share-Based Payment Accounting, excess tax benefits or tax deficiencies are recognized against income tax expenses. A valuation allowance is recorded to reduce the carrying values of deferred tax assets to the amount that is more likely than not to be realized. The calculation of our tax liabilities involves dealing with uncertainties in the application of complex tax laws and regulations in several jurisdictions. In accordance with Accounting Standards Codification (“ASC”) Topic 740, Income Taxes (“ASC 740”), a tax benefit from an uncertain tax position may be recognized when it is more likely than not that the position will be sustained upon examination, including resolutions of any related appeals or litigation processes, on the basis of the technical merits. We record a liability for unrecognized tax benefits in accordance with ASC 740 and adjust these liabilities when our judgment changes as a result of the evaluation of new information not previously available. Because of the complexity of some of these uncertainties, the ultimate resolution may differ from our current estimate of the liabilities for unrecognized tax benefits. These differences are reflected as increases or decreases in income tax expense in the period in which new information becomes available. The Company recognizes the accrual of interest on uncertain tax positions and penalties in income tax provision on the consolidated statements of income.
Fair Values of Financial Instruments	Fair Values of Financial Instruments All of the instruments within cash and cash equivalents, and investments in equity securities, at fair value, and securities sold, not yet purchased are measured at fair value. The Company’s assets and liabilities are categorized based upon a fair value hierarchy. See Note 4, Fair Value, for further details on the fair value hierarchy. Cash equivalents primarily consist of an affiliated money market fund which is invested solely in U.S. Treasuries and valued based on the net asset value of the fund. Government debt with maturities of three months or less at the time of purchase are also considered cash equivalents and are valued using unadjusted quoted market prices. Investments in securities are generally valued based on quoted prices from an exchange. To the extent these securities are actively traded, valuation adjustments are not applied, and they are categorized in Level 1 of the fair value hierarchy. Securities categorized in Level 2 investments are valued using other observable inputs. Nonpublic and infrequently traded investments are included in Level 3 of the fair value hierarchy because significant inputs to measure fair value are unobservable.
Earnings Per Share	Earnings Per Share Basic earnings per share is based on the weighted-average number of common shares outstanding during each period less unvested restricted stock. Diluted earnings per share is based on basic shares plus the incremental shares that would be issued upon the assumed exercise of in-the-money stock options and unvested restricted stock using the treasury stock method.
Management Fee	Management Fee Management fee expense is incentive-based and entirely variable compensation in the amount of 10% of the aggregate pre-tax profits before management fee which is paid to Mr. Mario J. Gabelli (“Mr. Gabelli”) or his designee for acting as CEO pursuant to his 2008 Employment Agreement so long as he is an executive of GBL and devotes the substantial majority of his working time to the business. In accordance with his 2008 Employment Agreement, he has allocated $0.8 million and $1.5 million of his management fee to certain other employees (“teammates”) of the Company in 2020 and 2019, respectively.
Stock Based Compensation	Stock Based Compensation The Company has granted equity awards, in the form of restricted stock awards (“RSAs”) to teammates and stock options to board members, which were recommended by the Company’s Chairman, who did not receive an RSA or option award, and approved by a committee of GBL’s board of directors (the “Board of Directors”) responsible for administering the awards (“Compensation Committee”). The Company’s stock-based compensation provided to teammates and board members is accounted for as an equity award based on fair value. The estimated fair value of RSAs is determined by using the closing price of Class A Common Stock (“Class A Stock”) on the grant date. The total expense, which is reduced by estimated forfeitures, is recognized over the vesting period for these awards which is 30% over three years from the date of grant and 70% over five years from the date of grant. The forfeiture rate is determined by reviewing historical forfeiture rates for previous stock-based compensation grants and is reviewed and updated quarterly, if necessary. During the vesting period, dividends to RSA holders are held for them until the RSA vesting dates and are forfeited if the grantee is no longer employed by the Company on the vesting dates. Dividends declared on these RSAs, less estimated forfeitures, are charged to retained earnings on the declaration date. The estimated fair value of option awards on the grant date is determined using the Black Scholes option-pricing model. This sophisticated model utilizes a number of assumptions in arriving at its results, including the estimated life of the option, the risk free interest rate at the date of grant, and the volatility of the underlying common stock. The effects of changing any of the assumptions or factors employed by the Black Scholes model may result in a significantly different valuation for the options. The total expense based on the grant date fair value, which is reduced by estimated forfeitures, is recognized over the vesting period for these awards which is 75% over three years from the date of grant and 25% over four years from date of grant. The forfeiture rate is determined by reviewing historical forfeiture rates for previous stock-based compensation grants and is reviewed and updated quarterly, if necessary.
Concentration of Credit Risk	Concentration of Credit Risk Financial instruments that potentially subject the Company to concentrations of credit risk consist primarily of cash and cash equivalents. The Company maintains cash and cash equivalents primarily in the Gabelli U.S. Treasury Money Market Fund, which invests in instruments issued by the U.S. government. The concentration of credit risk with respect to advisory fees receivable is generally limited due to the short payment terms extended to clients by the Company. In addition, the credit risk is further limited by virtue of the fact that no single advisory relationship provided over 10% of the total revenue of the Company during 2020 and 2019. All investments in securities are held at third party brokers or custodians.
Business Segment	Business Segment The Company operates in one business segment, the investment advisory and asset management business. The Company conducts its investment advisory business principally through Gabelli Funds (Funds) and GAMCO Asset (Institutional and PWM). The distribution of the open-end Funds and underwriting of those Funds is conducted through G.distributors.
Recent Accounting Developments	Recent Accounting Developments In February 2016, the Financial Accounting Standards Board (“FASB”) issued ASU 2016-02, Leases (Topic 842) (“ASU 2016-02”), which amends the guidance in U.S. GAAP for the accounting for leases with terms longer than 12 months. ASU 2016-02 requires a lessee to recognize assets and liabilities arising from these leases in the consolidated statement of financial position. It requires these leases to be recorded on the balance sheet as right-of-use assets and offsetting lease liability obligations. The guidance was effective for the Company on January 1, 2019 and the Company adopted this guidance on that date. The Company has elected the transition method allowed under ASU 2018-11, Leases (Topic 842): Targeted Improvements, which does not require restatement of comparative periods, but instead requires a cumulative adjustment to opening retained earnings at the January 1, 2019 adoption date. The Company has performed the analysis on the transition to this guidance and, as a result, recorded a $106 thousand reduction to retained earnings, a $650 thousand increase to other assets, and a $756 thousand increase to lease liability obligations. In January 2017, the FASB issued ASU 2017-04, Intangibles - Goodwill and Other (Topic 350) - Simplifying the Test for Goodwill Impairment (“ASU 2017-04”), which simplifies the process used to test for goodwill impairment by eliminating the requirement to calculate the implied fair value of goodwill, and instead any goodwill impairment will be the amount by which a reporting unit’s carrying value exceeds its fair value, not to exceed the carrying amount of goodwill. In November 2019, the FASB issued ASU 2019-10, Financial Instruments—Credit Losses (Topic 326), Derivatives and Hedging (Topic 815), Leases (Topic 842): Effective Dates (ASU 2019-10), which deferred the effective date of this guidance for smaller reporting companies for three years. This guidance will be effective for the Company on January 1, 2023 using a prospective transition method and early adoption is permitted. The Company is currently evaluating the potential effect of this new guidance on the Company’s consolidated financial statements. In June 2016, the FASB issued ASU 2016-13, Accounting for Financial Instruments - Credit Losses (Topic 326) (“ASU 2016-13”), which requires an organization to measure all expected credit losses for financial assets held at the reporting date based on historical experience, current conditions, and reasonable and supportable forecasts. Currently, U.S. GAAP requires an “incurred loss” methodology that delays recognition until it is probable a loss has been incurred. Under ASU 2016-13, the allowance for credit losses must be deducted from the amortized cost of the financial asset to present the net amount expected to be collected. The consolidated statement of income will reflect the measurement of credit losses for newly recognized financial assets as well as the expected increases or decreases of expected credit losses that have taken place during the period. In November 2019, the FASB issued ASU 2019-10, which deferred the effective date of this guidance for smaller reporting companies for three years. This guidance is effective for the Company on January 1, 2023 and requires a modified retrospective transition method, which will result in a cumulative-effect adjustment in retained earnings upon adoption. Early adoption is permitted. The Company is currently assessing the potential impact of this new guidance on the Company’s consolidated financial statements.

Significant Accounting Policies (Policies)

12 Months Ended

Dec. 31, 2020

Significant Accounting Policies [Abstract]

The consolidated financial statements have been prepared on the accrual basis of accounting in accordance with U.S. generally accepted accounting principles (“GAAP”). The consolidated financial statements include the accounts of the Company and its wholly-owned subsidiaries including: Gabelli Funds, GAMCO Asset, G.distributors, and GAMCO Asset Management (UK) Limited. Intercompany accounts and transactions have been eliminated. Subsidiaries are fully consolidated from the date of acquisition, being the date on which GBL obtains control, and continue to be consolidated until the date that such control ceases.

The annual financial statements have been prepared in accordance with U.S. GAAP for annual financial information and pursuant to the requirements for reporting on Form 10-K and Article 6 of Regulation S-X. In the opinion of management, all adjustments considered necessary for the fair presentation of consolidated financial statements for the years presented have been included.

Use of Estimates

The preparation of the consolidated financial statements in conformity with U.S. 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.

Nature of Operations

Gabelli Funds and GAMCO Asset are registered investment advisors under the Investment Advisers Act of 1940, as amended. G.distributors is a registered broker-dealer with the Securities and Exchange Commission (“SEC”) and is regulated by the Financial Industry Regulatory Authority (“FINRA”). Refer to Major Revenue-Generating Services and Revenue Recognition below for additional discussion of the Company’s business.

Cash and Cash Equivalents

Cash and Cash Equivalents and Short-term Investments in U.S. Treasury Bills

Cash equivalents primarily consist of an affiliated money market fund (The Gabelli U.S. Treasury Money Market Fund) which is highly liquid. Government debt with maturities of three months or less at the time of purchase are also considered cash equivalents. Short-term investments in U.S. Treasury Bills consist of U.S. Treasury Bills with maturities exceeding three months at the time of purchase and are stated at amortized cost, which approximates fair value.

Currency Translation

Assets and liabilities of subsidiaries having non-U.S. dollar functional currencies are translated at exchange rates at the dates of the applicable consolidated statements of financial condition. Revenues and expenses of such subsidiaries are translated at the average exchange rates during the period. The gains or losses resulting from translating non-U.S. dollar functional currency into U.S. dollars are included in the consolidated statements of comprehensive income.

Transactions in currencies other than the U.S. dollar, including the Company’s investments in U.K. Gilts, are measured on the transaction date in U.S. dollars. Changes in the expected cash flows caused by changes in exchange rates, measured at exchange rates at the dates of the applicable consolidated statements of financial condition, are included in the consolidated statements of income.

Investment in Securities

Investments in Securities

Equity securities owned are recorded at fair value in the statements of financial condition, with any unrealized gains or losses reported in current period earnings in gain/(loss) from investments, net on the consolidated statements of income, in accordance with U.S. GAAP.

Management determines the appropriate classification of debt securities at the time of purchase. Government debt with maturities of greater than three months at the time of purchase are considered investments in debt securities. Investments in debt securities are accounted for as either trading, available for sale (“AFS”), or held-to-maturity. The Company does not hold any investments in debt securities accounted for as trading or AFS. The Company’s investments in debt securities are classified as held-to-maturity, as the Company has the intent and ability to hold these securities until maturity, and represent fixed income securities recorded at amortized cost with any foreign currency remeasurement included in unrealized gains or losses in each respective period’s earnings. Discounts from and premiums to par value on held-to-maturity investments are accreted/amortized into interest income over the life of the respective security using the effective interest method. The amortized cost of debt investments represents the original cost adjusted for the accretion of discounts and amortization of premiums, if any. Held-to-maturity securities are evaluated for other than temporary impairment each reporting period and any impairment charges are recorded in gain/(loss) from investments, net on the consolidated statements of income. As of December 31, 2020 and 2019, there were no impairments on the Company’s investments in debt securities classified as held-to-maturity.

Major Revenue-Generating Services and Revenue Recognition

The Company’s revenues are derived primarily from investment advisory and incentive fees and distribution fees.

Investment advisory and incentive fees are directly influenced by the level and mix of assets under management (“AUM”), as fees are derived from a contractually-determined percentage of AUM for each account as well as incentive fees earned on certain accounts. Advisory fees from the open-end funds and closed-end funds (collectively, the “Funds”) and sub-advisory accounts are computed daily or weekly based on average net assets and amounts receivable are included in investment advisory fees receivable on the consolidated statements of financial condition. Advisory fees from Institutional and PWM accounts are generally computed quarterly based on account values as of the end of the preceding quarter, and amounts receivable are included in investment advisory fees receivable on the consolidated statements of financial condition. The Company derived approximately 90% and 89% of its total revenues from advisory fees, including incentive fees, for the years ended December 31, 2020 and 2019, respectively. These revenues vary depending upon the level of sales compared with redemptions, financial market conditions, performance, and the fee structure for the Fund or account. Revenues derived from the equity-oriented portfolios generally have higher advisory fee rates than fixed income portfolios.

The Company receives incentive fees from certain Institutional and PWM accounts, which are based upon meeting or exceeding a specific benchmark index or indices. Incentive fees refer to fees earned when the return generated for the client exceeds the benchmark and can be earned even if the return to the client is negative as long as the return exceeds the benchmark. These fees are recognized, for each respective account, at the end of the stipulated contract period which is either quarterly or annually and varies by account. Receivables due for incentive fees earned are included in investment advisory fees receivable on the consolidated statements of financial condition. There were no incentive fees receivable as of December 31, 2020 and 2019.

For The GDL Fund, there is an incentive fee earned as of the end of the calendar year which varies to the extent the total return of the fund is in excess of the ICE Bank of America Merrill Lynch 3 Month U.S. Treasury Bill Index total return. This fee is recognized at the end of the measurement period. Receivables due on incentive fees relating to The GDL Fund are included in investment advisory fees receivable on the consolidated statements of financial condition and were $0.1 million and $2.2 million as of December 31, 2020 and 2019, respectively.

For the Gabelli Merger Plus⁺ Trust Plc, there is an incentive fee which is earned and recognized at the end of the measurement period, June 30^th and varies to the extent the total return of the fund is in excess of twice the rate of return of the 13 week Treasury Bills over the performance period. There were no incentive fees receivable as of December 31, 2020 or 2019.

Advisory fees on certain of the closed-end preferred shares are earned at year-end if the total return to common shareholders of the closed-end fund for the calendar year exceeds the dividend rate of the preferred shares. These fees are recognized at the end of the measurement period, which is annually. Receivables due for advisory fees on closed-end preferred shares are included in investment advisory fees receivable on the consolidated statements of financial condition. There were $2.5 million and $5.8 million in advisory fees receivable on closed-end preferred shares as of December 31, 2020 and 2019.

For the GAMCO Merger Arbitrage SICAV, there is an incentive fee earned as of the end of the calendar year equal to twenty percent of the gross return of the fund. This fee is recognized at the end of the measurement period, which is annually on a calendar year basis, or earlier if there is a redemption. Receivables due on incentive fees relating to the GAMCO Merger Arbitrage SICAV are included in investment advisory fees receivable on the consolidated statements of financial condition and were $5.6 million and $5.2 million as of December 31, 2020 and 2019, respectively.

Distribution fees revenues are derived primarily from the distribution of Gabelli and GAMCO open-end Funds as well as the affiliated TETON Westwood and Keeley open-end funds advised by either a subsidiary of GBL (Gabelli Funds), a subsidiary of GGCP, Inc. (“GGCP”) (Teton), or a subsidiary of Teton (Keeley-Teton Advisors, Inc.). G.distributors distributes the open-end Funds pursuant to distribution agreements with each Fund. Under each distribution agreement with an open-end Fund, G.distributors offers and sells such open-end Fund shares on a continuous basis and pays all of the costs of marketing and selling the shares, including printing and mailing prospectuses and sales literature, advertising and maintaining sales and customer service teammates and sales and services fulfillment systems, and payments to the sponsors of third party distribution programs, financial intermediaries, and G.distributors’ sales teammates. G.distributors receives fees for such services pursuant to distribution plans adopted under provisions of Rule 12b-1 (“12b-1”) of the Investment Company Act of 1940, as amended (“Company Act”). G.distributors is the principal underwriter for funds distributed in multiple classes of shares which carry either a front-end or back-end sales charge.

Under the distribution plans, the Class AAA shares of the open-end Funds (except The Gabelli U.S. Treasury Money Market Fund, Gabelli Capital Asset Fund, and The Gabelli ABC Fund) and the Class A and ADV shares of certain Funds pay G.distributors a distribution fee of 0.25% per year on the average daily net assets of the fund. Class C shares have a 12b-1 distribution plan with a distribution fee totaling 1.00%.

Distribution fees from the open-end Funds are computed daily based on average net assets. The amounts receivable for distribution fees are included in receivables from affiliates on the consolidated statements of financial condition.

Note 2 to the consolidated financial statements includes additional information on the Company’s revenue recognition policy.

Distribution Costs

The Company incurs certain promotion and distribution costs, which are expensed as incurred, principally related to the sale of shares of Funds and after-market support services related to the closed-end Funds. Additionally, Gabelli Funds has agreed to reimburse expenses on certain funds beyond certain expense caps. The reimbursed expenses are presented on a gross basis in distribution costs in the consolidated statements of income.

Dividends and Interest Income and Interest Expense

Dividends are recorded on the ex-dividend date. Interest income and interest expense are accrued as earned or incurred.

Depreciation and Amortization

Fixed assets other than leasehold improvements, with net book value of $2.5 million and $325 thousand at December 31, 2020 and 2019, respectively, which are included in other assets, are recorded at cost and depreciated using the straight-line method over their estimated useful lives from four to seven years. Accumulated depreciation was $2.9 million at both December 31, 2020 and 2019. Leasehold improvements, with net book value of $0.8 million and $1.1 million at December 31, 2020 and 2019, respectively, which are included in other assets, are recorded at cost and amortized using the straight-line method over their estimated useful lives or lease terms, whichever is shorter. The leased property under the finance lease is depreciated utilizing the straight-line method over the term of the lease, which expires on December 31, 2028. The finance lease was extended on June 11, 2014 to December 31, 2028 from December 31, 2023. For the years ended December 31, 2020 and 2019, depreciation and amortization were $0.9 million and $1.2 million, respectively. Depreciation and amortization is expected to be approximately $0.9 million annually over the next three years.

Goodwill and Identifiable Intangible Assets

Goodwill and identifiable intangible assets are initially measured as the excess of the cost of the acquired business over the sum of the amounts assigned to assets acquired less the liabilities assumed. Goodwill and identifiable intangible assets are tested for impairment at least annually as of November 30^th and whenever certain triggering events are met. In assessing the recoverability of goodwill and identifiable intangible assets, projections regarding estimated future cash flows and other factors are made to determine the fair value of the assets. If the book value exceeds the fair value of the assets, an impairment charge is recorded, corresponding to the amount by which the book value exceeds the fair value.

Income Taxes

GBL and its operating subsidiaries file a consolidated federal income tax return. Accordingly, the income tax provision represents the aggregate of the amounts provided for all companies. The Company operates in numerous states and countries through its subsidiaries and therefore must allocate income, expenses, and earnings to these taxing jurisdictions taking into account the various laws and regulations in each jurisdiction. Each year, the Company files tax returns in each jurisdiction and settles its tax liabilities, which may be subject to audit by the taxing authorities. Deferred tax assets and liabilities are recorded for temporary differences between the tax basis of assets and liabilities and the reported amounts on the consolidated statements of financial condition using the statutory tax rates in effect for the year when the reported amount of the asset or liability is recovered or settled, respectively. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in the results of operations in the period that includes the enactment date. In accordance with Accounting Standards Update (“ASU”) 2016-09, Improvements to Employee Share-Based Payment Accounting, excess tax benefits or tax deficiencies are recognized against income tax expenses. A valuation allowance is recorded to reduce the carrying values of deferred tax assets to the amount that is more likely than not to be realized. The calculation of our tax liabilities involves dealing with uncertainties in the application of complex tax laws and regulations in several jurisdictions. In accordance with Accounting Standards Codification (“ASC”) Topic 740, Income Taxes (“ASC 740”), a tax benefit from an uncertain tax position may be recognized when it is more likely than not that the position will be sustained upon examination, including resolutions of any related appeals or litigation processes, on the basis of the technical merits. We record a liability for unrecognized tax benefits in accordance with ASC 740 and adjust these liabilities when our judgment changes as a result of the evaluation of new information not previously available. Because of the complexity of some of these uncertainties, the ultimate resolution may differ from our current estimate of the liabilities for unrecognized tax benefits. These differences are reflected as increases or decreases in income tax expense in the period in which new information becomes available. The Company recognizes the accrual of interest on uncertain tax positions and penalties in income tax provision on the consolidated statements of income.

Fair Values of Financial Instruments

All of the instruments within cash and cash equivalents, and investments in equity securities, at fair value, and securities sold, not yet purchased are measured at fair value.

The Company’s assets and liabilities are categorized based upon a fair value hierarchy. See Note 4, Fair Value, for further details on the fair value hierarchy.

Cash equivalents primarily consist of an affiliated money market fund which is invested solely in U.S. Treasuries and valued based on the net asset value of the fund. Government debt with maturities of three months or less at the time of purchase are also considered cash equivalents and are valued using unadjusted quoted market prices.

Investments in securities are generally valued based on quoted prices from an exchange. To the extent these securities are actively traded, valuation adjustments are not applied, and they are categorized in Level 1 of the fair value hierarchy. Securities categorized in Level 2 investments are valued using other observable inputs. Nonpublic and infrequently traded investments are included in Level 3 of the fair value hierarchy because significant inputs to measure fair value are unobservable.

Earnings Per Share

Basic earnings per share is based on the weighted-average number of common shares outstanding during each period less unvested restricted stock. Diluted earnings per share is based on basic shares plus the incremental shares that would be issued upon the assumed exercise of in-the-money stock options and unvested restricted stock using the treasury stock method.

Management Fee

Management fee expense is incentive-based and entirely variable compensation in the amount of 10% of the aggregate pre-tax profits before management fee which is paid to Mr. Mario J. Gabelli (“Mr. Gabelli”) or his designee for acting as CEO pursuant to his 2008 Employment Agreement so long as he is an executive of GBL and devotes the substantial majority of his working time to the business. In accordance with his 2008 Employment Agreement, he has allocated $0.8 million and $1.5 million of his management fee to certain other employees (“teammates”) of the Company in 2020 and 2019, respectively.

Stock Based Compensation

The Company has granted equity awards, in the form of restricted stock awards (“RSAs”) to teammates and stock options to board members, which were recommended by the Company’s Chairman, who did not receive an RSA or option award, and approved by a committee of GBL’s board of directors (the “Board of Directors”) responsible for administering the awards (“Compensation Committee”). The Company’s stock-based compensation provided to teammates and board members is accounted for as an equity award based on fair value.

The estimated fair value of RSAs is determined by using the closing price of Class A Common Stock (“Class A Stock”) on the grant date. The total expense, which is reduced by estimated forfeitures, is recognized over the vesting period for these awards which is 30% over three years from the date of grant and 70% over five years from the date of grant. The forfeiture rate is determined by reviewing historical forfeiture rates for previous stock-based compensation grants and is reviewed and updated quarterly, if necessary. During the vesting period, dividends to RSA holders are held for them until the RSA vesting dates and are forfeited if the grantee is no longer employed by the Company on the vesting dates. Dividends declared on these RSAs, less estimated forfeitures, are charged to retained earnings on the declaration date.

The estimated fair value of option awards on the grant date is determined using the Black Scholes option-pricing model. This sophisticated model utilizes a number of assumptions in arriving at its results, including the estimated life of the option, the risk free interest rate at the date of grant, and the volatility of the underlying common stock. The effects of changing any of the assumptions or factors employed by the Black Scholes model may result in a significantly different valuation for the options. The total expense based on the grant date fair value, which is reduced by estimated forfeitures, is recognized over the vesting period for these awards which is 75% over three years from the date of grant and 25% over four years from date of grant. The forfeiture rate is determined by reviewing historical forfeiture rates for previous stock-based compensation grants and is reviewed and updated quarterly, if necessary.

Concentration of Credit Risk

Financial instruments that potentially subject the Company to concentrations of credit risk consist primarily of cash and cash equivalents. The Company maintains cash and cash equivalents primarily in the Gabelli U.S. Treasury Money Market Fund, which invests in instruments issued by the U.S. government. The concentration of credit risk with respect to advisory fees receivable is generally limited due to the short payment terms extended to clients by the Company. In addition, the credit risk is further limited by virtue of the fact that no single advisory relationship provided over 10% of the total revenue of the Company during 2020 and 2019. All investments in securities are held at third party brokers or custodians.

Business Segment

The Company operates in one business segment, the investment advisory and asset management business. The Company conducts its investment advisory business principally through Gabelli Funds (Funds) and GAMCO Asset (Institutional and PWM). The distribution of the open-end Funds and underwriting of those Funds is conducted through G.distributors.

Recent Accounting Developments

In February 2016, the Financial Accounting Standards Board (“FASB”) issued ASU 2016-02, Leases (Topic 842) (“ASU 2016-02”), which amends the guidance in U.S. GAAP for the accounting for leases with terms longer than 12 months. ASU 2016-02 requires a lessee to recognize assets and liabilities arising from these leases in the consolidated statement of financial position. It requires these leases to be recorded on the balance sheet as right-of-use assets and offsetting lease liability obligations. The guidance was effective for the Company on January 1, 2019 and the Company adopted this guidance on that date. The Company has elected the transition method allowed under ASU 2018-11, Leases (Topic 842): Targeted Improvements, which does not require restatement of comparative periods, but instead requires a cumulative adjustment to opening retained earnings at the January 1, 2019 adoption date. The Company has performed the analysis on the transition to this guidance and, as a result, recorded a $106 thousand reduction to retained earnings, a $650 thousand increase to other assets, and a $756 thousand increase to lease liability obligations.

In January 2017, the FASB issued ASU 2017-04, Intangibles - Goodwill and Other (Topic 350) - Simplifying the Test for Goodwill Impairment (“ASU 2017-04”), which simplifies the process used to test for goodwill impairment by eliminating the requirement to calculate the implied fair value of goodwill, and instead any goodwill impairment will be the amount by which a reporting unit’s carrying value exceeds its fair value, not to exceed the carrying amount of goodwill. In November 2019, the FASB issued ASU 2019-10, Financial Instruments—Credit Losses (Topic 326), Derivatives and Hedging (Topic 815), Leases (Topic 842): Effective Dates (ASU 2019-10), which deferred the effective date of this guidance for smaller reporting companies for three years. This guidance will be effective for the Company on January 1, 2023 using a prospective transition method and early adoption is permitted. The Company is currently evaluating the potential effect of this new guidance on the Company’s consolidated financial statements.

In June 2016, the FASB issued ASU 2016-13, Accounting for Financial Instruments - Credit Losses (Topic 326) (“ASU 2016-13”), which requires an organization to measure all expected credit losses for financial assets held at the reporting date based on historical experience, current conditions, and reasonable and supportable forecasts. Currently, U.S. GAAP requires an “incurred loss” methodology that delays recognition until it is probable a loss has been incurred. Under ASU 2016-13, the allowance for credit losses must be deducted from the amortized cost of the financial asset to present the net amount expected to be collected. The consolidated statement of income will reflect the measurement of credit losses for newly recognized financial assets as well as the expected increases or decreases of expected credit losses that have taken place during the period. In November 2019, the FASB issued ASU 2019-10, which deferred the effective date of this guidance for smaller reporting companies for three years. This guidance is effective for the Company on January 1, 2023 and requires a modified retrospective transition method, which will result in a cumulative-effect adjustment in retained earnings upon adoption. Early adoption is permitted. The Company is currently assessing the potential impact of this new guidance on the Company’s consolidated financial statements.