Associated Capital (AC) 10-Q 7 Nov 17 2017 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2017	Oct. 31, 2017
Entity Information [Line Items]
Entity Registrant Name	Associated Capital Group, Inc.
Entity Central Index Key	1,642,122
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Accelerated Filer
Document Fiscal Year Focus	2,017
Document Fiscal Period Focus	Q3
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2017
Class A [Member]
Entity Information [Line Items]
Entity Common Stock, Shares Outstanding		4,505,966
Class B [Member]
Entity Information [Line Items]
Entity Common Stock, Shares Outstanding		19,195,649

CONDENSED CONSOLIDATED STATEMEN

CONDENSED CONSOLIDATED STATEMENTS OF FINANCIAL CONDITION UNAUDITED - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016	Sep. 30, 2016
ASSETS
Cash and cash equivalents	$ 242,302	$ 314,093	$ 402,403
Investments in securities	293,872	207,096	106,472
Investment in GBL stock (4,393,055 shares)	130,737	135,701	125,070
Investments in affiliated registered investment companies	143,065	131,645	126,222
Investments in partnerships	141,094	129,398	128,198
Receivable from brokers	15,753	12,588	19,807
Investment advisory fees receivable	1,433	9,784	1,932
Receivable from affiliates	3,174	1,523	7,917
Goodwill	3,422	3,422	3,422
Other assets	4,667	7,353	3,368
Total assets	979,519	952,603	924,811
LIABILITIES, REDEEMABLE NONCONTROLLING INTERESTS AND EQUITY
Payable to brokers	13,421	2,396	1,549
Income taxes payable and deferred tax liabilities	4,346	6,978	2,014
Compensation payable	9,439	17,676	8,499
Securities sold, not yet purchased	9,059	9,984	4,215
Payable to affiliates	436	1,455	331
Accrued expenses and other liabilities	2,491	35,862	6,135
Total liabilities	39,192	74,351	22,743
Redeemable noncontrolling interests	42,119	4,230	3,999
Equity:
Preferred stock, $.001 par value; 10,000,000 shares authorized; none issued and outstanding	0	0	0
Additional paid-in capital	1,009,852	1,007,027	1,006,502
Retained earnings	364	7,327	6,102
GBL 4% PIK Note	(70,000)	(100,000)	(100,000)
Accumulated comprehensive income	15,518	1,317	(7,633)
Treasury stock, at cost (1,805,945, 1,339,932, and 237,255 shares, respectively)	(57,551)	(41,674)	(6,927)
Total Associated Capital Group, Inc. stockholders' equity	898,208	874,022	898,069
Total liabilities and equity	979,519	952,603	924,811
Class A [Member]
Equity:
Common stock	6	6	6
Class B [Member]
Equity:
Common stock	$ 19	$ 19	$ 19

CONDENSED CONSOLIDATED STATEME3

CONDENSED CONSOLIDATED STATEMENTS OF FINANCIAL CONDITION UNAUDITED (Parenthetical) - $ / shares	Sep. 30, 2017	Dec. 31, 2016	Sep. 30, 2016
ASSETS
Investment in GBL stock, shares (in shares)	4,393,055	4,393,055	4,393,055
Equity:
Preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001	$ 0.001
Preferred stock, shares authorized (in shares)	10,000,000	10,000,000	10,000,000
Preferred stock, shares issued (in shares)	0	0	0
Preferred stock, shares outstanding (in shares)	0	0	0
Common stock, shares outstanding (in shares)	23,800,000	24,300,000	25,400,000
Treasury stock, shares (in shares)	1,805,945	1,339,932	237,255
GBL 4% PIK Note [Member]
Equity:
Debt instrument, interest rate	4.00%
Class A [Member]
Equity:
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	100,000,000	100,000,000	100,000,000
Common stock, shares issued (in shares)	6,396,523	6,398,580	6,401,530
Common stock, shares outstanding (in shares)	4,590,578	5,058,648	6,164,275
Class B [Member]
Equity:
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	100,000,000	100,000,000	100,000,000
Common stock, shares issued (in shares)	19,196,792	19,196,792	19,196,792
Common stock, shares outstanding (in shares)	19,195,649	19,196,792	19,196,792

CONDENSED CONSOLIDATED STATEME4

CONDENSED CONSOLIDATED STATEMENTS OF INCOME UNAUDITED - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Revenues
Investment advisory and incentive fees	$ 2,587	$ 2,294	$ 7,318	$ 6,586
Institutional research services	2,584	2,992	7,917	8,102
Other	77	165	95	244
Total revenues	5,248	5,451	15,330	14,932
Expenses
Compensation	6,492	6,415	19,696	18,168
Management fee	0	641	0	1,066
Stock based compensation	1,862	727	5,226	2,015
Other operating expenses	3,006	2,165	7,305	6,047
Total expenses	11,360	9,948	32,227	27,296
Operating loss	(6,112)	(4,497)	(16,897)	(12,364)
Other income (expense)
Net gain/(loss) from investments	5,234	7,566	(1,018)	12,770
Interest and dividend income	2,347	2,833	7,295	9,762
Interest expense	(69)	(66)	(210)	(554)
Shareholder-designated contribution	0	0	(4,895)	0
Total other income, net	7,512	10,333	1,172	21,978
Income/(loss) before income taxes	1,400	5,836	(15,725)	9,614
Income tax provision	67	1,807	(8,667)	2,773
Net income/(loss)	1,333	4,029	(7,058)	6,841
Net income/(loss) attributable to noncontrolling interests	(186)	70	(95)	270
Net income/(loss) attributable to Associated Capital Group, Inc.'s shareholders	$ 1,519	$ 3,959	$ (6,963)	$ 6,571
Net income/(loss) attributable to Associated Capital Group, Inc.'s shareholders per share:
Basic (in dollars per share)	$ 0.06	$ 0.16	$ (0.29)	$ 0.26
Diluted (in dollars per share)	$ 0.06	$ 0.16	$ (0.29)	$ 0.26
Weighted average shares outstanding:
Basic (in shares)	23,841	24,918	23,826	24,879
Diluted (in shares)	23,841	25,219	23,826	25,194
Dividends declared (in dollars per share)	$ 0	$ 0	$ 0.10	$ 0.10

CONDENSED CONSOLIDATED STATEME5

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME UNAUDITED - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME UNAUDITED [Abstract]
Net income/(loss)		$ 1,333	$ 4,029	$ (7,058)	$ 6,841
Other comprehensive income/(loss), net of tax:
Net unrealized gains/(losses) on securities available for sale	[1]	1,686	(9,336)	14,201	(4,812)
Other comprehensive income/(loss)		1,686	(9,336)	14,201	(4,812)
Comprehensive income/(loss)		3,019	(5,307)	7,143	2,029
Less: Comprehensive income/(loss) attributable to noncontrolling interests		(186)	70	(95)	1,234
Comprehensive income/(loss) attributable to Associated Capital Group, Inc.		$ 3,205	$ (5,377)	$ 7,238	$ 795
[1]	Net of income tax expense/(benefit) of $948, $(5,251), $7,988, and $(3,751), respectively.

CONDENSED CONSOLIDATED STATEME6

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME UNAUDITED (Parenthetical) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Other comprehensive income/(loss), net of tax:
Net unrealized gains/(losses) on securities available for sale, income tax expense/(benefit)	$ 948	$ (5,251)	$ 7,988	$ (3,751)

CONDENSED CONSOLIDATED STATEME7

CONDENSED CONSOLIDATED STATEMENTS OF EQUITY UNAUDITED - USD ($) $ in Thousands	Noncontrolling Interests [Member]	Common Stock [Member]	Retained Earnings [Member]	Additional Paid-in Capital [Member]	GBL 4% PIK Note [Member]	Accumulated Comprehensive Income [Member]	Treasury Stock [Member]	Total	Redeemable Noncontrolling Interests [Member]
Balance at Dec. 31, 2015	$ 2,353	$ 25	$ 2,072	$ 999,000	$ (250,000)	$ (1,857)	$ (44)	$ 751,549	$ 5,738
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Redemptions of noncontrolling interests	0	0	0	0	0	0	0	0	(244)
Deconsolidation of an offshore fund	0	0	0	0	0	0	0	0	(1,811)
Net income (loss)	(46)	0	6,571	0	0	0	0	6,525	316
Net unrealized gains (losses) on securities available for sale, net of income tax expense (benefit)	964	0	0	0	0	(5,744)	0	(4,780)	0
Amounts reclassified from accumulated other comprehensive income, net of income tax (expense)	0	0	0	0	0	(32)	0	(32)	0
Increase to paid in capital for the excess of actual tax benefit over recorded RSA tax benefit	0	0	0	625	0	0	0	625	0
Noncontrolling minority interest	(3,271)	0	0	4,862	0	0	0	1,591	0
Dividends declared ($0.10 per share)	0	0	(2,541)	0	0	0	0	(2,541)	0
Stock based compensation expense	0	0	0	2,015	0	0	0	2,015	0
Purchase of treasury stock	0	0	0	0	0	0	(6,883)	(6,883)	0
Proceeds from payment of GBL 4% PIK Note	0	0	0	0	150,000	0	0	150,000	0
Balance at Sep. 30, 2016	$ 0	25	6,102	1,006,502	(100,000)	(7,633)	(6,927)	898,069	3,999
Balance at Dec. 31, 2016		25	7,327	1,007,027	(100,000)	1,317	(41,674)	874,022	4,230
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Redemptions of noncontrolling interests		0	0	0	0	0	0	0	(236)
Contributions from noncontrolling interests		0	0	0	0	0	0	0	38,220
Net income (loss)		0	(6,963)	0	0	0	0	(6,963)	(95)
Net unrealized gains (losses) on securities available for sale, net of income tax expense (benefit)		0	0	0	0	2,064	0	2,064	0
Amounts reclassified from accumulated other comprehensive income, net of income tax (expense)		0	0	0	0	12,137	0	12,137	0
Dividends declared ($0.10 per share)		0	0	(2,401)	0	0	0	(2,401)	0
Stock based compensation expense		0	0	5,226	0	0	0	5,226	0
Purchase of treasury stock		0	0	0	0	0	(15,877)	(15,877)	0
Proceeds from payment of GBL 4% PIK Note		0	0	0	30,000	0	0	30,000	0
Balance at Sep. 30, 2017		$ 25	$ 364	$ 1,009,852	$ (70,000)	$ 15,518	$ (57,551)	$ 898,208	$ 42,119

CONDENSED CONSOLIDATED STATEME8

CONDENSED CONSOLIDATED STATEMENTS OF EQUITY UNAUDITED (Parenthetical) $ in Thousands	9 Months Ended
	Sep. 30, 2017USD ($)$ / shares	Sep. 30, 2016USD ($)$ / shares
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net unrealized gains (losses) on securities available for sale, income tax expense (benefit)	$ 1,161	$ (2,689)
Amounts reclassified from accumulated other comprehensive income, income tax (expense)	$ 6,827	$ (18)
Dividend declared (in dollars per share) | $ / shares	$ 0.10	$ 0.10
GBL 4% PIK Note [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Debt instrument, interest rate	4.00%

CONDENSED CONSOLIDATED STATEME9

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS UNAUDITED - USD ($)	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016
Operating activities
Net income/(loss)	$ (7,058,000)	$ 6,841,000
Adjustments to reconcile net income/(loss) to net cash provided by operating activities:
Equity in net gains from partnerships	(6,325,000)	(7,203,000)
Depreciation and amortization	12,000	13,000
Stock based compensation expense	5,226,000	2,015,000
Other-than-temporary loss on available for sale securities	19,131,000	298,000
Donated securities	2,627,000	0
Net gains on sales of available for sale securities	(167,000)	(348,000)
(Increase) decrease in assets:
Investments in trading securities	(91,584,000)	82,670,000
Investments in partnerships:
Contributions to partnerships	(16,928,000)	(30,217,000)
Distributions from partnerships	11,557,000	14,268,000
Receivable from affiliates	(1,651,000)	(460,000)
Receivable from brokers	(3,165,000)	36,006,000
Investment advisory fees receivable	8,351,000	2,946,000
Other assets	2,672,000	(1,478,000)
Increase (decrease) in liabilities:
Payable to brokers	11,025,000	(49,078,000)
Income taxes payable and deferred tax liabilities	(10,619,000)	(323,000)
Payable to affiliates	(1,019,000)	331,000
Compensation payable	(8,237,000)	(2,426,000)
Mandatorily redeemable noncontrolling interests	0	292,000
Accrued expenses and other liabilities	(33,368,000)	4,693,000
Total adjustments	(112,462,000)	51,999,000
Net cash (used in) provided by operating activities	(119,520,000)	58,840,000
Investing activities
Purchases of available for sale securities	(3,583,000)	(4,111,000)
Proceeds from sales of available for sale securities	271,000	803,000
Return of capital on available for sale securities	1,337,000	754,000
Net cash provided by investing activities	(1,975,000)	(2,554,000)
Financing activities
Contributions from redeemable noncontrolling interests	38,220,000	0
Redemptions of redeemable noncontrolling interests	(236,000)	(244,000)
Dividends paid	(2,403,000)	(2,504,000)
Purchase of treasury stock	(15,877,000)	(6,883,000)
Proceeds from payment of GBL 4% PIK Note	30,000,000	150,000,000
Net cash provided by financing activities	49,704,000	140,369,000
Net increase (decrease) in cash and cash equivalents	(71,791,000)	196,655,000
Cash and cash equivalents at beginning of period	314,093,000	205,750,000
Decrease in cash from deconsolidation	0	(2,000)
Cash and cash equivalents at end of period	242,302,000	402,403,000
Supplemental disclosures of cash flow information:
Cash paid for interest	210,000	262,000
Cash paid for taxes	$ 2,077,000	$ 2,989,000

CONDENSED CONSOLIDATED STATEM10

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS UNAUDITED (Parenthetical) $ in Thousands	Jul. 19, 2017USD ($)Fund	Jan. 01, 2016USD ($)	Sep. 30, 2017USD ($)	Sep. 30, 2016USD ($)shares
Non-cash activity:
Dividends accrued on restricted stock awards			$ 8	$ 50
Number of AC shares exchanged (in shares) | shares				163,428
Decrease in cash and cash equivalents from deconsolidation		$ (1)
Decrease in net assets from deconsolidation		(104)
Decrease in redeemable noncontrolling interests from deconsolidation		(105)		$ 0
Increase in other net assets from consolidation	$ 99,276
Increase in redeemable noncontrolling interest from consolidation	$ 37,901
Offshore Funds [Member]
Non-cash activity:
Number of funds consolidated | Fund	1
Gabelli Securities, Inc. [Member]
Non-cash activity:
Minority ownership interest acquired				6.10%
Accounting Standards Update 2015-02 [Member]
Non-cash activity:
Decrease in cash and cash equivalents from deconsolidation		(1)
Decrease in net assets from deconsolidation		(1,705)
Decrease in redeemable noncontrolling interests from deconsolidation		$ (1,706)
GBL 4% PIK Note [Member]
Financing activities
Debt instrument, interest rate			4.00%

Basis of Presentation and Signi

Basis of Presentation and Significant Accounting Policies	9 Months Ended
	Sep. 30, 2017
Basis of Presentation and Significant Accounting Policies [Abstract]
Basis of Presentation and Significant Accounting Policies	A. Basis of Presentation and Significant Accounting Policies Unless we have indicated otherwise, or the context otherwise requires, references in this report to “Associated Capital Group, Inc.,” “AC Group,” “the Company,” “AC,” “we,” “us” and “our” or similar terms are to Associated Capital Group, Inc., its predecessors and its subsidiaries. The Spin-off and Related Transactions We are a Delaware corporation that provides alternative investment management, institutional research and underwriting services. In addition, we derive investment income/(loss) from proprietary trading of cash and other assets awaiting deployment in our operating businesses. On November 30, 2015, GAMCO Investors, Inc. (“GAMCO” or “GBL”) distributed all the outstanding shares of each class of AC common stock on a pro rata one-for-one basis to the holders of each class of GAMCO’s common stock (the “Spin-off”). We conduct our investment management business through Gabelli & Company Investment Advisers, Inc. (“GCIA” f/k/a Gabelli Securities, Inc.). GCIA and its wholly-owned subsidiary, Gabelli & Partners, LLC (“Gabelli & Partners”), collectively serve as general partners or investment managers to investment funds including limited partnerships and offshore companies (collectively, “Investment Partnerships”), and separate accounts. We primarily manage assets in equity event-driven value strategies, across a range of risk and event arbitrage portfolios. The business earns management and incentive fees from its advisory assets. Management fees are largely based on a percentage of assets under management. Incentive fees are based on the percentage of the investment returns of certain clients’ portfolios. GCIA is an investment adviser registered with the Securities and Exchange Commission under the Investment Advisers Act of 1940, as amended. We provide our institutional research and underwriting services through G.research, LLC (“G.research”) doing business as “Gabelli & Company”, an indirect wholly-owned subsidiary of the Company. G.research is a broker-dealer registered under the Securities Exchange Act of 1934, as amended (the “Exchange Act”) and is regulated by the Financial Industry Regulatory Authority (“FINRA”). G.research's revenues are derived primarily from institutional research services. In connection with the Spin-off, GAMCO issued a promissory note (the “GAMCO Note”) to AC Group in the original principal amount of $250 million used to partially capitalize the Company. The GAMCO Note bears interest at 4% per annum and has a maturity date of November 30, 2020 with respect to its original principal amount. Interest on the GAMCO Note will accrue from the most recent date for which interest has been paid. Prior to November 30, 2019, at the election of GAMCO, payment of interest on the GAMCO Note may, in lieu of being paid in cash, be paid, in whole or in part, in kind (a “PIK Amount”). GAMCO will repay all PIK Amounts added to the outstanding principal amount of the GAMCO Note, in cash, on the fifth anniversary of the date on which each such PIK Amount was added to the outstanding principal amount of the GAMCO Note. GAMCO may prepay the GAMCO Note prior to maturity without penalty. AC has received principal repayments totaling $180 million on the GAMCO Note, of which $10 million was received during the three months ended September 30, 2017 leaving an outstanding principal balance of $70 million. After application of the principal payments, $20 million and $50 million are due on November 30, 2019 and November 30, 2020, respectively. In addition, GCIA GCIA the GCIA Note is now an intercompany obligation within the AC Group. Basis of Presentation The unaudited interim condensed consolidated financial statements of AC Group included herein have been prepared in conformity with accounting principles generally accepted in the United States of America (“GAAP”) for interim financial information and with the instructions to Form 10-Q and Rule 10-01 of Regulation S-X. Accordingly, they do not include all the information and footnotes required by GAAP in the United States for complete financial statements. In the opinion of management, the unaudited interim condensed consolidated financial statements reflect all adjustments, which are of a normal recurring nature, necessary for a fair presentation of financial position, results of operations and cash flows of the Company for the interim periods presented and are not necessarily indicative of a full year’s results. The interim condensed consolidated financial statements include the accounts of AC Group and its subsidiaries. Intercompany accounts and transactions are eliminated. These interim condensed consolidated financial statements should be read in conjunction with our audited consolidated financial statements included in our Annual Report on Form 10-K for the year ended December 31, 2016. Use of Estimates The preparation of the condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported on the condensed consolidated financial statements and accompanying notes. Actual results could differ from those estimates. Reclassification The Company has reclassified certain prior-period amounts to conform to the current-period presentation. For presentation of 2017 results, the Company reported revenue from its research services agreement with GAMCO in “Institutional Research Services Revenue” instead of “Other Revenue”. The reclassification did not impact revenue, operating expenses, operating income, net income, or equity. Recent Accounting Developments On May 10, 2017, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2017-09, which amends the scope of modification accounting for share-based payment arrangements. The ASU provides guidance on the types of changes to the terms or conditions of share-based payment awards to which an entity would be required to apply modification accounting under ASC 718. Specifically, an entity would not apply modification accounting if the fair value, vesting conditions, and classification of the awards are the same immediately before and after the modification. For all entities, the ASU is effective for annual reporting periods, including interim periods within those annual reporting periods, beginning after December 15, 2017. Early adoption is permitted, including adoption in any interim period. This ASU, which we did not early adopt, nonetheless would not have impacted the accounting for the acceleration of vesting of restricted stock awards (“RSAs”) during the nine months ended September 30, 2017. In March 2016, the FASB issued ASU 2016-09, which simplifies several aspects of the accounting for employee share-based payment transactions for both public and nonpublic entities, including the accounting for income taxes, forfeitures, and statutory tax withholding requirements, as well as classification in the statement of cash flows. For public companies, the ASU is effective for annual reporting periods beginning after December 15, 2016, including interim periods within those annual reporting periods. The Company adopted this ASU effective January 1, 2017 and applied this standard during the nine months ended September 30, 2017 in relation to an acceleration of vesting of RSAs during the period. In May 2014, the FASB issued ASU No. 2014-09, Revenue from Contracts with Customers, which supersedes the revenue recognition requirements in the Accounting Standards Codification (“Codification”) Topic 605, Revenue Recognition, and most industry-specific guidance throughout the industry topics of the Codification. The core principle of the new ASU No. 2014-09 is for companies to recognize revenue from the transfer of goods or services to customers in amounts that reflect the consideration to which the company expects to be entitled in exchange for those goods or services. The new standard provides a five-step approach to be applied to all contracts with customers and also requires expanded disclosures about revenue recognition. In March 2016, the FASB issued revised guidance which clarifies the guidance related to (a) determining the appropriate unit of account under the revenue standard’s principal versus agent guidance and (b) applying the indicators of whether an entity is a principal or an agent in accordance with the revenue standard’s control principle. In April 2016, the FASB issued an amendment to provide more detailed guidance including additional implementation guidance and examples related to (a) identifying performance obligations and (b) licenses of intellectual property. In May 2016, the FASB amended the standard to clarify the guidance on assessing collectability, presenting sales taxes, measuring noncash consideration, and certain transition matters. This new guidance will be effective for the Company's first quarter of 2018 and requires either a full retrospective or a modified retrospective approach to adoption. The Company’s implementation analysis is ongoing; however, it does not expect the adoption of the guidance to have a significant effect on the timing of the recognition of revenue. The Company is currently evaluating performance obligations and the related transaction costs. The Company is also reviewing and preparing for the enhanced disclosure requirements of the standard. The overall effect upon adoption may change based on further analysis and implementation efforts. The Company has not yet determined which transition method it will use. In January 2016, the FASB issued ASU 2016-01, which amends the guidance in GAAP on the classification and measurement of financial instruments. Although the ASU retains many current requirements, it significantly revises an entity’s accounting related to (a) the classification and measurement of investments in equity securities and (b) the presentation of certain fair value changes for financial liabilities measured at fair value. The ASU also amends certain disclosure requirements associated with the fair value of financial instruments. For public companies, the new standard is effective for fiscal years and interim periods within those fiscal years beginning after December 15, 2017. To adopt the amendments, entities will be required to make a cumulative-effect adjustment to beginning retained earnings as of the beginning of the fiscal year in which the guidance is effective. The Company is currently evaluating this guidance and the impact it will have on its condensed consolidated financial statements. In August 2016, the FASB issued ASU 2016-15, which adds and clarifies guidance on the classification of certain cash receipts and payments in the consolidated statements of cash flows. For public companies, the ASU is effective for annual reporting periods beginning after December 15, 2017, including interim periods within those annual reporting periods. Early adoption is permitted. The Company is currently evaluating this guidance and the impact it will have on its condensed consolidated financial statements. In January 2017, the FASB issued ASU 2017-04 to simplify the process used to test for goodwill. Under the new standard, if “the carrying amount of a reporting unit exceeds its fair value, an impairment loss shall be recognized in an amount equal to that excess, limited to the total amount of goodwill allocated to that reporting unit.” For public companies, the ASU is effective for annual and any interim impairment tests for periods beginning after December 15, 2019. Early adoption is permitted for impairment tests that occur after January 1, 2017. The Company is currently evaluating this guidance and the impact it will have on its condensed consolidated financial statements.

Investment in Securities

Investment in Securities	9 Months Ended
	Sep. 30, 2017
Investment in Securities [Abstract]
Investment in Securities	B. Investment in Securities Management determines the appropriate classification of debt and equity securities at the time of purchase and reevaluates such designation as of the date of each consolidated statement of financial condition. Investments in United States Treasury Bills and Notes with maturities of greater than three months at the time of purchase are classified as investments in securities, and those with maturities of three months or less at the time of purchase are classified as cash equivalents. The portion of investments in securities held for resale in anticipation of short-term market movements are classified as trading securities. Trading securities are stated at fair value, with any unrealized gains or losses reported in current period earnings. Available for sale (“AFS”) investments are stated at fair value, with any unrealized gains or losses, net of taxes, reported as a component of equity except for losses deemed to be other-than- temporary (“OTT”) which are recorded as realized losses in the condensed consolidated statements of income. In addition, realized gains and losses from AFS securities are reclassified from equity to current period income. Investments in securities, including GBL stock, at September 30, 2017, December 31, 2016 and September 30, 2016 consisted of the following: September 30, 2017 December 31, 2016 September 30, 2016 Cost Fair Value Cost Fair Value Cost Fair Value (In thousands) Trading securities: Government obligations $ 115,897 $ 116,152 $ 119,755 $ 119,823 $ 24,952 $ 24,995 Common stocks 155,732 172,312 69,503 82,158 64,393 77,031 Mutual funds 2,405 3,633 2,402 3,143 2,384 3,031 Other investments 1,378 1,491 1,275 1,472 696 934 Total trading securities 275,412 293,588 192,935 206,596 92,425 105,991 Available for sale securities: Common stocks 130,869 130,737 150,000 135,701 150,000 125,070 Mutual funds 103 284 206 500 206 481 Total available for sale securities 130,972 131,021 150,206 136,201 150,206 125,551 Total investments in securities $ 406,384 $ 424,609 $ 343,141 $ 342,797 $ 242,631 $ 231,542 Securities sold, not yet purchased at September 30, 2017, December 31, 2016 and September 30, 2016 consisted of the following: September 30, 2017 December 31, 2016 September 30, 2016 Proceeds Fair Value Proceeds Fair Value Proceeds Fair Value Trading securities: (In thousands) Common stocks $ 7,906 $ 8,558 $ 9,583 $ 9,947 $ 3,697 $ 3,948 Other investments 1 501 27 37 245 267 Total securities sold, not yet purchased $ 7,907 $ 9,059 $ 9,610 $ 9,984 $ 3,942 $ 4,215 Investments in affiliated registered investment companies at September 30, 2017, December 31, 2016 and September 30, 2016 consisted of the following: September 30, 2017 December 31, 2016 September 30, 2016 Cost Fair Value Cost Fair Value Cost Fair Value (In thousands) Trading securities: Mutual funds $ 40,095 $ 46,390 $ 40,096 $ 45,351 $ 40,096 $ 44,799 Total trading securities 40,095 46,390 40,096 45,351 40,096 44,799 Available for sale securities: Closed-end funds 65,180 90,516 62,890 80,650 61,375 75,392 Mutual funds 4,384 6,159 4,396 5,644 4,408 6,031 Total available for sale securities 69,564 96,675 67,286 86,294 65,783 81,423 Total investments in affiliated registered investment companies $ 109,659 $ 143,065 $ 107,382 $ 131,645 $ 105,879 $ 126,222 The following table identifies all reclassifications out of accumulated other comprehensive income (“AOCI”) into income for the three and nine months ended September 30, 2017 and 2016 (in thousands): Amount Affected Line Items Reason for Reclassified in the Statements Reclassification from AOCI Of Income from AOCI Three months ended September 30, 2017 2016 $ 125 $ - Net gain/(loss) from investments Realized gain on sale of AFS securities 125 - Income/(loss) before income taxes (45 ) - Income tax provision $ 80 $ - Net income/(loss) Amount Affected Line Items Reason for Reclassified in the Statements Reclassification from AOCI Of Income from AOCI Nine months ended September 30, 2017 2016 $ 167 $ 348 Net gain/(loss) from investments Realized gain on sale of AFS securities (19,131 ) (298 ) Net gain/(loss) from investments OTT impairment of AFS securities (18,964 ) 50 Income/(loss) before income taxes 6,827 (18 ) Income tax provision $ (12,137 ) $ 32 Net income/(loss) The Company recognizes all equity derivatives as either assets or liabilities measured at fair value and includes them in either investments in securities or securities sold, not yet purchased on the condensed consolidated statements of financial condition. From time to time, the Company and/or the partnerships and offshore funds that the Company consolidates will enter into hedging transactions to manage their exposure to foreign currencies and equity prices related to their investments. At September 30, 2017, December 31, 2016 and September 30, 2016, we held derivative contracts on 1.8 million equity shares, 16,000 equity shares and 24,000 equity shares, respectively, that are included in investments in securities or securities sold, not yet purchased on the condensed consolidated statements of financial condition. We had no foreign exchange contracts outstanding at September 30, 2017 and December 31, 2016 and September 30, 2016. Generally, these transactions are not designated as hedges for accounting purposes, and, therefore changes in fair values of these derivatives are included in net gain/(loss) from investments on the condensed consolidated statements of income. The following table identifies the fair values of all derivatives held by the Company (in thousands): Asset Derivatives Liability Derivatives Statement of Fair Value Statement of Fair Value Financial Condition September 30, December 31, September 30, Financial Condition September 30, December 31, September 30, Location 2017 2016 2016 Location 2017 2016 2016 Derivatives designated as hedging instruments under FASB ASC 815-20 Foreign exchange Receivable from contracts brokers $ - $ - $ - Payable to brokers $ - $ - $ - Sub total $ - $ - $ - $ - $ - $ - Derivatives not designated as hedging instruments under FASB ASC 815-20 Equity contracts Investments in Securities sold, securities $ 151 $ 127 $ 178 not yet purchased $ 501 $ 37 $ 33 Foreign exchange Receivable from contracts brokers - - - Payable to brokers - - - Sub total $ 151 $ 127 $ 178 $ 501 $ 37 $ 33 Total derivatives $ 151 $ 127 $ 178 $ 501 $ 37 $ 33 The following table identifies gains and losses of all derivatives held by the Company (in thousands): Type of Derivative Income Statement Location Three Months Ended September 30, Nine Months Ended September 30, 2017 2016 2017 2016 Foreign exchange contracts Net gain/(loss) from investments $ - $ - $ - $ 1,373 Equity contracts Net gain/(loss) from investments (456 ) 159 (490 ) 204 Total $ (456 ) $ 159 $ (490 ) $ 1,577 The Company is a party to enforceable master netting arrangements for swaps entered into with major U.S. financial institutions as part of the investment strategy of the Company’s proprietary portfolio. They are typically not used as hedging instruments. These swaps, while settled on a net basis with the counterparties are shown gross in assets and liabilities on the condensed consolidated statements of financial condition. The swaps have a firm contract end date and are closed out and settled when each contract expires. Gross Amounts Not Offset in the Statements of Financial Condition Gross Gross Amounts Net Amounts of Amounts of Offset in the Assets Presented Recognized Statements of in the Statements of Financial Cash Collateral Assets Financial Condition Financial Condition Instruments Received Net Amount Swaps: (In thousands) September 30, 2017 $ 151 $ - $ 151 $ (151 ) $ - $ - December 31, 2016 96 - 96 (9 ) - 87 September 30, 2016 $ 178 $ - $ 178 $ (14 ) $ - $ 164 Gross Amounts Not Offset in the Statements of Financial Condition Gross Gross Amounts Net Amounts of Amounts of Offset in the Liabilities Presented Recognized Statements of in the Statements of Financial Cash Collateral Liabilities Financial Condition Financial Condition Instruments Pledged Net Amount Swaps: (In thousands) September 30, 2017 $ 500 $ - $ 500 $ (151 ) $ - $ 349 December 31, 2016 9 - 9 (9 ) - - September 30, 2016 $ 14 $ - $ 14 $ (14 ) $ - $ - The following is a summary of the cost, gross unrealized gains, gross unrealized losses and fair value of available for sale investments as of September 30, 2017, December 31, 2016 and September 30, 2016: September 30, 2017 Gross Gross Unrealized Unrealized Cost Gains Losses Fair Value (In thousands) Common stocks $ 130,869 $ - $ (132 ) $ 130,737 Closed-end funds 65,180 25,535 (199 ) 90,516 Mutual funds 4,487 1,956 - 6,443 Total available for sale securities $ 200,536 $ 27,491 $ (331 ) $ 227,696 December 31, 2016 Gross Gross Unrealized Unrealized Cost Gains Losses Fair Value (In thousands) Common stocks $ 150,000 $ - $ (14,299 ) $ 135,701 Closed-end funds 62,890 17,760 - 80,650 Mutual funds 4,602 1,542 - 6,144 Total available for sale securities $ 217,492 $ 19,302 $ (14,299 ) $ 222,495 September 30, 2016 Gross Gross Unrealized Unrealized Cost Gains Losses Fair Value (In thousands) Common stocks $ 150,000 $ - $ (24,930 ) $ 125,070 Closed-end funds 61,375 14,027 (10 ) 75,392 Mutual funds 4,614 1,898 - 6,512 Total available for sale securities $ 215,989 $ 15,925 $ (24,940 ) $ 206,974 Changes in net unrealized gains, net of taxes, for the three months ended September 30, 2017 and September 30, 2016 of $1.7 million in gains and $9.3 million in losses, respectively, have been included in other comprehensive income, a component of equity, at September 30, 2017 and September 30, 2016. Return of capital on available for sale securities was $0.5 million and $0.2 million for the three months ended September 30, 2017 and 2016, respectively. Proceeds from sales of investments available for sale were approximately $0.2 million for the three months ended September 30, 2017. For the three months ended September 30, 2017, gross gains on the sale of investments available for sale amounted to $0.1 million and were reclassified from other comprehensive income into net gain/(loss) from investments in the condensed consolidated statements of income. There were no proceeds from the sales of investments available for sale and no gross gains on the sale of investments available for sale for the three months ended September 30, 2016. There were no losses on the sale of investments available for sale for the three months ended September 30, 2017 or September 30, 2016. Changes in net unrealized gains/(losses), net of taxes, for the nine months ended September 30, 2017 and September 30, 2016 of $14.2 million in gains and $4.8 million in losses, respectively, have been included in other comprehensive income, a component of equity, at September 30, 2017 and September 30, 2016. Return of capital on available for sale securities was $1.3 million and $0.8 million for the nine months ended September 30, 2017 and September 30, 2016, respectively. Proceeds from sales of investments available for sale were approximately $0.3 million and $0.8 million for the nine months ended September 30, 2017 and 2016, respectively. For the nine months ended September 30, 2017 and 2016, gross gains on the sale of investments available for sale amounted to $0.2 million and $0.3 million and were reclassified from other comprehensive income into net gain/(loss) from investments in the condensed consolidated statements of income. There were no losses on the sale of investments available for sale for the nine months ended September 30, 2017 or September 30, 2016. The Company determines the cost of a security sold by using specific identification. Investments classified as available for sale that are in an unrealized loss position for which other-than-temporary impairment has not been recognized consisted of the following (in thousands): September 30, 2017 December 31, 2016 September 30, 2016 Unrealized Unrealized Unrealized Cost Losses Fair Value Cost Losses Fair Value Cost Losses Fair Value Common stocks $ 130,869 $ (132 ) $ 130,737 $ 150,000 $ (14,299 ) $ 135,701 $ 150,000 $ (24,930 ) $ 125,070 Closed-end funds 1,864 (199 ) 1,665 - - - 3,162 (10 ) 3,152 Total available for sale securities in unrealized loss position $ 132,733 $ (331 ) $ 132,402 $ 150,000 $ (14,299 ) $ 135,701 $ 153,162 $ (24,940 ) $ 128,222 There were no losses on AFS securities deemed to be OTT for the three months ended September 30, 2017 and 2016. For the nine months ended September 30, 2017, AC recognized a $19.1 million OTT on the GBL shares due to the magnitude and persistence of the unrealized loss. For the nine months ended September 30, 2016, the Company reflected $0.3 million of losses on AFS securities deemed to be OTT. At September 30, 2017, two holdings with unrealized losses were not deemed to be other-than-temporarily impaired due to the length of time that they had been in a loss position and our evaluation of issuer-specific and industry-specific considerations. One of these investments was a closed-end fund with diversified holdings across multiple companies and industries. This holding was impaired for nine months at September 30, 2017. The second holding was the GBL stock that was, as noted above, deemed to have an “other than temporary impairment” during the nine months ended September 30, 2017, but which has subsequently had further unrealized losses. These further losses were not deemed to be other-than-temporarily impaired. The value of the two holdings at September 30, 2017 was $132.4 million. If these holdings continue to be impaired, we may need to record this impairment in a future period on the condensed consolidated statements of income for the amount of the unrealized losses which was $0.3 million at September 30, 2017. At December 31, 2016, there was one holding in an unrealized loss position which was not deemed to be other-than-temporarily impaired due to the length of time that it had been consecutively in a loss position and our evaluation of issuer-specific and industry-specific considerations. This holding was a common stock and was impaired for seven consecutive months. The fair value of this holding exceeded its cost during the year ended December 31, 2016. At September 30, 2016, there were two holdings in unrealized loss positions that were not deemed to be other-than-temporarily impaired due to the length of time that they had been in a loss position and our evaluation of issuer-specific and industry-specific considerations. One of these investments was a closed-end fund with diversified holdings across multiple companies and industries that had been impaired for one month. The second holding was a common stock that had been impaired for four months.

Fair Value

Fair Value	9 Months Ended
	Sep. 30, 2017
Fair Value [Abstract]
Fair Value	C. Fair Value The following tables present information about the Company’s assets and liabilities by major category measured at fair value on a recurring basis as of September 30, 2017, December 31, 2016 and September 30, 2016 and indicates the fair value hierarchy of the valuation techniques utilized by the Company to determine such fair value. Investments in certain entities that calculate net asset value per share and other investments that are not held at fair value are provided as separate items to permit reconciliation of the fair value of investments included in the fair value hierarchy to the total amounts presented in the condensed consolidated statements of financial condition. Assets and Liabilities Measured at Fair Value on a Recurring Basis as of September 30, 2017 (in thousands) Quoted Prices in Active Significant Other Significant Investments Other Assets Balance as of Markets for Identical Observable Unobservable Measured at Not Held at September 30, Assets Assets (Level 1) Inputs (Level 2) Inputs (Level 3) NAV (a) Fair Value (b) 2017 Cash equivalents $ 240,727 $ - $ - $ - $ - $ 240,727 Investments in partnerships - - - 138,035 3,059 141,094 Investments in securities (including GBL stock): AFS - Common stocks 130,737 - - - - 130,737 AFS - Mutual funds 284 - - - - 284 Trading - Gov't obligations 116,152 - - - - 116,152 Trading - Common stocks 171,835 1 476 - - 172,312 Trading - Mutual funds 3,633 - - - - 3,633 Trading - Other 994 151 346 - - 1,491 Total investments in securities 423,635 152 822 - - 424,609 Investments in affiliated registered investment companies: AFS - Closed-end funds 90,516 - - - - 90,516 AFS - Mutual funds 6,159 - - - - 6,159 Trading - Mutual funds 46,390 - - - - 46,390 Total investments in affiliated registered investment companies 143,065 - - - - 143,065 Total investments 566,700 152 822 138,035 3,059 708,768 Total assets at fair value $ 807,427 $ 152 $ 822 $ 138,035 $ 3,059 $ 949,495 Liabilities Trading - Common stocks $ 8,558 $ - $ - $ - $ - $ 8,558 Trading - Other - 501 - - - 501 Securities sold, not yet purchased $ 8,558 $ 501 $ - $ - $ - $ 9,059 Assets and Liabilities Measured at Fair Value on a Recurring Basis as of December 31, 2016 (in thousands) Quoted Prices in Active Significant Other Significant Investments Other Assets Balance as of Markets for Identical Observable Unobservable Measured at Not Held at December 31, Assets Assets (Level 1) Inputs (Level 2) Inputs (Level 3) NAV (a) Fair Value (b) 2016 Cash equivalents $ 314,082 $ - $ - $ - $ - $ 314,082 Investments in partnerships - - - 125,527 3,871 129,398 Investments in securities (including GBL stock): AFS - Common stocks 135,701 - - - - 135,701 AFS - Mutual funds 500 - - - - 500 Trading - Gov't obligations 119,823 - - - - 119,823 Trading - Common stocks 81,696 1 461 - - 82,158 Trading - Mutual funds 3,143 - - - - 3,143 Trading - Other 1,062 127 283 - - 1,472 Total investments in securities 341,925 128 744 - - 342,797 Investments in affiliated registered investment companies: AFS - Closed-end funds 80,650 - - - - 80,650 AFS - Mutual funds 5,644 - - - - 5,644 Trading - Mutual funds 45,351 - - - - 45,351 Total investments in affiliated registered investment companies 131,645 - - - - 131,645 Total investments 473,570 128 744 125,527 3,871 603,840 Total assets at fair value $ 787,652 $ 128 $ 744 $ 125,527 $ 3,871 $ 917,922 Liabilities Trading - Common stocks $ 9,947 $ - $ - $ - $ - $ 9,947 Trading - Other - 37 - - - 37 Securities sold, not yet purchased $ 9,947 $ 37 $ - $ - $ - $ 9,984 Assets and Liabilities Measured at Fair Value on a Recurring Basis as of September 30, 2016 (in thousands) Quoted Prices in Active Significant Other Significant Investments Other Assets Balance as of Markets for Identical Observable Unobservable Measured at Not Held at September 30, Assets Assets (Level 1) Inputs (Level 2) Inputs (Level 3) NAV (a) Fair Value (b) 2016 Cash equivalents $ 402,391 $ - $ - $ - $ - $ 402,391 Investments in partnerships - - - 125,977 2,221 128,198 Investments in securities (including GBL stock): AFS - Common stocks 125,070 - - - - 125,070 AFS - Mutual funds 481 - - - - 481 Trading - Gov't obligations 24,995 - - - - 24,995 Trading - Common stocks 76,570 - 461 - - 77,031 Trading - Mutual funds 3,031 - - - - 3,031 Trading - Other 476 178 280 - - 934 Total investments in securities 230,623 178 741 - - 231,542 Investments in affiliated registered investment companies: AFS - Closed-end funds 72,240 3,152 - - - 75,392 AFS - Mutual funds 6,031 - - - - 6,031 Trading - Mutual funds 44,799 - - - - 44,799 Total investments in affiliated registered investment companies 123,070 3,152 - - - 126,222 Total investments 353,693 3,330 741 125,977 2,221 485,962 Total assets at fair value $ 756,084 $ 3,330 $ 741 $ 125,977 $ 2,221 $ 888,353 Liabilities Trading - Common stocks $ 3,948 $ - $ - $ - $ - $ 3,948 Trading - Other - 267 - - - 267 Securities sold, not yet purchased $ 3,948 $ 267 $ - $ - $ - $ 4,215 (a) Includes certain investments measured at fair value using NAV (or its equivalent) as a practical expedient. These investments have not been classified in the fair value hierarchy. (b) Includes certain equity method investments which are not accounted for under a fair value measure. In accordance with GAAP, certain equity method investees do not account for their financial assets and liabilities under fair value measures; therefore, the Company’s investment in such equity method investees may not represent fair value. The following tables present additional information about assets by major category measured at fair value on a recurring basis and for which the Company has utilized Level 3 inputs to determine fair value: Changes in Level 3 Assets and Liabilities Measured at Fair Value on a Recurring Basis for the Three Months Ended September 30, 2017 (in thousands) Total Unrealized Gains or Total Total Realized and (Losses) Realized June 30, Unrealized Gains or Included in and Transfers September 30, 2017 (Losses) in Income Other Unrealized In and/or 2017 Beginning AFS Comprehensive Gains or (Out) of Ending Asset Balance Trading Investments Income (Losses) Purchases Sales Level 3 Balance Financial instruments owned: Trading - Common stocks $ 510 $ 2 $ - $ - $ 2 $ - $ - $ (36 ) $ 476 Trading - Other 449 39 - - 39 - (142 ) - 346 Total $ 959 $ 41 $ - $ - $ 41 - $ (142 ) $ (36 ) $ 822 There were no transfers between Level 1 and Level 2 during the three months ended September 30, 2017. During the three months ended September 30, 2017, the Company transferred an investment with a value of approximately $36,000 from Level 3 to Level 1. The reclassification was due to increased availability of market price quotations and was based on the value at the beginning of the period in which the transfer occurred. Changes in Level 3 Assets and Liabilities Measured at Fair Value on a Recurring Basis for the Three Months Ended September 30, 2016 (in thousands) Total Unrealized Gains or Total Total Realized and (Losses) Realized June 30, Unrealized Gains or Included in and Transfers September 30, 2016 (Losses) in Income Other Unrealized In and/or 2016 Beginning AFS Comprehensive Gains or (Out) of Ending Asset Balance Trading Investments Income (Losses) Purchases Sales Level 3 Balance Financial instruments owned: Trading - Common stocks $ 502 $ (41 ) $ - $ - $ (41 ) $ - $ - $ - $ 461 Trading - Other 296 4 - - 4 - (20 ) - 280 Total $ 798 $ (37 ) $ - $ - $ (37 ) $ - $ (20 ) $ - $ 741 There were no transfers between any Levels during the three months ended September 30, 2016. Changes in Level 3 Assets and Liabilities Measured at Fair Value on a Recurring Basis for the Nine Months Ended September 30, 2017 (in thousands) Total Unrealized Gains or Total Total Realized and (Losses) Realized December 31, Unrealized Gains or Included in and Transfers September 30, 2016 (Losses) in Income Other Unrealized In and/or 2017 Beginning AFS Comprehensive Gains or (Out) of Ending Asset Balance Trading Investments Income (Losses) Purchases Sales Level 3 Balance Financial instruments owned: Trading - Common stocks $ 461 $ 51 $ - $ - $ 51 $ - $ - $ (36 ) $ 476 Trading - Other 283 46 - - 46 167 (150 ) - 346 Total $ 744 $ 97 $ - $ - $ 97 $ 167 $ (150 ) $ (36 ) $ 822 There were no transfers between Level 1 and Level 2 during the nine months ended September 30, 2017. During the nine months ended September 30, 2017, the Company transferred an investment with a value of approximately $36,000 from Level 3 to Level 1. The reclassification was due to increased availability of market price quotations and was based on the value at the beginning of the period in which the transfer occurred. Changes in Level 3 Assets and Liabilities Measured at Fair Value on a Recurring Basis for the Nine Months Ended September 30, 2016 (in thousands) Total Unrealized Gains or Total Total Realized and (Losses) Realized December 31, Unrealized Gains or Included in and Transfers September 30, 2015 (Losses) in Income Other Unrealized In and/or 2016 Beginning AFS Comprehensive Gains or (Out) of Ending Asset Balance Trading Investments Income (Losses) Purchases Sales Level 3 Balance Financial instruments owned: Trading - Common stocks $ 508 $ (47 ) $ - $ - $ (47 ) $ - $ - $ - $ 461 Trading - Other 305 (5 ) - - (5 ) - (20 ) - 280 Total $ 813 $ (52 ) $ - $ - $ (52 ) $ - $ (20 ) $ - $ 741 There were no transfers between any Levels during the nine months ended September 30, 2016.

Investments in Partnerships, Of

Investments in Partnerships, Offshore Funds and Variable Interest Entities ("VIEs")	9 Months Ended
	Sep. 30, 2017
Investments in Partnerships, Offshore Funds and Variable Interest Entities ("VIEs") [Abstract]
Investments in Partnerships, Offshore Funds and Variable Interest Entities ("VIEs")	D. Investments in Partnerships, Offshore Funds and Variable Interest Entities (“VIEs”) The Company is general partner or co-general partner of various affiliated entities in which the Company has investments totaling $122.6 million, $112.3 million and $113.4 million at September 30, 2017, December 31, 2016 and September 30, 2016, respectively, and whose underlying assets consist primarily of marketable securities (“Affiliated Entities”). We also have investments in unaffiliated entities of $18.5 million, $17.1 million and $14.8 million at September 30, 2017, December 31, 2016 and September 30, 2016, respectively (“Unaffiliated Entities”). On a quarterly basis, we evaluate each entity to determine the appropriate accounting treatment and related disclosures. If an entity qualifies as a variable interest entity (a “VIE”), we consolidate it if: (a) we are its primary beneficiary and absorb the majority of expected losses and receive the majority of expected gains; and (b) the unaffiliated investors lack substantive rights to either dissolve the entity or remove the general partner. If an entity qualifies as a voting interest entity (a “VOE”), we consolidate it if we control the entity through a majority voting interest or other means. Based on the consolidation guidance, we have determined that three and two entities are required to be consolidated in our condensed consolidated financial statements for the periods ended September 30, 2017 and September 30, 2016, respectively. Certain of the consolidated entities invest their assets in other investment funds (a “Consolidated Feeder Fund” or “CFF”). Because the CFFs are investment companies under GAAP, they retain their specialized accounting and reflect their investments at fair value as described in Note C. The following table highlights the number of entities that we consolidate as well as the basis under which they are consolidated: Entities consolidated CFFs Partnerships Offshore Funds Total VIEs VOEs VIEs VOEs VIEs VOEs VIEs VOEs Entities consolidated at December 31, 2015 1 2 - 2 1 - 2 4 Additional consolidated entities - - 1 - - - 1 - Deconsolidated entities (1) (1) - (2) (1) - (2) (3) Entities consolidated at September 30, 2016 - 1 1 - - - 1 1 Additional consolidated entities - - - - - - - - Deconsolidated entities - - - - - - - - Entities consolidated at December 31, 2016 - 1 1 - - - 1 1 Additional consolidated entities - - - - - 1 - 1 Deconsolidated entities - - - - - - - - Entities consolidated at September 30, 2017 - 1 1 - - 1 1 2 The following table provides details of our investments in partnerships by the accounting method used and investment type (in thousands): September 30, 2017 Investment Type Affiliated Unaffiliated Consolidated Accounting method Feeder Funds Partnerships Offshore Funds Partnerships Offshore Funds Total Fair Value $ 8,297 $ - $ - $ - $ - $ 8,297 Equity Method - 41,169 73,146 6,104 12,378 132,797 Total $ 8,297 $ 41,169 $ 73,146 $ 6,104 $ 12,378 $ 141,094 December 31, 2016 Investment Type Affiliated Unaffiliated Consolidated Accounting method Feeder Funds Partnerships Offshore Funds Partnerships Offshore Funds Total Fair Value $ 8,343 $ - $ - $ - $ - $ 8,343 Equity Method - 33,202 70,745 6,761 10,347 121,055 Total $ 8,343 $ 33,202 $ 70,745 $ 6,761 $ 10,347 $ 129,398 September 30, 2016 Investment Type Affiliated Unaffiliated Consolidated Accounting method Feeder Funds Partnerships Offshore Funds Partnerships Offshore Funds Total Fair Value $ 8,123 $ - $ - $ - $ - $ 8,123 Equity Method - 40,516 64,810 5,438 9,311 120,075 Total $ 8,123 $ 40,516 $ 64,810 $ 5,438 $ 9,311 $ 128,198 The following table includes the net impact by line item on the condensed consolidated statements of financial condition for each category of consolidated entity (in thousands): September 30, 2017 Prior to Offshore Consolidation CFFs Partnerships Funds As Reported Assets Cash and cash equivalents $ 234,124 $ - $ 119 $ 8,059 $ 242,302 Investments in securities (including GBL stock) 320,021 - 6,948 97,640 424,609 Investments in affiliated investment companies 195,401 - - (52,336 ) 143,065 Investments in partnerships 155,462 3,803 (8,936 ) (9,235 ) 141,094 Receivable from brokers 8,208 - 2,217 5,328 15,753 Investment advisory fees receivable 1,445 (4 ) (8 ) - 1,433 Other assets 11,163 - - 100 11,263 Total assets $ 925,824 $ 3,799 $ 340 $ 49,556 $ 979,519 Liabilities and equity Securities sold, not yet purchased $ 8,585 $ - $ - $ 474 $ 9,059 Accrued expenses and other liabilities 19,031 15 28 11,059 30,133 Redeemable noncontrolling interests - 3,784 312 38,023 42,119 Total equity 898,208 - - - 898,208 Total liabilities and equity $ 925,824 $ 3,799 $ 340 $ 49,556 $ 979,519 December 31, 2016 Prior to Offshore Consolidation CFFs Partnerships Funds As Reported Assets Cash and cash equivalents $ 313,785 $ - $ 308 $ - $ 314,093 Investments in securities (including GBL stock) 336,459 - 6,338 - 342,797 Investments in affiliated investment companies 131,645 - - - 131,645 Investments in partnerships 133,794 3,964 (8,360 ) - 129,398 Receivable from brokers 10,542 - 2,046 - 12,588 Investment advisory fees receivable 9,800 (8 ) (8 ) - 9,784 Other assets 12,298 - - - 12,298 Total assets $ 948,323 $ 3,956 $ 324 $ - $ 952,603 Liabilities and equity Securities sold, not yet purchased $ 9,984 $ - $ - $ - $ 9,984 Accrued expenses and other liabilities 64,317 13 37 - 64,367 Redeemable noncontrolling interests - 3,943 287 - 4,230 Total equity 874,022 - - - 874,022 Total liabilities and equity $ 948,323 $ 3,956 $ 324 $ - $ 952,603 September 30, 2016 Prior to Offshore Consolidation CFFs Partnerships Funds As Reported Assets Cash and cash equivalents $ 402,395 $ - $ 8 $ - $ 402,403 Investments in securities (including GBL stock) 224,996 - 6,546 - 231,542 Investments in affiliated investment companies 126,222 - - - 126,222 Investments in partnerships 132,564 3,730 (8,096 ) - 128,198 Receivable from brokers 17,943 - 1,864 - 19,807 Investment advisory fees receivable 1,944 (7 ) (5 ) - 1,932 Other assets 14,707 - - - 14,707 Total assets $ 920,771 $ 3,723 $ 317 $ - $ 924,811 Liabilities and equity Securities sold, not yet purchased $ 4,215 $ - $ - $ - $ 4,215 Accrued expenses and other liabilities 18,487 11 30 - 18,528 Redeemable noncontrolling interests - 3,712 287 - 3,999 Total equity 898,069 - - - 898,069 Total liabilities and equity $ 920,771 $ 3,723 $ 317 $ - $ 924,811 The following table includes the net impact by line item on the condensed consolidated statements of income for each category of consolidated entity (in thousands): Three Months Ended September 30, 2017 Prior to Offshore Consolidation CFFs Partnerships Funds As Reported Total revenues $ 5,252 $ (4 ) $ - $ - $ 5,248 Total expenses 10,188 28 11 1,133 11,360 Operating loss (4,936 ) (32 ) (11 ) (1,133 ) (6,112 ) Total other income, net 6,522 32 22 936 7,512 Income (loss) before income taxes 1,586 - 11 (197 ) 1,400 Income tax provision 67 - - - 67 Net income (loss) 1,519 - 11 (197 ) 1,333 Net income (loss) attributable to noncontrolling interests - - 11 (197 ) (186 ) Net income attributable to AC Group $ 1,519 $ - $ - $ - $ 1,519 Three Months Ended September 30, 2016 Prior to Offshore Consolidation CFFs Partnerships Funds As Reported Total revenues $ 5,456 $ (4 ) $ (1 ) $ - $ 5,451 Total expenses 9,910 29 9 - 9,948 Operating loss (4,454 ) (33 ) (10 ) - (4,497 ) Total other income, net 10,220 110 3 - 10,333 Income (loss) before income taxes 5,766 77 (7 ) - 5,836 Income tax provision 1,807 - - - 1,807 Net income (loss) 3,959 77 (7 ) - 4,029 Net income (loss) attributable to noncontrolling interests - 77 (7 ) - 70 Net income attributable to AC Group $ 3,959 $ - $ - $ - $ 3,959 Nine Months Ended September 30, 2017 Prior to Offshore Consolidation CFFs Partnerships Funds As Reported Total revenues $ 15,345 $ (13 ) $ (2 ) $ - $ 15,330 Total expenses 30,959 103 32 1,133 32,227 Operating loss (15,614 ) (116 ) (34 ) (1,133 ) (16,897 ) Total other income (expense), net (16 ) 191 61 936 1,172 Income (loss) before income taxes (15,630 ) 75 27 (197 ) (15,725 ) Income tax provision (8,667 ) - - - (8,667 ) Net income (loss) (6,963 ) 75 27 (197 ) (7,058 ) Net income (loss) attributable to noncontrolling interests - 75 27 (197 ) (95 ) Net loss attributable to AC Group $ (6,963 ) $ - $ - $ - $ (6,963 ) Nine Months Ended September 30, 2016 Prior to Offshore Consolidation CFFs Partnerships Funds As Reported Total revenues $ 14,946 $ (12 ) $ (2 ) $ - $ 14,932 Total expenses 27,170 91 35 - 27,296 Operating loss (12,224 ) (103 ) (37 ) - (12,364 ) Total other income, net 21,522 414 42 - 21,978 Income before income taxes 9,298 311 5 - 9,614 Income tax provision 2,773 - - - 2,773 Net income 6,525 311 5 - 6,841 Net income (loss) attributable to noncontrolling interests (46 ) 311 5 - 270 Net income attributable to AC Group $ 6,571 $ - $ - $ - $ 6,571 Variable Interest Entities With respect to each consolidated VIE, its assets may only be used to satisfy its obligations. The investors and creditors of these VIEs have no recourse to the Company’s general assets. In addition, the Company neither benefits from the VIE’s assets nor bears the related risks beyond its beneficial interest in the VIE. The following table presents the balances of the VIE that is consolidated at September 30, 2017, December 31, 2016 and September 30, 2016 and included on the condensed consolidated statements of financial condition as well as AC Group’s net interest in the VIE: September 30, December 31, September 30, 2017 2016 2016 (In thousands) Cash and cash equivalents $ 119 $ 308 $ 8 Investments in securities 6,948 6,338 6,546 Receivable from brokers 2,217 2,046 1,864 Other assets (8 ) (8 ) (5 ) Accrued expenses and other liabilities (28 ) (37 ) (29 ) Redeemable noncontrolling interests (312 ) (287 ) (288 ) AC Group's net interests in consolidated VIE $ 8,936 $ 8,360 $ 8,096

Income Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2017
Income Taxes [Abstract]
Income Taxes	E. Income Taxes The effective tax rate (“ETR”) for the three months ended September 30, 2017 and September 30, 2016 was 4.8% and 31.0%, respectively. The ETR in the third quarter of 2017 differs from the standard corporate tax rate of 34% primarily due to the benefit of (a) the adoption of ASU 2016-09 (as discussed below) and (b) the dividends received deduction. The ETR in the third quarter of 2016 differs from the standard corporate tax rate of 34% primarily due to the benefit of the dividends received deduction. The ETR for the nine months ended September 30, 2017 and September 30, 2016 was 55.1% and 28.8%, respectively. The ETR for the nine months ended September 30, 2017 primarily differs from the standard corporate tax rate as a result of the benefit of (a) the adoption of ASU 2016-09, (b) the contribution of appreciated securities, and (c) the dividends received deduction. Due to the loss for the nine months ended September 30, 2017, the tax benefits noted above increase the ETR to 55.1%. The ETR for the nine months ended September 30, 2016 differs from the standard corporate tax rate of 34% primarily due to the benefit of the dividends received deduction. Since the nine months ended September 30, 2016 was a profit, the tax benefit reduced the ETR to 28.8%. ASU 2016-09, which we adopted on January 1, 2017, simplifies several aspects of accounting for employee share-based payment transactions. Under ASU 2016-09, we recognize the tax benefit of the difference between the deduction for tax purposes and the compensation cost recognized for financial reporting purposes as part of income tax expense rather than additional paid-in capital.

Earnings Per Share

Earnings Per Share	9 Months Ended
	Sep. 30, 2017
Earnings Per Share [Abstract]
Earnings Per Share	F. Basic earnings per share is computed by dividing net income/(loss) per share attributable to our shareholders by the weighted average number of shares outstanding during the period. Diluted earnings per share is computed by dividing net income/(loss) per share attributable to our shareholders by the weighted average number of shares outstanding during the period, adjusted for the dilutive effect of restricted stock awards. The computations of basic and diluted net income/(loss) per share are as follows: Three Months Ended September 30, (in thousands, except per share amounts) 2017 2016 Basic: Net income attributable to Associated Capital Group, Inc.'s shareholders $ 1,519 $ 3,959 Weighted average shares outstanding 23,841 24,918 Basic net income attributable to Associated Capital Group, Inc.'s shareholders per share $ 0.06 $ 0.16 Diluted: Net income attributable to Associated Capital Group, Inc.'s shareholders $ 1,519 $ 3,959 Weighted average share outstanding 23,841 24,918 Dilutive restricted stock awards - 301 Total 23,841 25,219 Diluted net income attributable to Associated Capital Group, Inc.'s shareholders per share $ 0.06 $ 0.16 Nine Months Ended September 30, 2017 2016 Basic: Net income/(loss) attributable to Associated Capital Group, Inc.'s shareholders $ (6,963 ) $ 6,571 Weighted average shares outstanding 23,826 24,879 Basic net income/(loss) atttributable to Associated Capital Group, Inc.'s shareholders per share $ (0.29 ) $ 0.26 Diluted: Net income/(loss) attributable to Associated Capital Group, Inc.'s shareholders $ (6,963 ) $ 6,571 Weighted average shares outstanding 23,826 24,879 Dilutive restricted stock awards - 315 Total 23,826 25,194 Diluted net income/(loss) attributable to Associated Capital Group, Inc.'s shareholders per share $ (0.29 ) $ 0.26 Diluted weighted average shares outstanding for the nine months ended September 30, 2017 exclude restricted stock awards as we have a net loss for that period and their inclusion would be anti-dilutive.

Stockholders' Equity

Stockholders' Equity	9 Months Ended
	Sep. 30, 2017
Stockholders' Equity [Abstract]
Stockholders' Equity	G. Stockholders’ Equity Shares outstanding were 23.8 million, 24.3 million and 25.4 million on September 30, 2017, December 31, 2016, and September 30, 2016, respectively. Dividends During each of the nine months ended September 30, 2017 and 2016, the Company declared dividends of $0.10 per share to class A and class B shareholders. Voting Rights The holders of Class A Common stock (“Class A Stock”) and Class B Common stock (“Class B Stock”) have identical rights except that (a) holders of Class A Stock are entitled to one vote per share, while holders of Class B Stock are entitled to ten votes per share on all matters to be voted on by shareholders in general, and (b) holders of each share class are not eligible to vote on matters relating exclusively to the other share class. Stock Award and Incentive Plan The Company maintains one stock award and incentive plan (the “Plan”) approved by the shareholders at the Company’s annual meeting held on May 3, 2016. The Plan seeks to provide incentives which will attract and retain individuals key to the success of AC through direct or indirect ownership of our common stock. Benefits under the Plan may be granted in any one or a combination of stock options, stock appreciation rights, restricted stock, restricted stock units, stock awards, dividend equivalents and other stock or cash based awards. A maximum of 2.0 million shares of Class A Stock have been reserved for issuance under the Plan. On November 30, 2015, in connection with the Spin-off, the Company issued RSAs for 554,100 shares (“AC RSAs”) to employees who held RSAs for 554,100 GAMCO shares (“GAMCO RSAs”). All grants of the AC RSAs were recommended by the Company's Executive Chairman, who did not receive any RSAs, and approved by the Compensation Committee of the Board of Directors. The value of the AC RSAs, net of estimated forfeitures, is recognized as expense over the respective vesting period which is either (1) five years (30% three years and 70% five years from the date of grant, respectively), or (2) ten years (30% three years and 10% each year thereafter from the date of grant, respectively). 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 AC RSAs are in addition to any GAMCO RSAs which an employee held on the date of the Spin-off. The value of the GAMCO RSAs held by AC employees is recognized as expense by the Company over the remaining vesting period because the employees’ services are for the benefit of the Company. Terms of the GAMCO RSAs are the same as those of the AC RSAs above. As of December 31, 2016 and September 30, 2016, there were 424,340 AC RSA shares and 427,290 AC RSA shares outstanding, respectively. On June 1, 2017, the Compensation Committee of AC accelerated the vesting of all 420,240 outstanding AC RSAs effective June 15, 2017. As a result, the Company incurred incremental stock-based compensation of $2.5 million for the nine months ended September 30, 2017. On August 7, 2017, the compensation committee of GAMCO’s Board of Directors accelerated the vesting of 201,120 GAMCO RSAs outstanding effective August 31, 2017. As a result, AC recorded an incremental $1.6 million of stock-based compensation for the three and nine months ended September 30, 2017 attributable to the GAMCO RSAs held by AC employees. There continue to be 164,050 GAMCO RSAs outstanding that were not vested as part of this acceleration, and the Company will recognize expense as these RSAs continue to vest. For the three months ended September 30, 2017 and September 30, 2016, we recognized stock-based compensation expense of $1.9 million and $0.7 million, respectively. For the nine months ended September 30, 2017 and September 30, 2016, we recognized stock-based compensation expense of $5.2 million and $2.0 million, respectively. Please note that the Company’s stock-based compensation expense also includes an allocation of GAMCO related stock-based compensation expense with respect to GAMCO teammates who provide services to the Company under our services agreements with GAMCO. Actual and projected stock-based compensation expense for RSA shares for the years ended December 31, 2016 through December 31, 2024 (based on AC and GAMCO awards currently issued or granted) is as follows (in thousands): 2016 2017 2018 2019 2020 2021 2022 2023 2024 Q1 $ 644 $ 444 $ 67 $ 56 $ 26 $ 15 $ 10 $ 5 $ 1 Q2 644 2,920 64 56 22 15 10 5 1 Q3 727 1,862 59 51 18 12 7 3 1 Q4 449 83 56 48 15 10 5 1 - Full Year $ 2,464 $ 5,309 $ 246 $ 211 $ 81 $ 52 $ 32 $ 14 $ 3 The total projected compensation cost allocated to the Company related to non-vested GAMCO RSAs not yet recognized is approximately $0.7 million as of September 30, 2017.

Goodwill and Identifiable Intan

Goodwill and Identifiable Intangible Assets	9 Months Ended
	Sep. 30, 2017
Goodwill and Identifiable Intangible Assets [Abstract]
Goodwill and Identifiable Intangible Assets	H. Goodwill and Identifiable Intangible Assets At September 30, 2017, $3.4 million of goodwill related to GCIA is separately disclosed on the condensed consolidated statements of financial condition. The Company assesses the recoverability of goodwill at least annually, or more often should events warrant, using a qualitative assessment of whether it is more likely than not that an impairment has occurred to determine if a quantitative analysis is required. There were no indicators of impairment for the three months ended September 30, 2017 or September 30, 2016, and as such there was no impairment analysis performed or charge recorded.

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2017
Commitments and Contingencies [Abstract]
Commitments and Contingencies	I. Commitments and Contingencies From time to time, the Company may be named in legal actions and proceedings. These actions may seek substantial or indeterminate compensatory as well as punitive damages or injunctive relief. The Company is also subject to governmental or regulatory examinations or investigations. The examinations or investigations could result in adverse judgments, settlements, fines, injunctions, restitutions or other relief. For any such matters, the condensed consolidated financial statements include the necessary provisions for losses that the Company believes are probable and estimable. Furthermore, the Company evaluates whether there exist losses which may be reasonably possible and will, if material, make the necessary disclosures. However, management believes such amounts, both those that are probable and those that are reasonably possible, are not material to the Company’s financial condition, operations or cash flows at September 30, 2017. The Company indemnifies the clearing brokers of G.research for losses they may sustain from the customer accounts that trade on margin introduced by it. At September 30, 2017, the total amount of customer balances subject to indemnification (i.e. unsecured margin debits) was immaterial. The Company has also entered into arrangements with various other third parties many of which provide for indemnification of the third parties against losses, costs, claims and liabilities arising from the performance of obligations under the agreements. The Company has had no claims or payments pursuant to these or prior agreements and believes the likelihood of a claim being made is remote. The Company’s estimate of the value of such obligations is de minimis, and therefore no accrual has been made on the condensed consolidated financial statements.

Shareholder-Designated Contribu

Shareholder-Designated Contribution Plan	9 Months Ended
	Sep. 30, 2017
Shareholder-Designated Contribution Plan [Abstract]
Shareholder-Designated Contribution Plan	J. During the fourth quarter of 2016, the Company established a Shareholder Designated Charitable Contribution program. Under the program, each shareholder is eligible to designate a charity to which the Company would make a donation at a rate of twenty-five cents per share based upon the actual number of shares registered in the shareholder’s name. Shares held in nominee or street name were not eligible to participate. On February 8, 2017, the Company announced it had again adopted a Shareholder Designated Charitable Contribution program for all registered Class A and Class B shareholders. The Company recorded a cost of $4.9 million related to this contribution which was included in shareholder-designated contribution in the condensed consolidated statements of income.

Contractual Obligations

Contractual Obligations	9 Months Ended
	Sep. 30, 2017
Contractual Obligations [Abstract]
Contractual Obligations	K. In June 2016, AC entered into a sublease agreement with GAMCO effective from April 1, 2016 through March 31, 2017. The Company renewed the sublease agreement with GAMCO in March 2017 for an additional year. Future minimum lease commitments under this operating lease as of September 30, 2017 are as follows: (In thousands) 2017 $ 94 2018 94 Total $ 188

Subsequent Events

Subsequent Events	9 Months Ended
	Sep. 30, 2017
Subsequent Events [Abstract]
Subsequent Events	L. Subsequent Events From October 1, 2017 to November 6, 2017, the Company repurchased 95,775 shares at an average price of $37.51 per share. In addition, on November 6, 2017, the Board of Directors approved a semi-annual dividend of $0.10 per share to all of its Class A and Class B shareholders paid payable on January 10, 2018 to shareholders of record on December 27, 2017. On October 3, 2017, GAMCO prepaid an additional $20 million of the GAMCO Note, reducing the principal outstanding to $50 million.

Basis of Presentation and Sig23

Basis of Presentation and Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2017
Basis of Presentation and Significant Accounting Policies [Abstract]
The Spin-off and Related Transactions	The Spin-off and Related Transactions We are a Delaware corporation that provides alternative investment management, institutional research and underwriting services. In addition, we derive investment income/(loss) from proprietary trading of cash and other assets awaiting deployment in our operating businesses. On November 30, 2015, GAMCO Investors, Inc. (“GAMCO” or “GBL”) distributed all the outstanding shares of each class of AC common stock on a pro rata one-for-one basis to the holders of each class of GAMCO’s common stock (the “Spin-off”). We conduct our investment management business through Gabelli & Company Investment Advisers, Inc. (“GCIA” f/k/a Gabelli Securities, Inc.). GCIA and its wholly-owned subsidiary, Gabelli & Partners, LLC (“Gabelli & Partners”), collectively serve as general partners or investment managers to investment funds including limited partnerships and offshore companies (collectively, “Investment Partnerships”), and separate accounts. We primarily manage assets in equity event-driven value strategies, across a range of risk and event arbitrage portfolios. The business earns management and incentive fees from its advisory assets. Management fees are largely based on a percentage of assets under management. Incentive fees are based on the percentage of the investment returns of certain clients’ portfolios. GCIA is an investment adviser registered with the Securities and Exchange Commission under the Investment Advisers Act of 1940, as amended. We provide our institutional research and underwriting services through G.research, LLC (“G.research”) doing business as “Gabelli & Company”, an indirect wholly-owned subsidiary of the Company. G.research is a broker-dealer registered under the Securities Exchange Act of 1934, as amended (the “Exchange Act”) and is regulated by the Financial Industry Regulatory Authority (“FINRA”). G.research's revenues are derived primarily from institutional research services. In connection with the Spin-off, GAMCO issued a promissory note (the “GAMCO Note”) to AC Group in the original principal amount of $250 million used to partially capitalize the Company. The GAMCO Note bears interest at 4% per annum and has a maturity date of November 30, 2020 with respect to its original principal amount. Interest on the GAMCO Note will accrue from the most recent date for which interest has been paid. Prior to November 30, 2019, at the election of GAMCO, payment of interest on the GAMCO Note may, in lieu of being paid in cash, be paid, in whole or in part, in kind (a “PIK Amount”). GAMCO will repay all PIK Amounts added to the outstanding principal amount of the GAMCO Note, in cash, on the fifth anniversary of the date on which each such PIK Amount was added to the outstanding principal amount of the GAMCO Note. GAMCO may prepay the GAMCO Note prior to maturity without penalty. AC has received principal repayments totaling $180 million on the GAMCO Note, of which $10 million was received during the three months ended September 30, 2017 leaving an outstanding principal balance of $70 million. After application of the principal payments, $20 million and $50 million are due on November 30, 2019 and November 30, 2020, respectively. In addition, GCIA GCIA the GCIA Note is now an intercompany obligation within the AC Group.
Basis of Presentation	Basis of Presentation The unaudited interim condensed consolidated financial statements of AC Group included herein have been prepared in conformity with accounting principles generally accepted in the United States of America (“GAAP”) for interim financial information and with the instructions to Form 10-Q and Rule 10-01 of Regulation S-X. Accordingly, they do not include all the information and footnotes required by GAAP in the United States for complete financial statements. In the opinion of management, the unaudited interim condensed consolidated financial statements reflect all adjustments, which are of a normal recurring nature, necessary for a fair presentation of financial position, results of operations and cash flows of the Company for the interim periods presented and are not necessarily indicative of a full year’s results. The interim condensed consolidated financial statements include the accounts of AC Group and its subsidiaries. Intercompany accounts and transactions are eliminated. These interim condensed consolidated financial statements should be read in conjunction with our audited consolidated financial statements included in our Annual Report on Form 10-K for the year ended December 31, 2016.
Use of Estimates	Use of Estimates The preparation of the condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported on the condensed consolidated financial statements and accompanying notes. Actual results could differ from those estimates.
Reclassification	Reclassification The Company has reclassified certain prior-period amounts to conform to the current-period presentation. For presentation of 2017 results, the Company reported revenue from its research services agreement with GAMCO in “Institutional Research Services Revenue” instead of “Other Revenue”. The reclassification did not impact revenue, operating expenses, operating income, net income, or equity.
Recent Accounting Developments	Recent Accounting Developments On May 10, 2017, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2017-09, which amends the scope of modification accounting for share-based payment arrangements. The ASU provides guidance on the types of changes to the terms or conditions of share-based payment awards to which an entity would be required to apply modification accounting under ASC 718. Specifically, an entity would not apply modification accounting if the fair value, vesting conditions, and classification of the awards are the same immediately before and after the modification. For all entities, the ASU is effective for annual reporting periods, including interim periods within those annual reporting periods, beginning after December 15, 2017. Early adoption is permitted, including adoption in any interim period. This ASU, which we did not early adopt, nonetheless would not have impacted the accounting for the acceleration of vesting of restricted stock awards (“RSAs”) during the nine months ended September 30, 2017. In March 2016, the FASB issued ASU 2016-09, which simplifies several aspects of the accounting for employee share-based payment transactions for both public and nonpublic entities, including the accounting for income taxes, forfeitures, and statutory tax withholding requirements, as well as classification in the statement of cash flows. For public companies, the ASU is effective for annual reporting periods beginning after December 15, 2016, including interim periods within those annual reporting periods. The Company adopted this ASU effective January 1, 2017 and applied this standard during the nine months ended September 30, 2017 in relation to an acceleration of vesting of RSAs during the period. In May 2014, the FASB issued ASU No. 2014-09, Revenue from Contracts with Customers, which supersedes the revenue recognition requirements in the Accounting Standards Codification (“Codification”) Topic 605, Revenue Recognition, and most industry-specific guidance throughout the industry topics of the Codification. The core principle of the new ASU No. 2014-09 is for companies to recognize revenue from the transfer of goods or services to customers in amounts that reflect the consideration to which the company expects to be entitled in exchange for those goods or services. The new standard provides a five-step approach to be applied to all contracts with customers and also requires expanded disclosures about revenue recognition. In March 2016, the FASB issued revised guidance which clarifies the guidance related to (a) determining the appropriate unit of account under the revenue standard’s principal versus agent guidance and (b) applying the indicators of whether an entity is a principal or an agent in accordance with the revenue standard’s control principle. In April 2016, the FASB issued an amendment to provide more detailed guidance including additional implementation guidance and examples related to (a) identifying performance obligations and (b) licenses of intellectual property. In May 2016, the FASB amended the standard to clarify the guidance on assessing collectability, presenting sales taxes, measuring noncash consideration, and certain transition matters. This new guidance will be effective for the Company's first quarter of 2018 and requires either a full retrospective or a modified retrospective approach to adoption. The Company’s implementation analysis is ongoing; however, it does not expect the adoption of the guidance to have a significant effect on the timing of the recognition of revenue. The Company is currently evaluating performance obligations and the related transaction costs. The Company is also reviewing and preparing for the enhanced disclosure requirements of the standard. The overall effect upon adoption may change based on further analysis and implementation efforts. The Company has not yet determined which transition method it will use. In January 2016, the FASB issued ASU 2016-01, which amends the guidance in GAAP on the classification and measurement of financial instruments. Although the ASU retains many current requirements, it significantly revises an entity’s accounting related to (a) the classification and measurement of investments in equity securities and (b) the presentation of certain fair value changes for financial liabilities measured at fair value. The ASU also amends certain disclosure requirements associated with the fair value of financial instruments. For public companies, the new standard is effective for fiscal years and interim periods within those fiscal years beginning after December 15, 2017. To adopt the amendments, entities will be required to make a cumulative-effect adjustment to beginning retained earnings as of the beginning of the fiscal year in which the guidance is effective. The Company is currently evaluating this guidance and the impact it will have on its condensed consolidated financial statements. In August 2016, the FASB issued ASU 2016-15, which adds and clarifies guidance on the classification of certain cash receipts and payments in the consolidated statements of cash flows. For public companies, the ASU is effective for annual reporting periods beginning after December 15, 2017, including interim periods within those annual reporting periods. Early adoption is permitted. The Company is currently evaluating this guidance and the impact it will have on its condensed consolidated financial statements. In January 2017, the FASB issued ASU 2017-04 to simplify the process used to test for goodwill. Under the new standard, if “the carrying amount of a reporting unit exceeds its fair value, an impairment loss shall be recognized in an amount equal to that excess, limited to the total amount of goodwill allocated to that reporting unit.” For public companies, the ASU is effective for annual and any interim impairment tests for periods beginning after December 15, 2019. Early adoption is permitted for impairment tests that occur after January 1, 2017. The Company is currently evaluating this guidance and the impact it will have on its condensed consolidated financial statements.

Investment in Securities (Table

Investment in Securities (Tables)	9 Months Ended
	Sep. 30, 2017
Investment in Securities [Abstract]
Investments in Securities	Management determines the appropriate classification of debt and equity securities at the time of purchase and reevaluates such designation as of the date of each consolidated statement of financial condition. Investments in United States Treasury Bills and Notes with maturities of greater than three months at the time of purchase are classified as investments in securities, and those with maturities of three months or less at the time of purchase are classified as cash equivalents. The portion of investments in securities held for resale in anticipation of short-term market movements are classified as trading securities. Trading securities are stated at fair value, with any unrealized gains or losses reported in current period earnings. Available for sale (“AFS”) investments are stated at fair value, with any unrealized gains or losses, net of taxes, reported as a component of equity except for losses deemed to be other-than- temporary (“OTT”) which are recorded as realized losses in the condensed consolidated statements of income. In addition, realized gains and losses from AFS securities are reclassified from equity to current period income. Investments in securities, including GBL stock, at September 30, 2017, December 31, 2016 and September 30, 2016 consisted of the following: September 30, 2017 December 31, 2016 September 30, 2016 Cost Fair Value Cost Fair Value Cost Fair Value (In thousands) Trading securities: Government obligations $ 115,897 $ 116,152 $ 119,755 $ 119,823 $ 24,952 $ 24,995 Common stocks 155,732 172,312 69,503 82,158 64,393 77,031 Mutual funds 2,405 3,633 2,402 3,143 2,384 3,031 Other investments 1,378 1,491 1,275 1,472 696 934 Total trading securities 275,412 293,588 192,935 206,596 92,425 105,991 Available for sale securities: Common stocks 130,869 130,737 150,000 135,701 150,000 125,070 Mutual funds 103 284 206 500 206 481 Total available for sale securities 130,972 131,021 150,206 136,201 150,206 125,551 Total investments in securities $ 406,384 $ 424,609 $ 343,141 $ 342,797 $ 242,631 $ 231,542
Securities Sold, Not Yet Purchased	Securities sold, not yet purchased at September 30, 2017, December 31, 2016 and September 30, 2016 consisted of the following: September 30, 2017 December 31, 2016 September 30, 2016 Proceeds Fair Value Proceeds Fair Value Proceeds Fair Value Trading securities: (In thousands) Common stocks $ 7,906 $ 8,558 $ 9,583 $ 9,947 $ 3,697 $ 3,948 Other investments 1 501 27 37 245 267 Total securities sold, not yet purchased $ 7,907 $ 9,059 $ 9,610 $ 9,984 $ 3,942 $ 4,215
Investments in Affiliated Registered Investment Companies	Investments in affiliated registered investment companies at September 30, 2017, December 31, 2016 and September 30, 2016 consisted of the following: September 30, 2017 December 31, 2016 September 30, 2016 Cost Fair Value Cost Fair Value Cost Fair Value (In thousands) Trading securities: Mutual funds $ 40,095 $ 46,390 $ 40,096 $ 45,351 $ 40,096 $ 44,799 Total trading securities 40,095 46,390 40,096 45,351 40,096 44,799 Available for sale securities: Closed-end funds 65,180 90,516 62,890 80,650 61,375 75,392 Mutual funds 4,384 6,159 4,396 5,644 4,408 6,031 Total available for sale securities 69,564 96,675 67,286 86,294 65,783 81,423 Total investments in affiliated registered investment companies $ 109,659 $ 143,065 $ 107,382 $ 131,645 $ 105,879 $ 126,222
Reclassifications Out of Accumulated Other Comprehensive Income (Loss)	The following table identifies all reclassifications out of accumulated other comprehensive income (“AOCI”) into income for the three and nine months ended September 30, 2017 and 2016 (in thousands): Amount Affected Line Items Reason for Reclassified in the Statements Reclassification from AOCI Of Income from AOCI Three months ended September 30, 2017 2016 $ 125 $ - Net gain/(loss) from investments Realized gain on sale of AFS securities 125 - Income/(loss) before income taxes (45 ) - Income tax provision $ 80 $ - Net income/(loss) Amount Affected Line Items Reason for Reclassified in the Statements Reclassification from AOCI Of Income from AOCI Nine months ended September 30, 2017 2016 $ 167 $ 348 Net gain/(loss) from investments Realized gain on sale of AFS securities (19,131 ) (298 ) Net gain/(loss) from investments OTT impairment of AFS securities (18,964 ) 50 Income/(loss) before income taxes 6,827 (18 ) Income tax provision $ (12,137 ) $ 32 Net income/(loss)
Schedule of Fair Values and Gains and Losses of All Derivatives and Foreign Currency Positions	The following table identifies the fair values of all derivatives held by the Company (in thousands): Asset Derivatives Liability Derivatives Statement of Fair Value Statement of Fair Value Financial Condition September 30, December 31, September 30, Financial Condition September 30, December 31, September 30, Location 2017 2016 2016 Location 2017 2016 2016 Derivatives designated as hedging instruments under FASB ASC 815-20 Foreign exchange Receivable from contracts brokers $ - $ - $ - Payable to brokers $ - $ - $ - Sub total $ - $ - $ - $ - $ - $ - Derivatives not designated as hedging instruments under FASB ASC 815-20 Equity contracts Investments in Securities sold, securities $ 151 $ 127 $ 178 not yet purchased $ 501 $ 37 $ 33 Foreign exchange Receivable from contracts brokers - - - Payable to brokers - - - Sub total $ 151 $ 127 $ 178 $ 501 $ 37 $ 33 Total derivatives $ 151 $ 127 $ 178 $ 501 $ 37 $ 33
Schedule of Derivative Instruments, Gain (Loss)	The following table identifies gains and losses of all derivatives held by the Company (in thousands): Type of Derivative Income Statement Location Three Months Ended September 30, Nine Months Ended September 30, 2017 2016 2017 2016 Foreign exchange contracts Net gain/(loss) from investments $ - $ - $ - $ 1,373 Equity contracts Net gain/(loss) from investments (456 ) 159 (490 ) 204 Total $ (456 ) $ 159 $ (490 ) $ 1,577
Master Netting Arrangements for Swaps	The Company is a party to enforceable master netting arrangements for swaps entered into with major U.S. financial institutions as part of the investment strategy of the Company’s proprietary portfolio. They are typically not used as hedging instruments. These swaps, while settled on a net basis with the counterparties are shown gross in assets and liabilities on the condensed consolidated statements of financial condition. The swaps have a firm contract end date and are closed out and settled when each contract expires. Gross Amounts Not Offset in the Statements of Financial Condition Gross Gross Amounts Net Amounts of Amounts of Offset in the Assets Presented Recognized Statements of in the Statements of Financial Cash Collateral Assets Financial Condition Financial Condition Instruments Received Net Amount Swaps: (In thousands) September 30, 2017 $ 151 $ - $ 151 $ (151 ) $ - $ - December 31, 2016 96 - 96 (9 ) - 87 September 30, 2016 $ 178 $ - $ 178 $ (14 ) $ - $ 164 Gross Amounts Not Offset in the Statements of Financial Condition Gross Gross Amounts Net Amounts of Amounts of Offset in the Liabilities Presented Recognized Statements of in the Statements of Financial Cash Collateral Liabilities Financial Condition Financial Condition Instruments Pledged Net Amount Swaps: (In thousands) September 30, 2017 $ 500 $ - $ 500 $ (151 ) $ - $ 349 December 31, 2016 9 - 9 (9 ) - - September 30, 2016 $ 14 $ - $ 14 $ (14 ) $ - $ -
Summary of Available-for-Sale Securities	The following is a summary of the cost, gross unrealized gains, gross unrealized losses and fair value of available for sale investments as of September 30, 2017, December 31, 2016 and September 30, 2016: September 30, 2017 Gross Gross Unrealized Unrealized Cost Gains Losses Fair Value (In thousands) Common stocks $ 130,869 $ - $ (132 ) $ 130,737 Closed-end funds 65,180 25,535 (199 ) 90,516 Mutual funds 4,487 1,956 - 6,443 Total available for sale securities $ 200,536 $ 27,491 $ (331 ) $ 227,696 December 31, 2016 Gross Gross Unrealized Unrealized Cost Gains Losses Fair Value (In thousands) Common stocks $ 150,000 $ - $ (14,299 ) $ 135,701 Closed-end funds 62,890 17,760 - 80,650 Mutual funds 4,602 1,542 - 6,144 Total available for sale securities $ 217,492 $ 19,302 $ (14,299 ) $ 222,495 September 30, 2016 Gross Gross Unrealized Unrealized Cost Gains Losses Fair Value (In thousands) Common stocks $ 150,000 $ - $ (24,930 ) $ 125,070 Closed-end funds 61,375 14,027 (10 ) 75,392 Mutual funds 4,614 1,898 - 6,512 Total available for sale securities $ 215,989 $ 15,925 $ (24,940 ) $ 206,974
Investments Classified as Available for Sale in Unrealized Loss Position	Investments classified as available for sale that are in an unrealized loss position for which other-than-temporary impairment has not been recognized consisted of the following (in thousands): September 30, 2017 December 31, 2016 September 30, 2016 Unrealized Unrealized Unrealized Cost Losses Fair Value Cost Losses Fair Value Cost Losses Fair Value Common stocks $ 130,869 $ (132 ) $ 130,737 $ 150,000 $ (14,299 ) $ 135,701 $ 150,000 $ (24,930 ) $ 125,070 Closed-end funds 1,864 (199 ) 1,665 - - - 3,162 (10 ) 3,152 Total available for sale securities in unrealized loss position $ 132,733 $ (331 ) $ 132,402 $ 150,000 $ (14,299 ) $ 135,701 $ 153,162 $ (24,940 ) $ 128,222

Fair Value (Tables)

Fair Value (Tables)	9 Months Ended
	Sep. 30, 2017
Fair Value [Abstract]
Assets and Liabilities Measured at Fair Value on a Recurring Basis	The following tables present information about the Company’s assets and liabilities by major category measured at fair value on a recurring basis as of September 30, 2017, December 31, 2016 and September 30, 2016 and indicates the fair value hierarchy of the valuation techniques utilized by the Company to determine such fair value. Investments in certain entities that calculate net asset value per share and other investments that are not held at fair value are provided as separate items to permit reconciliation of the fair value of investments included in the fair value hierarchy to the total amounts presented in the condensed consolidated statements of financial condition. Assets and Liabilities Measured at Fair Value on a Recurring Basis as of September 30, 2017 (in thousands) Quoted Prices in Active Significant Other Significant Investments Other Assets Balance as of Markets for Identical Observable Unobservable Measured at Not Held at September 30, Assets Assets (Level 1) Inputs (Level 2) Inputs (Level 3) NAV (a) Fair Value (b) 2017 Cash equivalents $ 240,727 $ - $ - $ - $ - $ 240,727 Investments in partnerships - - - 138,035 3,059 141,094 Investments in securities (including GBL stock): AFS - Common stocks 130,737 - - - - 130,737 AFS - Mutual funds 284 - - - - 284 Trading - Gov't obligations 116,152 - - - - 116,152 Trading - Common stocks 171,835 1 476 - - 172,312 Trading - Mutual funds 3,633 - - - - 3,633 Trading - Other 994 151 346 - - 1,491 Total investments in securities 423,635 152 822 - - 424,609 Investments in affiliated registered investment companies: AFS - Closed-end funds 90,516 - - - - 90,516 AFS - Mutual funds 6,159 - - - - 6,159 Trading - Mutual funds 46,390 - - - - 46,390 Total investments in affiliated registered investment companies 143,065 - - - - 143,065 Total investments 566,700 152 822 138,035 3,059 708,768 Total assets at fair value $ 807,427 $ 152 $ 822 $ 138,035 $ 3,059 $ 949,495 Liabilities Trading - Common stocks $ 8,558 $ - $ - $ - $ - $ 8,558 Trading - Other - 501 - - - 501 Securities sold, not yet purchased $ 8,558 $ 501 $ - $ - $ - $ 9,059 Assets and Liabilities Measured at Fair Value on a Recurring Basis as of December 31, 2016 (in thousands) Quoted Prices in Active Significant Other Significant Investments Other Assets Balance as of Markets for Identical Observable Unobservable Measured at Not Held at December 31, Assets Assets (Level 1) Inputs (Level 2) Inputs (Level 3) NAV (a) Fair Value (b) 2016 Cash equivalents $ 314,082 $ - $ - $ - $ - $ 314,082 Investments in partnerships - - - 125,527 3,871 129,398 Investments in securities (including GBL stock): AFS - Common stocks 135,701 - - - - 135,701 AFS - Mutual funds 500 - - - - 500 Trading - Gov't obligations 119,823 - - - - 119,823 Trading - Common stocks 81,696 1 461 - - 82,158 Trading - Mutual funds 3,143 - - - - 3,143 Trading - Other 1,062 127 283 - - 1,472 Total investments in securities 341,925 128 744 - - 342,797 Investments in affiliated registered investment companies: AFS - Closed-end funds 80,650 - - - - 80,650 AFS - Mutual funds 5,644 - - - - 5,644 Trading - Mutual funds 45,351 - - - - 45,351 Total investments in affiliated registered investment companies 131,645 - - - - 131,645 Total investments 473,570 128 744 125,527 3,871 603,840 Total assets at fair value $ 787,652 $ 128 $ 744 $ 125,527 $ 3,871 $ 917,922 Liabilities Trading - Common stocks $ 9,947 $ - $ - $ - $ - $ 9,947 Trading - Other - 37 - - - 37 Securities sold, not yet purchased $ 9,947 $ 37 $ - $ - $ - $ 9,984 Assets and Liabilities Measured at Fair Value on a Recurring Basis as of September 30, 2016 (in thousands) Quoted Prices in Active Significant Other Significant Investments Other Assets Balance as of Markets for Identical Observable Unobservable Measured at Not Held at September 30, Assets Assets (Level 1) Inputs (Level 2) Inputs (Level 3) NAV (a) Fair Value (b) 2016 Cash equivalents $ 402,391 $ - $ - $ - $ - $ 402,391 Investments in partnerships - - - 125,977 2,221 128,198 Investments in securities (including GBL stock): AFS - Common stocks 125,070 - - - - 125,070 AFS - Mutual funds 481 - - - - 481 Trading - Gov't obligations 24,995 - - - - 24,995 Trading - Common stocks 76,570 - 461 - - 77,031 Trading - Mutual funds 3,031 - - - - 3,031 Trading - Other 476 178 280 - - 934 Total investments in securities 230,623 178 741 - - 231,542 Investments in affiliated registered investment companies: AFS - Closed-end funds 72,240 3,152 - - - 75,392 AFS - Mutual funds 6,031 - - - - 6,031 Trading - Mutual funds 44,799 - - - - 44,799 Total investments in affiliated registered investment companies 123,070 3,152 - - - 126,222 Total investments 353,693 3,330 741 125,977 2,221 485,962 Total assets at fair value $ 756,084 $ 3,330 $ 741 $ 125,977 $ 2,221 $ 888,353 Liabilities Trading - Common stocks $ 3,948 $ - $ - $ - $ - $ 3,948 Trading - Other - 267 - - - 267 Securities sold, not yet purchased $ 3,948 $ 267 $ - $ - $ - $ 4,215 (a) Includes certain investments measured at fair value using NAV (or its equivalent) as a practical expedient. These investments have not been classified in the fair value hierarchy. (b) Includes certain equity method investments which are not accounted for under a fair value measure. In accordance with GAAP, certain equity method investees do not account for their financial assets and liabilities under fair value measures; therefore, the Company’s investment in such equity method investees may not represent fair value. The following tables present additional information about assets by major category measured at fair value on a recurring basis and for which the Company has utilized Level 3 inputs to determine fair value:
Changes in Level 3 Assets and Liabilities	Changes in Level 3 Assets and Liabilities Measured at Fair Value on a Recurring Basis for the Three Months Ended September 30, 2017 (in thousands) Total Unrealized Gains or Total Total Realized and (Losses) Realized June 30, Unrealized Gains or Included in and Transfers September 30, 2017 (Losses) in Income Other Unrealized In and/or 2017 Beginning AFS Comprehensive Gains or (Out) of Ending Asset Balance Trading Investments Income (Losses) Purchases Sales Level 3 Balance Financial instruments owned: Trading - Common stocks $ 510 $ 2 $ - $ - $ 2 $ - $ - $ (36 ) $ 476 Trading - Other 449 39 - - 39 - (142 ) - 346 Total $ 959 $ 41 $ - $ - $ 41 - $ (142 ) $ (36 ) $ 822 There were no transfers between Level 1 and Level 2 during the three months ended September 30, 2017. During the three months ended September 30, 2017, the Company transferred an investment with a value of approximately $36,000 from Level 3 to Level 1. The reclassification was due to increased availability of market price quotations and was based on the value at the beginning of the period in which the transfer occurred. Changes in Level 3 Assets and Liabilities Measured at Fair Value on a Recurring Basis for the Three Months Ended September 30, 2016 (in thousands) Total Unrealized Gains or Total Total Realized and (Losses) Realized June 30, Unrealized Gains or Included in and Transfers September 30, 2016 (Losses) in Income Other Unrealized In and/or 2016 Beginning AFS Comprehensive Gains or (Out) of Ending Asset Balance Trading Investments Income (Losses) Purchases Sales Level 3 Balance Financial instruments owned: Trading - Common stocks $ 502 $ (41 ) $ - $ - $ (41 ) $ - $ - $ - $ 461 Trading - Other 296 4 - - 4 - (20 ) - 280 Total $ 798 $ (37 ) $ - $ - $ (37 ) $ - $ (20 ) $ - $ 741 There were no transfers between any Levels during the three months ended September 30, 2016. Changes in Level 3 Assets and Liabilities Measured at Fair Value on a Recurring Basis for the Nine Months Ended September 30, 2017 (in thousands) Total Unrealized Gains or Total Total Realized and (Losses) Realized December 31, Unrealized Gains or Included in and Transfers September 30, 2016 (Losses) in Income Other Unrealized In and/or 2017 Beginning AFS Comprehensive Gains or (Out) of Ending Asset Balance Trading Investments Income (Losses) Purchases Sales Level 3 Balance Financial instruments owned: Trading - Common stocks $ 461 $ 51 $ - $ - $ 51 $ - $ - $ (36 ) $ 476 Trading - Other 283 46 - - 46 167 (150 ) - 346 Total $ 744 $ 97 $ - $ - $ 97 $ 167 $ (150 ) $ (36 ) $ 822 There were no transfers between Level 1 and Level 2 during the nine months ended September 30, 2017. During the nine months ended September 30, 2017, the Company transferred an investment with a value of approximately $36,000 from Level 3 to Level 1. The reclassification was due to increased availability of market price quotations and was based on the value at the beginning of the period in which the transfer occurred. Changes in Level 3 Assets and Liabilities Measured at Fair Value on a Recurring Basis for the Nine Months Ended September 30, 2016 (in thousands) Total Unrealized Gains or Total Total Realized and (Losses) Realized December 31, Unrealized Gains or Included in and Transfers September 30, 2015 (Losses) in Income Other Unrealized In and/or 2016 Beginning AFS Comprehensive Gains or (Out) of Ending Asset Balance Trading Investments Income (Losses) Purchases Sales Level 3 Balance Financial instruments owned: Trading - Common stocks $ 508 $ (47 ) $ - $ - $ (47 ) $ - $ - $ - $ 461 Trading - Other 305 (5 ) - - (5 ) - (20 ) - 280 Total $ 813 $ (52 ) $ - $ - $ (52 ) $ - $ (20 ) $ - $ 741 There were no transfers between any Levels during the nine months ended September 30, 2016.

Investments in Partnerships, 26

Investments in Partnerships, Offshore Funds and Variable Interest Entities ("VIEs") (Tables)	9 Months Ended
	Sep. 30, 2017
Investments in Partnerships, Offshore Funds and Variable Interest Entities ("VIEs") [Abstract]
Schedule of Number of Entities Consolidated	The following table highlights the number of entities that we consolidate as well as the basis under which they are consolidated: Entities consolidated CFFs Partnerships Offshore Funds Total VIEs VOEs VIEs VOEs VIEs VOEs VIEs VOEs Entities consolidated at December 31, 2015 1 2 - 2 1 - 2 4 Additional consolidated entities - - 1 - - - 1 - Deconsolidated entities (1) (1) - (2) (1) - (2) (3) Entities consolidated at September 30, 2016 - 1 1 - - - 1 1 Additional consolidated entities - - - - - - - - Deconsolidated entities - - - - - - - - Entities consolidated at December 31, 2016 - 1 1 - - - 1 1 Additional consolidated entities - - - - - 1 - 1 Deconsolidated entities - - - - - - - - Entities consolidated at September 30, 2017 - 1 1 - - 1 1 2
Investment in Partnerships by Accounting Method	The following table provides details of our investments in partnerships by the accounting method used and investment type (in thousands): September 30, 2017 Investment Type Affiliated Unaffiliated Consolidated Accounting method Feeder Funds Partnerships Offshore Funds Partnerships Offshore Funds Total Fair Value $ 8,297 $ - $ - $ - $ - $ 8,297 Equity Method - 41,169 73,146 6,104 12,378 132,797 Total $ 8,297 $ 41,169 $ 73,146 $ 6,104 $ 12,378 $ 141,094 December 31, 2016 Investment Type Affiliated Unaffiliated Consolidated Accounting method Feeder Funds Partnerships Offshore Funds Partnerships Offshore Funds Total Fair Value $ 8,343 $ - $ - $ - $ - $ 8,343 Equity Method - 33,202 70,745 6,761 10,347 121,055 Total $ 8,343 $ 33,202 $ 70,745 $ 6,761 $ 10,347 $ 129,398 September 30, 2016 Investment Type Affiliated Unaffiliated Consolidated Accounting method Feeder Funds Partnerships Offshore Funds Partnerships Offshore Funds Total Fair Value $ 8,123 $ - $ - $ - $ - $ 8,123 Equity Method - 40,516 64,810 5,438 9,311 120,075 Total $ 8,123 $ 40,516 $ 64,810 $ 5,438 $ 9,311 $ 128,198
Condensed Consolidated Statements of Financial Condition by Entity Consolidated	The following table includes the net impact by line item on the condensed consolidated statements of financial condition for each category of consolidated entity (in thousands): September 30, 2017 Prior to Offshore Consolidation CFFs Partnerships Funds As Reported Assets Cash and cash equivalents $ 234,124 $ - $ 119 $ 8,059 $ 242,302 Investments in securities (including GBL stock) 320,021 - 6,948 97,640 424,609 Investments in affiliated investment companies 195,401 - - (52,336 ) 143,065 Investments in partnerships 155,462 3,803 (8,936 ) (9,235 ) 141,094 Receivable from brokers 8,208 - 2,217 5,328 15,753 Investment advisory fees receivable 1,445 (4 ) (8 ) - 1,433 Other assets 11,163 - - 100 11,263 Total assets $ 925,824 $ 3,799 $ 340 $ 49,556 $ 979,519 Liabilities and equity Securities sold, not yet purchased $ 8,585 $ - $ - $ 474 $ 9,059 Accrued expenses and other liabilities 19,031 15 28 11,059 30,133 Redeemable noncontrolling interests - 3,784 312 38,023 42,119 Total equity 898,208 - - - 898,208 Total liabilities and equity $ 925,824 $ 3,799 $ 340 $ 49,556 $ 979,519 December 31, 2016 Prior to Offshore Consolidation CFFs Partnerships Funds As Reported Assets Cash and cash equivalents $ 313,785 $ - $ 308 $ - $ 314,093 Investments in securities (including GBL stock) 336,459 - 6,338 - 342,797 Investments in affiliated investment companies 131,645 - - - 131,645 Investments in partnerships 133,794 3,964 (8,360 ) - 129,398 Receivable from brokers 10,542 - 2,046 - 12,588 Investment advisory fees receivable 9,800 (8 ) (8 ) - 9,784 Other assets 12,298 - - - 12,298 Total assets $ 948,323 $ 3,956 $ 324 $ - $ 952,603 Liabilities and equity Securities sold, not yet purchased $ 9,984 $ - $ - $ - $ 9,984 Accrued expenses and other liabilities 64,317 13 37 - 64,367 Redeemable noncontrolling interests - 3,943 287 - 4,230 Total equity 874,022 - - - 874,022 Total liabilities and equity $ 948,323 $ 3,956 $ 324 $ - $ 952,603 September 30, 2016 Prior to Offshore Consolidation CFFs Partnerships Funds As Reported Assets Cash and cash equivalents $ 402,395 $ - $ 8 $ - $ 402,403 Investments in securities (including GBL stock) 224,996 - 6,546 - 231,542 Investments in affiliated investment companies 126,222 - - - 126,222 Investments in partnerships 132,564 3,730 (8,096 ) - 128,198 Receivable from brokers 17,943 - 1,864 - 19,807 Investment advisory fees receivable 1,944 (7 ) (5 ) - 1,932 Other assets 14,707 - - - 14,707 Total assets $ 920,771 $ 3,723 $ 317 $ - $ 924,811 Liabilities and equity Securities sold, not yet purchased $ 4,215 $ - $ - $ - $ 4,215 Accrued expenses and other liabilities 18,487 11 30 - 18,528 Redeemable noncontrolling interests - 3,712 287 - 3,999 Total equity 898,069 - - - 898,069 Total liabilities and equity $ 920,771 $ 3,723 $ 317 $ - $ 924,811
Condensed Consolidated Statements of Income by Entity Consolidated	The following table includes the net impact by line item on the condensed consolidated statements of income for each category of consolidated entity (in thousands): Three Months Ended September 30, 2017 Prior to Offshore Consolidation CFFs Partnerships Funds As Reported Total revenues $ 5,252 $ (4 ) $ - $ - $ 5,248 Total expenses 10,188 28 11 1,133 11,360 Operating loss (4,936 ) (32 ) (11 ) (1,133 ) (6,112 ) Total other income, net 6,522 32 22 936 7,512 Income (loss) before income taxes 1,586 - 11 (197 ) 1,400 Income tax provision 67 - - - 67 Net income (loss) 1,519 - 11 (197 ) 1,333 Net income (loss) attributable to noncontrolling interests - - 11 (197 ) (186 ) Net income attributable to AC Group $ 1,519 $ - $ - $ - $ 1,519 Three Months Ended September 30, 2016 Prior to Offshore Consolidation CFFs Partnerships Funds As Reported Total revenues $ 5,456 $ (4 ) $ (1 ) $ - $ 5,451 Total expenses 9,910 29 9 - 9,948 Operating loss (4,454 ) (33 ) (10 ) - (4,497 ) Total other income, net 10,220 110 3 - 10,333 Income (loss) before income taxes 5,766 77 (7 ) - 5,836 Income tax provision 1,807 - - - 1,807 Net income (loss) 3,959 77 (7 ) - 4,029 Net income (loss) attributable to noncontrolling interests - 77 (7 ) - 70 Net income attributable to AC Group $ 3,959 $ - $ - $ - $ 3,959 Nine Months Ended September 30, 2017 Prior to Offshore Consolidation CFFs Partnerships Funds As Reported Total revenues $ 15,345 $ (13 ) $ (2 ) $ - $ 15,330 Total expenses 30,959 103 32 1,133 32,227 Operating loss (15,614 ) (116 ) (34 ) (1,133 ) (16,897 ) Total other income (expense), net (16 ) 191 61 936 1,172 Income (loss) before income taxes (15,630 ) 75 27 (197 ) (15,725 ) Income tax provision (8,667 ) - - - (8,667 ) Net income (loss) (6,963 ) 75 27 (197 ) (7,058 ) Net income (loss) attributable to noncontrolling interests - 75 27 (197 ) (95 ) Net loss attributable to AC Group $ (6,963 ) $ - $ - $ - $ (6,963 ) Nine Months Ended September 30, 2016 Prior to Offshore Consolidation CFFs Partnerships Funds As Reported Total revenues $ 14,946 $ (12 ) $ (2 ) $ - $ 14,932 Total expenses 27,170 91 35 - 27,296 Operating loss (12,224 ) (103 ) (37 ) - (12,364 ) Total other income, net 21,522 414 42 - 21,978 Income before income taxes 9,298 311 5 - 9,614 Income tax provision 2,773 - - - 2,773 Net income 6,525 311 5 - 6,841 Net income (loss) attributable to noncontrolling interests (46 ) 311 5 - 270 Net income attributable to AC Group $ 6,571 $ - $ - $ - $ 6,571
Balances Related to VIEs And AC's Net Interests in Consolidated VIE	The following table presents the balances of the VIE that is consolidated at September 30, 2017, December 31, 2016 and September 30, 2016 and included on the condensed consolidated statements of financial condition as well as AC Group’s net interest in the VIE: September 30, December 31, September 30, 2017 2016 2016 (In thousands) Cash and cash equivalents $ 119 $ 308 $ 8 Investments in securities 6,948 6,338 6,546 Receivable from brokers 2,217 2,046 1,864 Other assets (8 ) (8 ) (5 ) Accrued expenses and other liabilities (28 ) (37 ) (29 ) Redeemable noncontrolling interests (312 ) (287 ) (288 ) AC Group's net interests in consolidated VIE $ 8,936 $ 8,360 $ 8,096

Earnings Per Share (Tables)

Earnings Per Share (Tables)	9 Months Ended
	Sep. 30, 2017
Earnings Per Share [Abstract]
Computations of Basic and Diluted Net Income/(Loss) Per Share	The computations of basic and diluted net income/(loss) per share are as follows: Three Months Ended September 30, (in thousands, except per share amounts) 2017 2016 Basic: Net income attributable to Associated Capital Group, Inc.'s shareholders $ 1,519 $ 3,959 Weighted average shares outstanding 23,841 24,918 Basic net income attributable to Associated Capital Group, Inc.'s shareholders per share $ 0.06 $ 0.16 Diluted: Net income attributable to Associated Capital Group, Inc.'s shareholders $ 1,519 $ 3,959 Weighted average share outstanding 23,841 24,918 Dilutive restricted stock awards - 301 Total 23,841 25,219 Diluted net income attributable to Associated Capital Group, Inc.'s shareholders per share $ 0.06 $ 0.16 Nine Months Ended September 30, 2017 2016 Basic: Net income/(loss) attributable to Associated Capital Group, Inc.'s shareholders $ (6,963 ) $ 6,571 Weighted average shares outstanding 23,826 24,879 Basic net income/(loss) atttributable to Associated Capital Group, Inc.'s shareholders per share $ (0.29 ) $ 0.26 Diluted: Net income/(loss) attributable to Associated Capital Group, Inc.'s shareholders $ (6,963 ) $ 6,571 Weighted average shares outstanding 23,826 24,879 Dilutive restricted stock awards - 315 Total 23,826 25,194 Diluted net income/(loss) attributable to Associated Capital Group, Inc.'s shareholders per share $ (0.29 ) $ 0.26

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	9 Months Ended
	Sep. 30, 2017
Stockholders' Equity [Abstract]
Actual and Projected Stock-Based Compensation Expense for RSA Shares	For the three months ended September 30, 2017 and September 30, 2016, we recognized stock-based compensation expense of $1.9 million and $0.7 million, respectively. For the nine months ended September 30, 2017 and September 30, 2016, we recognized stock-based compensation expense of $5.2 million and $2.0 million, respectively. Please note that the Company’s stock-based compensation expense also includes an allocation of GAMCO related stock-based compensation expense with respect to GAMCO teammates who provide services to the Company under our services agreements with GAMCO. Actual and projected stock-based compensation expense for RSA shares for the years ended December 31, 2016 through December 31, 2024 (based on AC and GAMCO awards currently issued or granted) is as follows (in thousands): 2016 2017 2018 2019 2020 2021 2022 2023 2024 Q1 $ 644 $ 444 $ 67 $ 56 $ 26 $ 15 $ 10 $ 5 $ 1 Q2 644 2,920 64 56 22 15 10 5 1 Q3 727 1,862 59 51 18 12 7 3 1 Q4 449 83 56 48 15 10 5 1 - Full Year $ 2,464 $ 5,309 $ 246 $ 211 $ 81 $ 52 $ 32 $ 14 $ 3

Contractual Obligations (Tables

Contractual Obligations (Tables)	9 Months Ended
	Sep. 30, 2017
Contractual Obligations [Abstract]
Future Minimum Lease Commitments under Operating Lease	In June 2016, AC entered into a sublease agreement with GAMCO effective from April 1, 2016 through March 31, 2017. The Company renewed the sublease agreement with GAMCO in March 2017 for an additional year. Future minimum lease commitments under this operating lease as of September 30, 2017 are as follows: (In thousands) 2017 $ 94 2018 94 Total $ 188

Basis of Presentation and Sig30

Basis of Presentation and Significant Accounting Policies (Details) - USD ($) $ in Millions	Nov. 30, 2015	Sep. 30, 2017	Sep. 30, 2017	Sep. 30, 2016	Mar. 31, 2017
Class of Stock [Line Items]
Number of AC shares issued for each GAMCO shares in connection with spin-off (in shares)	1
Number of AC shares exchanged (in shares)				163,428
GAMCO Note [Member]
Class of Stock [Line Items]
Notes receivable, face amount		$ 250	$ 250
Notes receivable, interest rate		4.00%	4.00%
Notes receivable, maturity date			Nov. 30, 2020
Principal repayments received		$ 10			$ 180
Notes receivable outstanding		70	$ 70
GAMCO Note [Member] | Principal Amount Due on November 30, 2019 [Member]
Class of Stock [Line Items]
Notes receivable outstanding		20	20
GAMCO Note [Member] | Principal Amount Due on November 30, 2020 [Member]
Class of Stock [Line Items]
Notes receivable outstanding		50	50
GCIA Note [Member]
Class of Stock [Line Items]
Notes receivable, face amount		$ 150	$ 150
GAMCO [Member]
Class of Stock [Line Items]
Number of GAMCO shares exchanged for each AC shares in connection with spin-off (in shares)	1
GAMCO [Member] | Class A [Member]
Class of Stock [Line Items]
Number of shares of common stock purchased (in shares)			4,393,055

Investment in Securities, Inves

Investment in Securities, Investment in Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016	Sep. 30, 2016
Available for sale securities [Abstract]
Cost	$ 200,536	$ 217,492	$ 215,989
Fair value	227,696	222,495	206,974
Total investments in securities [Abstract]
Cost	406,384	343,141	242,631
Fair value	424,609	342,797	231,542
Common Stocks [Member]
Available for sale securities [Abstract]
Cost	130,869	150,000	150,000
Fair value	130,737	135,701	125,070
Mutual Funds [Member]
Available for sale securities [Abstract]
Cost	4,487	4,602	4,614
Fair value	6,443	6,144	6,512
Investment in Securities [Member] | Trading Securities [Member]
Trading securities [Abstract]
Cost	275,412	192,935	92,425
Fair value	293,588	206,596	105,991
Investment in Securities [Member] | Trading Securities [Member] | Government Obligations [Member]
Trading securities [Abstract]
Cost	115,897	119,755	24,952
Fair value	116,152	119,823	24,995
Investment in Securities [Member] | Trading Securities [Member] | Common Stocks [Member]
Trading securities [Abstract]
Cost	155,732	69,503	64,393
Fair value	172,312	82,158	77,031
Investment in Securities [Member] | Trading Securities [Member] | Mutual Funds [Member]
Trading securities [Abstract]
Cost	2,405	2,402	2,384
Fair value	3,633	3,143	3,031
Investment in Securities [Member] | Trading Securities [Member] | Other Investments [Member]
Trading securities [Abstract]
Cost	1,378	1,275	696
Fair value	1,491	1,472	934
Investment in Securities [Member] | Available for Sale Securities [Member]
Available for sale securities [Abstract]
Cost	130,972	150,206	150,206
Fair value	131,021	136,201	125,551
Investment in Securities [Member] | Available for Sale Securities [Member] | Common Stocks [Member]
Available for sale securities [Abstract]
Cost	130,869	150,000	150,000
Fair value	130,737	135,701	125,070
Investment in Securities [Member] | Available for Sale Securities [Member] | Mutual Funds [Member]
Available for sale securities [Abstract]
Cost	103	206	206
Fair value	$ 284	$ 500	$ 481

Investment in Securities, Secur

Investment in Securities, Securities Sold, Not Yet Purchased (Details) - Investment in Securities [Member] - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016	Sep. 30, 2016
Trading securities [Abstract]
Proceeds	$ 7,907	$ 9,610	$ 3,942
Fair value	9,059	9,984	4,215
Trading Securities [Member] | Common Stocks [Member]
Trading securities [Abstract]
Proceeds	7,906	9,583	3,697
Fair value	8,558	9,947	3,948
Trading Securities [Member] | Other Investments [Member]
Trading securities [Abstract]
Proceeds	1	27	245
Fair value	$ 501	$ 37	$ 267

Investment in Securities, Inv33

Investment in Securities, Investment in Affiliated Registered Investment Companies (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016	Sep. 30, 2016
Available for sale securities [Abstract]
Cost	$ 200,536	$ 217,492	$ 215,989
Fair value	227,696	222,495	206,974
Total investments in affiliated registered investment companies [Abstract]
Cost	109,659	107,382	105,879
Fair value	143,065	131,645	126,222
Closed-end Funds [Member]
Available for sale securities [Abstract]
Cost	65,180	62,890	61,375
Fair value	90,516	80,650	75,392
Mutual Funds [Member]
Available for sale securities [Abstract]
Cost	4,487	4,602	4,614
Fair value	6,443	6,144	6,512
Investment in Affiliated Registered Investment Companies [Member] | Trading Securities [Member]
Trading securities [Abstract]
Cost	40,095	40,096	40,096
Fair value	46,390	45,351	44,799
Investment in Affiliated Registered Investment Companies [Member] | Trading Securities [Member] | Mutual Funds [Member]
Trading securities [Abstract]
Cost	40,095	40,096	40,096
Fair value	46,390	45,351	44,799
Investment in Affiliated Registered Investment Companies [Member] | Available for Sale Securities [Member]
Available for sale securities [Abstract]
Cost	69,564	67,286	65,783
Fair value	96,675	86,294	81,423
Investment in Affiliated Registered Investment Companies [Member] | Available for Sale Securities [Member] | Closed-end Funds [Member]
Available for sale securities [Abstract]
Cost	65,180	62,890	61,375
Fair value	90,516	80,650	75,392
Investment in Affiliated Registered Investment Companies [Member] | Available for Sale Securities [Member] | Mutual Funds [Member]
Available for sale securities [Abstract]
Cost	4,384	4,396	4,408
Fair value	$ 6,159	$ 5,644	$ 6,031

Investment in Securities, Recla

Investment in Securities, Reclassifications Out of Accumulated Other Comprehensive Income into Income (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017USD ($)Contractshares	Sep. 30, 2016USD ($)Contractshares	Sep. 30, 2017USD ($)Contractshares	Sep. 30, 2016USD ($)Contractshares	Dec. 31, 2016Contractshares
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net gain/(loss) from investments	$ 5,234	$ 7,566	$ (1,018)	$ 12,770
Other operating expenses	3,006	2,165	7,305	6,047
Income/(loss) before income taxes	1,400	5,836	(15,725)	9,614
Income tax provision	(67)	(1,807)	8,667	(2,773)
Net income/(loss)	$ 1,333	$ 4,029	$ (7,058)	$ 6,841
Shares under derivative contract (in shares) | shares	1,800,000	24,000	1,800,000	24,000	16,000
Number of foreign exchange contracts | Contract	0	0	0	0	0
Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income/(loss) before income taxes	$ 125	$ 0	$ (18,964)	$ 50
Income tax provision	(45)	0	6,827	(18)
Net income/(loss)	80	0	(12,137)	32
Realized Gain on Sale of AFS Securities [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net gain/(loss) from investments	$ 125	$ 0	167	348
Other-than-Temporary Impairment of AFS Securities [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net gain/(loss) from investments			$ (19,131)	$ (298)

Investment in Securities, Fair

Investment in Securities, Fair Values and Gains and Losses of All Derivatives Held (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Derivatives, Fair Value [Line Items]
Asset derivatives fair values	$ 151	$ 178	$ 151	$ 178	$ 127
Liability derivatives fair value	501	33	501	33	37
Derivative Instruments, Gain (Loss) [Line Items]
Net gain (loss) on derivative	(456)	159	(490)	1,577
Net Gain/(loss) from Investments [Member] | Equity Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Net gain (loss) on derivative	(456)	159	(490)	204
Net Gain/(loss) from Investments [Member] | Foreign Exchange Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Net gain (loss) on derivative	0	0	0	1,373
Derivatives Designated as Hedging Instruments under FASB ASC 815-20 [Member]
Derivatives, Fair Value [Line Items]
Asset derivatives fair values	0	0	0	0	0
Liability derivatives fair value	0	0	0	0	0
Derivatives Designated as Hedging Instruments under FASB ASC 815-20 [Member] | Receivable from Brokers [Member] | Foreign Exchange Contracts [Member]
Derivatives, Fair Value [Line Items]
Asset derivatives fair values	0	0	0	0	0
Derivatives Designated as Hedging Instruments under FASB ASC 815-20 [Member] | Payable to Brokers [Member] | Foreign Exchange Contracts [Member]
Derivatives, Fair Value [Line Items]
Liability derivatives fair value	0	0	0	0	0
Derivatives Not Designated as Hedging Instruments under FASB ASC 815-20 [Member]
Derivatives, Fair Value [Line Items]
Asset derivatives fair values	151	178	151	178	127
Liability derivatives fair value	501	33	501	33	37
Derivatives Not Designated as Hedging Instruments under FASB ASC 815-20 [Member] | Receivable from Brokers [Member] | Foreign Exchange Contracts [Member]
Derivatives, Fair Value [Line Items]
Asset derivatives fair values	0	0	0	0	0
Derivatives Not Designated as Hedging Instruments under FASB ASC 815-20 [Member] | Payable to Brokers [Member] | Foreign Exchange Contracts [Member]
Derivatives, Fair Value [Line Items]
Liability derivatives fair value	0	0	0	0	0
Derivatives Not Designated as Hedging Instruments under FASB ASC 815-20 [Member] | Investments in Securities [Member] | Equity Contracts [Member]
Derivatives, Fair Value [Line Items]
Asset derivatives fair values	151	178	151	178	127
Derivatives Not Designated as Hedging Instruments under FASB ASC 815-20 [Member] | Securities Sold, Not yet Purchased [Member] | Equity Contracts [Member]
Derivatives, Fair Value [Line Items]
Liability derivatives fair value	$ 501	$ 33	$ 501	$ 33	$ 37

Investment in Securities, Maste

Investment in Securities, Master Netting Arrangements for Swaps (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016	Sep. 30, 2016
Offsetting derivative assets [Abstract]
Gross amounts of recognized assets	$ 151	$ 127	$ 178
Swaps [Member]
Offsetting derivative assets [Abstract]
Gross amounts of recognized assets	151	96	178
Gross amounts offset in the statements of financial condition	0	0	0
Net amounts of assets presented in the statements of financial condition	151	96	178
Gross amounts not offset in the statements of financial position, assets [Abstract]
Financial instruments	(151)	(9)	(14)
Cash collateral received	0	0	0
Net amount	0	87	164
Offsetting derivative liabilities [Abstract]
Gross amounts of recognized liabilities	500	9	14
Gross amounts offset in the statements of financial condition	0	0	0
Net amounts of liabilities presented in the statements of financial condition	500	9	14
Gross amounts not offset in the statements of financial position, liabilities [Abstract]
Financial instruments	(151)	(9)	(14)
Cash collateral pledged	0	0	0
Net amount	$ 349	$ 0	$ 0

Investment in Securities, Summa

Investment in Securities, Summary of Cost, Gross Unrealized Gains, Gross Unrealized Losses and Fair Value (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Available-for-sale Securities, fair value to amortized cost basis [Abstract]
Cost	$ 200,536,000	$ 215,989,000	$ 200,536,000	$ 215,989,000	$ 217,492,000
Gross unrealized gains	27,491,000	15,925,000	27,491,000	15,925,000	19,302,000
Gross unrealized losses	(331,000)	(24,940,000)	(331,000)	(24,940,000)	(14,299,000)
Fair value	227,696,000	206,974,000	227,696,000	206,974,000	222,495,000
Unrealized changes to fair value net of taxes included in other comprehensive income	1,700,000	(9,300,000)	14,200,000	(4,800,000)
Return of capital on available for sale securities	500,000	200,000	1,337,000	754,000
Proceeds from sale of investment available for sale	200,000	0	271,000	803,000
Gross gains on sale of investments available for sale reclassified from other comprehensive income	100,000	0	200,000	300,000
Gross losses on sale of investments available for sale	0	0	0	0
Common Stock [Member]
Available-for-sale Securities, fair value to amortized cost basis [Abstract]
Cost	130,869,000	150,000,000	130,869,000	150,000,000	150,000,000
Gross unrealized gains	0	0	0	0	0
Gross unrealized losses	(132,000)	(24,930,000)	(132,000)	(24,930,000)	(14,299,000)
Fair value	130,737,000	125,070,000	130,737,000	125,070,000	135,701,000
Closed-end Funds [Member]
Available-for-sale Securities, fair value to amortized cost basis [Abstract]
Cost	65,180,000	61,375,000	65,180,000	61,375,000	62,890,000
Gross unrealized gains	25,535,000	14,027,000	25,535,000	14,027,000	17,760,000
Gross unrealized losses	(199,000)	(10,000)	(199,000)	(10,000)	0
Fair value	90,516,000	75,392,000	90,516,000	75,392,000	80,650,000
Mutual Funds [Member]
Available-for-sale Securities, fair value to amortized cost basis [Abstract]
Cost	4,487,000	4,614,000	4,487,000	4,614,000	4,602,000
Gross unrealized gains	1,956,000	1,898,000	1,956,000	1,898,000	1,542,000
Gross unrealized losses	0	0	0	0	0
Fair value	$ 6,443,000	$ 6,512,000	$ 6,443,000	$ 6,512,000	$ 6,144,000

Investment in Securities, Inv38

Investment in Securities, Investments Classified as Available for Sale in Unrealized Loss Position (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2017USD ($)Investment	Sep. 30, 2016USD ($)Investment	Sep. 30, 2017USD ($)Investment	Sep. 30, 2016USD ($)Investment	Dec. 31, 2016USD ($)Investment
Investments classified as available for sale unrealized loss position [Abstract]
Cost	$ 132,733,000	$ 153,162,000	$ 132,733,000	$ 153,162,000	$ 150,000,000
Unrealized losses	(331,000)	(24,940,000)	(331,000)	(24,940,000)	(14,299,000)
Fair value	132,402,000	128,222,000	132,402,000	128,222,000	$ 135,701,000
Losses deemed to be other than temporary	$ 0	$ 0	$ 19,100,000	$ 300,000
Number of investment holdings in loss positions | Investment	2	2	2	2	1
Common Stocks [Member]
Investments classified as available for sale unrealized loss position [Abstract]
Cost	$ 130,869,000	$ 150,000,000	$ 130,869,000	$ 150,000,000	$ 150,000,000
Unrealized losses	(132,000)	(24,930,000)	(132,000)	(24,930,000)	(14,299,000)
Fair value	130,737,000	125,070,000	$ 130,737,000	125,070,000	135,701,000
Common Stocks [Member] | Investment Holding Group One [Member]
Investments classified as available for sale unrealized loss position [Abstract]
Investment holding impairment period			7 months
Common Stocks [Member] | Investment Holding Group Two [Member]
Investments classified as available for sale unrealized loss position [Abstract]
Investment holding impairment period			4 months
Closed-end Funds [Member]
Investments classified as available for sale unrealized loss position [Abstract]
Cost	1,864,000	3,162,000	$ 1,864,000	3,162,000	0
Unrealized losses	(199,000)	(10,000)	(199,000)	(10,000)	0
Fair value	$ 1,665,000	$ 3,152,000	$ 1,665,000	$ 3,152,000	$ 0
Closed-end Funds [Member] | Investment Holding Group One [Member]
Investments classified as available for sale unrealized loss position [Abstract]
Number of investment holdings in loss positions | Investment	1	1	1	1
Investment holding impairment period			1 month

Fair Value, Assets and Liabilit

Fair Value, Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands		Sep. 30, 2017	Dec. 31, 2016	Sep. 30, 2016
Assets [Abstract]
Investments in partnerships		$ 8,297	$ 8,343	$ 8,123
Investments in securities (including GBL stock) [Abstract]
Total investments in securities		424,609	342,797	231,542
Liabilities [Abstract]
Securities sold, not yet purchased		9,059	9,984	4,215
Recurring Basis [Member]
Assets [Abstract]
Cash equivalents		240,727	314,082	402,391
Investments in partnerships		141,094	129,398	128,198
Investments in securities (including GBL stock) [Abstract]
AFS - Common stocks		130,737	135,701	125,070
AFS - Mutual funds		284	500	481
Trading - Gov't obligations		116,152	119,823	24,995
Trading - Common stocks		172,312	82,158	77,031
Trading - Mutual funds		3,633	3,143	3,031
Trading - Other		1,491	1,472	934
Total investments in securities		424,609	342,797	231,542
Investments in affiliated registered investment companies [Abstract]
AFS - Closed-end funds		90,516	80,650	75,392
AFS - Mutual funds		6,159	5,644	6,031
Trading - Mutual funds		46,390	45,351	44,799
Total investments in affiliated registered investment companies		143,065	131,645	126,222
Total investments		708,768	603,840	485,962
Total assets at fair value		949,495	917,922	888,353
Liabilities [Abstract]
Trading - Common stocks		8,558	9,947	3,948
Trading - Other		501	37	267
Securities sold, not yet purchased		9,059	9,984	4,215
Recurring Basis [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Assets [Abstract]
Cash equivalents		240,727	314,082	402,391
Investments in partnerships		0	0	0
Investments in securities (including GBL stock) [Abstract]
AFS - Common stocks		130,737	135,701	125,070
AFS - Mutual funds		284	500	481
Trading - Gov't obligations		116,152	119,823	24,995
Trading - Common stocks		171,835	81,696	76,570
Trading - Mutual funds		3,633	3,143	3,031
Trading - Other		994	1,062	476
Total investments in securities		423,635	341,925	230,623
Investments in affiliated registered investment companies [Abstract]
AFS - Closed-end funds		90,516	80,650	72,240
AFS - Mutual funds		6,159	5,644	6,031
Trading - Mutual funds		46,390	45,351	44,799
Total investments in affiliated registered investment companies		143,065	131,645	123,070
Total investments		566,700	473,570	353,693
Total assets at fair value		807,427	787,652	756,084
Liabilities [Abstract]
Trading - Common stocks		8,558	9,947	3,948
Trading - Other		0	0	0
Securities sold, not yet purchased		8,558	9,947	3,948
Recurring Basis [Member] | Significant Other Observable Inputs (Level 2) [Member]
Assets [Abstract]
Cash equivalents		0	0	0
Investments in partnerships		0	0	0
Investments in securities (including GBL stock) [Abstract]
AFS - Common stocks		0	0	0
AFS - Mutual funds		0	0	0
Trading - Gov't obligations		0	0	0
Trading - Common stocks		1	1	0
Trading - Mutual funds		0	0	0
Trading - Other		151	127	178
Total investments in securities		152	128	178
Investments in affiliated registered investment companies [Abstract]
AFS - Closed-end funds		0	0	3,152
AFS - Mutual funds		0	0	0
Trading - Mutual funds		0	0	0
Total investments in affiliated registered investment companies		0	0	3,152
Total investments		152	128	3,330
Total assets at fair value		152	128	3,330
Liabilities [Abstract]
Trading - Common stocks		0	0	0
Trading - Other		501	37	267
Securities sold, not yet purchased		501	37	267
Recurring Basis [Member] | Significant Unobservable Inputs (Level 3) [Member]
Assets [Abstract]
Cash equivalents		0	0	0
Investments in partnerships		0	0	0
Investments in securities (including GBL stock) [Abstract]
AFS - Common stocks		0	0	0
AFS - Mutual funds		0	0	0
Trading - Gov't obligations		0	0	0
Trading - Common stocks		476	461	461
Trading - Mutual funds		0	0	0
Trading - Other		346	283	280
Total investments in securities		822	744	741
Investments in affiliated registered investment companies [Abstract]
AFS - Closed-end funds		0	0	0
AFS - Mutual funds		0	0	0
Trading - Mutual funds		0	0	0
Total investments in affiliated registered investment companies		0	0	0
Total investments		822	744	741
Total assets at fair value		822	744	741
Liabilities [Abstract]
Trading - Common stocks		0	0	0
Trading - Other		0	0	0
Securities sold, not yet purchased		0	0	0
Recurring Basis [Member] | Investments Measured at NAV [Member]
Assets [Abstract]
Cash equivalents	[1]	0	0	0
Investments in partnerships	[1]	138,035	125,527	125,977
Investments in securities (including GBL stock) [Abstract]
AFS - Common stocks	[1]	0	0	0
AFS - Mutual funds	[1]	0	0	0
Trading - Gov't obligations	[1]	0	0	0
Trading - Common stocks	[1]	0	0	0
Trading - Mutual funds	[1]	0	0	0
Trading - Other	[1]	0	0	0
Total investments in securities	[1]	0	0	0
Investments in affiliated registered investment companies [Abstract]
AFS - Closed-end funds	[1]	0	0	0
AFS - Mutual funds	[1]	0	0	0
Trading - Mutual funds	[1]	0	0	0
Total investments in affiliated registered investment companies	[1]	0	0	0
Total investments	[1]	138,035	125,527	125,977
Total assets at fair value	[1]	138,035	125,527	125,977
Liabilities [Abstract]
Trading - Common stocks	[1]	0	0	0
Trading - Other	[1]	0	0	0
Securities sold, not yet purchased	[1]	0	0	0
Recurring Basis [Member] | Other Assets Not Held at Fair Value [Member]
Assets [Abstract]
Cash equivalents	[2]	0	0	0
Investments in partnerships	[2]	3,059	3,871	2,221
Investments in securities (including GBL stock) [Abstract]
AFS - Common stocks	[2]	0	0	0
AFS - Mutual funds	[2]	0	0	0
Trading - Gov't obligations	[2]	0	0	0
Trading - Common stocks	[2]	0	0	0
Trading - Mutual funds	[2]	0	0	0
Trading - Other	[2]	0	0	0
Total investments in securities	[2]	0	0	0
Investments in affiliated registered investment companies [Abstract]
AFS - Closed-end funds	[2]	0	0	0
AFS - Mutual funds	[2]	0	0	0
Trading - Mutual funds	[2]	0	0	0
Total investments in affiliated registered investment companies	[2]	0	0	0
Total investments	[2]	3,059	3,871	2,221
Total assets at fair value	[2]	3,059	3,871	2,221
Liabilities [Abstract]
Trading - Common stocks	[2]	0	0	0
Trading - Other	[2]	0	0	0
Securities sold, not yet purchased	[2]	$ 0	$ 0	$ 0
[1]	Includes certain investments measured at fair value using NAV (or its equivalent) as a practical expedient. These investments have not been classified in the fair value hierarchy.
[2]	Includes certain equity method investments which are not accounted for under a fair value measure. In accordance with GAAP, certain equity method investees do not account for their financial assets and liabilities under fair value measures; therefore, the Company's investment in such equity method investees may not represent fair value.

Fair Value, Changes in Level 3

Fair Value, Changes in Level 3 Assets Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Changes in Level 3 Assets Measured at Fair Value on a Recurring Basis [Roll Forward]
Beginning balance	$ 959	$ 798	$ 744	$ 813
Total realized and unrealized gains or (losses) in income - trading	41	(37)	97	(52)
Total realized and unrealized gains or (losses) in income - AFS investments	0	0	0	0
Total unrealized gains or (losses) included in other comprehensive income	0	0	0	0
Total realized and unrealized gains or (losses)	41	(37)	97	(52)
Purchases	0	0	167	0
Sales	(142)	(20)	(150)	(20)
Transfers in and/or (out) of Level 3	(36)	0	(36)	0
Ending balance	822	741	822	741
Trading - Common Stocks [Member]
Changes in Level 3 Assets Measured at Fair Value on a Recurring Basis [Roll Forward]
Beginning balance	510	502	461	508
Total realized and unrealized gains or (losses) in income - trading	2	(41)	51	(47)
Total realized and unrealized gains or (losses) in income - AFS investments	0	0	0	0
Total unrealized gains or (losses) included in other comprehensive income	0	0	0	0
Total realized and unrealized gains or (losses)	2	(41)	51	(47)
Purchases	0	0	0	0
Sales	0	0	0	0
Transfers in and/or (out) of Level 3	(36)	0	(36)	0
Ending balance	476	461	476	461
Trading - Other [Member]
Changes in Level 3 Assets Measured at Fair Value on a Recurring Basis [Roll Forward]
Beginning balance	449	296	283	305
Total realized and unrealized gains or (losses) in income - trading	39	4	46	(5)
Total realized and unrealized gains or (losses) in income - AFS investments	0	0	0	0
Total unrealized gains or (losses) included in other comprehensive income	0	0	0	0
Total realized and unrealized gains or (losses)	39	4	46	(5)
Purchases	0	0	167	0
Sales	(142)	(20)	(150)	(20)
Transfers in and/or (out) of Level 3	0	0	0	0
Ending balance	$ 346	$ 280	$ 346	$ 280

Investments in Partnerships, 41

Investments in Partnerships, Offshore Funds and Variable Interest Entities ("VIEs"), Breakdown of Consolidated Entities and Investments in Partnerships Line by Accounting Method (Details) $ in Thousands	3 Months Ended	9 Months Ended
	Dec. 31, 2016USD ($)Entity	Sep. 30, 2017USD ($)Entity	Sep. 30, 2016USD ($)Entity
Variable Interest Entity [Line Items]
Investments in affiliated entities | $	$ 112,300	$ 122,600	$ 113,400
Investments in unaffiliated entities | $	17,100	$ 18,500	$ 14,800
Number of entities consolidated		3	2
Investments in Partnerships by Accounting Method [Abstract]
Fair value | $	8,343	$ 8,297	$ 8,123
Equity method | $	121,055	132,797	120,075
Total | $	$ 129,398	$ 141,094	$ 128,198
VIEs [Member]
Entities Consolidated [Roll Forward]
Entities consolidated at beginning of period	1	1	2
Additional consolidated entities	0	0	1
Deconsolidated entities	0	0	(2)
Entities consolidated at end of period	1	1	1
VOEs [Member]
Entities Consolidated [Roll Forward]
Entities consolidated at beginning of period	1	1	4
Additional consolidated entities	0	1	0
Deconsolidated entities	0	0	(3)
Entities consolidated at end of period	1	2	1
Prior to Consolidation [Member]
Investments in Partnerships by Accounting Method [Abstract]
Total | $	$ 133,794	$ 155,462	$ 132,564
CFFs [Member]
Investments in Partnerships by Accounting Method [Abstract]
Total | $	3,964	3,803	3,730
CFFs [Member] | Affiliated [Member]
Investments in Partnerships by Accounting Method [Abstract]
Fair value | $	8,343	8,297	8,123
Equity method | $	0	0	0
Total | $	$ 8,343	$ 8,297	$ 8,123
CFFs [Member] | VIEs [Member]
Entities Consolidated [Roll Forward]
Entities consolidated at beginning of period	0	0	1
Additional consolidated entities	0	0	0
Deconsolidated entities	0	0	(1)
Entities consolidated at end of period	0	0	0
CFFs [Member] | VOEs [Member]
Entities Consolidated [Roll Forward]
Entities consolidated at beginning of period	1	1	2
Additional consolidated entities	0	0	0
Deconsolidated entities	0	0	(1)
Entities consolidated at end of period	1	1	1
Partnerships [Member]
Investments in Partnerships by Accounting Method [Abstract]
Total | $	$ (8,360)	$ (8,936)	$ (8,096)
Partnerships [Member] | Affiliated [Member]
Investments in Partnerships by Accounting Method [Abstract]
Fair value | $	0	0	0
Equity method | $	33,202	41,169	40,516
Total | $	33,202	41,169	40,516
Partnerships [Member] | Unaffiliated [Member]
Investments in Partnerships by Accounting Method [Abstract]
Fair value | $	0	0	0
Equity method | $	6,761	6,104	5,438
Total | $	$ 6,761	$ 6,104	$ 5,438
Partnerships [Member] | VIEs [Member]
Entities Consolidated [Roll Forward]
Entities consolidated at beginning of period	1	1	0
Additional consolidated entities	0	0	1
Deconsolidated entities	0	0	0
Entities consolidated at end of period	1	1	1
Partnerships [Member] | VOEs [Member]
Entities Consolidated [Roll Forward]
Entities consolidated at beginning of period	0	0	2
Additional consolidated entities	0	0	0
Deconsolidated entities	0	0	(2)
Entities consolidated at end of period	0	0	0
Offshore Funds [Member]
Investments in Partnerships by Accounting Method [Abstract]
Total | $	$ 0	$ (9,235)	$ 0
Offshore Funds [Member] | Affiliated [Member]
Investments in Partnerships by Accounting Method [Abstract]
Fair value | $	0	0	0
Equity method | $	70,745	73,146	64,810
Total | $	70,745	73,146	64,810
Offshore Funds [Member] | Unaffiliated [Member]
Investments in Partnerships by Accounting Method [Abstract]
Fair value | $	0	0	0
Equity method | $	10,347	12,378	9,311
Total | $	$ 10,347	$ 12,378	$ 9,311
Offshore Funds [Member] | VIEs [Member]
Entities Consolidated [Roll Forward]
Entities consolidated at beginning of period	0	0	1
Additional consolidated entities	0	0	0
Deconsolidated entities	0	0	(1)
Entities consolidated at end of period	0	0	0
Offshore Funds [Member] | VOEs [Member]
Entities Consolidated [Roll Forward]
Entities consolidated at beginning of period	0	0	0
Additional consolidated entities	0	1	0
Deconsolidated entities	0	0	0
Entities consolidated at end of period	0	1	0

Investments in Partnerships, 42

Investments in Partnerships, Offshore Funds and Variable Interest Entities ("VIEs"), Net Impact by Line Item on the Condensed Consolidated Statements of Financial Position (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016	Dec. 31, 2015
Assets [Abstract]
Cash and cash equivalents	$ 242,302	$ 402,403	$ 242,302	$ 402,403	$ 314,093	$ 205,750
Investments in securities (including GBL stock)	424,609	231,542	424,609	231,542	342,797
Investments in affiliated registered investment companies	143,065	126,222	143,065	126,222	131,645
Investments in partnerships	141,094	128,198	141,094	128,198	129,398
Receivable from brokers	15,753	19,807	15,753	19,807	12,588
Investment advisory fees receivable	1,433	1,932	1,433	1,932	9,784
Other assets	11,263	14,707	11,263	14,707	12,298
Total assets	979,519	924,811	979,519	924,811	952,603
Liabilities and equity [Abstract]
Securities sold, not yet purchased	9,059	4,215	9,059	4,215	9,984
Accrued expenses and other liabilities	30,133	18,528	30,133	18,528	64,367
Redeemable noncontrolling interests	42,119	3,999	42,119	3,999	4,230
Total equity	898,208	898,069	898,208	898,069	874,022	$ 751,549
Total liabilities and equity	979,519	924,811	979,519	924,811	952,603
Consolidated Statements of Income [Abstract]
Total revenues	5,248	5,451	15,330	14,932
Total expenses	11,360	9,948	32,227	27,296
Operating loss	(6,112)	(4,497)	(16,897)	(12,364)
Total other income/(expense), net	7,512	10,333	1,172	21,978
Income/(loss) before income taxes	1,400	5,836	(15,725)	9,614
Income tax provision	67	1,807	(8,667)	2,773
Net income/(loss)	1,333	4,029	(7,058)	6,841
Net income (loss) attributable to noncontrolling interests	(186)	70	(95)	270
Net income/(loss) attributable to Associated Capital Group, Inc.'s shareholders	1,519	3,959	(6,963)	6,571
Prior to Consolidation [Member]
Assets [Abstract]
Cash and cash equivalents	234,124	402,395	234,124	402,395	313,785
Investments in securities (including GBL stock)	320,021	224,996	320,021	224,996	336,459
Investments in affiliated registered investment companies	195,401	126,222	195,401	126,222	131,645
Investments in partnerships	155,462	132,564	155,462	132,564	133,794
Receivable from brokers	8,208	17,943	8,208	17,943	10,542
Investment advisory fees receivable	1,445	1,944	1,445	1,944	9,800
Other assets	11,163	14,707	11,163	14,707	12,298
Total assets	925,824	920,771	925,824	920,771	948,323
Liabilities and equity [Abstract]
Securities sold, not yet purchased	8,585	4,215	8,585	4,215	9,984
Accrued expenses and other liabilities	19,031	18,487	19,031	18,487	64,317
Redeemable noncontrolling interests	0	0	0	0	0
Total equity	898,208	898,069	898,208	898,069	874,022
Total liabilities and equity	925,824	920,771	925,824	920,771	948,323
Consolidated Statements of Income [Abstract]
Total revenues	5,252	5,456	15,345	14,946
Total expenses	10,188	9,910	30,959	27,170
Operating loss	(4,936)	(4,454)	(15,614)	(12,224)
Total other income/(expense), net	6,522	10,220	(16)	21,522
Income/(loss) before income taxes	1,586	5,766	(15,630)	9,298
Income tax provision	67	1,807	(8,667)	2,773
Net income/(loss)	1,519	3,959	(6,963)	6,525
Net income (loss) attributable to noncontrolling interests	0	0	0	(46)
Net income/(loss) attributable to Associated Capital Group, Inc.'s shareholders	1,519	3,959	(6,963)	6,571
CFFs [Member]
Assets [Abstract]
Cash and cash equivalents	0	0	0	0	0
Investments in securities (including GBL stock)	0	0	0	0	0
Investments in affiliated registered investment companies	0	0	0	0	0
Investments in partnerships	3,803	3,730	3,803	3,730	3,964
Receivable from brokers	0	0	0	0	0
Investment advisory fees receivable	(4)	(7)	(4)	(7)	(8)
Other assets	0	0	0	0	0
Total assets	3,799	3,723	3,799	3,723	3,956
Liabilities and equity [Abstract]
Securities sold, not yet purchased	0	0	0	0	0
Accrued expenses and other liabilities	15	11	15	11	13
Redeemable noncontrolling interests	3,784	3,712	3,784	3,712	3,943
Total equity	0	0	0	0	0
Total liabilities and equity	3,799	3,723	3,799	3,723	3,956
Consolidated Statements of Income [Abstract]
Total revenues	(4)	(4)	(13)	(12)
Total expenses	28	29	103	91
Operating loss	(32)	(33)	(116)	(103)
Total other income/(expense), net	32	110	191	414
Income/(loss) before income taxes	0	77	75	311
Income tax provision	0	0	0	0
Net income/(loss)	0	77	75	311
Net income (loss) attributable to noncontrolling interests	0	77	75	311
Net income/(loss) attributable to Associated Capital Group, Inc.'s shareholders	0	0	0	0
Partnerships [Member]
Assets [Abstract]
Cash and cash equivalents	119	8	119	8	308
Investments in securities (including GBL stock)	6,948	6,546	6,948	6,546	6,338
Investments in affiliated registered investment companies	0	0	0	0	0
Investments in partnerships	(8,936)	(8,096)	(8,936)	(8,096)	(8,360)
Receivable from brokers	2,217	1,864	2,217	1,864	2,046
Investment advisory fees receivable	(8)	(5)	(8)	(5)	(8)
Other assets	0	0	0	0	0
Total assets	340	317	340	317	324
Liabilities and equity [Abstract]
Securities sold, not yet purchased	0	0	0	0	0
Accrued expenses and other liabilities	28	30	28	30	37
Redeemable noncontrolling interests	312	287	312	287	287
Total equity	0	0	0	0	0
Total liabilities and equity	340	317	340	317	324
Consolidated Statements of Income [Abstract]
Total revenues	0	(1)	(2)	(2)
Total expenses	11	9	32	35
Operating loss	(11)	(10)	(34)	(37)
Total other income/(expense), net	22	3	61	42
Income/(loss) before income taxes	11	(7)	27	5
Income tax provision	0	0	0	0
Net income/(loss)	11	(7)	27	5
Net income (loss) attributable to noncontrolling interests	11	(7)	27	5
Net income/(loss) attributable to Associated Capital Group, Inc.'s shareholders	0	0	0	0
Offshore Funds [Member]
Assets [Abstract]
Cash and cash equivalents	8,059	0	8,059	0	0
Investments in securities (including GBL stock)	97,640	0	97,640	0	0
Investments in affiliated registered investment companies	(52,336)	0	(52,336)	0	0
Investments in partnerships	(9,235)	0	(9,235)	0	0
Receivable from brokers	5,328	0	5,328	0	0
Investment advisory fees receivable	0	0	0	0	0
Other assets	100	0	100	0	0
Total assets	49,556	0	49,556	0	0
Liabilities and equity [Abstract]
Securities sold, not yet purchased	474	0	474	0	0
Accrued expenses and other liabilities	11,059	0	11,059	0	0
Redeemable noncontrolling interests	38,023	0	38,023	0	0
Total equity	0	0	0	0	0
Total liabilities and equity	49,556	0	49,556	0	$ 0
Consolidated Statements of Income [Abstract]
Total revenues	0	0	0	0
Total expenses	1,133	0	1,133	0
Operating loss	(1,133)	0	(1,133)	0
Total other income/(expense), net	936	0	936	0
Income/(loss) before income taxes	(197)	0	(197)	0
Income tax provision	0	0	0	0
Net income/(loss)	(197)	0	(197)	0
Net income (loss) attributable to noncontrolling interests	(197)	0	(197)	0
Net income/(loss) attributable to Associated Capital Group, Inc.'s shareholders	$ 0	$ 0	$ 0	$ 0

Investments in Partnerships, 43

Investments in Partnerships, Offshore Funds and Variable Interest Entities ("VIEs"), Variable Interest Entities (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016	Sep. 30, 2016	Dec. 31, 2015
Balances related to VIEs [Abstract]
Cash and cash equivalents	$ 242,302	$ 314,093	$ 402,403	$ 205,750
Investments in securities	424,609	342,797	231,542
Investments in partnerships	141,094	129,398	128,198
Receivable from broker	15,753	12,588	19,807
Other assets	4,667	7,353	3,368
Payable to brokers	(13,421)	(2,396)	(1,549)
Securities sold, not yet purchased	(9,059)	(9,984)	(4,215)
Accrued expenses and other liabilities	(30,133)	(64,367)	(18,528)
Redeemable noncontrolling interests	(42,119)	(4,230)	(3,999)
VIEs [Member]
Balances related to VIEs [Abstract]
Cash and cash equivalents	119	308	8
Investments in securities	6,948	6,338	6,546
Receivable from broker	2,217	2,046	1,864
Other assets	(8)	(8)	(5)
Accrued expenses and other liabilities	(28)	(37)	(29)
Redeemable noncontrolling interests	(312)	(287)	(288)
AC Group's net interests in consolidated VIE	$ 8,936	$ 8,360	$ 8,096

Income Taxes (Details)

Income Taxes (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Income Taxes [Abstract]
Effective income tax rate	4.80%	31.00%	55.10%	28.80%
Standard corporate tax rate			34.00%	34.00%

Earnings Per Share (Details)

Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Basic [Abstract]
Net income/(loss) attributable to Associated Capital Group, Inc.'s shareholders	$ 1,519	$ 3,959	$ (6,963)	$ 6,571
Weighted average shares outstanding (in shares)	23,841	24,918	23,826	24,879
Basic net income/(loss) attributable to Associated Capital Group, Inc.'s shareholders per share (in dollars per share)	$ 0.06	$ 0.16	$ (0.29)	$ 0.26
Diluted [Abstract]
Net income/(loss) attributable to Associated Capital Group, Inc.'s shareholders	$ 1,519	$ 3,959	$ (6,963)	$ 6,571
Weighted average shares outstanding (in shares)	23,841	24,918	23,826	24,879
Dilutive restricted stock awards (in shares)	0	301	0	315
Total (in shares)	23,841	25,219	23,826	25,194
Diluted net income/(loss) attributable to Associated Capital Group, Inc.'s shareholders per share (in dollars per share)	$ 0.06	$ 0.16	$ (0.29)	$ 0.26

Stockholders' Equity (Details)

Stockholders' Equity (Details) $ / shares in Units, $ in Thousands	Aug. 07, 2017shares	Jun. 01, 2017shares	Nov. 30, 2015shares	Sep. 30, 2017USD ($)$ / sharesshares	Jun. 30, 2017USD ($)	Mar. 31, 2017USD ($)	Dec. 31, 2016USD ($)shares	Sep. 30, 2016USD ($)$ / sharesshares	Jun. 30, 2016USD ($)	Mar. 31, 2016USD ($)	Sep. 30, 2017USD ($)VoteperSharePlan$ / sharesshares	Sep. 30, 2016USD ($)$ / sharesshares	Dec. 31, 2016USD ($)shares
Stockholders' Equity [Abstract]
Shares outstanding (in shares) | shares				23,800,000			24,300,000	25,400,000			23,800,000	25,400,000	24,300,000
Dividends [Abstract]
Dividends declared (in dollars per share) | $ / shares				$ 0				$ 0			$ 0.10	$ 0.10
Stock Award and Incentive Plan [Abstract]
Number of incentive plans | Plan											1
Number of AC shares issued for each GAMCO shares in connection with spin-off (in shares) | shares			1
Actual and projected stock based compensation expense for RSA shares and options [Abstract]
Actual stock based compensation expense				$ 1,862	$ 2,920	$ 444	$ 449	$ 727	$ 644	$ 644	$ 5,226	$ 2,015	$ 2,464
2,017				5,309							5,309
2,018				246							246
2,019				211							211
2,020				81							81
2,021				52							52
2,022				32							32
2,023				14							14
2,024				3							3
Employee Service Share-based Compensation, Aggregate Disclosures [Abstract]
Compensation cost related to non-vested options not yet recognized				$ 700							700
GAMCO [Member]
Stock Award and Incentive Plan [Abstract]
Number of GAMCO shares exchanged for each AC shares in connection with spin-off (in shares) | shares			1
Restricted Stock Awards [Member]
Stock Award and Incentive Plan [Abstract]
RSAs granted (in shares) | shares			554,100
RSA shares outstanding (in shares) | shares							424,340	427,290				427,290	424,340
Number of shares with accelerated vesting (in shares) | shares		420,240
Incremental stock-based compensation expenses due to accelerated vesting											$ 2,500
Restricted Stock Awards [Member] | Vesting Option One [Member]
Stock Award and Incentive Plan [Abstract]
Award vesting period											5 years
Restricted Stock Awards [Member] | Vesting in Three Years from Date of Grant [Member]
Stock Award and Incentive Plan [Abstract]
Award vesting percentage											30.00%
Award vesting period											3 years
Restricted Stock Awards [Member] | Vesting in Five Years from Date of Grant [Member]
Stock Award and Incentive Plan [Abstract]
Award vesting percentage											70.00%
Award vesting period											5 years
Restricted Stock Awards [Member] | Vesting Option Two [Member]
Stock Award and Incentive Plan [Abstract]
Award vesting period											10 years
Restricted Stock Awards [Member] | Vesting in Year Four from Date of Grant [Member]
Stock Award and Incentive Plan [Abstract]
Award vesting percentage											10.00%
Restricted Stock Awards [Member] | Vesting in Year Five from Date of Grant [Member]
Stock Award and Incentive Plan [Abstract]
Award vesting percentage											10.00%
Restricted Stock Awards [Member] | Vesting in Year Six from Date of Grant [Member]
Stock Award and Incentive Plan [Abstract]
Award vesting percentage											10.00%
Restricted Stock Awards [Member] | Vesting in Year Seven from Date of Grant [Member]
Stock Award and Incentive Plan [Abstract]
Award vesting percentage											10.00%
Restricted Stock Awards [Member] | Vesting in Year Eight from Date of Grant [Member]
Stock Award and Incentive Plan [Abstract]
Award vesting percentage											10.00%
Restricted Stock Awards [Member] | Vesting in Year Nine from Date of Grant [Member]
Stock Award and Incentive Plan [Abstract]
Award vesting percentage											10.00%
Restricted Stock Awards [Member] | Vesting in Year Ten from Date of Grant [Member]
Stock Award and Incentive Plan [Abstract]
Award vesting percentage											10.00%
Restricted Stock Awards [Member] | GAMCO [Member]
Stock Award and Incentive Plan [Abstract]
Number of GAMCO shares exchanged in connection with spin-off (in shares) | shares			554,100
RSA shares outstanding (in shares) | shares				164,050							164,050
Number of shares with accelerated vesting (in shares) | shares	201,120
Incremental stock-based compensation expenses due to accelerated vesting				$ 1,600							$ 1,600
Q1 [Member]
Actual and projected stock based compensation expense for RSA shares and options [Abstract]
2,018				67							67
2,019				56							56
2,020				26							26
2,021				15							15
2,022				10							10
2,023				5							5
2,024				1							1
Q2 [Member]
Actual and projected stock based compensation expense for RSA shares and options [Abstract]
2,018				64							64
2,019				56							56
2,020				22							22
2,021				15							15
2,022				10							10
2,023				5							5
2,024				1							1
Q3 [Member]
Actual and projected stock based compensation expense for RSA shares and options [Abstract]
2,017				1,862							1,862
2,018				59							59
2,019				51							51
2,020				18							18
2,021				12							12
2,022				7							7
2,023				3							3
2,024				1							1
Q4 [Member]
Actual and projected stock based compensation expense for RSA shares and options [Abstract]
2,017				83							83
2,018				56							56
2,019				48							48
2,020				15							15
2,021				10							10
2,022				5							5
2,023				1							1
2,024				$ 0							$ 0
Class A [Member]
Stockholders' Equity [Abstract]
Shares outstanding (in shares) | shares				4,590,578			5,058,648	6,164,275			4,590,578	6,164,275	5,058,648
Voting Rights [Abstract]
Number of votes per share | VoteperShare											1
Class A [Member] | Maximum [Member]
Stock Award and Incentive Plan [Abstract]
Number of shares reserved for issuance under each plan (in shares) | shares				2,000,000							2,000,000
Class B [Member]
Stockholders' Equity [Abstract]
Shares outstanding (in shares) | shares				19,195,649			19,196,792	19,196,792			19,195,649	19,196,792	19,196,792
Voting Rights [Abstract]
Number of votes per share | VoteperShare											10

Goodwill and Identifiable Int47

Goodwill and Identifiable Intangible Assets (Details) - USD ($) $ in Thousands	3 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Goodwill [Line Items]
Goodwill	$ 3,422	$ 3,422	$ 3,422
Impairment charges on goodwill	0	$ 0
GCIA [Member]
Goodwill [Line Items]
Goodwill	$ 3,400

Shareholder-Designated Contri48

Shareholder-Designated Contribution Plan (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Shareholder-Designated Contribution Plan [Abstract]
Contribution price (in dollars per share)					$ 0.25
Shareholder-designated contribution	$ 0	$ 0	$ (4,895)	$ 0

Contractual Obligations (Detail

Contractual Obligations (Details) $ in Thousands	Sep. 30, 2017USD ($)
Future minimum lease commitment under operating lease [Abstract]
2,017	$ 94
2,018	94
Total	$ 188

Subsequent Events (Details)

Subsequent Events (Details) - USD ($) $ / shares in Units, $ in Millions	Nov. 07, 2017	Oct. 03, 2017	Nov. 07, 2017	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Mar. 31, 2017
Subsequent Event [Line Items]
Dividends declared (in dollars per share)				$ 0	$ 0	$ 0.10	$ 0.10
GAMCO Note [Member]
Subsequent Event [Line Items]
Prepayment of note				$ 10				$ 180
Principal amount outstanding				$ 70		$ 70
Subsequent Event [Member]
Subsequent Event [Line Items]
Dividends declared (in dollars per share)	$ 0.10
Dividends payable date	Jan. 10, 2018
Dividends record date	Dec. 27, 2017
Subsequent Event [Member] | GAMCO Note [Member]
Subsequent Event [Line Items]
Prepayment of note		$ 20
Principal amount outstanding		$ 50
Subsequent Event [Member] | Repurchase of Common Stock [Member]
Subsequent Event [Line Items]
Number of shares of stock repurchased (in shares)			95,775
Average price per share of repurchased shares (in dollars per share)			$ 0