Fortress Biotech (FBIO) 10-Q9 Nov 172017 Q3 Quarterly reportFinancial data

Company Profile

Document And Entity Information

Document And Entity Information - shares	9 Months Ended
Document And Entity Information - shares	Sep. 30, 2017	Nov. 09, 2017
Document Information [Line Items]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2017
Document Fiscal Year Focus	2,017
Document Fiscal Period Focus	Q3
Entity Registrant Name	Fortress Biotech, Inc.
Entity Central Index Key	1,429,260
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Trading Symbol	FBIO
Entity Common Stock, Shares Outstanding		50,656,503

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Current assets
Cash and cash equivalents	$ 110,536	$ 88,294
Accounts receivable	5,582	1,830
Short-term investment (certificate of deposit)	44,088	0
Cash deposits with clearing organizations	1,040	1,030
Receivables from broker-dealers and clearing organizations	8,282	3,357
Forgivable loans receivable	1,269	1,712
Securities owned, at fair value	1,595	2,357
Inventory	318	203
Other receivables - related party	638	1,790
Prepaid expenses and other current assets	10,739	9,061
Total current assets	184,087	109,634
Property and equipment, net	8,221	7,376
Restricted cash	16,886	15,860
Long-term investments, at fair value	923	1,414
Intangible asset	15,983	17,408
Goodwill	18,645	18,645
Other assets	346	394
Total assets	245,091	170,731
Current liabilities
Accounts payable and accrued expenses	31,978	23,871
Accrued expense - related party	88	0
Accrued commissions and payroll payable	11,255	11,940
Deferred clearing and marketing credits	838	995
Deferred product revenue	680	0
Securities sold, not yet purchased, at fair value	0	298
Interest payable	161	88
Interest payable - related party	497	77
Notes payable, short-term (net of debt discount of $1,277 and $0 at September 30, 2017 and December 31, 2016, respectively)	8,223	1,000
Subsidiary convertible note, short-term, at fair value	4,733	1,031
Contingent consideration payable	637	424
Warrants issued in 2017 and issuable in 2016 - National	8,832	14,359
Contingently issuable liabilities	0	1,682
Derivative warrant liability	313	481
Other current liabilities	193	319
Total current liabilities	68,428	56,565
Notes payable, long-term (net of debt discount of $2,550 and $2,009 at September 30, 2017 and December 31, 2016, respectively)	40,734	22,528
Subsidiary convertible note, long-term, at fair value	9,928	3,656
Other long-term liabilities	4,736	5,014
Total liabilities	123,826	87,763
Commitments and contingencies
Stockholders' equity
Common stock, $.001 par value, 100,000,000 shares authorized, 50,584,937 and 48,932,023 shares issued and outstanding as of September 30, 2017 and December 31, 2016, respectively	51	49
Common stock issuable, 86,272 and 0 shares as of September 30, 2017 and December 31, 2016, respectively	353	0
Additional paid-in-capital	338,254	283,697
Accumulated deficit	(301,714)	(245,251)
Total stockholders' equity attributed to the Company	36,944	38,495
Non-controlling interests	84,321	44,473
Total stockholders' equity	121,265	82,968
Total liabilities and stockholders' equity	245,091	170,731
Series C Convertible Preferred Stock [Member]
Stockholders' equity
Convertible preferred stock, $.001 par value, 129,767 Series C shares authorized, 0 shares issued and outstanding as of September 30, 2017 and December 31, 2016, respectively	$ 0	$ 0

Condensed Consolidated Balance3

Condensed Consolidated Balance Sheets (Parenthetical) - USD ($)	Sep. 30, 2017	Dec. 31, 2016
Common Stock, par value	$ 0.001	$ 0.001
Common Stock, shares authorized	100,000,000	100,000,000
Common Stock, shares issued	50,584,937	48,932,023
Common Stock, shares outstanding	50,584,937	48,932,023
Common Stock, Shares Subscribed but Unissued	86,272	0
Debt Instrument, Unamortized Discount, Current	$ 1,277	$ 0
Debt Instrument, Unamortized Discount, Noncurrent	$ 2,550	$ 2,009
Series C Convertible Preferred Stock [Member]
Preferred Stock, par value	$ 0.001	$ 0.001
Preferred Stock, shares authorized	129,767	129,767
Preferred Stock, shares issued	0	0
Preferred Stock, shares outstanding	0	0

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Revenue
Revenues	$ 46,886	$ 975	$ 142,265	$ 3,865
Operating expenses
Cost of goods sold - product revenue	505	41	1,852	365
Research and development - licenses acquired	300	1,000	3,394	3,143
General and administrative	12,318	7,620	28,827	21,202
Total operating expenses	79,489	17,221	215,638	50,338
Loss from operations	(32,603)	(16,246)	(73,373)	(46,473)
Other income (expenses)
Interest income	204	89	530	241
Interest expense and financing fee	(3,220)	(689)	(5,298)	(1,838)
Change in fair value of derivative liabilities	(639)	(16)	5,155	(105)
Change in fair value of subsidiary convertible note	(74)	(13)	(359)	(13)
Change in fair value of investments	270	(81)	(241)	(1,800)
Other expenses	(245)	0	(232)	0
Total other income (expenses)	(3,704)	(710)	(445)	(3,515)
Net loss	(36,307)	(16,956)	(73,818)	(49,988)
Less: net loss attributable to non-controlling interests	9,191	3,975	17,355	12,324
Net loss attributable to common stockholders	$ (27,116)	$ (12,981)	$ (56,463)	$ (37,664)
Basic and diluted net loss per common share	$ (0.67)	$ (0.32)	$ (1.39)	$ (0.94)
Weighted average common shares outstanding-basic and diluted	40,724,115	40,128,475	40,547,364	39,885,685
Parent Company [Member]
Revenue
Product revenue, net	$ 2,170	$ 429	$ 8,309	$ 1,793
Revenue - from a related party	350	546	1,393	2,072
Revenues	2,520	975	9,702	3,865
Operating expenses
Cost of goods sold - product revenue	505	41	1,852	365
Research and development	15,890	7,316	34,683	21,416
Research and development - licenses acquired	300	1,000	3,394	3,143
General and administrative	15,104	8,864	36,490	25,414
Total operating expenses	31,799	17,221	76,419	50,338
National Holdings Corporation [Member]
Revenue
Commissions	24,881	0	73,380	0
Net dealer inventory gains	1,789	0	6,666	0
Investment banking	8,942	0	26,595	0
Investment advisory	3,605	0	10,480	0
Interest and dividends	674	0	2,065	0
Transfer fees and clearing services	1,649	0	5,834	0
Tax preparation and accounting	2,527	0	6,527	0
Other	299	0	1,016	0
Revenues	44,366	0	132,563	0
Operating expenses
Commissions, compensation and fees	39,963	0	118,983	0
Clearing fees	470	0	1,826	0
Communications	690	0	2,094	0
Occupancy	972	0	2,916	0
Licenses and registration	391	0	1,223	0
Professional fees	1,082	0	3,336	0
Interest	5	0	13	0
Depreciation and amortization	507	0	1,513	0
Other administrative expenses	3,610	0	7,315	0
Total operating expenses	$ 47,690	$ 0	$ 139,219	$ 0

Condensed Consolidated Stateme5

Condensed Consolidated Statement of Changes in Stockholders' Equity - 9 months ended Sep. 30, 2017 - USD ($) $ in Thousands	Total	Common Stock [Member]	Common Shares Issuable [Member]	Additional Paid-In Capital [Member]	Accumulated Deficit [Member]	Non-Controlling Interests [Member]
Balance at Dec. 31, 2016	$ 82,968	$ 49	$ 0	$ 283,697	$ (245,251)	$ 44,473
Balance (in shares) at Dec. 31, 2016		48,932,023
Exercise of options for cash	$ 27	$ 0	0	27	0	0
Exercise of options for cash (in shares)	20,000	20,000
Stock-based compensation expense	$ 12,048	$ 0	0	12,048	0	0
Issuance of restricted stock	0	$ 2	0	(2)	0	0
Issuance of restricted stock (in shares)		1,565,020
Issuance of subsidiaries' common shares for license expenses	1,762	$ 0	0	1,762	0	0
Issuance of common stock under ESPP	42	$ 0	0	42	0	0
Issuance of common stock under ESPP (in shares)		22,076
Subsidiaries' offering, net	94,645	$ 0	0	94,645	0	0
Debt discount related to Opus Credit Facility	201	0	0	201	0	0
Issuance of warrants by subsidiary in conjunction with NSC debt	750	0	0	750	0	0
Issuance of warrants in connection with 2017 promissory notes	1,784	0	0	1,784	0	0
Conversion of subsidiaries notes payable	314	0	0	314	0	0
Common shares issuable to NSC interest expense	353	0	353	0	0	0
Common shares issued to NSC interest expense	189	$ 0	0	189	0	0
Common shares issued to NSC interest expense (in shares)		45,818
Non-controlling interest in subsidiaries'	0	$ 0	0	(57,203)	0	57,203
Net loss attributable to non-controlling interest	(17,355)	0	0	0	0	(17,355)
Net loss attributable to common stockholders	(56,463)	0	0	0	(56,463)	0
Balance at Sep. 30, 2017	$ 121,265	$ 51	$ 353	$ 338,254	$ (301,714)	$ 84,321
Balance (in shares) at Sep. 30, 2017		50,584,937

Condensed Consolidated Stateme6

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017		Sep. 30, 2016
Cash Flows from Operating Activities:
Net Loss	$ (73,818)		$ (49,988)
Reconciliation of net loss to net cash used in operating activities:
Depreciation expense	819		240
Amortization expense of intangible asset	1,235		0
Amortization of debt discount	1,316		586
Amortization of product revenue license fee	401		50
Amortization of forgivable loans to registered representatives	520		0
Amortization of deferred clearing credit	(157)		0
Stock-based compensation expense	12,048		8,792
Recovery for doubtful accounts	(274)		0
Common shares issuable to NSC interest expense	353		0
Common shares issued to NSC interest expense	189		0
Change in fair value of investments	241		1,800
Change in fair value of derivative liabilities	(5,155)		105
Change in fair value of subsidiary convertible note	359		13
Loss on write off of investment	250		0
Research and development-licenses acquired, expense	3,394		3,143
Non-cash research and development expense	50		0
Change in fair value of subsidiaries’ assets and liabilities	1,341		491
Increase (decrease) in cash and cash equivalents resulting from changes in operating assets and liabilities:
Restricted cash	(1,026)		0
Cash deposits with clearing organizations	(10)		0
Accounts receivable	(3,752)		(118)
Receivables from broker-dealers and clearing organizations	(4,925)		0
Forgivable loans receivable	(77)		0
Securities owned, at fair value	762		0
Inventory	(115)		(123)
Other receivables - related party	1,152		(1,389)
Prepaid expenses and other current assets	(1,426)		(797)
Accounts payable and accrued expenses	4,195		5,364
Accrued expense - related party	84		0
Securities sold, but not yet purchased, at fair value	(298)		0
Deferred Revenue	680		0
Interest payable	22		41
Interest payable - related party	430		0
Other long-term liabilities	(288)		3,948
Net cash used in operating activities	(61,480)		(27,842)
Cash Flows from Investing Activities:
Purchase of research and development licenses	(965)		(3,095)
Purchase of property and equipment	(999)		(5,756)
Purchase of license	0		(350)
Purchase of short-term investment (certificates of deposit)	(44,088)	[1]	0
Security deposits refund	42		0
Security deposits collected	0		(5)
Acquisition of business - National	(19)		4,626
Collection on notes receivable - disposal of Gilman branches	28		0
Investment in Origo Acquisition Corp.	0		(175)
Net cash used in investing activities	(46,001)		(4,755)
Cash Flows from Financing Activities:
Proceeds from subsidiaries' offering	94,645		11,652
Proceeds from at-the-market offering	0		434
Payment of cost related to at-the-market offering	0		(49)
Proceeds from NSC note	28,355		0
Payment of debt issuance costs associated with NSC Note	(1,081)		0
Payment of NSC note	(3,608)		(2,792)
Proceeds from exercise of stock options	27		0
Proceeds from issuance of common stock under ESPP	42		81
Proceeds from subsidiaries' Convertible Note	9,914		3,018
Payment of debt issuance costs associated with subsidiaries' Convertible Note	(1,071)		(392)
Proceeds from Opus Credit Facility	2,500		5,000
Proceeds from IDB Note	0		920
Transfer of restricted cash	0		(920)
Net cash provided by financing activities	129,723		16,952
Net increase (decrease) in cash and cash equivalents	22,242		(15,645)
Cash and cash equivalents at beginning of period	88,294		98,182
Cash and cash equivalents at end of period	110,536		82,537
Supplemental disclosure of cash flow information:
Cash paid for interest	345		238
Supplemental disclosure of non-cash financing and investing activities:
Issuance of restricted stock	2		2
Issuance of warrants by subsidiary in conjunction with NSC debt	750		634
Issuance of warrants in connection with 2017 Subordinated Note Financing	1,784		0
Debt discount related to Opus Credit Facility	201		0
Beneficial conversion feature related to Opus Credit Facility	0		1,881
Unpaid debt offering cost	42		0
Common shares issuable for license acquired	1,682		0
Conversion of subsidiaries notes payable	314		0
Acquisition of NHLD	0		(21,739)
Goodwill	0		(4,889)
Accounts receivable	0		(1,030)
Receivables from broker dealers and clearing organizations	0		(1,607)
Securities owned, at fair value	0		(2,178)
Prepaid expenses and other current assets	0		(1,985)
Property and equipment, net	0		(1,132)
Restricted cash	0		(353)
Accounts payable and accrued expenses	0		6,079
Accrued commissions and payroll payable	0		14,029
Deferred clearing and marketing credits	0		1,007
Other current liabilities			707
Non-controlling interest	0		17,717
Net cash acquired in the acquisition of NHLD	0		4,626
Cash paid	19		0
Business acquired:
Identifiable intangible asset acquired	211		0
Contingent consideration payable	(192)		0
National [Member]
Supplemental disclosure of cash flow information:
Cash paid for interest	11		16
Cash paid for income taxes	1,004		76
Business acquired:
Fixed assets (acquired but not paid)	$ 665		$ 0

[1]	In connection with Mustang’s manufacturing facility, Mustang incurred $0.1 million related to the design of the facility as of September 30, 2017.

Organization and Description of

Organization and Description of Business	9 Months Ended
Organization and Description of Business	Sep. 30, 2017
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Organization and Description of Business	1. Organization and Description of Business Fortress Biotech, Inc. (“Fortress” or the “Company”) is a biopharmaceutical company dedicated to acquiring, developing and commercializing novel pharmaceutical and biotechnology products. Fortress develops and commercializes products both within Fortress and through certain of its subsidiary companies, also referred to as the “Fortress Companies.” Additionally, the Company has a controlling interest in National Holdings Corporation, a diversified independent brokerage company (together with its subsidiaries, referred to as “NHLD” or “National”). In addition to its internal development programs, the Company leverages its biopharmaceutical business expertise and drug development capabilities and provides funding and management services to help the Fortress Companies achieve their goals. The Company and the Fortress Companies may seek licenses, acquisitions, partnerships, joint ventures and/or public and private financings (including financings facilitated by NHLD) to accelerate and provide additional funding to support their research and development programs and the commercialization of biopharmaceutical products. As of September 30, 2017, in addition to NHLD, the Company has several consolidated Fortress Companies, some of which contain product licenses, including Avenue Therapeutics, Inc. (“Avenue”), Aevitas Therapeutics, Inc (“Aevitas”), Cellvation, Inc. (“Cellvation”), Journey Medical Corporation (“Journey or “JMC”), Coronado SO Co. (“Coronado SO”), Checkpoint Therapeutics, Inc. (“Checkpoint”), Mustang Bio, Inc. (“Mustang”), Helocyte, Inc. (“Helocyte”), Escala Therapeutics, Inc. (“Escala”), CB Securities Corporation (which holds investments classified as cash and cash equivalents), Caelum Biosciences, Inc. (“Caelum”) and Cyprium Therapeutics, Inc. (“Cyprium”). In addition to the foregoing companies, Fortress also maintains ownership positions in subsidiaries with minimal activity, including Innmune Limited.

Summary of Significant Accounti

Summary of Significant Accounting Policies	9 Months Ended
Summary of Significant Accounting Policies	Sep. 30, 2017
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	2. Summary of Significant Accounting Policies The accompanying unaudited interim condensed consolidated financial statements have been prepared in accordance with generally accepted accounting principles in the United States of America (“GAAP”) for interim financial information and the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by GAAP for complete financial statements. In the opinion of management, the unaudited interim condensed consolidated financial statements reflect all adjustments, which include only normal recurring adjustments necessary for the fair statement of the balances and results for the periods presented. Certain information and footnote disclosures normally included in the Company’s annual financial statements prepared in accordance with GAAP have been condensed or omitted. These condensed consolidated financial statement results are not necessarily indicative of results to be expected for the full fiscal year or any future period. The unaudited condensed consolidated financial statements and related disclosures have been prepared with the presumption that users of the unaudited condensed consolidated financial statements have read or have access to the audited consolidated financial statements for the preceding fiscal year for each of the Company, Avenue, Checkpoint, Mustang and National. Accordingly, these unaudited condensed consolidated financial statements should be read in conjunction with the Company’s Form 10-K, which was filed with the United States Securities and Exchange Commission (“SEC”) on March 16, 2017, from which the Company derived the balance sheet data at December 31, 2016, as well as National’s Form 10-K, filed with SEC on December 29, 2016 and their Form 10-Q, filed with the SEC on August 14, 2017, Checkpoint’s Forms 10-K and 10-K/A, filed with the SEC on March 17, 2017 and March 21, 2017, respectively, Mustang’s Form 10-K, filed with the SEC on March 31, 2017, and Avenue’s Form 10-12G/A, filed with the SEC on March 27, 2017. The Company’s unaudited condensed consolidated financial statements include the accounts of the Company and its subsidiaries: NHLD, Innmune Limited, Coronado SO, Cyprium, Escala, JMC, CB Securities Corporation, Avenue, Checkpoint, Mustang, Helocyte, Cellvation, Caelum and Aevitas. All intercompany balances and transactions have been eliminated. The National assets acquired and liabilities assumed and revenues and expenses are reported on a one quarter lag. Therefore, the National assets acquired and liabilities assumed included in these consolidated financial statements as of September 30, 2017 are actually the assets and liabilities as of June 30, 2017 and the revenues and expenses included in these consolidated financial statements for the quarter ending September 30, 2017 are actually the revenues and expenses for the quarter ending June 30, 2017. The preparation of the Company’s unaudited condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the unaudited condensed consolidated financial statements and the reported amounts of expenses during the reporting period. The Company’s unaudited condensed consolidated financial statements include certain amounts that are based on management’s best estimates and judgments. The Company’s significant estimates include, but are not limited to, useful lives assigned to long-lived and intangible assets, fair value measurements, stock-based compensation, common stock issued to acquire licenses, investments, accrued expenses, derivative warrant liabilities, provisions for income taxes and contingencies. Due to the uncertainty inherent in such estimates, actual results may differ from these estimates. There have been no material changes to the Company’s significant accounting policies previously disclosed in the Company’s Form 10-K filed with the SEC on March 16, 2017, with the exception of the policies listed below. The Company considers all short-term investments with an original maturity of three months or less when purchased to be cash equivalents. Cash and cash equivalents at September 30, 2017 and at December 31, 2016 consisted of cash, money market funds and certificates of deposit in institutions in the United States. Balances at certain institutions have exceeded Federal Deposit Insurance Corporation insured limits and U.S. government agency securities. The company classifies its certificates of deposit as cash and cash equivalents or held to maturity in accordance with the Financial Accounting Standards Board ("FASB") Accounting Standards Codification (“ASC”) 320, Investments Debt and Equity Securities At September 30, 2017, the Company had approximately $ 60.1 250,000 16.0 44.1 In March 2016, the FASB issued Accounting Standards Update ("ASU") 2016-09, Compensation-Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting In January 2017, the FASB issued ASU 2017-04, Intangibles - Goodwill and Other (Topic 350): Simplifying the Accounting for Goodwill Impairment In January 2017, the FASB issued ASU 2017-01, Business Combinations (Topic 805): Clarifying the Definition of a Business Recent Accounting Pronouncements In May 2014, the FASB issued ASU 2014-09, Revenue from Contracts with Customers (Topic 606) Revenue from Contracts with Customers (Topic 606): Identifying Performance Obligations and Licensing In January 2016, the FASB issued ASU 2016-01, Financial Instruments - Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Liabilities In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842). In June 2016, the FASB issued ASU 2016-13, Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments In August 2016, the FASB issued ASU 2016-15, Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments, Statement of Cash Flows (Topic 230): Restricted Cash In May 2017, the FASB issued ASU 2017-09, Compensation-Stock Compensation (Topic 718): Scope of Modification Accounting In July 2017, the FASB issued ASU 2017-11, Earnings Per Share (Topic 260), Distinguishing Liabilities from Equity (Topic 480) and Derivatives and Hedging (Topic 815): I. Accounting for Certain Financial Instruments with Down Round Features; II. Replacement of the Indefinite Deferral for Mandatorily Redeemable Financial Instruments of Certain Nonpublic Entities and Certain Mandatorily Redeemable Noncontrolling Interests with a Scope Exception

National Holdings Corporation A

National Holdings Corporation Acquisition - Intangible Assets	9 Months Ended
	Sep. 30, 2017
Business Combinations [Abstract]
National Holdings Corporation Acquisition - Intangible Assets	3. National Holdings Corporation Acquisition Intangible Assets On September 9, 2016, the Company, purchased approximately 56.6 0.02 3.25 In connection with the purchase, the Company recognized $ 18.6 Intangible assets consist of trademark and customer lists acquired in the offer under the purchase method of accounting and are recorded at fair value net of accumulated amortization since the purchase date. Useful life Trademark 10 years Customer lists 10 years The carrying amount related to acquired intangible assets as of September 30, 2017 are as follows ($ in thousands): Intangible assets at December 31, 2016 $ 15,991 Amortization expense (1,235) Intangible assets at September 30, 2017 $ 14,756 Total Three Months Ended December 31, 2017 $ 415 Year Ended December 31, 2018 1,649 Year Ended December 31, 2019 1,649 Year Ended December 31, 2020 1,654 Year Ended December 31, 2021 1,649 Thereafter 7,740 Total $ 14,756 The Company reviews its finite-lived intangible assets for impairment when events or changes in circumstances indicate that the carrying amount of a finite-lived intangible asset may not be recoverable. Recoverability of a finite-lived intangible asset is measured by a comparison of its carrying amount to the undiscounted future cash flows expected to be generated by the asset. If the asset is considered to be impaired, the impairment recognized is measured by the amount by which the carrying amount of the asset exceeds the fair value of the asset. There were no indicators of impairment during the nine months ended September 30, 2017.

Broker-Dealers and Clearing Org

Broker-Dealers and Clearing Organizations, Other Receivables and Prepaid Expenses and Other Current Liabilities	9 Months Ended
	Sep. 30, 2017
Brokers and Dealers [Abstract]
Broker-Dealers and Clearing Organizations, Other Receivables and Prepaid Expenses and Other Current Liabilities	4. Broker-Dealers and Clearing Organizations, Other Receivables and Prepaid Expenses and Other Current Liabilities At June 30, 2017, National’s receivables of $ 2.8 6.0 0.5

Forgivable Loans Receivable

Forgivable Loans Receivable	9 Months Ended
Forgivable Loans Receivable	Sep. 30, 2017
Forgivable Loans Receivable [Abstract]
Forgivable Loans Receivable	5. Forgivable Loans Receivable From time to time, National's operating subsidiaries may make loans, evidenced by promissory notes, primarily to newly recruited independent financial advisors as an incentive for their affiliation. The notes receivable balance is comprised of unsecured non-interest-bearing and interest-bearing loans (interest ranging up to 9 National provides an allowance for doubtful accounts on the notes based on historical collection experience and continually evaluates the receivables for collectability and possible write-offs where a loss is deemed probable. As of June 30, 2017, no allowance for doubtful accounts was required. There were no unamortized forgivable loans outstanding at June 30, 2017 attributable to registered representatives who ended their affiliation with National’s subsidiaries prior to the fulfillment of their obligation.

Property and Equipment

Property and Equipment	9 Months Ended
Property and Equipment	Sep. 30, 2017
Property, Plant and Equipment [Abstract]
Property and Equipment	6. Property and Equipment Estimated Useful September 30, December 31, Lives (in years) 2017 2016 Computer equipment 3 $ 523 $ 440 Furniture and fixtures 5 1,002 821 Leasehold improvements Various 5,351 5,396 Construction in process (1) N/A 139 - Total property and equipment 7,015 6,657 Less: accumulated depreciation (986) (445) Property and equipment, net $ 6,029 $ 6,212 (1) In connection with Mustang’s manufacturing facility, Mustang incurred $ 0.1 Fortress's depreciation expense for the three months ended September 30, 2017 and 2016, was approximately $ 0.2 0.2 0.5 0.2 Estimated Useful June 30, Lives (in years) 2017 Equipment 5 $ 1,305 Furniture and fixtures 5 240 Leasehold improvements Lesser of useful life or term of lease 685 Capital leases (primarily composed of computer equipment) 5 276 Total property and equipment 2,506 Less: accumulated depreciation (314) Property and equipment, net $ 2,192

Fair Value Measurements

Fair Value Measurements	9 Months Ended
Fair Value Measurements	Sep. 30, 2017
Fair Value Disclosures [Abstract]
Fair Value Measurements	7. Fair Value Measurements Certain of the Company’s financial instruments are not measured at fair value on a recurring basis but are recorded at amounts that approximate their fair value due to their liquid or short-term nature, such as accounts payable, accrued expenses and other current liabilities. Laser Device for Treatment of Migraine Headache On March 17, 2014, the Company invested $ 0.3 million 35 13,409,962 83 16,091,954 0.3 0.3 Origo Acquisition Corporation (formerly CB Pharma Acquisition Corporation) On December 19, 2016, Origo Acquisition Corporation (“Origo”) entered into a merger agreement (“Origo Merger Agreement”) with Aina Le’a Inc. (“Aina Le’a”), a residential and commercial real estate developer in Hawaii. On February 17, 2017, Origo sent a termination letter, as supplemented on February 22, 2017, to Aina Le’a terminating the Origo Merger Agreement. On March 10, 2017, Origo’s shareholders approved an amendment to Origo’s organizational documents extending the date by which Origo must consummate a merger to September 12, 2017. On September 11, 2017, Origo’s shareholders approved a second amendment to the Articles of Association and extended the date by which to consummate a business combination to March 12, 2018. On July 24, 2017, Origo entered into a Merger Agreement with High Times Holding Corp. (“HTH”), which was later amended on September 27, 2017 (“Amended Merger Agreement”). Pursuant to the terms of the Amended Merger Agreement, the Merger Sub will merge with and into HTH, with HTH continuing as the surviving entity (the “Merger”) and all holders of HTH equity securities and warrants, options and rights to acquire or securities that convert into HTH equity securities (collectively, “HTH Securities”) will convert into Origo common shares and, with respect to options, options to acquire Origo common shares. The Merger Agreement also provides that, immediately prior to the Effective Time, Origo will reincorporate under the laws of the State of Nevada, whether by reincorporation, statutory conversion or otherwise. As of September 30, 2017, the Company valued its investment in Origo, a publicly traded company, utilizing the following assumptions: probability of a successful business combination of 31.4 10.61 0.33 0.31 0.2 0.9 0.3 Contingently Issuable Warrant Pursuant to the Company’s promissory note with NSC of March 2015, as amended in July 2015 (the “NSC Note”), (see Note 11), if the Company transfers any proceeds from the NSC Note to a Fortress Company, such Fortress Company will issue to NSC Biotech Venture Fund I LLC a new promissory note on identical terms as the NSC Note and NSC Biotech Venture Fund I LLC will also receive a warrant to purchase a number of shares of such Fortress Company’s stock equal to 25% of the outstanding Fortress Company note divided by the lowest price for which the Fortress Company sells its equity in its first third party financing. The warrants issued will have a term of 10 years and an exercise price equal to the par value of the Fortress Company’s common stock and are accounted for in accordance with ASC 815, Derivatives and Hedging. Avenue classified the fair value of the contingently issuable warrants granted in connection with the transfer from Fortress of $ 3.0 On June 26, 2017, Avenue closed on an Initial Public Offering (“IPO”) raising gross proceeds of $ 38.0 6.3 6.00 3.0 125,000 Avenue’s Contingently Issuable ($ in thousands) Warrants Beginning balance at January 1, 2017 $ 302 Conversion into common shares (750) Change in fair value 448 Ending balance at September 30, 2017 $ - Avenue Warrant Liabilities On December 30, 2016, Avenue held a closing of the sale of convertible promissory notes. In the closing, WestPark Capital, Inc., the placement agent (“WestPark”), received a warrant (the “WestPark Warrant”) to purchase the number of shares of Avenue’s common stock equal to $ 10,000 Additionally, on June 26, 2017, in connection with Avenue’s IPO, Avenue issued 2,488 4.02 33 6.00 Avenue’s Warrant ($ in thousands) Liability Beginning balance at January 1, 2017 $ 12 Conversion into common shares (15) Change in fair value 3 Ending balance at September 30, 2017 $ - Helocyte Warrant Liabilities The fair value of Helocyte’s warrant liability, which was issued in connection with Helocyte’s convertible note (see Note 11), was measured using a Monte Carlo simulation valuation methodology. A summary of the weighted average (in aggregate) significant unobservable inputs (Level 3 inputs) used in measuring Helocyte’s warrant liabilities that are categorized within Level 3 of the fair value hierarchy as of September 30, 2017 is as follows: September 30, 2017 Risk-free interest rate 1.733% 1.795 % Expected dividend yield - % Expected term in years 3.75 4.17 Expected volatility 70.0 % Strike price $ 0.44 ($ in thousands) Fair Value of Beginning balance at January 1, 2017 $ 167 Change in fair value of derivative liabilities (79) Ending balance at September 30, 2017 $ 88 Caelum Warrant Liabilities The fair value of Caelum's warrant liability, which was issued in connection with Caelum’s convertible note (see Note 11), was measured using a Monte Carlo simulation valuation methodology. A summary of the weighted average (in aggregate) significant unobservable inputs (Level 3 inputs) used in measuring Caelum’s warrant liabilities that are categorized within Level 3 of the fair value hierarchy as of September 30, 2017 is as follows: September 30, 2017 Risk-free interest rate 1.895% 1.914 % Expected dividend yield - % Expected term in years 4.84 4.96 Expected volatility 70.0 % Strike price $ 1.43 ($ in thousands) Fair Value of Beginning balance at January 1, 2017 $ - Change in fair value of derivative liabilities 225 Ending balance at September 30, 2017 $ 225 Helocyte Convertible Notes at Fair Value Helocyte’s convertible note is measured at fair value using the Monte Carlo simulation valuation methodology. A summary of the weighted average (in aggregate) significant unobservable inputs (Level 3 inputs) used in measuring Helocyte’s convertible debt that is categorized within Level 3 of the fair value hierarchy as of September 30, 2017 is as follows: September 30, 2017 Risk-free interest rate 1.199% 1.336 % Expected dividend yield - % Expected term in years 0.50 1.16 Expected volatility 59.5 % ($ in thousands) Helocyte Beginning balance at January 1, 2017 $ 4,487 Change in fair value of convertible notes 246 Ending balance at September 30, 2017 $ 4,733 Caelum Convertible Notes at Fair Value Caelum’s convertible debt is measured at fair value using the Monte Carlo simulation valuation methodology. A summary of the weighted average (in aggregate) significant unobservable inputs (Level 3 inputs) used in measuring Caelum’s convertible debt that is categorized within Level 3 of the fair value hierarchy as of September 30, 2017 is as follows: September 30, 2017 Risk-free interest rate 1.246% 1.463 % Expected dividend yield - % Expected term in years 0.71 1.95 Expected volatility 70.0 % Caelum Convertible Note, at fair ($ in thousands) value Beginning balance at January 1, 2017 $ - Additions 9,914 Change in fair value of convertible notes 14 Ending balance at September 30, 2017 $ 9,928 Avenue Convertible Notes at Fair Value On June 26, 2017, upon completion of Avenue’s IPO, Avenue’s convertible debt automatically converted into approximately 49,749 4.02 33 Avenue Convertible Note, at fair ($ in thousands) value Beginning balance at January 1, 2017 $ 200 Conversion into common shares (299) Change in fair value of convertible notes 99 Ending balance at September 30, 2017 $ - Fair Value Measurement as of September 30, 2017 ($ in thousands) Level 1 Level 2 Level 3 Total Assets Long-term investments, at fair value $ - $ - $ 923 $ 923 Total $ - $ - $ 923 $ 923 Liabilities Warrant liabilities $ - $ - $ 313 $ 313 Caelum Convertible Note, at fair value - - 9,928 9,928 Helocyte Convertible Note, at fair value - - 4,733 4,733 Total $ - $ - $ 14,974 $ 14,974 Fair Value Measurement as of December 31, 2016 ($ in thousands) Level 1 Level 2 Level 3 Total Assets Long-term investments, at fair value $ - $ - $ 1,414 $ 1,414 Total $ - $ - $ 1,414 $ 1,414 Liabilities Contingently Issuable Warrants $ - $ - $ 302 $ 302 Warrant liabilities - - 179 179 Helocyte Convertible Note, at fair value - - 4,487 4,487 Avenue Convertible Note, at fair value - - 200 200 Total $ - $ - $ 5,168 $ 5,168 Fair Value Measurement as of June 30, 2017 ($ in thousands) Level 1 Level 2 Level 3 Total Assets National Securities owned, at fair value Corporate stocks $ 70 $ - $ - $ 70 Municipal bonds 816 517 - 1,333 Restricted stock - 192 - 192 Total $ 886 $ 709 $ - $ 1,595 Liabilities National Securities sold, but not yet purchased at fair value Contingent consideration $ - $ - $ 637 $ 637 Warrants - National - 8,832 8,832 Total $ - $ - $ 9,469 $ 9,469 Warrants issuable - National In accordance with the Company’s Merger Agreement with National, since less than 80 3.25 As National does not have the ability to settle the warrants with unregistered shares and maintenance of an effective registration statement may be considered outside of the Company’s control, net cash settlement of the warrants is assumed. The fair value of the 5.4 43.4 June 30, 2017 Dividend yield - % Expected volatility 91 % Risk-free interest rate 1.890 % Life (in years) 4.20 National’s ($ in thousands) Warrants Beginning balance at December 31, 2016 $ 14,359 Change in fair value of derivative liability (5,527) Ending balance at June 30, 2017 $ 8,832 National listed the warrants on the Nasdaq Capital Market under the symbol “NHLDW” in February 2017. Convertible Note, at fair value Contingently Investment in Investment in Issuable Warrant ($ in thousands) Origo laser device Helocyte Avenue Caelum Warrants liabilities Total Balance at December 31, 2016 $ 1,164 $ 250 $ 4,487 $ 200 $ - $ 14,661 $ 179 $ 20,941 Additions during the period - - - - 9,914 - 225 10,139 Conversion into common shares - - - (299) - (750) (15) (1,064) Issuance of warrants - - - - - (8,190) 8,190 - Loss on write off investment - (250) - - - - - (250) Change in fair value of investments (241) - - - - - - (241) Change in fair value of convertible notes - - 246 99 14 - - 359 Change in fair value of derivative liabilities - - - - - (5,079) (76) (5,155) Balance at September 30, 2017 $ 923 $ - $ 4,733 $ - $ 9,928 $ 642 $ 8,503 $ 24,729 For the nine months ended September 30, 2017, no transfers occurred between Level 1, Level 2 and Level 3 instruments.

Licenses Acquired

Licenses Acquired	9 Months Ended
Licenses Acquired	Sep. 30, 2017
Licenses Acquired [Abstract]
Licenses Acquired	8. Licenses Acquired In accordance with ASC 730-10-25-1, Research and Development For the Three Months Ended September 30, For the Nine Months Ended September 30, ($ in thousands) 2017 2016 2017 2016 Fortress $ - $ - $ 300 $ - Fortress Companies: Checkpoint - 1,000 400 3,060 Helocyte - - - 83 Mustang 300 - 2,375 - Caelum - - 219 - Cyprium - - 100 - Total $ 300 $ 1,000 $ 3,394 $ 3,143 Fortress Effcon Laboratories, Inc. In September 2016, the Company entered into a development and license agreement with Effcon Laboratories, Inc. (“Effcon”) for the development of extended release formulation of Methozolamide. Pursuant to the Agreement, Fortress paid an upfront fee of $ 0.2 2.3 1.6 0.3 Checkpoint Jubilant Biosys Limited In May 2016, Checkpoint entered into a license agreement with Jubilant Biosys Limited (“Jubilant”), whereby Checkpoint obtained an exclusive, worldwide license (the “Jubilant License”) to Jubilant’s family of patents covering compounds that inhibit BRD4, a member of the BET domain for cancer treatment, including CK-103. For the nine months ended September 30, 2017, Checkpoint expensed a non-refundable milestone payment of $ 0.4 2.0 In connection with the Jubilant License, Checkpoint entered into a sublicense agreement with TG Therapeutics, Inc. (“TGTX”), a related party, to develop and commercialize the compounds licensed in the field of hematological malignancies, with Checkpoint retaining the right to develop and commercialize these compounds in the field of solid tumors. Michael Weiss, Chairman of the Board of Directors of Checkpoint and the Company’s Executive Vice Chairman, Strategic Development, is also the Executive Chairman, President and Chief Executive Officer and a stockholder of TGTX. For the three months ended September 30, 2017 and 2016, Checkpoint recognized $ 0.2 0.3 0.8 1.3 Dana-Farber Cancer Institute In connection with its license agreement with Dana-Farber, Checkpoint entered into a collaboration agreement with TGTX, a related party, to develop and commercialize the anti-PD-L1 and anti-GITR antibody research programs in the field of hematological malignancies, while Checkpoint retains the right to develop and commercialize these antibodies in the field of solid tumors. Michael Weiss, Chairman of the Board of Directors of Checkpoint and Fortress’s Executive Vice Chairman, Strategic Development, is also the Executive Chairman, President and Chief Executive Officer and a stockholder of TGTX. For the three months ended September 30, 2017 and 2016, approximately $ 46,000 84,000 20,000 Mustang License Agreement with the City of Hope In March 2015, Mustang entered into an exclusive license agreement with City of Hope (“COH”) to acquire intellectual property rights pertaining to chimeric antigen receptor T cells, CAR-T (the “Original License”). On February 17, 2017, Mustang and COH amended and restated the Original License by entering into three separate exclusive license agreements, one relating to CD123 (the “CD123 License”), one relating to IL13Rα2 (the “IL13Rα2 License”) and one relating to the spacer technology (the “Spacer License”). The total potential consideration payable to COH by Mustang under the new license agreements, in equity or cash, did not, in the aggregate, change materially from the Original License. CD123 License Pursuant to the CD123 License, Mustang and COH acknowledge that an upfront fee was paid under the Original License. In addition, an annual maintenance fee will continue to apply. COH is eligible to receive up to approximately $ 14.5 IL13Rα2 License Pursuant to the IL13Rα2 License, Mustang and COH acknowledge that an upfront fee was paid under the Original License. In addition, an annual maintenance fee will continue to apply. COH is eligible to receive up to approximately $ 14.5 0.3 Spacer License Pursuant to the Spacer License, Mustang and COH acknowledge that an upfront fee was paid under the Original License. In addition, an annual maintenance fee will continue to apply. No royalties are due if the Spacer technology is used in conjunction with a CD123 CAR or an IL13Rα2 CAR, and royalty payments in the low single digits are due on net sales of licensed products if the Spacer technology is used in conjunction with other intellectual property. Mustang is obligated to pay COH a percentage (in the mid-thirties) of certain revenues received in connection with a sublicense. In addition, equity grants made under the Original License were acknowledged, and the anti-dilution provisions of the Original License were carried forward. IV/ICV Agreement On February 17, 2017, Mustang entered into an exclusive license agreement (the “IV/ICV Agreement”) with COH to acquire intellectual property rights in patent applications related to the intraventricular and intracerebroventricular methods of delivering T cells that express CARs. Pursuant to the IV/ICV Agreement, Mustang paid COH an upfront fee of $ 0.1 0.1 HER2 Technology License On May 31, 2017, Mustang entered into an exclusive license agreement with the COH for the use of human epidermal growth factor receptor 2 (HER2) CAR T technology (HER2 Technology), which will initially be applied in the treatment of glioblastoma multiforme. Pursuant to the Agreement, Mustang paid an upfront fee of $ 0.6 50,000 14.9 CS1 Technology License On May 31, 2017, Mustang entered into an exclusive license agreement with the COH for the use of CS1 specific CAR T technology (CS1 Technology) to be directed against multiple myeloma. Pursuant to the Agreement, Mustang paid an upfront fee of $ 0.6 50,000 14.9 PSCA Technology License On May 31, 2017, Mustang entered into an exclusive license agreement with the COH for the use of prostate stem cell antigen (PSCA) CAR T technology (PSCA Technology) to be used in the treatment of prostate cancer. Pursuant to the Agreement, Mustang paid an upfront fee of $ 0.3 50,000 14.9 License with University of California On March 17, 2017, Mustang entered into an exclusive license agreement with the Regents of the University of California (“UCLA License”) to acquire intellectual property rights in patent applications related to the engineered anti-prostate stem cell antigen antibodies for cancer targeting and detection. Pursuant to the UCLA Agreement, Mustang paid UCLA an upfront fee of $ 0.2 14.3 Fred Hutchinson Cancer Research Center License On July 3, 2017, Mustang entered into an exclusive, worldwide licensing agreement with Fred Hutchinson Cancer Research Center (“Fred Hutch”) for the use of a CAR T therapy related to autologous T cells engineered to express a CD20-specific chimeric antigen receptor (“CD 20 Technology License”). Pursuant to the CD 20 Technology License, Mustang paid Fred Hutch an upfront fee of $ 0.3 50,000 39.1 Caelum License Agreement with Columbia University In January 2017, Caelum entered into an exclusive license agreement with Columbia University (“Columbia”) to secure worldwide license rights to CAEL-101 (11-1F4), a chimeric fibril-reactive monoclonal antibody (mAb) being evaluated in a Phase 1a/1b study for the treatment of amyloid light chain (“AL”) amyloidosis. This transaction was accounted for as an asset acquisition pursuant to ASU 2017-01, Business Combinations (Topic 805): Clarifying the Definition of a Business, . 0.2 1,050,000 10 29,000 0.028 5.5 Cyprium License Agreement with the Eunice Kennedy Shriver In March 2017, Cyprium and the Eunice Kennedy Shriver Business Combinations (Topic 805): Clarifying the Definition of a Business, . 0.1

Intangibles, net

Intangibles, net	9 Months Ended
Intangibles, net	Sep. 30, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
Intangibles, net	10. Intangibles, net Journey Pursuant to the terms of Journey’s license agreements for its branded products, Journey made upfront payments totaling $ 1.6

Debt and Interest

Debt and Interest	9 Months Ended
Debt and Interest	Sep. 30, 2017
Debt Disclosure [Abstract]
Debt and Interest	11. Debt and Interest Debt September 30, December 31, ($ in thousands) 2017 2016 Interest rate Maturity IDB Note $ 14,929 $ 14,929 2.25 % Feb - 2018 NSC Note - 3,608 8.00 % Sep - 2018 2017 Subordinated Note Financing 3,254 - 8.00 % March - 2020 2017 Subordinated Note Financing 13,893 - 8.00 % May - 2020 2017 Subordinated Note Financing 1,820 - 8.00 % June - 2020 2017 Subordinated Note Financing 3,017 - 8.00 % August - 2020 2017 Subordinated Note Financing 6,371 - 8.00 % September - 2020 Opus Credit Facility 9,500 7,000 12.00 % Sep - 2018 Helocyte Convertible Note, at fair value 1,084 1,031 5.00% - 8.00 % December 2017 Helocyte Convertible Note, at fair value 2,164 2,051 5.00% - 8.00 % March - 2018 Helocyte Convertible Note, at fair value 1,049 991 5.00% - 8.00 % April - 2018 Helocyte Convertible Note, at fair value 436 414 5.00% - 8.00 % May - 2018 Avenue Convertible Note, at fair value - 200 5.00% - 8.00 % June - 2018 Caelum Convertible Note, at fair value 1,004 - 8.00 % January - 2019 Caelum Convertible Note, at fair value 6,810 - 8.00 % February -2019 Caelum Convertible Note, at fair value 2,114 - 8.00 % June - 2019 Total notes payable 67,445 30,224 Less: Discount on notes payable 3,827 2,009 Total notes payable $ 63,618 $ 28,215 IDB Note On February 13, 2014, the Company executed a secured promissory note in favor of Israel Discount Bank of New York (“IDB”) in the amount of $ 15.0 14.9 15.0 NSC Note On July 5, 2017, the Company repaid it NSC Note in the amount of $3.6 million. 2017 Subordinated Note Financing On March 31, 2017, the Company entered into Note Purchase Agreements (the “Purchase Agreements”) with NAM Biotech Fund II, LLC I (“NAM Biotech Fund”) and NAM Special Situations Fund I QP, LLC (“NAM Special Situations Fund”), both of which are accredited investors, and sold subordinated promissory notes (the “Notes”) of the Company (the “2017 Subordinated Note Financing”) in the aggregate principal amount of $ 3.25 8 7 Each Note is due on the third anniversary of its issuance, provided that the Company may extend the maturity date for two one-year periods in its sole discretion 40.0 50.0 National Securities Corporation (“NSC”), a subsidiary of National and a related party, (see Note 17), pursuant to a Placement Agency Agreement entered into between the Company, NAM Biotech Fund and NSC (the “NAM Placement Agency Agreement”) and a Placement Agency Agreement entered into between the Company, NAM Special Situations Fund and NSC (together with the NAM Placement Agency Agreement, the “Placement Agency Agreements”) acts as placement agent in the 2017 Subordinated Note Financing. Pursuant to the terms of the Placement Agency Agreements, NSC receives (in addition to reimbursement of certain expenses) an aggregate cash fee equal to 10 10 On March 31, 2017, held its first closing of the 2017 Subordinated Note Financing and received a gross proceeds of $ 3.2 87,946 On May 1, 2017, the Company held a second closing of the 2017 Subordinated Note Financing and received gross proceeds of $ 8.6 0.9 234,438 3.65 On May 31, 2017, the Company held a third closing of the 2017 Subordinated Note Financing and received gross proceeds of $ 5.3 0.5 147,806 3.61 On June 30, 2017, the Company held a fourth closing of the 2017 Subordinated Note Financing and received gross proceeds of $ 1.8 0.2 38,315 4.75 On August 31, 2017, the Company held a fifth closing of the 2017 Subordinated Note Financing and received gross proceeds of $ 3.0 0.3 63,526 4.75 On September 30, 2017, the Company held a sixth closing of the 2017 Subordinated Note Financing and received gross proceeds of $ 6.4 0.6 144,149 4.42 Caelum Convertible Notes On July 31, 2017 Caelum through National Securities Corporation (“NSC” or “Placement Agent”), a subsidiary of National offered up to $ 10 10 For the three months ended September 30, 2017, Caelum raised $ 9.9 0.9 10 110 the exercise price will be $75 million dollars divided by the total number of fully-diluted shares of Common Stock outstanding immediately prior to exercise of the warrant, giving effect to the assumed conversion of all options, warrants, and convertible securities of the Company The notes convert upon a qualified financing in which Caelum raises gross proceeds of at least $10 million as follows: the lesser of (a) a discount to the price per common share being paid in the Sale of the Company equal to 20% or (b) a conversion price per share based on a pre-sale valuation of $75,000,000 divided by the number of common shares outstanding at that time assuming the hypothetical conversion or exercise of any convertible securities, options, warrants and other rights to acquire common shares of the Company Opus Credit Facility As of September 30, 2017, the Company had $ 9.5 1.3 Interest Expense For the Three Months Ended For the Nine Months Ended September 30, September 30, ($ in thousands) 2017 2016 2017 2016 IDB Note Interest $ 85 $ 84 $ 254 $ 243 Amortization of fees - - - 1 Total IDB Note 85 84 254 244 NSC Debt Interest (8) 145 147 456 Amortization of fees 127 135 200 557 Total NSC Debt 119 280 347 1,013 2017 Subordinated Note Interest 755 - 1,161 - Amortization of fees 208 - 383 - Total 2017 Subordinated Note 963 - 1,544 - Opus Credit Facility Interest 287 26 798 26 Amortization of fees 282 28 733 28 Total Opus Note 569 54 1,531 54 LOC Fees Interest 7 3 22 10 Total LOC 7 3 22 10 Helocyte Convertible Note Interest 64 26 175 26 Financing fee - 242 1 491 Total Helocyte Convertible Note 64 268 176 517 Avenue Convertible Note Interest - - 5 - Financing fee - - 3 - Total Avenue Convertible Note - - 8 - Caelum Convertible Note Interest 68 - 68 - Financing fee 1,317 - 1,317 - Total Caelum Convertible Note 1,385 - 1,385 - Falk CSR Interest 26 - 26 - Total Falk CSR 26 - 26 - D&O Insurance Interest 2 - 5 - Total D&O Insurance 2 - 5 - Total Interest Expense and Financing Fee $ 3,220 $ 689 $ 5,298 $ 1,838

Accrued Expenses and Other Long

Accrued Expenses and Other Long-Term Liabilities	9 Months Ended
Accrued Expenses and Other Long-Term Liabilities	Sep. 30, 2017
Payables and Accruals [Abstract]
Accrued Expenses and Other Long-Term Liabilities	12. Accrued Expenses and Other Long-Term Liabilities September 30, December 31, ($ in thousands) 2017 2016 Accrued expenses: Professional fees $ 1,297 $ 1,253 Salaries, bonuses and related benefits 4,178 2,846 Accrued Severance - 53 Accrued Legal Settlement (1) 2,212 - Ovamed manufacturing rights - short term component - 900 Research and development 3,311 394 Dr. Falk Pharma milestone 2,950 2,634 Other 2,703 2,002 Total accrued expenses $ 16,651 $ 10,082 Other long-term liabilities: Deferred rent and long-term lease abandonment charge 4,736 5,014 Total other long-term liabilities $ 4,736 $ 5,014 (1) In connection with a legal settlement (see Note 16), the Company is required to deliver 200,000 Contingencies, 2.0 June 30, 2017 Legal $ 836 Audit 148 Telecommunications 196 Data Services 450 Regulatory 661 Settlements 2,633 Deferred rent 177 Contingent consideration payable 636 Income taxes payable 927 Other 1,844 Total $ 8,508

Non-Controlling Interests

Non-Controlling Interests	9 Months Ended
Non-Controlling Interests	Sep. 30, 2017
Noncontrolling Interest [Abstract]
Non-Controlling Interests	13. Non-Controlling Interests As of September 30, 2017 ($ in thousands) Avenue Coronado SO Mustang Checkpoint JMC Helocyte Cellvation Caelum Aevitas National Total NCI equity share $ 17,306 $ (236) $ 47,840 $ 22,368 $ (535) $ (1,848) $ (239) $ 7 $ (9) $ 17,022 $ 101,676 Net loss attributed to non-controlling interests (1,329) (22) (8,268) (10,144) (150) (975) (60) (1,086) (166) 4,845 (17,355) Non-controlling interests in consolidated entities $ 15,977 $ (258) $ 39,572 $ 12,224 $ (685) $ (2,823) $ (299) $ (1,079) $ (175) $ 21,867 $ 84,321 As of December 31, 2016 ($ in thousands) Avenue Coronado SO Mustang Checkpoint JMC Helocyte Cellvation National Total NCI equity share $ (494) $ (217) $ 12,376 $ 32,160 $ (192) $ (612) $ 4 $ 17,643 $ 60,668 Net loss attributed to non-controlling interests (349) (19) (1,805) (11,733) (355) (1,155) (158) (621) (16,195) Non-controlling interests in consolidated entities $ (843) $ (236) $ 10,571 $ 20,427 $ (547) $ (1,767) $ (154) $ 17,022 $ 44,473 For the three months ended September 30, 2017 ($ in thousands) Avenue (2) Coronado Mustang (2) Checkpoint JMC Helocyte Cellvation Caelum Aevitas National Total Non-controlling interests in loss of consolidated entities $ (1,015) $ (15) $ (3,241) $ (3,437) $ (103) $ (376) $ 24 $ (835) $ (166) $ (27) $ (9,191) Non-controlling ownership 66.1 % 13.0 % 60.8 % 61.9 % 6.9 % 20.0 % 22.0 % 25.2 % 25.3 % 43.4 % For the nine months ended September 30, 2017 ($ in thousands) Avenue Coronado Mustang Checkpoint JMC Helocyte Cellvation Caelum Aevitas National Total Non-controlling interests in loss of consolidated entities $ (1,329) $ (22) $ (8,268) $ (10,144) $ (150) $ (975) $ (60) $ (1,086) $ (166) $ 4,845 $ (16,011) Non-controlling ownership 28.9 % 13.0 % 58.7 % 61.9 % 6.9 % 20.0 % 22.0 % 25.2 % 25.3 % 43.4 % For the three months ended September 30, 2016 ($ in thousands) Avenue Coronado SO Mustang Checkpoint JMC Helocyte Total Non-controlling interests in loss of consolidated entities $ (47) $ (4) $ (204) $ (3,254) $ (104) $ (362) $ (3,975) Non-controlling ownership (3) 10.5 % 13.0 % 23.9 % 62.7 % 8.1 % 20.6 % For the nine months ended September 30, 2016 ($ in thousands) Avenue Coronado SO Mustang Checkpoint JMC Helocyte Total Non-controlling interests in loss of consolidated entities $ (231) $ (14) $ (363) $ (10,767) $ (333) $ (616) $ (12,324) Non-controlling ownership (3) 10.5 % 13.0 % 10.0 % 63.5 %(1) 8.1 % 20.6 % (1) - Checkpoint is consolidated with Fortress’s operations because Fortress maintains voting control through its ownership of Checkpoint’s Class A common shares which provide for super-majority voting rights. (2) - Mustang and Avenue are consolidated with Fortress’s operations because Fortress maintains voting control through its ownership of Mustang’s and Avenue’s Class A preferred shares which provide super-majority voting rights. (3) - Represents a weighted average of ownership during the periods presented.

Net Loss per Common Share

Net Loss per Common Share	9 Months Ended
Net Loss per Common Share	Sep. 30, 2017
Earnings Per Share [Abstract]
Net Loss Per Common Share	14. Net Loss per Common Share Basic net loss per share is calculated by dividing net loss by the weighted-average number of shares of common stock outstanding for the period, without consideration for common stock equivalents. Diluted net loss per share is computed by dividing net loss by the weighted-average number of common stock and common stock equivalents outstanding for the period. The Company’s common stock equivalents, including unvested restricted stock, options, and warrants have been excluded from the computation of diluted net loss per share as the effect would be to reduce the net loss per share. Therefore, the weighted average common stock outstanding used to calculate both basic and diluted net loss per share is the same. Nine Months Ended September 30, 2017 2016 Warrants to purchase Common Stock 678,072 480,559 Opus warrants to purchase Common Stock 206,593 1,700,000 Options to purchase Common Stock 1,095,905 1,769,426 Unvested Restricted Stock 9,848,505 8,763,797 Unvested Restricted Stock Units 1,234,555 1,054,091 Total 13,063,630 13,767,873

Stockholders' Equity

Stockholders' Equity	9 Months Ended
Stockholders' Equity	Sep. 30, 2017
Stockholders' Equity Note [Abstract]
Stockholders’ Equity	15. Stockholders’ Equity Stock-based Compensation excluding National As of September 30, 2017, the Company had four equity compensation plans: the Fortress Biotech, Inc. 2007 Stock Incentive Plan, the Fortress Biotech, Inc. 2013 Stock Incentive Plan, as amended, the Fortress Biotech, Inc. 2012 Employee Stock Purchase Plan and the Fortress Biotech, Inc. Long Term Incentive Plan. Three Months Ended Nine Months Ended September 30, September 30, ($ in thousands) 2017 2016 2017 2016 Employee awards $ 1,650 $ 1,937 $ 5,170 $ 5,490 Non-employee awards 24 3 60 9 Fortress Companies 2,510 (1) 963 (2) 6,506 (3) 3,293 (4) Total stock-based compensation expense $ 4,183 $ 2,903 $ 11,736 $ 8,792 (1) Consists of approximately $ 0.2 0.9 0.8 0.4 62,000 27,000 5,000 (2) 5,000 0.8 130,000 67,000 (3) Consists of approximately $ 0.3 4.3 1.2 0.4 0.2 0.1 19,000 (4) Consists of approximately $ 23,000 2.7 458,000 160,000 For the three months ended September 30, 2017 and 2016, approximately $ 1.6 0.9 2.6 2.0 For the nine months ended September 30, 2017 and 2016, approximately $ 4.8 3.4 6.9 5.4 Weighted average Total weighted remaining Weighted average average intrinsic contractual life Number of shares exercise price value (years) Options vested and expected to vest at December 31, 2016 1,130,501 $ 3.73 $ 602,451 4.93 Exercised (20,000) 1.37 61,000 - Options vested and expected to vest at September 30, 2017 1,100,501 $ 3.78 $ 1,620,046 4.21 Options vested and exercisable 1,085,501 $ 3.75 $ 1,620,046 4.18 As of September 30, 2017, Fortress had no unrecognized stock-based compensation expense related to options. The following table summarizes Fortress’s restricted stock and restricted stock unit award activity, excluding activity related to Fortress Companies (which is discussed below): Weighted average Number of shares grant price Unvested balance at December 31, 2016 10,094,095 $ 2.49 Restricted stock granted 1,325,396 2.70 Restricted stock vested (213,333) 2.75 Restricted stock units granted 930,000 4.31 Restricted stock units forfeited (15,000) 2.98 Restricted stock units vested (214,625) 3.44 Unvested balance at September 30, 2017 11,906,533 $ 2.63 As of September 30, 2017, the Company had unrecognized stock-based compensation expense related to restricted stock and restricted stock unit awards of approximately $ 1.7 5.6 2.0 2.2 5.6 1.2 Employee Stock Purchase Plan Eligible employees can purchase the Company’s Common Stock at the end of a predetermined offering period at 85% of the lower of the fair market value at the beginning or end of the offering period. The ESPP is compensatory and results in stock-based compensation expense. As of September 30, 2017, 199,995 205,000 52,000 35,000 0.1 91,000 22,000 41,900 Warrants Weighted average Total weighted remaining Weighted average average intrinsic contractual life Number of shares exercise price value (years) Outstanding as of December 31, 2016 2,263,453 $ 3.62 $ 79,800 4.74 Granted 816,180 1.33 329,954 4.87 Forfeited (230,444) 8.39 - - Outstanding as of September 30, 2017 2,849,189 $ 2.57 $ 3,358,161 4.69 Exercisable as of September 30, 2017 869,189 $ 3.96 $ 546,561 4.30 Long-Term Incentive Program (“LTIP”) On January 1, 2017 and 2016, the Compensation Committee granted 552,698 510,434 100.0 1.5 1.4 0.2 75,000 0.5 0.2 Additionally, in connection with the LTIP Lindsay Rosenwald and Michael Weiss receive 5% of the outstanding shares of Fortress Companies upon formation. During the nine months ended September 30, 2017, LTIP grants from Aevitas, Caleum and Cyprium were made. For the three months ended September 30, 2017 and 2016, the Company recorded approximately $ 52,000 Fortress Companies Checkpoint Therapeutics, Inc. Checkpoint has a long-term incentive plan under which it has issued grants to both employees and non-employees. For the three months ended September 30, 2017 and 2016, Checkpoint re-measured its non-employee and research and development employee grants and recorded expense of approximately $ 0.4 0.4 2.8 1.6 Certain Checkpoint employees and directors also have been awarded restricted stock under Checkpoint’s 2015 Incentive Plan. Checkpoint recorded stock-based compensation expense of $ 0.5 0.3 1.5 1.0 Avenue Therapeutics, Inc. In connection with stock grants made to both employees and non-employees, Avenue for the three months ended September 30, 2017 and 2016, recorded approximately $ 0.2 3,000 78,000 3,000 0.2 12,000 90,000 12,000 Journey Medical Corporation During the nine months ended September 30, 2017, JMC granted option awards to numerous sales employees exercisable for 395,000 The fair value of stock options granted was determined on the grant date using assumptions for risk free interest rate, the expected term, expected volatility, and expected dividend yield. The stock price was determined utilizing a discounted cash flow model to determine the weighted market value of invested capital. JMC does not expect to pay dividends in the foreseeable future. As a result, the expected dividend yield is 0%. The expected term for stock options granted with service conditions represents the average period the stock options are expected to remain outstanding and is based on the expected term calculated using the approach prescribed by the SEC's Staff Accounting Bulletin No. 110 for “plain vanilla” options. JMC obtained the risk-free interest rate from publicly available data published by the Federal Reserve. The volatility rate was computed based on a comparison of average volatility rates of similar companies. September 30, 2017 Risk-free interest rate 1.88% - 2.22 % Expected dividend yield - % Expected term in years 5.0 7.0 Expected volatility 107 % During the three and nine months ended September 30, 2017, stock-based compensation associated with the amortization of stock option expenses was approximately 8,000 29,000 95,000 25,000 Mustang The employment agreement grants Dr. Litchman an option to purchase 1,041,675 5.73 On April 7, 2017, Mustang granted 200,000 5.73 Both grants have the following vesting schedule: 50% of the options vest over-time with 25% vesting over 12 months of continued service, with the remaining 25% vesting in 12 equal installments thereafter, subject to continued employment. The remaining 50% vest and become exercisable upon the occurrence of the following milestones being achieved: (i) 25% of the grant vest upon the dosing of the first patient in the first Phase 2 clinical trial of any Mustang product candidate, (ii) 25% of the grant vest upon the dosing of the first patient in the first Phase 2 clinical trial of a second Mustang product candidate, (iii) 25% of the grant vest upon Mustangs’ achievement of a fully-diluted market capitalization of $500,000,000 and (iv) 25% of the grant vest upon Mustangs’ achievement of a fully-diluted market capitalization of $1,000,000,000. The fair value of stock options granted was determined on the grant date using assumptions for risk free interest rate, the expected term, expected volatility, expected dividend yield, and a stock price of $ 5.73 September 30, 2017 Risk-free interest rate 1.81% 2.38 % Expected dividend yield - % Expected term in years 5.5 10.0 Expected volatility 77.3 % Weighted Average Remaining Weighted Contractual Average Life (in Stock Options Exercise Price years) Nonvested at December 31, 2016 - $ - - Options granted 1,241,675 $ 5.73 9.56 Options outstanding 1,241,675 5.73 9.56 Options vested and exercisable at September 30, 2017 - $ - - As of September 30, 2017, Mustang had unrecognized stock-based compensation expense related to options of $ 2.3 1.61 During the three and nine months ended September 30, 2017, stock-based compensation associated with the amortization of stock option expense was approximately $ 0.7 1.1 Certain Mustang employees and directors also have been awarded restricted stock and restricted stock units in 2017. Mustang recorded stock-based compensation expense of $ 0.2 0.2 Helocyte, Inc. For the three months ended September 30, 2017 and 2016, Helocyte re-measured its non-employee grants and recorded expense of approximately $ 20,000 50,000 For the three months ended September 30, 2017 and 2016, Helocyte recorded approximately $ 7,000 17,000 17,000 42,000 For the nine months ended September 30, 2017 and 2016, Helocyte re-measured its non-employee grants and recorded expense of approximately $ 82,000 0.1 For the nine months ended September 30, 2017 and 2016, Helocyte recorded approximately $ 25,000 42,000 Cellvation, Inc. For the three and nine months ended September 30, 2017, Cellvation recorded expenses for non-employee grants of approximately $ 2,000 7,000 For the three and nine months ended September 30, 2017, Cellvation recorded approximately $ 3,000 11,000 Capital Raises Avenue On June 26, 2017, Avenue completed an initial public offering (“IPO”) of its common stock, which resulted in the issuance of 6,325,000 825,000 6.00 34.2 3-For-1 In conjunction with the closing of the IPO, Avenue issued warrants in connection with its NSC Debt and its Convertible Notes. Mustang In September 2016, Mustang entered into a Placement Agent Agreement with NSC relating to Mustang’s offering of shares of common stock in a private placement. Pursuant to the Placement Agent Agreement, Mustang agreed to pay NSC a cash fee of 10.0 10,000 2,500 8.50 65,000 On January 31, 2017, Mustang held a sixth closing of its private placement for gross proceeds of $ 55.5 8,536,774 2,134,193 5.5 853,677 10 On March 31, 2017, Mustang closed an additional private placement with substantially similar terms as the offering described above resulting in gross proceeds of $ 0.4 64,000 16,000 42,000 10 6,400 10 On August 3, 2017, Mustang closed the final round of financing totaling gross proceeds of $ 65,000 10,000 2,500 1,000 10 Pursuant to the Founders Agreement (see Note 17), Mustang issued 215,269 2.5 1.2 As of September 30, 2017, the Company determined that the warrants still did not meet the definition of a derivative and continued to qualify for equity recognition.

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
Commitments and Contingencies	Sep. 30, 2017
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	16. Commitments and Contingencies Indemnification In accordance with its certificate of incorporation, bylaws and indemnification agreements, the Company has indemnification obligations to its officers and directors for certain events or occurrences, subject to certain limits, while they are serving at the Company’s request in such capacity. There have been no claims to date, and the Company has director and officer insurance to address such claims. Pursuant to agreements with clinical trial sites, the Company provides indemnification to such sites in certain conditions. Legal Proceedings - Fortress In the ordinary course of business, the Company and its subsidiaries may be subject to both insured and uninsured litigation. Suits and claims may be brought against the Company by customers, suppliers, partners and/or third parties (including tort claims for personal injury arising from clinical trials of the Company’s product candidates and property damage) alleging deficiencies in performance, breach of contract, etc., and seeking resulting alleged damages. On January 15, 2016, Dr. Winson Tang (“Plaintiff”) filed a Complaint against the Company in the Superior Court of the State of California, County of Los Angeles. Winson Tang v. Lindsay Rosenwald et al., In connection with settlement, above, the Company is required to deliver 200,000 0.2 Litigation and Regulatory Matters - National National and its subsidiaries are defendants or respondents in various pending and threatened arbitrations, administrative proceedings and lawsuits seeking compensatory damages. Several cases have no stated alleged damages. Claim amounts are infrequently indicative of the actual amounts National will be liable for, if any. Further, National has a history of collecting amounts awarded in these types of matters from its registered representatives that are still affiliated, as well as from those that are no longer affiliated. Many of these claimants also seek, in addition to compensatory damages, punitive or treble damages, and all seek interest, costs and fees. These matters arise in the normal course of business. National intends to vigorously defend itself in these actions, and the ultimate outcome of these matters cannot be determined at this time. Liabilities for potential losses from complaints, legal actions, government investigations and proceedings are established where National believes that it is probable that a liability has been incurred and the amount of loss can be reasonably estimated. In making these decisions, management bases its judgments on its knowledge of the situations, consultations with legal counsel and its historical experience in resolving similar matters. In many lawsuits, arbitrations and regulatory proceedings, it is not possible to determine whether a liability has been incurred or to estimate the amount of that liability until the matter is close to resolution. However, accruals are reviewed regularly and are adjusted to reflect National’s estimates of the impact of developments, rulings, advice of counsel and any other information pertinent to a particular matter. Because of the inherent difficulty in predicting the ultimate outcome of legal and regulatory actions, management cannot predict with certainty the eventual loss or range of loss related to such matters.

Related Party Transactions

Related Party Transactions	9 Months Ended
Related Party Transactions	Sep. 30, 2017
Related Party Transactions [Abstract]
Related Party Note	17. Related Party Transactions Shared Services Agreement with TGTX TGTX and the Company entered into an arrangement to share the cost of certain research and development employees. The Company’s Executive Vice Chairman, Strategic Development, is Executive Chairman and Interim Chief Executive Officer of TGTX. Under the terms of the Agreement, TGTX will reimburse the Company for the salary and benefit costs associated with these employees based upon actual hours worked on TGTX related projects. For the three months ended September 30, 2017 and 2016, the Company invoiced TGTX $ 0.2 0.3 0.8 0.6 0.1 Desk Space Agreements with TGTX and OPPM In connection with the Company’s Desk Space Agreements with TGTX and Opus Point Partners Management, LLC (“OPPM”), as of September 30, 2017, the Company had paid $ 1.8 0.1 0.6 0.3 0.1 28,000 56,000 0.1 Opus Credit Facility In September 2016, the Company and Opus Point Health Innovations Fund (“OPHIF”) entered into a Credit Facility Agreement (the “Opus Credit Facility”). Fortress’s Chairman, President and Chief Executive Officer (Lindsay A. Rosenwald) and Fortress’s Executive Vice President, Strategic Development (Michael Weiss), are Co-Portfolio Managers and Partners of OPPM, an affiliate of OPHIF. As such, all of the disinterested directors of Fortress’s board of directors approved the terms of the Opus Credit Facility and related agreements (see Note 11). For the three and nine months ended September 30, 2017 and 2016, we paid $ 0.3 0.8 2017 Subordinated Note Financing On March 17, 2017, the Company and NSC, a subsidiary of National (of which the Company owns 56.6 10 10 For the three and nine months ended September 30, 2017, NSC earned a placement agent fee of $ 0.9 2.8 716,180 3.61 4.75 Caelum Convertible Notes On July 31, 2017 Caelum through NSC, a subsidiary of National offered up to $ 10 9.9 10 0.9 10 110 the exercise price will be $75 million dollars divided by the total number of fully-diluted shares of Common Stock outstanding immediately prior to exercise of the warrant, giving effect to the assumed conversion of all options, warrants, and convertible securities of the Company Avenue IPO On June 26, 2017, Avenue completed an IPO in which NSC acted as co-manager and earned fees and commissions of approximately $ 2.3 Founders Agreements PIK Dividend as a % of fully diluted outstanding Class of Stock Fortress Company Effective Date (1) capitalization Issued Helocyte March 20, 2015 2.5 % Common Stock Avenue February 17, 2015 2.5 % Common Stock Mustang March 13, 2015 2.5 % Common Stock Checkpoint March 17, 2015 0.0 %(2) Common Stock Cellvation October 31, 2016 2.5 % Common Stock Caelum January 1, 2017 2.5 % Common Stock Cyprium March 13, 2017 2.5 % Common Stock Aevitas July 28, 2017 2.5 % Common Stock (1) - Represents the effective date of each subsidiary’s Founders Agreement. Each PIK dividend and equity fee is payable on the annual anniversary of the effective date of the original Founders Agreement. (2) - Instead of a PIK dividend, Checkpoint pays the Company an annual equity fee in shares of Checkpoint’s common stock equal to 2.5 Pursuant to the Founders’ Agreement, Caelum, in connection with each Convertible Note Closing during the three months ended September 30, 2017, issued to Fortress approximately 218,000 2.5 0.2 On June 26, 2017, pursuant to the Founders’ Agreement, Avenue, in connection with its IPO, issued to Fortress approximately 158,000 2.5 Management Services Agreements The Company has entered in Management Services Agreements (the “MSAs”) with certain of its subsidiaries as described in the Company’s Form 10-K for the year ended December 31, 2016, filed with the SEC on March 16, 2017. ($ in thousands) Annual MSA Fee Fortress Company Effective Date R&D G&A (Income)/Expense Helocyte March 20, 2015 $ 250 $ 250 $ 500 Avenue February 17, 2015 250 250 500 Mustang March 13, 2015 250 250 500 Checkpoint March 17, 2015 250 250 500 Cellvation October 31, 2016 250 250 500 Caelum January 1, 2017 250 250 500 Cyprium March 13, 2017 250 250 500 Aevitas July 28, 2017 250 250 500 Fortress (2,000) (2,000) (4,000) Consolidated (Income)/Expense $ - $ - $ - Chord Advisors, LLC In May 2015, the Company entered into a full-service consulting agreement with Chord Advisors, LLC (“Chord”) to provide advisory accounting services. Under the terms of the agreement, the Company pays Chord $ 10,000 5,000 7,500 15,000 52,000 17,000 58,000 National As of September 30, 2017, the Company owns approximately 56.6 Additionally, the Company’s Chairman, President and Chief Executive Officer and the Company’s Executive Vice Chairman, Strategic Development are both Co-Portfolio Managers and Partners of OPPM which owns approximately 4.6

Net Capital Requirements of Bro

Net Capital Requirements of Broker-Dealer Subsidiaries	9 Months Ended
Net Capital Requirements of Broker-Dealer Subsidiaries	Sep. 30, 2017
Brokers and Dealers [Abstract]
Net Capital Requirements of Broker-Dealer Subsidiaries	18. Net Capital Requirements of Broker-Dealer Subsidiaries NSC is subject to the SEC's Uniform Net Capital Rule (Rule 15c3-1) (the "Rule"), which, among other things, requires the maintenance of minimum net capital. At June 30, 2017, National Securities had net capital of $ 10.5 10.2 250,000 vFinance Investments, Inc. (vFinance Investments) is also subject to the Rule, which, among other things, requires the maintenance of minimum net capital and requires that the ratio of aggregate indebtedness to net capital, both as defined, shall not exceed 15 1 1.5 0.5 1,000,000 0.8 1 Advances, dividend payments and other equity withdrawals from the Company's broker-dealer subsidiaries are restricted by the regulations of the SEC, and other regulatory agencies. These regulatory restrictions may limit the amounts that a subsidiary may dividend or advance to the Company.

Off Balance Sheet Risk and Conc

Off Balance Sheet Risk and Concentrations of Credit Risk	9 Months Ended
Off Balance Sheet Risk and Concentrations of Credit Risk	Sep. 30, 2017
Risks and Uncertainties [Abstract]
Off Balance Sheet Risk and Concentrations of Credit Risk	19. Off Balance Sheet Risk and Concentrations of Credit Risk National is engaged in trading and providing a broad range of securities brokerage and investment services to a diverse group of retail and institutional clientele, as well as corporate finance and investment banking services to corporations and businesses. Counterparties to National’s business activities include broker-dealers and clearing organizations, banks and other financial institutions. National uses clearing brokers to process transactions and maintain customer accounts for National on a fee basis. National permits the clearing firms to extend credit to its clientele secured by cash and securities in the client’s account. National’s exposure to credit risk associated with the non-performance by its customers and counterparties in fulfilling their contractual obligations can be directly impacted by volatile or illiquid trading markets, which may impair the ability of customers and counterparties to satisfy their obligations to National. National has agreed to indemnify the clearing brokers for losses they incur while extending credit to National’s clients. It is National’s policy to review, as necessary, the credit standing of its customers and counterparties. Amounts due from customers that are considered uncollectible by the clearing broker are charged back to National by the clearing broker when such amounts become determinable. Upon notification of a charge back, such amounts, in total or in part, are then either (i) collected from the customers, (ii) charged to the broker initiating the transaction and/or (iii) charged to operations, based on the particular facts and circumstances. National maintains cash in bank deposits, which, at times, may exceed federally insured limits. National has not experienced and does not expect to experience losses on such accounts. A short sale involves the sale of a security that is not owned in the expectation of purchasing the same security (or a security exchangeable) at a later date at a lower price. A short sale involves the risk of a theoretically unlimited increase in the market price of the security that would result in a theoretically unlimited loss.

Segment Information

Segment Information	9 Months Ended
Segment Information	Sep. 30, 2017
Segment Reporting [Abstract]
Segment Information	20. Segment Information The Company operates in three reportable segments, Dermatology Product Sales, Pharmaceutical and Biotechnology Product Development and National. The accounting policies of the Company’s segments are the same as those described in Note 2. Cost of goods sold is directly related to product sales only. Revenues derived from co-promote revenue had no cost of goods sold. Dermatology Pharmaceutical ($ in thousands) Products Product Three Months Ended September 30, 2017 Sales Development National Consolidated Net Revenue $ 2,170 $ 350 $ 44,366 $ 46,886 Direct cost of goods (505) - (505) Sales and marketing costs (2,786) - (2,786) Research and development (16,190) (16,190) General and administrative (349) (11,969) (12,318) National Expenses - - (47,690) (47,690) Segment loss from operations $ (1,470) $ (27,809) $ (3,324) $ (32,603) Segment assets $ 7,362 $ 160,038 $ 77,691 $ 245,091 Pharmaceutical Dermatology Biotechnology ($ in thousands) Products Product Three Months Ended September 30, 2016 Sales Development National Consolidated Net Revenue $ 429 $ 546 $ - $ 975 Direct cost of goods (41) - - (41) Sales and marketing costs (1,244) - - (1,244) Research and development - (8,316) - (8,316) General and administrative (422) (7,198) - (7,620) Segment loss from operations $ (1,278) $ (14,968) $ - $ (16,246) Segment assets $ 2,657 $ 103,225 $ 39,539 $ 145,421 Dermatology Pharmaceutical ($ in thousands) Products Product Nine Months Ended September 30, 2017 Sales Development National Consolidated Net Revenue $ 8,309 $ 1,393 $ 132,563 $ 142,265 Direct cost of goods (1,852) - (1,852) Sales and marketing costs (7,663) - (7,663) Research and development (38,077) (38,077) General and administrative (961) (27,866) (28,827) National Expenses - - (139,219) (139,219) Segment loss from operations $ (2,167) $ (64,550) $ (6,656) $ (73,373) Segment assets $ 7,362 $ 160,038 $ 77,691 $ 245,091 Pharmaceutical Dermatology Biotechnology ($ in thousands) Products Product Nine Months Ended September 30, 2016 Sales Development National Consolidated Net Revenue $ 1,793 $ 2,072 $ - $ 3,865 Direct cost of goods (365) - - (365) Sales and marketing costs (4,212) - - (4,212) Research and development - (24,559) - (24,559) General and administrative (1,338) (19,864) - (21,202) Segment loss from operations $ (4,122) $ (42,351) $ - $ (46,473) Segment assets $ 2,657 $ 103,225 $ 39,539 $ 145,421 Significant Customers For the three months ended September 30, 2017, two of the Company’s customers each accounted for more than 10.0% of its total gross product revenue in the amount of $ 3.0 1.7 6.7 6.0 For the three months ended September 30, 2016, two of the Company’s customers accounted for more than 10.0% of its total product revenue in the amount of $ 0.2 43 0.8 0.3 0.3 At September 30, 2017, two of the Company’s customers each accounted for more than 10.0% of its total accounts receivable balance in the amount of $ 1.7 1.5 At December 31, 2016, two of the Company’s customers each accounted for more than 10.0% of its total accounts receivable balance in the amount of $ 1.1 0.5 Net Revenue from Pharmaceutical and Biotechnology Product Development represents collaboration revenue from TGTX in connection with Checkpoint, which is classified as related party revenue.

Subsequent Events

Subsequent Events	9 Months Ended
Subsequent Events	Sep. 30, 2017
Subsequent Events [Abstract]
Subsequent Events	21. Subsequent Events Mustang Manufacturing Facility On October 27, 2017, Mustang entered into a lease agreement with WCS - 377 Plantation Street, Inc., a Massachusetts nonprofit corporation ("Landlord"). Pursuant to the terms of the lease agreement, Mustang agreed to lease 27,043 0.6 3.6 3.5 The terms of the lease also require that Mustang post an initial security deposit of $ 0.8 0.5 0.3 1.3 1.0 0.3 The facility is expected to be operational for the production of personalized CAR T therapies in 2018. Fortress Perpetual Preferred Offering On November 6, 2017, the Company priced an underwritten public offering of one million shares of our 9.375 25.00 25 150,000

Summary of Significant Accoun28

Summary of Significant Accounting Policies (Policies)	9 Months Ended
Summary of Significant Accounting Policies (Policies)	Sep. 30, 2017
Accounting Policies [Abstract]
Basis of Presentation and Principles of Consolidation	Basis of Presentation and Principles of Consolidation The accompanying unaudited interim condensed consolidated financial statements have been prepared in accordance with generally accepted accounting principles in the United States of America (“GAAP”) for interim financial information and the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by GAAP for complete financial statements. In the opinion of management, the unaudited interim condensed consolidated financial statements reflect all adjustments, which include only normal recurring adjustments necessary for the fair statement of the balances and results for the periods presented. Certain information and footnote disclosures normally included in the Company’s annual financial statements prepared in accordance with GAAP have been condensed or omitted. These condensed consolidated financial statement results are not necessarily indicative of results to be expected for the full fiscal year or any future period. The unaudited condensed consolidated financial statements and related disclosures have been prepared with the presumption that users of the unaudited condensed consolidated financial statements have read or have access to the audited consolidated financial statements for the preceding fiscal year for each of the Company, Avenue, Checkpoint, Mustang and National. Accordingly, these unaudited condensed consolidated financial statements should be read in conjunction with the Company’s Form 10-K, which was filed with the United States Securities and Exchange Commission (“SEC”) on March 16, 2017, from which the Company derived the balance sheet data at December 31, 2016, as well as National’s Form 10-K, filed with SEC on December 29, 2016 and their Form 10-Q, filed with the SEC on August 14, 2017, Checkpoint’s Forms 10-K and 10-K/A, filed with the SEC on March 17, 2017 and March 21, 2017, respectively, Mustang’s Form 10-K, filed with the SEC on March 31, 2017, and Avenue’s Form 10-12G/A, filed with the SEC on March 27, 2017. The Company’s unaudited condensed consolidated financial statements include the accounts of the Company and its subsidiaries: NHLD, Innmune Limited, Coronado SO, Cyprium, Escala, JMC, CB Securities Corporation, Avenue, Checkpoint, Mustang, Helocyte, Cellvation, Caelum and Aevitas. All intercompany balances and transactions have been eliminated. The National assets acquired and liabilities assumed and revenues and expenses are reported on a one quarter lag. Therefore, the National assets acquired and liabilities assumed included in these consolidated financial statements as of September 30, 2017 are actually the assets and liabilities as of June 30, 2017 and the revenues and expenses included in these consolidated financial statements for the quarter ending September 30, 2017 are actually the revenues and expenses for the quarter ending June 30, 2017. The preparation of the Company’s unaudited condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the unaudited condensed consolidated financial statements and the reported amounts of expenses during the reporting period.
Use of Estimates	Use of Estimates The Company’s unaudited condensed consolidated financial statements include certain amounts that are based on management’s best estimates and judgments. The Company’s significant estimates include, but are not limited to, useful lives assigned to long-lived and intangible assets, fair value measurements, stock-based compensation, common stock issued to acquire licenses, investments, accrued expenses, derivative warrant liabilities, provisions for income taxes and contingencies. Due to the uncertainty inherent in such estimates, actual results may differ from these estimates.
Significant Accounting Policies	Significant Accounting Policies There have been no material changes to the Company’s significant accounting policies previously disclosed in the Company’s Form 10-K filed with the SEC on March 16, 2017, with the exception of the policies listed below.
Cash and Cash Equivalents	Cash and Cash Equivalents The Company considers all short-term investments with an original maturity of three months or less when purchased to be cash equivalents. Cash and cash equivalents at September 30, 2017 and at December 31, 2016 consisted of cash, money market funds and certificates of deposit in institutions in the United States. Balances at certain institutions have exceeded Federal Deposit Insurance Corporation insured limits and U.S. government agency securities.
Investments at Fair Value	Short-term Investments Held to Maturity The company classifies its certificates of deposit as cash and cash equivalents or held to maturity in accordance with the Financial Accounting Standards Board ("FASB") Accounting Standards Codification (“ASC”) 320, Investments Debt and Equity Securities At September 30, 2017, the Company had approximately $ 60.1 250,000 16.0 44.1
Recently Issued Accounting Standards	Recently Adopted Accounting Pronouncements In March 2016, the FASB issued Accounting Standards Update ("ASU") 2016-09, Compensation-Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting In January 2017, the FASB issued ASU 2017-04, Intangibles - Goodwill and Other (Topic 350): Simplifying the Accounting for Goodwill Impairment In January 2017, the FASB issued ASU 2017-01, Business Combinations (Topic 805): Clarifying the Definition of a Business Recent Accounting Pronouncements In May 2014, the FASB issued ASU 2014-09, Revenue from Contracts with Customers (Topic 606) Revenue from Contracts with Customers (Topic 606): Identifying Performance Obligations and Licensing In January 2016, the FASB issued ASU 2016-01, Financial Instruments - Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Liabilities In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842). In June 2016, the FASB issued ASU 2016-13, Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments In August 2016, the FASB issued ASU 2016-15, Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments, Statement of Cash Flows (Topic 230): Restricted Cash In May 2017, the FASB issued ASU 2017-09, Compensation-Stock Compensation (Topic 718): Scope of Modification Accounting In July 2017, the FASB issued ASU 2017-11, Earnings Per Share (Topic 260), Distinguishing Liabilities from Equity (Topic 480) and Derivatives and Hedging (Topic 815): I. Accounting for Certain Financial Instruments with Down Round Features; II. Replacement of the Indefinite Deferral for Mandatorily Redeemable Financial Instruments of Certain Nonpublic Entities and Certain Mandatorily Redeemable Noncontrolling Interests with a Scope Exception

National Holdings Corporation29

National Holdings Corporation Acquisition - Intangible Assets (Tables)	9 Months Ended
	Sep. 30, 2017
Business Combinations [Abstract]
Schedule of Acquired Finite-Lived Intangible Assets by Major Class	Amortization is calculated using the straight-line and accelerated methods over the following estimated useful lives: Useful life Trademark 10 years Customer lists 10 years
Schedule of Finite-Lived Intangible Assets	The carrying amount related to acquired intangible assets as of September 30, 2017 are as follows ($ in thousands): Intangible assets at December 31, 2016 $ 15,991 Amortization expense (1,235) Intangible assets at September 30, 2017 $ 14,756
Schedule of Finite-Lived Intangible Assets, Future Amortization Expense	The future amortization of these intangible assets is as follows ($ in thousands): Total Three Months Ended December 31, 2017 $ 415 Year Ended December 31, 2018 1,649 Year Ended December 31, 2019 1,649 Year Ended December 31, 2020 1,654 Year Ended December 31, 2021 1,649 Thereafter 7,740 Total $ 14,756

Property and Equipment (Tables)

Property and Equipment (Tables)	9 Months Ended
Property and Equipment (Tables)	Sep. 30, 2017
Property, Plant and Equipment [Line Items]
Components of Property and Equipment	Fortress's property and equipment, exclusive of National's property and equipment, consisted of the following ($ in thousands): Estimated Useful September 30, December 31, Lives (in years) 2017 2016 Computer equipment 3 $ 523 $ 440 Furniture and fixtures 5 1,002 821 Leasehold improvements Various 5,351 5,396 Construction in process (1) N/A 139 - Total property and equipment 7,015 6,657 Less: accumulated depreciation (986) (445) Property and equipment, net $ 6,029 $ 6,212 (1) In connection with Mustang’s manufacturing facility, Mustang incurred $ 0.1
National Holdings Corporation [Member]
Property, Plant and Equipment [Line Items]
Components of Property and Equipment	National's property and equipment as of June 30, 2017 consisted of the following ($ in thousands): Estimated Useful June 30, Lives (in years) 2017 Equipment 5 $ 1,305 Furniture and fixtures 5 240 Leasehold improvements Lesser of useful life or term of lease 685 Capital leases (primarily composed of computer equipment) 5 276 Total property and equipment 2,506 Less: accumulated depreciation (314) Property and equipment, net $ 2,192

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	9 Months Ended
Fair Value Measurements (Tables)	Sep. 30, 2017
Fair Value for Derivative Contingently Issuable Warrant Liabilities	Avenue’s Contingently Issuable ($ in thousands) Warrants Beginning balance at January 1, 2017 $ 302 Conversion into common shares (750) Change in fair value 448 Ending balance at September 30, 2017 $ -
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis	The following tables classify the fair value hierarchy of Fortress's financial instruments, exclusive of National's financial instruments, measured at fair value as of September 30, 2017 and December 31, 2016: Fair Value Measurement as of September 30, 2017 ($ in thousands) Level 1 Level 2 Level 3 Total Assets Long-term investments, at fair value $ - $ - $ 923 $ 923 Total $ - $ - $ 923 $ 923 Liabilities Warrant liabilities $ - $ - $ 313 $ 313 Caelum Convertible Note, at fair value - - 9,928 9,928 Helocyte Convertible Note, at fair value - - 4,733 4,733 Total $ - $ - $ 14,974 $ 14,974 Fair Value Measurement as of December 31, 2016 ($ in thousands) Level 1 Level 2 Level 3 Total Assets Long-term investments, at fair value $ - $ - $ 1,414 $ 1,414 Total $ - $ - $ 1,414 $ 1,414 Liabilities Contingently Issuable Warrants $ - $ - $ 302 $ 302 Warrant liabilities - - 179 179 Helocyte Convertible Note, at fair value - - 4,487 4,487 Avenue Convertible Note, at fair value - - 200 200 Total $ - $ - $ 5,168 $ 5,168
Schedule of changes in fair value of financial instruments	The table below provides a roll-forward of the changes in fair value of Level 3 financial instruments for the nine months ended September 30, 2017: Convertible Note, at fair value Contingently Investment in Investment in Issuable Warrant ($ in thousands) Origo laser device Helocyte Avenue Caelum Warrants liabilities Total Balance at December 31, 2016 $ 1,164 $ 250 $ 4,487 $ 200 $ - $ 14,661 $ 179 $ 20,941 Additions during the period - - - - 9,914 - 225 10,139 Conversion into common shares - - - (299) - (750) (15) (1,064) Issuance of warrants - - - - - (8,190) 8,190 - Loss on write off investment - (250) - - - - - (250) Change in fair value of investments (241) - - - - - - (241) Change in fair value of convertible notes - - 246 99 14 - - 359 Change in fair value of derivative liabilities - - - - - (5,079) (76) (5,155) Balance at September 30, 2017 $ 923 $ - $ 4,733 $ - $ 9,928 $ 642 $ 8,503 $ 24,729
Warrants Issuable [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques	June 30, 2017 Dividend yield - % Expected volatility 91 % Risk-free interest rate 1.890 % Life (in years) 4.20
Fair Value for Derivative Contingently Issuable Warrant Liabilities	National’s ($ in thousands) Warrants Beginning balance at December 31, 2016 $ 14,359 Change in fair value of derivative liability (5,527) Ending balance at June 30, 2017 $ 8,832
Avenue [Member] \| Warrant [Member]
Fair Value for Derivative Contingently Issuable Warrant Liabilities	Avenue’s Warrant ($ in thousands) Liability Beginning balance at January 1, 2017 $ 12 Conversion into common shares (15) Change in fair value 3 Ending balance at September 30, 2017 $ -
Helocyte [Member] \| Convertible Debt [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques	September 30, 2017 Risk-free interest rate 1.199% 1.336 % Expected dividend yield - % Expected term in years 0.50 1.16 Expected volatility 59.5 %
Fair Value for Derivative Contingently Issuable Warrant Liabilities	($ in thousands) Helocyte Beginning balance at January 1, 2017 $ 4,487 Change in fair value of convertible notes 246 Ending balance at September 30, 2017 $ 4,733
Helocyte [Member] \| Warrant [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques	September 30, 2017 Risk-free interest rate 1.733% 1.795 % Expected dividend yield - % Expected term in years 3.75 4.17 Expected volatility 70.0 % Strike price $ 0.44
Caelum Convertible Notes [Member] \| Convertible Debt [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques	September 30, 2017 Risk-free interest rate 1.246% 1.463 % Expected dividend yield - % Expected term in years 0.71 1.95 Expected volatility 70.0 %
Fair Value for Derivative Contingently Issuable Warrant Liabilities	Caelum Convertible Note, at fair ($ in thousands) value Beginning balance at January 1, 2017 $ - Additions 9,914 Change in fair value of convertible notes 14 Ending balance at September 30, 2017 $ 9,928
Caelum Warrant Liabilities [Member] \| Warrant [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques	September 30, 2017 Risk-free interest rate 1.895% 1.914 % Expected dividend yield - % Expected term in years 4.84 4.96 Expected volatility 70.0 % Strike price $ 1.43
Fair Value for Derivative Contingently Issuable Warrant Liabilities	($ in thousands) Fair Value of Beginning balance at January 1, 2017 $ - Change in fair value of derivative liabilities 225 Ending balance at September 30, 2017 $ 225
Avenue Convertible Notes [Member] \| Convertible Debt [Member]
Fair Value for Derivative Contingently Issuable Warrant Liabilities	Avenue Convertible Note, at fair ($ in thousands) value Beginning balance at January 1, 2017 $ 200 Conversion into common shares (299) Change in fair value of convertible notes 99 Ending balance at September 30, 2017 $ -
National Holdings Corporation [Member]
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis	The following table shows the fair values hierarchy of National's financial instruments measured at fair value on a recurring basis on the Condensed Consolidated Balance Sheets as of June 30, 2017: Fair Value Measurement as of June 30, 2017 ($ in thousands) Level 1 Level 2 Level 3 Total Assets National Securities owned, at fair value Corporate stocks $ 70 $ - $ - $ 70 Municipal bonds 816 517 - 1,333 Restricted stock - 192 - 192 Total $ 886 $ 709 $ - $ 1,595 Liabilities National Securities sold, but not yet purchased at fair value Contingent consideration $ - $ - $ 637 $ 637 Warrants - National - 8,832 8,832 Total $ - $ - $ 9,469 $ 9,469

Licenses Acquired (Tables)

Licenses Acquired (Tables)	9 Months Ended
Licenses Acquired (Tables)	Sep. 30, 2017
Research and Development [Abstract]
Research and Development Arrangement, Contract to Perform for Others	As such, for the three and nine months ended September 30, 2017 and 2016, respectively, the purchase price of licenses acquired was classified as research and development-licenses acquired in the Condensed Consolidated Statements of Operations, as reflected in the table below: For the Three Months Ended September 30, For the Nine Months Ended September 30, ($ in thousands) 2017 2016 2017 2016 Fortress $ - $ - $ 300 $ - Fortress Companies: Checkpoint - 1,000 400 3,060 Helocyte - - - 83 Mustang 300 - 2,375 - Caelum - - 219 - Cyprium - - 100 - Total $ 300 $ 1,000 $ 3,394 $ 3,143

Debt and Interest (Tables)

Debt and Interest (Tables)	9 Months Ended
Debt and Interest (Tables)	Sep. 30, 2017
Debt Disclosure [Abstract]
Schedule Of Interest Expenses	Total debt consists of the following as of September 30, 2017 and December 31, 2016: September 30, December 31, ($ in thousands) 2017 2016 Interest rate Maturity IDB Note $ 14,929 $ 14,929 2.25 % Feb - 2018 NSC Note - 3,608 8.00 % Sep - 2018 2017 Subordinated Note Financing 3,254 - 8.00 % March - 2020 2017 Subordinated Note Financing 13,893 - 8.00 % May - 2020 2017 Subordinated Note Financing 1,820 - 8.00 % June - 2020 2017 Subordinated Note Financing 3,017 - 8.00 % August - 2020 2017 Subordinated Note Financing 6,371 - 8.00 % September - 2020 Opus Credit Facility 9,500 7,000 12.00 % Sep - 2018 Helocyte Convertible Note, at fair value 1,084 1,031 5.00% - 8.00 % December 2017 Helocyte Convertible Note, at fair value 2,164 2,051 5.00% - 8.00 % March - 2018 Helocyte Convertible Note, at fair value 1,049 991 5.00% - 8.00 % April - 2018 Helocyte Convertible Note, at fair value 436 414 5.00% - 8.00 % May - 2018 Avenue Convertible Note, at fair value - 200 5.00% - 8.00 % June - 2018 Caelum Convertible Note, at fair value 1,004 - 8.00 % January - 2019 Caelum Convertible Note, at fair value 6,810 - 8.00 % February -2019 Caelum Convertible Note, at fair value 2,114 - 8.00 % June - 2019 Total notes payable 67,445 30,224 Less: Discount on notes payable 3,827 2,009 Total notes payable $ 63,618 $ 28,215
Schedule Of Interest Expenses For Debt Arrangements	For the Three Months Ended For the Nine Months Ended September 30, September 30, ($ in thousands) 2017 2016 2017 2016 IDB Note Interest $ 85 $ 84 $ 254 $ 243 Amortization of fees - - - 1 Total IDB Note 85 84 254 244 NSC Debt Interest (8) 145 147 456 Amortization of fees 127 135 200 557 Total NSC Debt 119 280 347 1,013 2017 Subordinated Note Interest 755 - 1,161 - Amortization of fees 208 - 383 - Total 2017 Subordinated Note 963 - 1,544 - Opus Credit Facility Interest 287 26 798 26 Amortization of fees 282 28 733 28 Total Opus Note 569 54 1,531 54 LOC Fees Interest 7 3 22 10 Total LOC 7 3 22 10 Helocyte Convertible Note Interest 64 26 175 26 Financing fee - 242 1 491 Total Helocyte Convertible Note 64 268 176 517 Avenue Convertible Note Interest - - 5 - Financing fee - - 3 - Total Avenue Convertible Note - - 8 - Caelum Convertible Note Interest 68 - 68 - Financing fee 1,317 - 1,317 - Total Caelum Convertible Note 1,385 - 1,385 - Falk CSR Interest 26 - 26 - Total Falk CSR 26 - 26 - D&O Insurance Interest 2 - 5 - Total D&O Insurance 2 - 5 - Total Interest Expense and Financing Fee $ 3,220 $ 689 $ 5,298 $ 1,838

Accrued Expenses and Other Lo34

Accrued Expenses and Other Long-Term Liabilities (Tables)	9 Months Ended
Accrued Expenses and Other Long-Term Liabilities (Tables)	Sep. 30, 2017
Components of Accrued Expenses and Other Long-Term Liabilities	September 30, December 31, ($ in thousands) 2017 2016 Accrued expenses: Professional fees $ 1,297 $ 1,253 Salaries, bonuses and related benefits 4,178 2,846 Accrued Severance - 53 Accrued Legal Settlement (1) 2,212 - Ovamed manufacturing rights - short term component - 900 Research and development 3,311 394 Dr. Falk Pharma milestone 2,950 2,634 Other 2,703 2,002 Total accrued expenses $ 16,651 $ 10,082 Other long-term liabilities: Deferred rent and long-term lease abandonment charge 4,736 5,014 Total other long-term liabilities $ 4,736 $ 5,014 (1) In connection with a legal settlement (see Note 16), the Company is required to deliver 200,000 Contingencies, 2.0
National Holdings Corporation [Member]
Components of Accrued Expenses and Other Long-Term Liabilities	June 30, 2017 Legal $ 836 Audit 148 Telecommunications 196 Data Services 450 Regulatory 661 Settlements 2,633 Deferred rent 177 Contingent consideration payable 636 Income taxes payable 927 Other 1,844 Total $ 8,508

Non-Controlling Interests (Tabl

Non-Controlling Interests (Tables)	9 Months Ended
Non-Controlling Interests (Tables)	Sep. 30, 2017
Noncontrolling Interest [Abstract]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net	Non-controlling interests in consolidated entities, as recorded on the Condensed Consolidated Balance Sheets are as follows: As of September 30, 2017 ($ in thousands) Avenue Coronado SO Mustang Checkpoint JMC Helocyte Cellvation Caelum Aevitas National Total NCI equity share $ 17,306 $ (236) $ 47,840 $ 22,368 $ (535) $ (1,848) $ (239) $ 7 $ (9) $ 17,022 $ 101,676 Net loss attributed to non-controlling interests (1,329) (22) (8,268) (10,144) (150) (975) (60) (1,086) (166) 4,845 (17,355) Non-controlling interests in consolidated entities $ 15,977 $ (258) $ 39,572 $ 12,224 $ (685) $ (2,823) $ (299) $ (1,079) $ (175) $ 21,867 $ 84,321 As of December 31, 2016 ($ in thousands) Avenue Coronado SO Mustang Checkpoint JMC Helocyte Cellvation National Total NCI equity share $ (494) $ (217) $ 12,376 $ 32,160 $ (192) $ (612) $ 4 $ 17,643 $ 60,668 Net loss attributed to non-controlling interests (349) (19) (1,805) (11,733) (355) (1,155) (158) (621) (16,195) Non-controlling interests in consolidated entities $ (843) $ (236) $ 10,571 $ 20,427 $ (547) $ (1,767) $ (154) $ 17,022 $ 44,473
Components Of Non-Controlling Interests In Loss Of Consolidated Entities	For the three months ended September 30, 2017 ($ in thousands) Avenue (2) Coronado Mustang (2) Checkpoint JMC Helocyte Cellvation Caelum Aevitas National Total Non-controlling interests in loss of consolidated entities $ (1,015) $ (15) $ (3,241) $ (3,437) $ (103) $ (376) $ 24 $ (835) $ (166) $ (27) $ (9,191) Non-controlling ownership 66.1 % 13.0 % 60.8 % 61.9 % 6.9 % 20.0 % 22.0 % 25.2 % 25.3 % 43.4 % For the nine months ended September 30, 2017 ($ in thousands) Avenue Coronado Mustang Checkpoint JMC Helocyte Cellvation Caelum Aevitas National Total Non-controlling interests in loss of consolidated entities $ (1,329) $ (22) $ (8,268) $ (10,144) $ (150) $ (975) $ (60) $ (1,086) $ (166) $ 4,845 $ (16,011) Non-controlling ownership 28.9 % 13.0 % 58.7 % 61.9 % 6.9 % 20.0 % 22.0 % 25.2 % 25.3 % 43.4 % For the three months ended September 30, 2016 ($ in thousands) Avenue Coronado SO Mustang Checkpoint JMC Helocyte Total Non-controlling interests in loss of consolidated entities $ (47) $ (4) $ (204) $ (3,254) $ (104) $ (362) $ (3,975) Non-controlling ownership (3) 10.5 % 13.0 % 23.9 % 62.7 % 8.1 % 20.6 % For the nine months ended September 30, 2016 ($ in thousands) Avenue Coronado SO Mustang Checkpoint JMC Helocyte Total Non-controlling interests in loss of consolidated entities $ (231) $ (14) $ (363) $ (10,767) $ (333) $ (616) $ (12,324) Non-controlling ownership (3) 10.5 % 13.0 % 10.0 % 63.5 %(1) 8.1 % 20.6 % (1) - Checkpoint is consolidated with Fortress’s operations because Fortress maintains voting control through its ownership of Checkpoint’s Class A common shares which provide for super-majority voting rights. (2) - Mustang and Avenue are consolidated with Fortress’s operations because Fortress maintains voting control through its ownership of Mustang’s and Avenue’s Class A preferred shares which provide super-majority voting rights. (3) - Represents a weighted average of ownership during the periods presented.

Net Loss per Common Share (Tabl

Net Loss per Common Share (Tables)	9 Months Ended
Net Loss per Common Share (Tables)	Sep. 30, 2017
Earnings Per Share [Abstract]
Computations of Diluted Weighted Average Shares Outstanding	The following shares of potentially dilutive securities have been excluded from the computations of diluted weighted average shares outstanding, as the effect of including such securities would be anti-dilutive at the end of the nine months ended September 30, 2017 and 2016: Nine Months Ended September 30, 2017 2016 Warrants to purchase Common Stock 678,072 480,559 Opus warrants to purchase Common Stock 206,593 1,700,000 Options to purchase Common Stock 1,095,905 1,769,426 Unvested Restricted Stock 9,848,505 8,763,797 Unvested Restricted Stock Units 1,234,555 1,054,091 Total 13,063,630 13,767,873

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	9 Months Ended
Stockholders' Equity (Tables)	Sep. 30, 2017
Schedule of Share-based Compensation, Activity	The following table summarizes the stock-based compensation expense from stock option awards, restricted common stock awards, employee stock purchase programs and warrants granted by Fortress for the three and nine months ended September 30, 2017 and 2016: Three Months Ended Nine Months Ended September 30, September 30, ($ in thousands) 2017 2016 2017 2016 Employee awards $ 1,650 $ 1,937 $ 5,170 $ 5,490 Non-employee awards 24 3 60 9 Fortress Companies 2,510 (1) 963 (2) 6,506 (3) 3,293 (4) Total stock-based compensation expense $ 4,183 $ 2,903 $ 11,736 $ 8,792 (1) Consists of approximately $ 0.2 0.9 0.8 0.4 62,000 27,000 5,000 (2) 5,000 0.8 130,000 67,000 (3) Consists of approximately $ 0.3 4.3 1.2 0.4 0.2 0.1 19,000 (4) Consists of approximately $ 23,000 2.7 458,000 160,000
Share Based Compensation Arrangement By Share Based Payment Award Options Vested And Expected To Vest Outstanding And Exercisable	The following table summarizes Fortress stock option activities excluding activity related to Fortress Companies: Weighted average Total weighted remaining Weighted average average intrinsic contractual life Number of shares exercise price value (years) Options vested and expected to vest at December 31, 2016 1,130,501 $ 3.73 $ 602,451 4.93 Exercised (20,000) 1.37 61,000 - Options vested and expected to vest at September 30, 2017 1,100,501 $ 3.78 $ 1,620,046 4.21 Options vested and exercisable 1,085,501 $ 3.75 $ 1,620,046 4.18
Nonvested Restricted Stock Shares Activity	The following table summarizes Fortress’s restricted stock and restricted stock unit award activity, excluding activity related to Fortress Companies (which is discussed below): Weighted average Number of shares grant price Unvested balance at December 31, 2016 10,094,095 $ 2.49 Restricted stock granted 1,325,396 2.70 Restricted stock vested (213,333) 2.75 Restricted stock units granted 930,000 4.31 Restricted stock units forfeited (15,000) 2.98 Restricted stock units vested (214,625) 3.44 Unvested balance at September 30, 2017 11,906,533 $ 2.63
Schedule of Warrant Activities	The following table summarizes Fortress warrant activities, excluding activities related to Fortress Companies: Weighted average Total weighted remaining Weighted average average intrinsic contractual life Number of shares exercise price value (years) Outstanding as of December 31, 2016 2,263,453 $ 3.62 $ 79,800 4.74 Granted 816,180 1.33 329,954 4.87 Forfeited (230,444) 8.39 - - Outstanding as of September 30, 2017 2,849,189 $ 2.57 $ 3,358,161 4.69 Exercisable as of September 30, 2017 869,189 $ 3.96 $ 546,561 4.30
Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions	The fair value of options granted in 2017 was estimated using the following assumptions: September 30, 2017 Risk-free interest rate 1.88% - 2.22 % Expected dividend yield - % Expected term in years 5.0 7.0 Expected volatility 107 %
Mustang Bio, Inc [Member]
Share Based Compensation Arrangement By Share Based Payment Award Options Vested And Expected To Vest Outstanding And Exercisable	The following table summarizes stock option activities for the nine months ended September 30, 2017: Weighted Average Remaining Weighted Contractual Average Life (in Stock Options Exercise Price years) Nonvested at December 31, 2016 - $ - - Options granted 1,241,675 $ 5.73 9.56 Options outstanding 1,241,675 5.73 9.56 Options vested and exercisable at September 30, 2017 - $ - -
Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions	The value associated with the market award vesting was determined utilizing a Monte Carlo simulation valuation methodology and the following assumptions: September 30, 2017 Risk-free interest rate 1.81% 2.38 % Expected dividend yield - % Expected term in years 5.5 10.0 Expected volatility 77.3 %

Related Party Transactions (Tab

Related Party Transactions (Tables)	9 Months Ended
Related Party Transactions (Tables)	Sep. 30, 2017
Related Party Transactions [Abstract]
Schedule of Effective Date and Equity Fee Payable	PIK Dividend as a % of fully diluted outstanding Class of Stock Fortress Company Effective Date (1) capitalization Issued Helocyte March 20, 2015 2.5 % Common Stock Avenue February 17, 2015 2.5 % Common Stock Mustang March 13, 2015 2.5 % Common Stock Checkpoint March 17, 2015 0.0 %(2) Common Stock Cellvation October 31, 2016 2.5 % Common Stock Caelum January 1, 2017 2.5 % Common Stock Cyprium March 13, 2017 2.5 % Common Stock Aevitas July 28, 2017 2.5 % Common Stock (1) - Represents the effective date of each subsidiary’s Founders Agreement. Each PIK dividend and equity fee is payable on the annual anniversary of the effective date of the original Founders Agreement. (2) - Instead of a PIK dividend, Checkpoint pays the Company an annual equity fee in shares of Checkpoint’s common stock equal to 2.5
Schedule of The Effective Date and Annual Management Services agreement Fee Income Expense	The following table summarizes, by subsidiary, the effective date of the MSA and the annual consulting fee payable by the subsidiary to the Company in quarterly installments: ($ in thousands) Annual MSA Fee Fortress Company Effective Date R&D G&A (Income)/Expense Helocyte March 20, 2015 $ 250 $ 250 $ 500 Avenue February 17, 2015 250 250 500 Mustang March 13, 2015 250 250 500 Checkpoint March 17, 2015 250 250 500 Cellvation October 31, 2016 250 250 500 Caelum January 1, 2017 250 250 500 Cyprium March 13, 2017 250 250 500 Aevitas July 28, 2017 250 250 500 Fortress (2,000) (2,000) (4,000) Consolidated (Income)/Expense $ - $ - $ -

Segment Information (Tables)

Segment Information (Tables)	9 Months Ended
Segment Information (Tables)	Sep. 30, 2017
Segment Reporting [Abstract]
Schedule of Segment Reporting Information, by Segment	The following tables summarize, for the periods indicated, operating results by reportable segment: Cost of goods sold is directly related to product sales only. Revenues derived from co-promote revenue had no cost of goods sold. Dermatology Pharmaceutical ($ in thousands) Products Product Three Months Ended September 30, 2017 Sales Development National Consolidated Net Revenue $ 2,170 $ 350 $ 44,366 $ 46,886 Direct cost of goods (505) - (505) Sales and marketing costs (2,786) - (2,786) Research and development (16,190) (16,190) General and administrative (349) (11,969) (12,318) National Expenses - - (47,690) (47,690) Segment loss from operations $ (1,470) $ (27,809) $ (3,324) $ (32,603) Segment assets $ 7,362 $ 160,038 $ 77,691 $ 245,091 Pharmaceutical Dermatology Biotechnology ($ in thousands) Products Product Three Months Ended September 30, 2016 Sales Development National Consolidated Net Revenue $ 429 $ 546 $ - $ 975 Direct cost of goods (41) - - (41) Sales and marketing costs (1,244) - - (1,244) Research and development - (8,316) - (8,316) General and administrative (422) (7,198) - (7,620) Segment loss from operations $ (1,278) $ (14,968) $ - $ (16,246) Segment assets $ 2,657 $ 103,225 $ 39,539 $ 145,421 Dermatology Pharmaceutical ($ in thousands) Products Product Nine Months Ended September 30, 2017 Sales Development National Consolidated Net Revenue $ 8,309 $ 1,393 $ 132,563 $ 142,265 Direct cost of goods (1,852) - (1,852) Sales and marketing costs (7,663) - (7,663) Research and development (38,077) (38,077) General and administrative (961) (27,866) (28,827) National Expenses - - (139,219) (139,219) Segment loss from operations $ (2,167) $ (64,550) $ (6,656) $ (73,373) Segment assets $ 7,362 $ 160,038 $ 77,691 $ 245,091 Pharmaceutical Dermatology Biotechnology ($ in thousands) Products Product Nine Months Ended September 30, 2016 Sales Development National Consolidated Net Revenue $ 1,793 $ 2,072 $ - $ 3,865 Direct cost of goods (365) - - (365) Sales and marketing costs (4,212) - - (4,212) Research and development - (24,559) - (24,559) General and administrative (1,338) (19,864) - (21,202) Segment loss from operations $ (4,122) $ (42,351) $ - $ (46,473) Segment assets $ 2,657 $ 103,225 $ 39,539 $ 145,421

Summary of Significant Accoun40

Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($)	9 Months Ended
	Sep. 30, 2017		Sep. 30, 2016
Accounting Policies [Line Items]
Payments to Acquire Short-term Investments	$ 44,088,000	[1]	$ 0
Short Term Investment Maximum Amount Per Institution	250,000
Held-to-maturity Securities [Member]
Accounting Policies [Line Items]
Time Deposits, at Carrying Value	44,100,000
Cash and Cash Equivalents [Member]
Accounting Policies [Line Items]
Time Deposits, at Carrying Value	$ 16,000,000

[1]	In connection with Mustang’s manufacturing facility, Mustang incurred $0.1 million related to the design of the facility as of September 30, 2017.

National Holdings Corporation41

National Holdings Corporation Acquisition - Intangible Assets - Amortization is calculated using the straight-line method over the estimated useful lives (Detail)	9 Months Ended
	Sep. 30, 2017
Trademark [Member]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	10 years
Customer Lists [Member]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	10 years

National Holdings Corporation42

National Holdings Corporation Acquisition - Intangible Assets - gross carrying amounts related to acquired intangible assets (Detail) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016
Intangible assets at December 31, 2016	$ 15,991
Amortization expense	(1,235)	$ 0
Intangible assets at September 30, 2017	$ 14,756

National Holdings Corporation43

National Holdings Corporation Acquisition - Intangible Assets - future amortization of these intangible assets (Detail) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Total	$ 15,983	$ 17,408
National Holdings Corporation [Member]
Three Months Ended December 31, 2017	415
Year Ended December 31, 2018	1,649
Year Ended December 31, 2019	1,649
Year Ended December 31, 2020	1,654
Year Ended December 31, 2021	1,649
Thereafter	7,740
Total	$ 14,756

National Holdings Corporation44

National Holdings Corporation Acquisition - Intangible Assets - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	Sep. 30, 2017	Mar. 17, 2017	Dec. 31, 2016	Sep. 09, 2016
Common Stock Par Or Stated Value Per Share	$ 0.001		$ 0.001
Goodwill	$ 18,645		$ 18,645
National Holdings Corporation [Member]
Business Acquisition, Percentage of Voting Interests Acquired	56.60%	56.60%		56.60%
Business Acquisition, Share Price				$ 3.25
Common Stock Par Or Stated Value Per Share				$ 0.02

Broker-Dealers and Clearing O45

Broker-Dealers and Clearing Organizations, Other Receivables and Prepaid Expenses and Other Current Liabilities - Additional Information (Detail) - USD ($) $ in Thousands	Sep. 30, 2017	Jun. 30, 2017	Dec. 31, 2016
Brokers And Dealers [Line Items]
Receivables from Brokers-Dealers and Clearing Organizations	$ 8,282		$ 3,357
Broker -Dealers And clearing Organisation [Member]
Brokers And Dealers [Line Items]
Receivables from Brokers-Dealers and Clearing Organizations		$ 2,800
Allowance for Doubtful Accounts Receivable		500
Broker -Dealers And clearing Organisation [Member] \| Other Receivable [Member]
Brokers And Dealers [Line Items]
Accounts Receivable, Net		$ 6,000

Forgivable Loans Receivable - A

Forgivable Loans Receivable - Additional Information (Detail)	Sep. 30, 2017
Forgivable Loan Receivable [Member]
Debt Instrument, Interest Rate, Stated Percentage	9.00%

Property and Equipment - Compon

Property and Equipment - Components of Property and Equipment (Detail) - USD ($) $ in Thousands		9 Months Ended
		Sep. 30, 2017	Dec. 31, 2016
Property, Plant and Equipment [Line Items]
Property and equipment, net		$ 8,221	$ 7,376
Fortress Biotech Inc [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment		7,015	6,657
Less: accumulated depreciation		(986)	(445)
Property and equipment, net		6,029	6,212
Computer Equipment [Member] \| Fortress Biotech Inc [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment		$ 523	440
Useful Life (Years)		3 years
Furniture and Fixtures [Member] \| Fortress Biotech Inc [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment		$ 1,002	821
Useful Life (Years)		5 years
Leasehold Improvements [Member] \| Fortress Biotech Inc [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment		$ 5,351	5,396
Property, Plant and Equipment, Estimated Useful Lives		Various
Construction in progress [Member] \| Fortress Biotech Inc [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment	[1]	$ 139	$ 0

[1]	In connection with Mustang’s manufacturing facility, Mustang incurred $0.1 million related to the design of the facility as of September 30, 2017.

Property and Equipment - Schedu

Property and Equipment - Schedule Of Interest Expenses For Debt Arrangements (Detail) - USD ($) $ in Thousands	3 Months Ended
	Jun. 30, 2017	Sep. 30, 2017	Dec. 31, 2016
Property, Plant and Equipment [Line Items]
Property and equipment, net		$ 8,221	$ 7,376
National Holdings [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment	$ 2,506
Less: accumulated depreciation	(314)
Property and equipment, net	2,192
Equipment [Member] \| National Holdings [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment	1,305
Furniture And Fixtures [Member] \| National Holdings [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment	$ 240
Property, Plant and Equipment, Estimated Useful Lives	5 years
Leaseholds And Leasehold Improvements [Member] \| National Holdings [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment	$ 685
Property, Plant and Equipment, Estimated Useful Lives	Lesser of useful life or term of lease
Capital leases (primarily composed of computer equipment) [Member] \| National Holdings [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment	$ 276
Property, Plant and Equipment, Estimated Useful Lives	5 years
National Holdings Corporation [Member] \| Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Estimated Useful Lives	5 years

Property and Equipment - Additi

Property and Equipment - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Property, Plant and Equipment [Line Items]
Depreciation	$ 200	$ 200	$ 819	$ 240
Property, Plant and Equipment, Design Costs Capitalized	$ 100		$ 100

Fair Value Measurements - Warra

Fair Value Measurements - Warrant Liabilities And Convertible Notes At Fair Value (Detail) - $ / shares	6 Months Ended	9 Months Ended
	Jun. 30, 2017	Sep. 30, 2017
Warrants Issuable [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Risk-free interest rate	1.89%
Expected dividend yield	0.00%
Expected term in years	4 years 2 months 12 days
Expected volatility	91.00%
Helocyte [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Expected dividend yield		0.00%
Expected volatility		70.00%
Strike price		$ 0.44
Helocyte [Member] \| Convertible Debt [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Expected dividend yield		0.00%
Expected volatility		59.50%
Helocyte [Member] \| Minimum [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Risk-free interest rate		1.733%
Expected term in years		3 years 9 months
Helocyte [Member] \| Minimum [Member] \| Convertible Debt [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Risk-free interest rate		1.199%
Expected term in years		6 months
Helocyte [Member] \| Maximum [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Risk-free interest rate		1.795%
Expected term in years		4 years 2 months 1 day
Helocyte [Member] \| Maximum [Member] \| Convertible Debt [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Risk-free interest rate		1.336%
Expected term in years		1 year 1 month 28 days
Caelum Warrant Liabilities [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Expected dividend yield		0.00%
Expected volatility		70.00%
Strike price		$ 1.43
Caelum Warrant Liabilities [Member] \| Minimum [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Risk-free interest rate		1.895%
Expected term in years		4 years 10 months 2 days
Caelum Warrant Liabilities [Member] \| Maximum [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Risk-free interest rate		1.914%
Expected term in years		4 years 11 months 16 days
Caelum Convertible Notes [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Expected dividend yield		0.00%
Expected volatility		70.00%
Caelum Convertible Notes [Member] \| Minimum [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Risk-free interest rate		1.246%
Expected term in years		8 months 16 days
Caelum Convertible Notes [Member] \| Maximum [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Risk-free interest rate		1.463%
Expected term in years		1 year 11 months 12 days

Fair Value Measurements - Deriv

Fair Value Measurements - Derivative Contingently Issuable Warrant liabilities (Detail) - USD ($) $ in Thousands	6 Months Ended	9 Months Ended
	Jun. 30, 2017	Sep. 30, 2017
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Conversion into common shares		$ (1,064)
National [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair value at the beginning of period:	$ 14,359	14,359
Change in fair value	(5,527)
Fair value at end of period:	8,832
Avenue [Member] \| Convertible Debt [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair value at the beginning of period:	200	200
Conversion into common shares		(299)
Change in fair value		99
Fair value at end of period:		0
Avenue [Member] \| Contingently Issuable Warrants [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair value at the beginning of period:	302	302
Conversion into common shares		(750)
Change in fair value		448
Fair value at end of period:		0
Avenue [Member] \| Warrant [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair value at the beginning of period:	12	12
Conversion into common shares		(15)
Change in fair value		3
Fair value at end of period:		0
Helocyte [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair value at the beginning of period:	167	167
Change in fair value		(79)
Fair value at end of period:		88
Helocyte [Member] \| Convertible Debt [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair value at the beginning of period:	4,487	4,487
Change in fair value		246
Fair value at end of period:		4,733
Caelum Warrant Liabilities [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair value at the beginning of period:	0	0
Change in fair value		225
Fair value at end of period:		225
Caelum Convertible Notes [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair value at the beginning of period:	$ 0	0
Additions		9,914
Change in fair value		14
Fair value at end of period:		$ 9,928

Fair Value Measurements - Natio

Fair Value Measurements - National Financial Instruments Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	Sep. 30, 2017	Jun. 30, 2017	Dec. 31, 2016
Assets
Long-term investments, at fair value	$ 923		$ 1,414
Total	923		1,414
Liabilities
Liabilities	14,974		5,168
National Holdings Corporation [Member]
Assets
Total		$ 1,595
Liabilities
Liabilities		9,469
Contingently Issuable Warrant [Member]
Liabilities
Liabilities			302
Warrant [Member]
Liabilities
Liabilities	313		179
Helocyte Convertible Note One [Member]
Liabilities
Liabilities	4,733		4,487
Avenue Convertible Note [Member]
Liabilities
Liabilities			200
Corporate stock Assets [Member] \| National Holdings Corporation [Member]
Assets
Total		70
Municipal bonds Assets [Member] \| National Holdings Corporation [Member]
Assets
Total		1,333
Restricted stock Assets [Member] \| National Holdings Corporation [Member]
Assets
Total		192
Warrants Issuable [Member] \| National Holdings Corporation [Member]
Liabilities
Liabilities		8,832
Contingent Consideration [Member] \| National Holdings Corporation [Member]
Liabilities
Liabilities		637
Caelum Convertible Notes [Member]
Liabilities
Liabilities	9,928
Fair Value, Inputs, Level 1 [Member]
Assets
Long-term investments, at fair value	0		0
Total	0		0
Liabilities
Liabilities	0		0
Fair Value, Inputs, Level 1 [Member] \| National Holdings Corporation [Member]
Assets
Total		886
Liabilities
Liabilities		0
Fair Value, Inputs, Level 1 [Member] \| Contingently Issuable Warrant [Member]
Liabilities
Liabilities			0
Fair Value, Inputs, Level 1 [Member] \| Warrant [Member]
Liabilities
Liabilities	0		0
Fair Value, Inputs, Level 1 [Member] \| Helocyte Convertible Note One [Member]
Liabilities
Liabilities	0		0
Fair Value, Inputs, Level 1 [Member] \| Avenue Convertible Note [Member]
Liabilities
Liabilities			0
Fair Value, Inputs, Level 1 [Member] \| Corporate stock Assets [Member] \| National Holdings Corporation [Member]
Assets
Total		70
Fair Value, Inputs, Level 1 [Member] \| Municipal bonds Assets [Member] \| National Holdings Corporation [Member]
Assets
Total		816
Fair Value, Inputs, Level 1 [Member] \| Restricted stock Assets [Member] \| National Holdings Corporation [Member]
Assets
Total		0
Fair Value, Inputs, Level 1 [Member] \| Warrants Issuable [Member] \| National Holdings Corporation [Member]
Liabilities
Liabilities		0
Fair Value, Inputs, Level 1 [Member] \| Contingent Consideration [Member] \| National Holdings Corporation [Member]
Liabilities
Liabilities		0
Fair Value, Inputs, Level 1 [Member] \| Caelum Convertible Notes [Member]
Liabilities
Liabilities	0
Fair Value, Inputs, Level 2 [Member]
Assets
Long-term investments, at fair value	0		0
Total	0		0
Liabilities
Liabilities	0		0
Fair Value, Inputs, Level 2 [Member] \| National Holdings Corporation [Member]
Assets
Total		709
Liabilities
Liabilities		0
Fair Value, Inputs, Level 2 [Member] \| Contingently Issuable Warrant [Member]
Liabilities
Liabilities			0
Fair Value, Inputs, Level 2 [Member] \| Warrant [Member]
Liabilities
Liabilities	0		0
Fair Value, Inputs, Level 2 [Member] \| Helocyte Convertible Note One [Member]
Liabilities
Liabilities	0		0
Fair Value, Inputs, Level 2 [Member] \| Avenue Convertible Note [Member]
Liabilities
Liabilities			0
Fair Value, Inputs, Level 2 [Member] \| Corporate stock Assets [Member] \| National Holdings Corporation [Member]
Assets
Total		0
Fair Value, Inputs, Level 2 [Member] \| Municipal bonds Assets [Member] \| National Holdings Corporation [Member]
Assets
Total		517
Fair Value, Inputs, Level 2 [Member] \| Restricted stock Assets [Member] \| National Holdings Corporation [Member]
Assets
Total		192
Fair Value, Inputs, Level 2 [Member] \| Contingent Consideration [Member] \| National Holdings Corporation [Member]
Liabilities
Liabilities		0
Fair Value, Inputs, Level 2 [Member] \| Caelum Convertible Notes [Member]
Liabilities
Liabilities	0
Fair Value, Inputs, Level 3 [Member]
Assets
Long-term investments, at fair value	923		1,414
Total	923		1,414
Liabilities
Liabilities	14,974		5,168
Fair Value, Inputs, Level 3 [Member] \| National Holdings Corporation [Member]
Assets
Total		0
Liabilities
Liabilities		9,469
Fair Value, Inputs, Level 3 [Member] \| Contingently Issuable Warrant [Member]
Liabilities
Liabilities			302
Fair Value, Inputs, Level 3 [Member] \| Warrant [Member]
Liabilities
Liabilities	313		179
Fair Value, Inputs, Level 3 [Member] \| Helocyte Convertible Note One [Member]
Liabilities
Liabilities	4,733		4,487
Fair Value, Inputs, Level 3 [Member] \| Avenue Convertible Note [Member]
Liabilities
Liabilities			$ 200
Fair Value, Inputs, Level 3 [Member] \| Corporate stock Assets [Member] \| National Holdings Corporation [Member]
Assets
Total		0
Fair Value, Inputs, Level 3 [Member] \| Municipal bonds Assets [Member] \| National Holdings Corporation [Member]
Assets
Total		0
Fair Value, Inputs, Level 3 [Member] \| Restricted stock Assets [Member] \| National Holdings Corporation [Member]
Assets
Total		0
Fair Value, Inputs, Level 3 [Member] \| Warrants Issuable [Member] \| National Holdings Corporation [Member]
Liabilities
Liabilities		8,832
Fair Value, Inputs, Level 3 [Member] \| Contingent Consideration [Member] \| National Holdings Corporation [Member]
Liabilities
Liabilities		$ 637
Fair Value, Inputs, Level 3 [Member] \| Caelum Convertible Notes [Member]
Liabilities
Liabilities	$ 9,928

Fair Value Measurements - Chang

Fair Value Measurements - Changes in Fair Value of Financial Instruments (Detail) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance	$ 20,941
Additions during the period	10,139
Conversion into common shares	(1,064)
Issuance of warrants	0
Loss on write off investment	(250)	$ 0
Change in fair value of investments	(241)
Change in fair value of convertible notes	359
Change in fair value of derivative liabilities	(5,155)
Balance	24,729
Contingently Issuable Warrant [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance	14,661
Additions during the period	0
Conversion into common shares	(750)
Issuance of warrants	(8,190)
Loss on write off investment	0
Change in fair value of investments	0
Change in fair value of convertible notes	0
Change in fair value of derivative liabilities	(5,079)
Balance	642
Helocyte Convertible Note At Fair Value [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance	4,487
Additions during the period	0
Conversion into common shares	0
Issuance of warrants	0
Loss on write off investment	0
Change in fair value of investments	0
Change in fair value of convertible notes	246
Change in fair value of derivative liabilities	0
Balance	4,733
Avenue Convertible Note, at fair value [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance	200
Additions during the period	0
Conversion into common shares	(299)
Issuance of warrants	0
Loss on write off investment	0
Change in fair value of investments	0
Change in fair value of convertible notes	99
Change in fair value of derivative liabilities	0
Balance	0
Caelum Convertible Notes [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance	0
Additions during the period	9,914
Conversion into common shares	0
Issuance of warrants	0
Loss on write off investment	0
Change in fair value of investments	0
Change in fair value of convertible notes	14
Change in fair value of derivative liabilities	0
Balance	9,928
Warrant liabilities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance	179
Additions during the period	225
Conversion into common shares	(15)
Issuance of warrants	8,190
Loss on write off investment	0
Change in fair value of investments	0
Change in fair value of convertible notes	0
Change in fair value of derivative liabilities	(76)
Balance	8,503
Investment In Laser Device [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance	250
Additions during the period	0
Conversion into common shares	0
Issuance of warrants	0
Loss on write off investment	(250)
Change in fair value of investments	0
Change in fair value of convertible notes	0
Change in fair value of derivative liabilities	0
Balance	0
Investment In Origo [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance	1,164
Additions during the period	0
Conversion into common shares	0
Issuance of warrants	0
Loss on write off investment	0
Change in fair value of investments	(241)
Change in fair value of convertible notes	0
Change in fair value of derivative liabilities	0
Balance	$ 923

Fair Value Measurements - Addit

Fair Value Measurements - Additional Information (Detail) - USD ($)	Jun. 26, 2017	Jun. 26, 2017	Mar. 17, 2014	Sep. 30, 2017	Dec. 31, 2016	Dec. 30, 2016
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Method Investments			$ 300,000	$ 0	$ 300,000
Equity Method Investment, Ownership Percentage			35.00%
Investments in and Advances to Affiliates, at Fair Value, Period Increase (Decrease), Total				200,000
Investment Owned, at Fair Value				$ 1,595,000	$ 2,357,000
Class of Warrant or Right, Exercise Price of Warrants or Rights	$ 4.02	$ 4.02
Equity Securities Called by Warrant						$ 10,000
Common Stock Par Or Stated Value Per Share				$ 0.001	$ 0.001
Exercise Price Of Warrant Discount Percentage	33.00%	33.00%
Debt Conversion, Converted Instrument, Shares Issued	49,749
Investment Write down			$ 300,000
IPO [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Stock Issued During Period, Shares, New Issues		6,325,000
Origo Acquisition Corporation [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment Owned, at Fair Value				$ 900,000
Fair Value Assumptions Probability Of Business Combination				31.40%
Working Capital Note Convertible To Equity				$ 300,000
National Holdings Corporation [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Percentage of Outstanding Stock To Be Issued Upon Exercise of Warrants				43.40%
Percentage of outstanding shares, Tendered				80.00%
Class of Warrant or Right, Exercise Price of Warrants or Rights				$ 3.25
Warrants Not Settleable in Cash, Fair Value Disclosure				$ 5,400,000
Debt Instrument, Face Amount	$ 3,000,000	$ 3,000,000
Class of Warrant or Right, Number of Securities Called by Warrants or Rights	125,000	125,000
Avenue Therapeutics, Inc. [Member] \| IPO [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Stock Issued During Period, Value, New Issues		$ 38,000,000
Stock Issued During Period, Shares, New Issues		6,300,000
Common Stock Par Or Stated Value Per Share	$ 6	$ 6
Westpark [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Class of Warrant or Right, Exercise Price of Warrants or Rights	4.02	4.02
Common Stock Par Or Stated Value Per Share	$ 6	$ 6
Class of Warrant or Right, Number of Securities Called by Warrants or Rights	2,488	2,488
Exercise Price Of Warrant Discount Percentage	33.00%	33.00%
Binomial Lattice Model [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Assumptions, Exercise Price				$ 0.33
Binomial Lattice Model [Member] \| Warrant [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Business Acquisition, Share Price				0.31
Private Units [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Share Price				$ 10.61
Argus Neurooptics Llc [Member] \| Class A Preferred Stock [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Shares Received Under Purchase Agreement			$ 13,409,962
Percentage Of Shares Received Under Purchase Agreement			83.00%
Preferred Units, Issued			16,091,954

Licenses Acquired - Summary Of

Licenses Acquired - Summary Of Research and Development Arrangement Contract (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Research and Development Total	$ 300	$ 1,000	$ 3,394	$ 3,143
Fortress [Member]
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Research and Development Total	0	0	300	0
Checkpoint Therapeutics, Inc [Member]
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Research and Development Total	0	1,000	400	3,060
Helocyte [Member]
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Research and Development Total	0	0	0	83
Mustang Therapeutics, Inc [Member]
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Research and Development Total	300	0	2,375	0
Caelum Biosciences, Inc. [Member]
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Research and Development Total	0	0	219	0
Cyprium Therapeutics, Inc. [Member]
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Research and Development Total	$ 0	$ 0	$ 100	$ 0

Licenses Acquired - Additional

Licenses Acquired - Additional Information (Detail) - USD ($)

Jul. 03, 2017

May 31, 2017

Apr. 25, 2017

Mar. 31, 2017

Mar. 17, 2017

Feb. 17, 2017

Jan. 31, 2017

Dec. 31, 2016

Sep. 30, 2016

Sep. 30, 2017

Sep. 30, 2016

Sep. 30, 2017

Sep. 30, 2016

Research and Development Arrangement, Contract to Perform for Others [Line Items]

Research And Development In Process

$ 300,000

$ 1,000,000

$ 3,394,000

$ 3,143,000

City Of Hope [Member]

Research and Development Arrangement, Contract to Perform for Others [Line Items]

Payments for Fees

$ 100,000

Revenue Recognition Milestone Method Payments Due

100,000

Effcon Laboratories, Inc [Member]

Research and Development Arrangement, Contract to Perform for Others [Line Items]

Research And Development In Process

300,000

Payment of Upfront Fees

$ 200,000

Revenue Recognition Milestone Method Payments Due

$ 2,300,000

Royalty Guarantees, Commitments, Amount

$ 1,600,000

1,600,000

Jubilant Biosys Ltd [Member]

Research and Development Arrangement, Contract to Perform for Others [Line Items]

Research And Development In Process

400,000

Royalty Revenue

$ 200,000

300,000

$ 800,000

1,300,000

National Institute of Child Health and Human Development [Member]

Research and Development Arrangement, Contract to Perform for Others [Line Items]

Payment of Upfront Milestone Fees

$ 100,000

Columbia University [Member]

Research and Development Arrangement, Contract to Perform for Others [Line Items]

Stock Issued During Period, Shares, Purchase of Assets

1,050,000

Shares Issued, Price Per Share

$ 0.028

Stock Issued During Period, Value, Purchase of Assets

$ 29,000

Payment of Upfront Milestone Fees

$ 200,000

Revenue Recognition Milestone Method Payments Due

$ 5,500,000

Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners

10.00%

Collaborative Agreements with TGTX [Member] | NeuPharma [Member]

Research and Development Arrangement, Contract to Perform for Others [Line Items]

Payments for Fees

$ 46,000

84,000

20,000

Checkpoint Therapeutics, Inc [Member]

Research and Development Arrangement, Contract to Perform for Others [Line Items]

Research And Development In Process

$ 0

$ 1,000,000

$ 400,000

3,060,000

Payment of Upfront Fees

$ 2,000,000

Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners

[1]

63.50%

[2]

61.90%

63.50%

[2]

61.90%

63.50%

[2]

Checkpoint Therapeutics, Inc [Member] | Dana-Farber [Member]

Research and Development Arrangement, Contract to Perform for Others [Line Items]

Stock Issued During Period, Value, Purchase of Assets

$ 0

UCLA License [Member]

Research and Development Arrangement, Contract to Perform for Others [Line Items]

Revenue Recognition Milestone Method Payments Due

$ 14,300,000

UCLA License [Member] | University of California [Member]

Research and Development Arrangement, Contract to Perform for Others [Line Items]

Payment of Upfront Fees

$ 200,000

A&R CD123 License [Member] | City Of Hope [Member]

Research and Development Arrangement, Contract to Perform for Others [Line Items]

Revenue Recognition Milestone Method Payments Due

14,500,000

A&R IL-13 License [Member] | City Of Hope [Member]

Research and Development Arrangement, Contract to Perform for Others [Line Items]

Research And Development In Process

$ 300,000

Revenue Recognition Milestone Method Payments Due

$ 14,500,000

CS1 Technology License [Member]

Research and Development Arrangement, Contract to Perform for Others [Line Items]

Payment of Upfront Fees

$ 600,000

Revenue Recognition Milestone Method Payments Due

$ 14,900,000

Annual Maintenance Fee Payable

50,000

PSCA Technology License [Member]

Research and Development Arrangement, Contract to Perform for Others [Line Items]

Payment of Upfront Fees

300,000

Revenue Recognition Milestone Method Payments Due

14,900,000

Annual Maintenance Fee Payable

50,000

HER2 Technology License [Member]

Research and Development Arrangement, Contract to Perform for Others [Line Items]

Payment of Upfront Fees

600,000

Revenue Recognition Milestone Method Payments Due

14,900,000

Annual Maintenance Fee Payable

$ 50,000

Fred Hutchinson Cancer Research Center License [Member]

Research and Development Arrangement, Contract to Perform for Others [Line Items]

Payment of Upfront Fees

$ 300,000

Revenue Recognition Milestone Method Payments Due

39,100,000

Annual Maintenance Fee Payable

$ 50,000

[1]

Checkpoint is consolidated with Fortress’s operations because Fortress maintains voting control through its ownership of Checkpoint’s Class A common shares which provide for super-majority voting rights

[2]

Represents a weighted average of ownership during the periods presented

Intangibles, net - Additional I

Intangibles, net - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Indefinite-lived Intangible Assets [Line Items]
Payments to Acquire Intangible Assets			$ 0	$ 350
Cost of Goods Sold, Amortization			401	50
Journey Medical Corporation [Member]
Indefinite-lived Intangible Assets [Line Items]
Payments to Acquire Intangible Assets			1,600
Cost of Goods Sold, Amortization	$ 100	$ 29	$ 400	$ 50

Debt and Interest - Long-term d

Debt and Interest - Long-term debt (Detail) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017	Dec. 31, 2016
Debt [Line Items]
Total notes payable	$ 67,445	$ 30,224
Less: Discount of notes payable	3,827	2,009
Total notes payable, net	63,618	28,215
IDB Note [Member]
Debt [Line Items]
Total notes payable	$ 14,929	14,929
Interest Rate	2.25%
Maturity Date	Feb - 2018
NSC Note [Member]
Debt [Line Items]
Total notes payable	$ 0	3,608
Interest Rate	8.00%
Maturity Date	Sep - 2018
2017 Subordinated Note Financing One [Member]
Debt [Line Items]
Total notes payable	$ 3,254	0
Interest Rate	8.00%
Maturity Date	March - 2020
2017 Subordinated Note Financing Two [Member]
Debt [Line Items]
Total notes payable	$ 13,893	0
Interest Rate	8.00%
Maturity Date	May - 2020
2017 Subordinated Note Financing Three [Member]
Debt [Line Items]
Total notes payable	$ 1,820	0
Interest Rate	8.00%
Maturity Date	June - 2020
2017 Subordinated Note Financing Four [Member]
Debt [Line Items]
Total notes payable	$ 3,017	0
Interest Rate	8.00%
Maturity Date	August - 2020
2017 Subordinated Note Financing Five [Member]
Debt [Line Items]
Total notes payable	$ 6,371	0
Interest Rate	8.00%
Maturity Date	September - 2020
Helocyte Convertible Note four [Member]
Debt [Line Items]
Total notes payable	$ 436	414
Maturity Date	May - 2018
Helocyte Convertible Note four [Member] \| Minimum [Member]
Debt [Line Items]
Interest Rate	5.00%
Helocyte Convertible Note four [Member] \| Maximum [Member]
Debt [Line Items]
Interest Rate	8.00%
Avenue Convertible Note [Member]
Debt [Line Items]
Total notes payable	$ 0	200
Maturity Date	June - 2018
Avenue Convertible Note [Member] \| Minimum [Member]
Debt [Line Items]
Interest Rate	5.00%
Avenue Convertible Note [Member] \| Maximum [Member]
Debt [Line Items]
Interest Rate	8.00%
Opus Credit Facility [Member]
Debt [Line Items]
Total notes payable	$ 9,500	7,000
Interest Rate	12.00%
Maturity Date	Sep - 2018
Helocyte Convertible Note One [Member]
Debt [Line Items]
Total notes payable	$ 1,084	1,031
Maturity Date	December 2,017
Helocyte Convertible Note One [Member] \| Minimum [Member]
Debt [Line Items]
Interest Rate	5.00%
Helocyte Convertible Note One [Member] \| Maximum [Member]
Debt [Line Items]
Interest Rate	8.00%
Helocyte Convertible Note Two [Member]
Debt [Line Items]
Total notes payable	$ 2,164	2,051
Maturity Date	March - 2018
Helocyte Convertible Note Two [Member] \| Minimum [Member]
Debt [Line Items]
Interest Rate	5.00%
Helocyte Convertible Note Two [Member] \| Maximum [Member]
Debt [Line Items]
Interest Rate	8.00%
Caelum Convertible Note one [Member]
Debt [Line Items]
Total notes payable	$ 1,004	0
Interest Rate	8.00%
Maturity Date	January - 2019
Caelum Convertible Note Two [Member]
Debt [Line Items]
Total notes payable	$ 6,810	0
Interest Rate	8.00%
Maturity Date	February (2,019)
Caelum Convertible Note one Three [Member]
Debt [Line Items]
Total notes payable	$ 2,114	0
Interest Rate	8.00%
Maturity Date	June - 2019
Helocyte Convertible Note Three [Member]
Debt [Line Items]
Total notes payable	$ 1,049	$ 991
Maturity Date	April - 2018
Helocyte Convertible Note Three [Member] \| Minimum [Member]
Debt [Line Items]
Interest Rate	5.00%
Helocyte Convertible Note Three [Member] \| Maximum [Member]
Debt [Line Items]
Interest Rate	8.00%

Debt and Interest - Schedule of

Debt and Interest - Schedule of Interest Expenses for Debt Arrangements (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Debt [Line Items]
Total Interest Expense and Financing Fee	$ 3,220	$ 689	$ 5,298	$ 1,838
LOC Fees [Member]
Debt [Line Items]
Interest	7	3	22	10
Interest and Debt Expense	7	3	22	10
IDB Note [Member]
Debt [Line Items]
Interest	85	84	254	243
Amortization of fees	0	0	0	1
Interest and Debt Expense	85	84	254	244
NSC Debt [Member]
Debt [Line Items]
Interest	(8)	145	147	456
Amortization of fees	127	135	200	557
Interest and Debt Expense	119	280	347	1,013
2017 Subordinated Note [Member]
Debt [Line Items]
Interest	755	0	1,161	0
Amortization of fees	208	0	383	0
Interest and Debt Expense	963	0	1,544	0
Opus Credit Facility [Member]
Debt [Line Items]
Interest	287	26	798	26
Amortization of fees	282	28	733	28
Interest and Debt Expense	569	54	1,531	54
Avenue Convertible Note [Member]
Debt [Line Items]
Interest	0	0	5	0
Financing fee	0	0	3	0
Interest and Debt Expense	0	0	8	0
Helocyte Convertible Note [Member]
Debt [Line Items]
Interest	64	26	175	26
Financing fee	0	242	1	491
Interest and Debt Expense	64	268	176	517
D&O Insurance [Member]
Debt [Line Items]
Interest	2	0	5	0
Interest and Debt Expense	2	0	5	0
Caelum Convertible Notes [Member]
Debt [Line Items]
Interest	68	0	68	0
Financing fee	1,317	0	1,317	0
Interest and Debt Expense	1,385	0	1,385	0
Falk CSR [Member]
Debt [Line Items]
Interest	26	0	26	0
Interest and Debt Expense	$ 26	$ 0	$ 26	$ 0

Debt and Interest- Additional I

Debt and Interest- Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	Jul. 05, 2017	May 01, 2017	Sep. 30, 2017	Aug. 31, 2017	Jul. 31, 2017	Jun. 30, 2017	May 31, 2017	Mar. 31, 2017	Mar. 17, 2017	Sep. 30, 2017	Sep. 30, 2017	Sep. 30, 2016	Jun. 26, 2017	Dec. 31, 2016	Feb. 13, 2014
Debt [Line Items]
Warrant exercise price													$ 4.02
Proceeds from Notes Payable											$ 0	$ 920
Notes Payable			$ 63,618							$ 63,618	63,618			$ 28,215
Proceeds From Convertible Debt											9,914	3,018
Payments of Financing Costs											$ 1,081	$ 0
Class of Warrant or Right, Exercise Price of Warrants or Rights													$ 4.02
Maximum [Member]
Debt [Line Items]
Warrant exercise price			$ 4.75							$ 4.75	$ 4.75
Class of Warrant or Right, Exercise Price of Warrants or Rights			$ 4.75							$ 4.75	$ 4.75
Israel Discount Bank Of New York [Member]
Debt [Line Items]
Debt Instrument, Face Amount															$ 15,000
Notes Payable			$ 14,900							$ 14,900	$ 14,900
Debt Instrument, Collateral Amount			15,000							15,000	15,000
Opus Credit Facility [Member]
Debt [Line Items]
Class Of Warrant Or Right Discount On Warrant			1,300							1,300	1,300
Warrants and Rights Outstanding			$ 9,500							$ 9,500	$ 9,500
NSC 2017 Note [Member]
Debt [Line Items]
Warrant exercise price								$ 3.70
Debt Instrument, Interest Rate, Stated Percentage								8.00%
Debt Instrument, Face Amount								$ 3,250
Debt Instrument, Maturity Date, Description											Each Note is due on the third anniversary of its issuance, provided that the Company may extend the maturity date for two one-year periods in its sole discretion
Paid-in-Kind Interest, Percentage								7.00%
Line of Credit Facility, Current Borrowing Capacity								$ 50,000
Percentage Of Placement Agent Fee									10.00%		10.00%
Warrant On Sale Price Of Note Percentage			10.00%						10.00%	10.00%	10.00%
Proceeds from Fees Received								$ 300
Class of Warrant or Right, Number of Securities Called by Warrants or Rights			716,180							716,180	716,180
Class of Warrant or Right, Exercise Price of Warrants or Rights								$ 3.70
NSC 2017 Note [Member] \| First Closing [Member]
Debt [Line Items]
Proceeds from Issuance of Debt								$ 3,200
NSC 2017 Note [Member] \| Secoud Closing [Member]
Debt [Line Items]
Warrant exercise price		$ 3.65
Proceeds from Notes Payable		$ 8,600
Proceeds from Fees Received		$ 900
Class of Warrant or Right, Number of Securities Called by Warrants or Rights		234,438	87,946							87,946	87,946
Class of Warrant or Right, Exercise Price of Warrants or Rights		$ 3.65
NSC 2017 Note [Member] \| Third Closing [Member]
Debt [Line Items]
Warrant exercise price							$ 3.61
Proceeds from Notes Payable							$ 5,300
Proceeds from Fees Received							$ 500
Class of Warrant or Right, Number of Securities Called by Warrants or Rights							147,806
Class of Warrant or Right, Exercise Price of Warrants or Rights							$ 3.61
NSC 2017 Note [Member] \| Fourth Closing [Member]
Debt [Line Items]
Warrant exercise price						$ 4.75
Proceeds from Notes Payable						$ 1,800
Proceeds from Fees Received						$ 200
Class of Warrant or Right, Number of Securities Called by Warrants or Rights						38,315
Class of Warrant or Right, Exercise Price of Warrants or Rights						$ 4.75
NSC 2017 Note [Member] \| Fifth Closing [Member]
Debt [Line Items]
Warrant exercise price				$ 4.75
Proceeds from Notes Payable				$ 3,000
Proceeds from Fees Received				$ 300
Class of Warrant or Right, Number of Securities Called by Warrants or Rights				63,526
Class of Warrant or Right, Exercise Price of Warrants or Rights				$ 4.75
NSC 2017 Note [Member] \| Sixth Closing [Member]
Debt [Line Items]
Warrant exercise price			$ 4.42							$ 4.42	$ 4.42
Proceeds from Notes Payable			$ 6,400
Proceeds from Fees Received			$ 600
Class of Warrant or Right, Number of Securities Called by Warrants or Rights			144,149							144,149	144,149
Class of Warrant or Right, Exercise Price of Warrants or Rights			$ 4.42							$ 4.42	$ 4.42
NSC 2017 Note [Member] \| Maximum [Member]
Debt [Line Items]
Debt Instrument, Face Amount								$ 40,000
Caelum Convertible Notes [Member]
Debt [Line Items]
Debt Instrument, Face Amount					$ 10,000
Debt Instrument Issuance, Percentage of Commission					10.00%
Proceeds From Convertible Debt					$ 9,900					$ 9,900
Payments of Financing Costs					$ 900					$ 900
Class of Warrant or Right, Percentage Securities Called by Warrants or Rights					10.00%					10.00%
Class of Warrant or Right, Exercise Price percentage					110.00%					110.00%
Class of Warrant or Right, Exercise Price Description											the exercise price will be $75 million dollars divided by the total number of fully-diluted shares of Common Stock outstanding immediately prior to exercise of the warrant, giving effect to the assumed conversion of all options, warrants, and convertible securities of the Company
Debt Conversion, Description											The notes convert upon a qualified financing in which Caelum raises gross proceeds of at least $10 million as follows: the lesser of (a) a discount to the price per common share being paid in the Sale of the Company equal to 20% or (b) a conversion price per share based on a pre-sale valuation of $75,000,000 divided by the number of common shares outstanding at that time assuming the hypothetical conversion or exercise of any convertible securities, options, warrants and other rights to acquire common shares of the Company.
NSC [Member]
Debt [Line Items]
Repayments of Debt	$ 3,600

Accrued Expenses and Other Lo62

Accrued Expenses and Other Long-Term Liabilities - Components of Accrued Expenses and Other Long-Term Liabilities (Detail) - USD ($) $ in Thousands		Sep. 30, 2017	Dec. 31, 2016
Accrued expenses:
Professional fees		$ 1,297	$ 1,253
Salaries, bonuses and related benefits		4,178	2,846
Accrued Severance		0	53
Accrued Legal Settlement	[1]	2,212	0
Ovamed manufacturing rights - short term component		0	900
Research and development		3,311	394
Dr. Falk Pharma milestone		2,950	2,634
Other		2,703	2,002
Total accrued expenses		16,651	10,082
Other long-term liabilities:
Deferred rent and long-term lease abandonment charge		4,736	5,014
Total other long-term liabilities		$ 4,736	$ 5,014

[1]	In connection with a legal settlement (see Note 16), the Company is required to deliver 200,000 Mustang common shares, held by the Company, to the Plaintiff. At September 30, 2017, the Company recorded, this settlement as an accrued, since in accordance with ASC 450 Contingencies, the transfer of the consideration was probable. As such the Company recorded an accrued expense of $2.0 million representing the value of the shares transferred.

Accrued Expenses and Other Lo63

Accrued Expenses and Other Long-Term Liabilities- Accounts Payable and Other Accrued Expenses (Detail) - USD ($) $ in Thousands	Sep. 30, 2017	Jun. 30, 2017	Dec. 31, 2016
Legal	$ 1,297		$ 1,253
Other	2,703		2,002
Total	$ 31,978		$ 23,871
National Holdings Corporation [Member]
Legal		$ 836
Audit		148
Telecommunications		196
Data Services		450
Regulatory		661
Settlements		2,633
Deferred rent		177
Contingent consideration payable		636
Income taxes payable		927
Other		1,844
Total		$ 8,508

Accrued Expenses and Other Lo64

Accrued Expenses and Other Long-Term Liabilities - Additional Information (Detail) - USD ($) $ in Thousands		Sep. 30, 2017	Dec. 31, 2016
Schedule Accrued Expenses And Other Long-Term Liabilities [Line Items]
Estimated Litigation Liability, Current	[1]	$ 2,212	$ 0
Mustang Common Shares [Member]
Schedule Accrued Expenses And Other Long-Term Liabilities [Line Items]
Number of Shares To Be Issued Upon Legal Settlement		200,000

[1]	In connection with a legal settlement (see Note 16), the Company is required to deliver 200,000 Mustang common shares, held by the Company, to the Plaintiff. At September 30, 2017, the Company recorded, this settlement as an accrued, since in accordance with ASC 450 Contingencies, the transfer of the consideration was probable. As such the Company recorded an accrued expense of $2.0 million representing the value of the shares transferred.

Non-Controlling Interests - Sum

Non-Controlling Interests - Summary Of Non-controlling Interests in Consolidated Entities (Detail) - USD ($) $ 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
Noncontrolling Interest [Line Items]
NCI equity share				$ 101,676			$ 60,668
Net loss attributed to non-controlling interests	$ (9,191)		$ (3,975)	(17,355)		$ (12,324)	(16,195)
Non-controlling interests in consolidated entities	84,321			84,321			44,473
Avenue [Member]
Noncontrolling Interest [Line Items]
NCI equity share				17,306			(494)
Net loss attributed to non-controlling interests	(1,015)	[1]	(47)	(1,329)		(231)	(349)
Non-controlling interests in consolidated entities	15,977			15,977			(843)
Coronado SO Co, Inc [Member]
Noncontrolling Interest [Line Items]
NCI equity share				(236)			(217)
Net loss attributed to non-controlling interests	(15)		(4)	(22)		(14)	(19)
Non-controlling interests in consolidated entities	(258)			(258)			(236)
Mustang Therapeutics, Inc [Member]
Noncontrolling Interest [Line Items]
NCI equity share				47,840			12,376
Net loss attributed to non-controlling interests	(3,241)	[1]	(204)	(8,268)		(363)	(1,805)
Non-controlling interests in consolidated entities	39,572			39,572			10,571
Checkpoint Therapeutics, Inc [Member]
Noncontrolling Interest [Line Items]
NCI equity share				22,368			32,160
Net loss attributed to non-controlling interests	(3,437)	[2]	(3,254)	(10,144)	[2]	(10,767)	(11,733)
Non-controlling interests in consolidated entities	12,224			12,224			20,427
JMC [Member]
Noncontrolling Interest [Line Items]
NCI equity share				(535)			(192)
Net loss attributed to non-controlling interests	(103)		(104)	(150)		(333)	(355)
Non-controlling interests in consolidated entities	(685)			(685)			(547)
Helocyte [Member]
Noncontrolling Interest [Line Items]
NCI equity share				(1,848)			(612)
Net loss attributed to non-controlling interests	(376)		$ (362)	(975)		$ (616)	(1,155)
Non-controlling interests in consolidated entities	(2,823)			(2,823)			(1,767)
Cellvation [Member]
Noncontrolling Interest [Line Items]
NCI equity share				(239)			4
Net loss attributed to non-controlling interests	24			(60)			(158)
Non-controlling interests in consolidated entities	(299)			(299)			(154)
Caelum [Member]
Noncontrolling Interest [Line Items]
NCI equity share				7
Net loss attributed to non-controlling interests	(835)			(1,086)
Non-controlling interests in consolidated entities	(1,079)			(1,079)
National Holdings [Member]
Noncontrolling Interest [Line Items]
NCI equity share				17,022			17,643
Net loss attributed to non-controlling interests	(27)			4,845			(621)
Non-controlling interests in consolidated entities	21,867			21,867			$ 17,022
Aevitas [Member]
Noncontrolling Interest [Line Items]
NCI equity share				(9)
Net loss attributed to non-controlling interests	(166)			(166)
Non-controlling interests in consolidated entities	$ (175)			$ (175)

[1]	Mustang and Avenue are consolidated with Fortress’s operations because Fortress maintains voting control through its ownership of Mustang’s and Avenue’s Class A preferred shares which provide super-majority voting rights.
[2]	Checkpoint is consolidated with Fortress’s operations because Fortress maintains voting control through its ownership of Checkpoint’s Class A common shares which provide for super-majority voting rights

Non-Controlling Interests - S66

Non-Controlling Interests - Summary Of Components of Non-Controlling Interests in Loss of Consolidated Entities (Detail) - USD ($) $ 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
Noncontrolling Interest [Line Items]
Non-controlling interests in loss of consolidated entities		$ (9,191)		$ (3,975)		$ (17,355)		$ (12,324)		$ (16,195)
Avenue [Member]
Noncontrolling Interest [Line Items]
Non-controlling interests in loss of consolidated entities		$ (1,015)	[1]	$ (47)		$ (1,329)		$ (231)		(349)
Non-controlling ownership		28.90%	[1]	10.50%	[2]	28.90%	[1]	10.50%	[2]
Coronado SO Co, Inc [Member]
Noncontrolling Interest [Line Items]
Non-controlling interests in loss of consolidated entities		$ (15)		$ (4)		$ (22)		$ (14)		(19)
Non-controlling ownership		13.00%		13.00%	[2]	13.00%		13.00%	[2]
Mustang Therapeutics, Inc [Member]
Noncontrolling Interest [Line Items]
Non-controlling interests in loss of consolidated entities		$ (3,241)	[1]	$ (204)		$ (8,268)		$ (363)		(1,805)
Non-controlling ownership		58.70%	[1]	10.00%	[2]	58.70%	[1]	10.00%	[2]
Checkpoint Therapeutics, Inc [Member]
Noncontrolling Interest [Line Items]
Non-controlling interests in loss of consolidated entities		$ (3,437)	[3]	$ (3,254)		$ (10,144)	[3]	$ (10,767)		(11,733)
Non-controlling ownership	[3]	61.90%		63.50%	[2]	61.90%		63.50%	[2]
JMC [Member]
Noncontrolling Interest [Line Items]
Non-controlling interests in loss of consolidated entities		$ (103)		$ (104)		$ (150)		$ (333)		(355)
Non-controlling ownership		6.90%		8.10%	[2]	6.90%		8.10%	[2]
Helocyte [Member]
Noncontrolling Interest [Line Items]
Non-controlling interests in loss of consolidated entities		$ (376)		$ (362)		$ (975)		$ (616)		(1,155)
Non-controlling ownership		20.00%		20.60%	[2]	20.00%		20.60%	[2]
Cellvation [Member]
Noncontrolling Interest [Line Items]
Non-controlling interests in loss of consolidated entities		$ 24				$ (60)				(158)
Non-controlling ownership		22.00%				22.00%
National Holdings [Member]
Noncontrolling Interest [Line Items]
Non-controlling interests in loss of consolidated entities		$ (27)				$ 4,845				$ (621)
Non-controlling ownership		43.40%				43.40%
Caelum [Member]
Noncontrolling Interest [Line Items]
Non-controlling interests in loss of consolidated entities		$ (835)				$ (1,086)
Non-controlling ownership		25.20%				25.20%
Aevitas [Member]
Noncontrolling Interest [Line Items]
Non-controlling interests in loss of consolidated entities		$ (166)				$ (166)
Non-controlling ownership		25.30%				25.30%

[1]	Mustang and Avenue are consolidated with Fortress’s operations because Fortress maintains voting control through its ownership of Mustang’s and Avenue’s Class A preferred shares which provide super-majority voting rights.
[2]	Represents a weighted average of ownership during the periods presented
[3]	Checkpoint is consolidated with Fortress’s operations because Fortress maintains voting control through its ownership of Checkpoint’s Class A common shares which provide for super-majority voting rights

Net Loss per Common Share - Com

Net Loss per Common Share - Computations of Diluted Weighted Average Shares Outstanding (Detail) - shares	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total of weighted average shares outstanding	13,063,630	13,767,873
Warrants to Purchase Common Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total of weighted average shares outstanding	678,072	480,559
Opus warrants to purchase Common Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total of weighted average shares outstanding	206,593	1,700,000
Options to Purchase Common Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total of weighted average shares outstanding	1,095,905	1,769,426
Unvested Restricted Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total of weighted average shares outstanding	9,848,505	8,763,797
Unvested Restricted Stock Units [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total of weighted average shares outstanding	1,234,555	1,054,091

Stockholders' Equity - Employee

Stockholders' Equity - Employee Stock Purchase Programs (Detail) - USD ($) $ in Thousands	3 Months Ended				9 Months Ended
	Sep. 30, 2017		Sep. 30, 2016		Sep. 30, 2017		Sep. 30, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 4,183		$ 2,903		$ 11,736		$ 8,792
Fortress Companies [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	2,510	[1]	963	[2]	6,506	[3]	3,293	[4]
Employee Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	1,650		1,937		5,170		5,490
Non-Employee Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 24		$ 3		$ 60		$ 9

[1]	Consists of approximately $0.2 million of Avenue's compensation expenses, approximately $0.9 million of Checkpoint's compensation expense, approximately $0.8 million of Mustang’s compensation expense, approximately $0.4 million of Caelum’s compensation expense, approximately $62,000 of JMC's compensation expenses, approximately $27,000 of Helocyte's compensation expenses and approximately $5,000 of Cellvation's compensation expenses on stock and option grants for the three months ended September 30, 2017.
[2]	Consists of approximately $5,000 of Avenue's compensation expenses, approximately $0.8 million of Checkpoint's compensation expense, approximately $130,000 of JMC's compensation expenses and approximately $67,000 of Helocyte's compensation expenses on stock grants for the three months ended September 30, 2016.
[3]	Consists of approximately $0.3 million of Avenue's compensation expenses, approximately $4.3 million of Checkpoint's compensation expense, approximately $1.2 million of Mustang’s compensation expense, approximately $0.4 million of Caelum’s compensation expense, approximately $0.2 million of JMC's compensation expenses, approximately $0.1 million of Helocyte's compensation expenses and approximately $19,000 of Cellvation's compensation expenses on stock and option grants for the nine months ended September 30, 2017.
[4]	Consists of approximately $23,000 of Avenue's compensation expenses, approximately $2.7 million of Checkpoint's compensation expense, approximately $458,000 of JMC's compensation expenses and approximately $160,000 of Helocyte's compensation expenses on stock grants for the nine months ended September 30, 2016.

Stockholders' Equity - Stock Op

Stockholders' Equity - Stock Option Activity (Detail) - USD ($) $ / shares in Units, $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2017	Dec. 31, 2016
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares, Options exercised	(20,000)
Weighted Average Exercise Price, Options expired	$ 1.37
Total Weighted Average Intrinsic Value, Options vested and exercisable	$ 1,620,046
Number of shares, Options vested and expected to vest	1,130,501
Number of shares, Options vested and expected to vest	1,100,501	1,130,501
Number of shares, Options vested and exercisable	1,085,501
Weighted average exercise price, Options vested and expected to vest	$ 3.73
Weighted average exercise price, Options vested and expected to vest	3.78	$ 3.73
Weighted average exercise price, Options vested and exercisable	$ 3.75
Total Weighted average intrinsic value, Options vested and expected to vest	$ 602,451
Total Weighted average intrinsic value, Options vested and expected to vest	$ 1,620,046	$ 602,451
Weighted average remaining contractual life (years), Options vested and expected to vest	4 years 2 months 16 days	4 years 11 months 5 days
Weighted average remaining contractual life (years), Options vested and exercisable	4 years 2 months 5 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value	$ 61,000

Stockholders' Equity - Restrict

Stockholders' Equity - Restricted Stock Activity (Detail) - Restricted Stock [Member]	9 Months Ended
	Sep. 30, 2017$ / sharesshares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares, Unvested balance \| shares	10,094,095
Number of shares, Restricted stock granted \| shares	1,325,396
Number of shares, Restricted stock vested \| shares	(213,333)
Number of shares, Restricted stock units granted \| shares	930,000
Number of shares, Restricted stock units forfeited \| shares	(15,000)
Number of shares, Restricted stock units vested \| shares	(214,625)
Number of shares, Unvested balance \| shares	11,906,533
Weighted average grant price, Unvested balance \| $ / shares	$ 2.49
Weighted average grant price, Restricted stock granted \| $ / shares	2.70
Weighted average grant price, Restricted stock vested \| $ / shares	2.75
Weighted average grant price, Restricted stock units granted \| $ / shares	4.31
Weighted average grant price, Restricted stock units forfeited \| $ / shares	2.98
Weighted average grant price, Restricted stock units vested \| $ / shares	3.44
Weighted average grant price, Unvested balance \| $ / shares	$ 2.63

Stockholders' Equity - Summariz

Stockholders' Equity - Summarizes Fortress warrant activities (Detail) - USD ($) $ / shares in Units, $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2017	Dec. 31, 2016
Subsidiary or Equity Method Investee [Line Items]
Weighted average remaining contractual life, Forfeited (years)	0 years
Warrant [Member]
Subsidiary or Equity Method Investee [Line Items]
Number of shares, Outstanding	2,263,453
Number of shares, Granted	816,180
Forfeited	(230,444)
Number of shares, Outstanding	2,849,189	2,263,453
Number of shares, Exercisable	869,189
Weighted average exercise price, Outstanding	$ 3.62
Weighted average exercise price, Granted	1.33
Weighted average exercise price, Forfeited	8.39
Weighted average exercise price, Outstanding	$ 2.57	$ 3.62
Total weighted average intrinsic value, Outstanding	$ 3,358,161	$ 79,800
Weighted average exercise price, Exercisable	$ 3.96
Total weighted average intrinsic value, Outstanding	$ 79,800
Total weighted average intrinsic value, Granted	329,954
Total weighted average intrinsic value, Forfeited	0
Total weighted average intrinsic value, Exercisable	$ 546,561
Weighted average remaining contractual life, Granted (years)	4 years 10 months 13 days
Weighted average remaining contractual life (years), Outstanding	4 years 8 months 8 days	4 years 8 months 26 days
Weighted average remaining contractual life, Exercisable (years)	4 years 3 months 18 days

Stockholders' Equity - Fair val

Stockholders' Equity - Fair value of options (Detail)	9 Months Ended
Stockholders' Equity - Fair value of options (Detail)	Sep. 30, 2017
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Risk-free interest rate, Minimum	1.88%
Risk-free interest rate, Maximum	2.22%
Expected dividend yield	0.00%
Expected volatility, Maximum	107.00%
Minimum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term in years	5 years
Maximum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term in years	7 years

Stockholders_ Equity - Monte Ca

Stockholders’ Equity - Monte Carlo simulation valuation methodology (Detail)	9 Months Ended
	Sep. 30, 2017
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate	0.00%
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term	7 years
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term	5 years
Mustang Bio, Inc [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate	0.00%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate	77.30%
Mustang Bio, Inc [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate	2.38%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term	10 years
Mustang Bio, Inc [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate	1.81%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term	5 years 6 months

Stockholders_ Equity - Mustang

Stockholders’ Equity - Mustang Bio stock option activities (Detail)	9 Months Ended
	Sep. 30, 2017$ / sharesshares
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Number	1,085,501
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested Granted, Weighted Average Remaining Contractual Term	9 years 6 months 22 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested Outstanding, Weighted Average Remaining Contractual Term	9 years 6 months 22 days
Mustang Bio, Inc [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Number of Shares	0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross	1,241,675
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Number of Shares	1,241,675
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Number	0
Sharebased Compensation Arrangement By Sharebased Payment Award Options Nonvested Granted, Weighted Average Price \| $ / shares	$ 5.73
Sharebased Compensation Arrangement By Sharebased Payment Award Options Nonvested Outstanding , Weighted Average Price \| $ / shares	$ 5.73

Stockholders' Equity - Addition

Stockholders' Equity - Additional Information (Detail) - USD ($)	Aug. 03, 2017	Apr. 07, 2017	Sep. 09, 2016	Jun. 26, 2017	Mar. 31, 2017	Mar. 17, 2017	Jan. 31, 2017	Jan. 31, 2016	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Employee Stock Purchase Plan to eligible employees, compensation expense recognized									$ 52,000	$ 35,000	$ 100,000	$ 91,000
General and Administrative Expense									12,318,000	7,620,000	28,827,000	21,202,000
Class of Warrant or Right, Exercise Price of Warrants or Rights				$ 4.02
Share-based Compensation											12,048,000	8,792,000
Warrants Issued					6,400		853,677
Stock Issued During Period, Value, Employee Stock Purchase Plan											$ 42,000
NSC 2017 Note [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Class of Warrant or Right, Exercise Price of Warrants or Rights					$ 3.70
Percentage Of Placement Agent Fee						10.00%					10.00%
Private Placement [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage Of Placement Agent Fee					10.00%
Payments of Stock Issuance Costs					$ 42,000,000
Percentage Of Shares Issued To Placement Agent					0.00%
IPO [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock Issued During Period, Shares, New Issues				6,325,000
Over-Allotment Option [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock Issued During Period, Shares, New Issues				825,000
Longterm Incentive Program [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value											$ 1,500,000		$ 1,400,000
Capital Units, Authorized							100,000,000
Share-based Compensation									$ 52,000	0	$ 52,000	0
Maximum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Class of Warrant or Right, Exercise Price of Warrants or Rights									$ 4.75		$ 4.75
Checkpoint [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Allocated Share-based Compensation Expense									$ 900,000	800,000	$ 4,300,000
Dr. Rosenwald [Member] \| Longterm Incentive Program [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period							552,698	510,434
Mustang [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock Based compensation, authorized number of shares							8,536,774
Allocated Share-based Compensation Expense									$ 800,000		$ 1,200,000
Mustang [Member] \| Private Placement [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Class of Warrant or Right, Exercise Price of Warrants or Rights									$ 8.50		$ 8.50
Stock Issued During Period, Value of Warrants Exercised											$ 65,000
Caelum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Allocated Share-based Compensation Expense									$ 400,000		400,000
Avenue Therapeutics, Inc. [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Research And Development Expense									200,000	3,000,000	200,000	12,000,000
General and Administrative Expense									78,000,000	3,000,000	90,000,000	12,000,000
Allocated Share-based Compensation Expense									$ 200,000	5,000	$ 300,000	23,000
Shares Issued, Price Per Share				$ 6
Mustang Bio, Inc [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock Based compensation, shares available for issuance									215,269		215,269
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Share-based Awards Other than Options									$ 2,300,000		$ 2,300,000
Share Price		$ 5.73
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross		200,000
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price											$ 5.73
Aggregate Number of Shares of Common Stock,Percentage											2.50%
Stock Issuance Costs											$ 1,200,000
Share-based Compensation Arrangement by Share-based Payment Award, Description											Both grants have the following vesting schedule: 50% of the options vest over-time with 25% vesting over 12 months of continued service, with the remaining 25% vesting in 12 equal installments thereafter, subject to continued employment. The remaining 50% vest and become exercisable upon the occurrence of the following milestones being achieved: (i) 25% of the grant vest upon the dosing of the first patient in the first Phase 2 clinical trial of any Mustang product candidate, (ii) 25% of the grant vest upon the dosing of the first patient in the first Phase 2 clinical trial of a second Mustang product candidate, (iii) 25% of the grant vest upon Mustangs achievement of a fully-diluted market capitalization of $500,000,000 and (iv) 25% of the grant vest upon Mustangs achievement of a fully-diluted market capitalization of $1,000,000,000.
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term											1 year 7 months 10 days
Mustang Bio, Inc [Member] \| NSC 2017 Note [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage Of Placement Agent Fee	10.00%
Warrants Issued	1,000
Mustang Bio, Inc [Member] \| Private Placement [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock Issued During Period, Shares, Issued for Services	10,000										2,500
Proceeds from Issuance of Private Placement	$ 65,000,000
Warrants Issued	2,500
Mustang Bio, Inc [Member] \| Chief Executive Officer [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross		1,041,675
Mustang Bio, Inc [Member] \| Employee [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price		$ 5.73
Journey Medical Corporation [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Allocated Share-based Compensation Expense										130,000	$ 200,000
Journey Medical Corporation [Member] \| Employee [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Net of Forfeitures											395,000,000
Checkpoint Therapeutics, Inc [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Allocated Share-based Compensation Expense												2,700,000
Share-based Compensation									400,000	400,000	$ 2,800,000	1,600,000
JMC [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Allocated Share-based Compensation Expense									62,000			458,000
Helocyte Inc [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Allocated Share-based Compensation Expense									27,000	67,000	100,000	160,000
Helocyte Inc [Member] \| Non-employee [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based Compensation									20,000	50,000		100,000
Cellvation Inc [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Allocated Share-based Compensation Expense									5,000		19,000
Cellvation Inc [Member] \| Non-employee [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based Compensation									$ 2,000		$ 7,000
National Holdings Corporation [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Class of Warrant or Right, Exercise Price of Warrants or Rights									$ 3.25		$ 3.25
National Holdings Corporation [Member] \| Private Placement [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage Of Placement Agent Fee			10.00%
Proceeds from Issuance of Private Placement					$ 400		$ 55,500,000
Warrants Issued							2,134,193
Private Placement Stock Units Shares To Be Issued									10,000		10,000
Percentage Of Shares Issued To Placement Agent							10.00%
National Holdings Corporation [Member] \| Mustang Bio, Inc [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock Based compensation, authorized number of shares					64,000
Payments of Stock Issuance Costs											$ 5,500,000
National Holdings Corporation [Member] \| Mustang Bio, Inc [Member] \| Private Placement [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Class of Warrant or Right, Outstanding					16,000
Common Stock [Member] \| Avenue Therapeutics, Inc. [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Proceeds from issuance of Common stock				$ 34,200,000
Stockholders' Equity, Reverse Stock Split				3-For-1
Research and Development Expense [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Allocated Share-based Compensation Expense									$ 1,600,000	900,000	4,800,000	3,400,000
General and Administrative Expense [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Allocated Share-based Compensation Expense									2,600,000	2,000,000	6,900,000	5,400,000
General and Administrative Expense [Member] \| Longterm Incentive Program [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based Compensation									200,000	75,000	500,000	200,000
General and Administrative Expense [Member] \| Helocyte Inc [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based Compensation									7,000	17,000	25,000	42,000
General and Administrative Expense [Member] \| Cellvation Inc [Member] \| Chief Executive Officer [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based Compensation									3,000		$ 11,000
Restricted Stock [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition											2 years
Share-based Compensation									700,000	200,000	$ 1,700,000	5,600,000
Restricted Stock [Member] \| Journey Medical Corporation [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based Compensation									95,000		25,000
Restricted Stock [Member] \| Checkpoint Therapeutics, Inc [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based Compensation									$ 500,000	$ 300,000	$ 1,500,000	$ 1,000,000
Restricted Stock Units (RSUs) [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition											2 years 2 months 12 days
Share-based Compensation											$ 5,600,000
Employee Stock Option [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common Stock issued in connection with the first ESPP offering											22,000
Common Stock, Capital Shares Reserved for Future Issuance									205,000		205,000
Stock Issued During Period, Value, Employee Stock Purchase Plan											$ 41,900
Employee Stock Option [Member] \| Maximum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common Stock issued in connection with the first ESPP offering											199,995
Employee Stock Option [Member] \| Journey Medical Corporation [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based Compensation									$ 8,000		$ 29,000

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Detail) $ in Millions	9 Months Ended
	Sep. 30, 2017USD ($)shares
Operating Leased Assets [Line Items]
Litigation Settlement, Expense	$ 2
Litigation Settlement, Amount Awarded to Other Party	$ 0.2
Mustang Common Shares [Member]
Operating Leased Assets [Line Items]
Number of Shares To Be Issued Upon Legal Settlement \| shares	200,000

Related Party Transactions - Sc

Related Party Transactions - Schedule of Effective Date and Equity Fee Payble (Detail)	9 Months Ended
	Sep. 30, 2017
Helocyte Inc [Member]
Dividends, Paid-in-kind,Percentage	2.50%
Dividends Payable, Date Declared	Mar. 20, 2015	[1]
Avenue Therapeutics, Inc. [Member]
Dividends, Paid-in-kind,Percentage	2.50%
Dividends Payable, Date Declared	Feb. 17, 2015	[1]
Mustang Bio, Inc [Member]
Dividends, Paid-in-kind,Percentage	2.50%
Dividends Payable, Date Declared	Mar. 13, 2015	[1]
Checkpoint Therapeutics, Inc [Member]
Dividends, Paid-in-kind,Percentage	0.00%	[2]
Dividends Payable, Date Declared	Mar. 17, 2015	[1]
Cellvation Inc [Member]
Dividends, Paid-in-kind,Percentage	2.50%
Dividends Payable, Date Declared	Oct. 31, 2016	[1]
Caelum Biosciences, Inc. [Member]
Dividends, Paid-in-kind,Percentage	2.50%
Dividends Payable, Date Declared	Jan. 1, 2017	[1]
Cyprium Biosciences, Inc [Member]
Dividends, Paid-in-kind,Percentage	2.50%
Dividends Payable, Date Declared	Mar. 13, 2017	[1]
Aevitas Inc [Member]
Dividends, Paid-in-kind,Percentage	2.50%
Dividends Payable, Date Declared	Jul. 28, 2017	[1]

[1]	Represents the effective date of each subsidiary’s Founders Agreement. Each PIK dividend and equity fee is payable on the annual anniversary of the effective date of the original Founders Agreement.
[2]	Instead of a PIK dividend, Checkpoint pays the Company an annual equity fee in shares of Checkpoint’s common stock equal to 2.5% of Checkpoint’s fully diluted outstanding capitalization.

Related Party Transactions - 78

Related Party Transactions - Schedule of The Effective Date and Annual Management Services agreement Fee (Income) Expense (Detail) $ in Thousands	9 Months Ended
	Sep. 30, 2017USD ($)
Annual Management Services Agreement Fee Income Expense	$ 0
Research and Development Expense [Member]
Annual Management Services Agreement Fee Income Expense	0
Selling, General and Administrative Expenses [Member]
Annual Management Services Agreement Fee Income Expense	0
Helocyte Inc [Member]
Annual Management Services Agreement Fee Income Expense	$ 500
Annual Consulting Fee Payable Effective Date	Mar. 20, 2015
Helocyte Inc [Member] \| Research and Development Expense [Member]
Annual Management Services Agreement Fee Income Expense	$ 250
Helocyte Inc [Member] \| Selling, General and Administrative Expenses [Member]
Annual Management Services Agreement Fee Income Expense	250
Avenue Therapeutics, Inc. [Member]
Annual Management Services Agreement Fee Income Expense	$ 500
Annual Consulting Fee Payable Effective Date	Feb. 17, 2015
Avenue Therapeutics, Inc. [Member] \| Research and Development Expense [Member]
Annual Management Services Agreement Fee Income Expense	$ 250
Avenue Therapeutics, Inc. [Member] \| Selling, General and Administrative Expenses [Member]
Annual Management Services Agreement Fee Income Expense	250
Mustang Bio, Inc [Member]
Annual Management Services Agreement Fee Income Expense	$ 500
Annual Consulting Fee Payable Effective Date	Mar. 13, 2015
Mustang Bio, Inc [Member] \| Research and Development Expense [Member]
Annual Management Services Agreement Fee Income Expense	$ 250
Mustang Bio, Inc [Member] \| Selling, General and Administrative Expenses [Member]
Annual Management Services Agreement Fee Income Expense	250
Checkpoint Therapeutics, Inc [Member]
Annual Management Services Agreement Fee Income Expense	$ 500
Annual Consulting Fee Payable Effective Date	Mar. 17, 2015
Checkpoint Therapeutics, Inc [Member] \| Research and Development Expense [Member]
Annual Management Services Agreement Fee Income Expense	$ 250
Checkpoint Therapeutics, Inc [Member] \| Selling, General and Administrative Expenses [Member]
Annual Management Services Agreement Fee Income Expense	250
Cellvation Inc [Member]
Annual Management Services Agreement Fee Income Expense	$ 500
Annual Consulting Fee Payable Effective Date	Oct. 31, 2016
Cellvation Inc [Member] \| Research and Development Expense [Member]
Annual Management Services Agreement Fee Income Expense	$ 250
Cellvation Inc [Member] \| Selling, General and Administrative Expenses [Member]
Annual Management Services Agreement Fee Income Expense	250
Caelum Biosciences, Inc. [Member]
Annual Management Services Agreement Fee Income Expense	$ 500
Annual Consulting Fee Payable Effective Date	Jan. 1, 2017
Caelum Biosciences, Inc. [Member] \| Research and Development Expense [Member]
Annual Management Services Agreement Fee Income Expense	$ 250
Caelum Biosciences, Inc. [Member] \| Selling, General and Administrative Expenses [Member]
Annual Management Services Agreement Fee Income Expense	250
Cyprium Biosciences, Inc [Member]
Annual Management Services Agreement Fee Income Expense	$ 500
Annual Consulting Fee Payable Effective Date	Mar. 13, 2017
Cyprium Biosciences, Inc [Member] \| Research and Development Expense [Member]
Annual Management Services Agreement Fee Income Expense	$ 250
Cyprium Biosciences, Inc [Member] \| Selling, General and Administrative Expenses [Member]
Annual Management Services Agreement Fee Income Expense	250
Fortress Biotech Inc [Member]
Annual Management Services Agreement Fee Income Expense	(4,000)
Fortress Biotech Inc [Member] \| Research and Development Expense [Member]
Annual Management Services Agreement Fee Income Expense	(2,000)
Fortress Biotech Inc [Member] \| Selling, General and Administrative Expenses [Member]
Annual Management Services Agreement Fee Income Expense	(2,000)
Aevitas Inc [Member]
Annual Management Services Agreement Fee Income Expense	$ 500
Annual Consulting Fee Payable Effective Date	Jul. 28, 2017
Aevitas Inc [Member] \| Research and Development Expense [Member]
Annual Management Services Agreement Fee Income Expense	$ 250
Aevitas Inc [Member] \| Selling, General and Administrative Expenses [Member]
Annual Management Services Agreement Fee Income Expense	$ 250

Related Party Transactions - Ad

Related Party Transactions - Additional Information (Detail) - USD ($)	1 Months Ended					3 Months Ended		9 Months Ended
	Jul. 31, 2017	Jun. 30, 2017	Jun. 26, 2017	Mar. 17, 2017	May 31, 2015	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Mar. 31, 2017	Sep. 09, 2016	Mar. 17, 2014
Related Party Transaction [Line Items]
Lease Sharing Agreements Contributions To Property Under Lease								$ 300,000
Equity Method Investment, Ownership Percentage												35.00%
Class of Warrant or Right, Exercise Price of Warrants or Rights			$ 4.02
Proceeds From Convertible Debt								9,914,000	$ 3,018,000
Payments of Financing Costs								$ 1,081,000	0
Avenue Therapeutics, Inc. [Member]
Related Party Transaction [Line Items]
Payments for Underwriter Fees			$ 2,300,000
Maximum [Member]
Related Party Transaction [Line Items]
Class of Warrant or Right, Exercise Price of Warrants or Rights						$ 4.75		$ 4.75
Minimum [Member]
Related Party Transaction [Line Items]
Class of Warrant or Right, Exercise Price of Warrants or Rights						$ 3.61		$ 3.61
National Holdings Corporation [Member]
Related Party Transaction [Line Items]
Business Acquisition, Percentage of Voting Interests Acquired				56.60%		56.60%		56.60%			56.60%
NSC Note [Member]
Related Party Transaction [Line Items]
Payments for Rent						$ 900,000		$ 2,800,000
NSC 2017 Note [Member]
Related Party Transaction [Line Items]
Debt Instrument, Face Amount										$ 3,250,000
Percentage Of Placement Agent Fee				10.00%				10.00%
Warrant On Sale Price Of Note Percentage				10.00%		10.00%		10.00%
Class of Warrant or Right, Number of Securities Called by Warrants or Rights						716,180		716,180
Class of Warrant or Right, Exercise Price of Warrants or Rights										$ 3.70
NSC 2017 Note [Member] \| Maximum [Member]
Related Party Transaction [Line Items]
Debt Instrument, Face Amount										$ 40,000,000
Caelum Convertible Notes [Member]
Related Party Transaction [Line Items]
Debt Instrument, Face Amount	$ 10,000,000
Proceeds From Convertible Debt	9,900,000					$ 9,900,000
Payments of Financing Costs	$ 900,000					$ 900,000
Debt Instrument Issuance, Percentage of Commission	10.00%
Class of Warrant or Right, Percentage Securities Called by Warrants or Rights	10.00%					10.00%
Class of Warrant or Right, Exercise Price percentage	110.00%					110.00%
Class of Warrant or Right, Exercise Price Description								the exercise price will be $75 million dollars divided by the total number of fully-diluted shares of Common Stock outstanding immediately prior to exercise of the warrant, giving effect to the assumed conversion of all options, warrants, and convertible securities of the Company
Opus Credit Facility [Member]
Related Party Transaction [Line Items]
Payments of Loan Costs						$ 300,000	$ 800,000	$ 0	0
Chord Advisors, LLC [Member]
Related Party Transaction [Line Items]
Related Party Transaction, Expenses from Transactions with Related Party					$ 10,000
Board of Directors Chairman [Member] \| National Holdings Corporation [Member]
Related Party Transaction [Line Items]
Equity Method Investment, Ownership Percentage						4.60%		4.60%
TG Therapeutics, Inc [Member]
Related Party Transaction [Line Items]
Payments for Rent								$ 600,000
Due from Related Parties, Current						$ 100,000		100,000
Checkpoint [Member] \| Chord Advisors, LLC [Member]
Related Party Transaction [Line Items]
Related Party Transaction, Expenses from Transactions with Related Party						$ 15,000		52,000
Founders Agreement [Member] \| Avenue Therapeutics, Inc. [Member]
Related Party Transaction [Line Items]
Other Fee,Percentage		2.50%	2.50%
Founders Agreement [Member] \| Caelum Convertible Notes [Member]
Related Party Transaction [Line Items]
Other Fee,Percentage						2.50%
Stock Issued During Period, Shares, Conversion of Convertible Securities						218,000
Stock Issued During Period, Value, Conversion of Convertible Securities						$ 200,000
OPPM [Member]
Related Party Transaction [Line Items]
Payments for Rent								100,000
Due from Related Parties, Current						28,000		28,000
Mustang [Member] \| Chord Advisors, LLC [Member]
Related Party Transaction [Line Items]
Related Party Transaction, Expenses from Transactions with Related Party					7,500
Avenue [Member] \| Chord Advisors, LLC [Member]
Related Party Transaction [Line Items]
Related Party Transaction, Expenses from Transactions with Related Party					$ 5,000	17,000		58,000
Avenue [Member] \| Founders Agreement [Member]
Related Party Transaction [Line Items]
Stock Issued During Period, Shares, New Issues			158,000
Desk Share Agreements [Member]
Related Party Transaction [Line Items]
Payments for Rent								1,800,000
Desk Share Agreements [Member] \| TG Therapeutics, Inc [Member]
Related Party Transaction [Line Items]
Due from Related Parties, Current						56,000		56,000
Desk Share Agreements [Member] \| OPPM [Member]
Related Party Transaction [Line Items]
Due from Related Parties, Current						100,000		100,000
Shared Services Agreement [Member] \| TG Therapeutics, Inc [Member]
Related Party Transaction [Line Items]
Proceeds from Related Party Agreement						200,000	$ 300,000	800,000	$ 600,000
Due from Related Parties, Current						$ 100,000		$ 100,000

Net Capital Requirements of B80

Net Capital Requirements of Broker-Dealer Subsidiaries - Additional Information (Detail)	Jun. 30, 2017USD ($)
Minimum [Member]
Ratio of Indebtedness to Net Capital	1
Maximum [Member]
Ratio of Indebtedness to Net Capital	15
National Securities [Member]
Net Capital	$ 10,500,000
Excess Net Capital at 1000 Percent	10,200,000
Minimum Net Capital Required for Broker-Dealer Subsidiary	250,000
Vfinance Investments [Member]
Net Capital	1,500,000
Excess Net Capital at 1000 Percent	500,000
Minimum Net Capital Required for Broker-Dealer Subsidiary	$ 1,000,000
Vfinance Investments [Member] \| Minimum [Member]
Ratio of Indebtedness to Net Capital	0.8
Vfinance Investments [Member] \| Maximum [Member]
Ratio of Indebtedness to Net Capital	1

Segment Information - Operating

Segment Information - Operating Results by Reportable Segment (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Segment Reporting Information [Line Items]
Net Revenue	$ 46,886	$ 975	$ 142,265	$ 3,865
Direct cost of goods	(505)	(41)	(1,852)	(365)
Sales and marketing costs	(2,786)	(1,244)	(7,663)	(4,212)
Research and development	(16,190)	(8,316)	(38,077)	(24,559)
General and administrative	(12,318)	(7,620)	(28,827)	(21,202)
National Expenses	79,489	17,221	215,638	50,338
Segment loss from operations	(32,603)	(16,246)	(73,373)	(46,473)
Segment assets	245,091	145,421	245,091	145,421	$ 170,731
Dermatology Products Sales [Member]
Segment Reporting Information [Line Items]
Net Revenue	2,170	429	8,309	1,793
Direct cost of goods	(505)	(41)	(1,852)	(365)
Sales and marketing costs	(2,786)	(1,244)	(7,663)	(4,212)
Research and development		0		0
General and administrative	(349)	(422)	(961)	(1,338)
National Expenses	0		0
Segment loss from operations	(1,470)	(1,278)	(2,167)	(4,122)
Segment assets	7,362	2,657	7,362	2,657
Pharmaceutical And Biotechnology Product Development [Member]
Segment Reporting Information [Line Items]
Net Revenue	350	546	1,393	2,072
Direct cost of goods	0	0	0	0
Sales and marketing costs	0	0	0	0
Research and development	(16,190)	(8,316)	(38,077)	(24,559)
General and administrative	(11,969)	(7,198)	(27,866)	(19,864)
National Expenses	0		0
Segment loss from operations	(27,809)	(14,968)	(64,550)	(42,351)
Segment assets	160,038	103,225	160,038	103,225
National [Member]
Segment Reporting Information [Line Items]
Net Revenue	44,366	0	132,563	0
Direct cost of goods		0		0
Sales and marketing costs		0		0
Research and development		0		0
General and administrative		0		0
National Expenses	(47,690)		(139,219)
Segment loss from operations	(3,324)	0	(6,656)	0
Segment assets	$ 77,691	$ 39,539	$ 77,691	$ 39,539

Segment Information - Additiona

Segment Information - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Customer One [Member]
Segment Reporting Information [Line Items]
Sales Revenue, Goods, Gross	$ 3	$ 0.2	$ 6.7	$ 0.8
Accounts Receivable, Net	1.7		1.7		$ 1.1
Customer Two [Member]
Segment Reporting Information [Line Items]
Sales Revenue, Goods, Gross	1.7	$ 43	6	0.3
Accounts Receivable, Net	$ 1.5		$ 1.5		$ 0.5
Customer Three [Member]
Segment Reporting Information [Line Items]
Sales Revenue, Goods, Gross				$ 0.3

Subsequent Events - Additional

Subsequent Events - Additional Information (Detail) $ / shares in Units, $ in Thousands	Nov. 06, 2017USD ($)$ / sharesshares	Oct. 27, 2017USD ($)a	Jun. 26, 2017shares	Sep. 30, 2017USD ($)	Sep. 30, 2016USD ($)
Subsequent Event [Line Items]
Stock Issued During Period, Value, Issued for Services				$ 2	$ 2
Over-Allotment Option [Member]
Subsequent Event [Line Items]
Stock Issued During Period, Shares, New Issues \| shares			825,000
Subsequent Event [Member] \| Perpetual Preferred Offering [Member] \| Series A Preferred Stock [Member]
Subsequent Event [Line Items]
Stock Issued During Period, Shares, New Issues \| shares	1,000,000
Shares Issued, Price Per Share \| $ / shares	$ 25
Stock Issued During Period, Value, Issued for Services	$ 25,000
Preferred Stock, Dividend Rate, Percentage	9.375%
Subsequent Event [Member] \| Over-Allotment Option [Member] \| Series A Preferred Stock [Member]
Subsequent Event [Line Items]
Stock Issued During Period, Shares, Share-based Compensation, Gross \| shares	150,000
Subsequent Event [Member] \| Mustang [Member]
Subsequent Event [Line Items]
Land Subject to Ground Leases \| a		27,043
Operating Leases, Rent Expense, Sublease Rentals		$ 3,600
Land Improvements		3,500
Security Deposit		800
Increase (Decrease) in Security Deposits		1,300
Subsequent Event [Member] \| Mustang [Member] \| Cash [Member]
Subsequent Event [Line Items]
Security Deposit		300
Increase (Decrease) in Security Deposits		300
Subsequent Event [Member] \| Mustang [Member] \| Letter of Credit [Member]
Subsequent Event [Line Items]
Security Deposit		500
Increase (Decrease) in Security Deposits		$ 1,000

Sponsored Research Agreements	9 Months Ended
Sponsored Research Agreements	Sep. 30, 2017
Research and Development [Abstract]
Research, Development, and Computer Software Disclosure	9. Sponsored Research Agreements Checkpoint NeuPharma, Inc. Sponsored Research Agreement In connection with its license agreement with NeuPharma, Inc. (“NeuPharma”), Checkpoint entered into a Sponsored Research Agreement with NeuPharma for certain research and development activities. Effective January 11, 2016, TGTX, a related party, agreed to assume all costs associated with this Sponsored Research Agreement and paid Checkpoint for all amounts previously paid by the Company. For the three months ended September 30, 2017 and 2016, approximately $ 0.1 0.2 0.5 0.7 Helocyte PepVax and Triplex Clinical Research and Support Agreements In March 2016, Helocyte entered into an Investigator-Initiated Clinical Research Support Agreement, as amended, with the COH, to support a Phase 2 clinical study of its PepVax immunotherapy for CMV control in allogeneic stem cell transplant recipients (“PepVax Research Agreement”). The Phase 2 study is additionally supported by grants from the National Institutes of Health/National Cancer Institute. In February 2016, Helocyte entered into an Investigator-Initiated Clinical Research Support Agreement, as amended, with the COH, to support a Phase 2 clinical study of its Triplex immunotherapy for CMV control in allogeneic stem cell transplant recipients (“Triplex Research Agreement”). For the three months ended September 30, 2017 and 2016, Helocyte incurred expenses of $ 1.3 0.4 0.5 0.5 2.3 1.4 0.7 1.5 Pentamer Sponsored Research Agreement On May 1, 2017, Helocyte and COH entered in a Sponsored Research Agreement for preclinical studies in connection with the development of Pentatmer. In June 2017, Helocyte made an upfront payment of $ 1.5 12,000 24,000 Mustang In connection with Mustang’s license with COH for the development of CAR-T, Mustang entered into a Sponsored Research Agreement in which Mustang will fund continued research in the amount of $ 2.0 0.5 0.5 1.5 1.5 CD 123 Clinical Research Support Agreement On February 17, 2017, Mustang entered into a Clinical Research Support Agreement for CD123. Pursuant to the terms of this agreement Mustang made an upfront payment of approximately $ 20,000 0.1 0.2 IL13Rα2 Clinical Research Support Agreement Also on February 17, 2017, Mustang entered into a Clinical Research Support Agreement for IL13Rα2 (“IL13Rα2 CRA”). Pursuant to the terms of this agreement Mustang made an upfront payment of approximately $ 9,300 0.2 1.2 CD20 Clinical Trial Agreement Also, on July 3, 2017, in conjunction with the CD20 Technology License from Fred Hutch, Mustang entered into an investigator-initiated clinical trial agreement (“CD20 CTA”) to provide partial funding for a Phase 1/2 clinical trial at Fred Hutch evaluating the safety and efficacy of the CD20 Technology in patients with relapsed or refractory B-cell non-Hodgkin lymphomas. In connection with the CD20 CTA, Mustang agreed to fund up to $ 5.3 88,000 0.4

Fortress Biotech (FBIO) 10-Q9 Nov 172017 Q3 Quarterly reportFinancial data

Document And Entity Information

Condensed Consolidated Balance

Condensed Consolidated Balance3

Condensed Consolidated Statemen

Condensed Consolidated Stateme5

Condensed Consolidated Stateme6

Organization and Description of

Summary of Significant Accounti

National Holdings Corporation A

Broker-Dealers and Clearing Org

Forgivable Loans Receivable

Property and Equipment

Fair Value Measurements

Licenses Acquired

Sponsored Research Agreements

Intangibles, net

Debt and Interest

Accrued Expenses and Other Long

Non-Controlling Interests

Net Loss per Common Share

Stockholders' Equity

Commitments and Contingencies

Related Party Transactions

Net Capital Requirements of Bro

Off Balance Sheet Risk and Conc

Segment Information

Subsequent Events

Summary of Significant Accoun28

National Holdings Corporation29

Property and Equipment (Tables)

Fair Value Measurements (Tables

Licenses Acquired (Tables)

Debt and Interest (Tables)

Accrued Expenses and Other Lo34

Non-Controlling Interests (Tabl

Net Loss per Common Share (Tabl

Stockholders' Equity (Tables)

Related Party Transactions (Tab

Segment Information (Tables)

Summary of Significant Accoun40

National Holdings Corporation41

National Holdings Corporation42

National Holdings Corporation43

National Holdings Corporation44

Broker-Dealers and Clearing O45

Forgivable Loans Receivable - A

Property and Equipment - Compon

Property and Equipment - Schedu

Property and Equipment - Additi

Fair Value Measurements - Warra

Fair Value Measurements - Deriv

Fair Value Measurements - Natio

Fair Value Measurements - Chang

Fair Value Measurements - Addit

Licenses Acquired - Summary Of

Licenses Acquired - Additional

Sponsored Research Agreements -

Intangibles, net - Additional I

Debt and Interest - Long-term d

Debt and Interest - Schedule of

Debt and Interest- Additional I

Accrued Expenses and Other Lo62

Accrued Expenses and Other Lo63

Accrued Expenses and Other Lo64

Non-Controlling Interests - Sum

Non-Controlling Interests - S66

Net Loss per Common Share - Com

Stockholders' Equity - Employee

Stockholders' Equity - Stock Op

Stockholders' Equity - Restrict

Stockholders' Equity - Summariz

Stockholders' Equity - Fair val

Stockholders_ Equity - Monte Ca

Stockholders_ Equity - Mustang

Stockholders' Equity - Addition

Commitments and Contingencies -

Related Party Transactions - Sc

Related Party Transactions - 78

Related Party Transactions - Ad