Immunomedics (IMMU) 10-K 27 Feb 20 2019 FY Annual report Financial data

COVER PAGE

COVER PAGE - USD ($)	12 Months Ended
	Dec. 31, 2019	Feb. 21, 2020	Jun. 30, 2019
Cover page.
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2019
Document Transition Report	false
Entity File Number	0-12104
Entity Registrant Name	IMMUNOMEDICS, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	61-1009366
Entity Address, Address Line One	300 The American Road
Entity Address, City or Town	Morris Plains,
Entity Address, State or Province	NJ
Entity Address, Postal Zip Code	07950
City Area Code	973
Local Phone Number	605-8200
Title of 12(b) Security	Common Stock, $0.01 par value
Trading Symbol	IMMU
Security Exchange Name	NASDAQ
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Shell Company	false
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Public Float			$ 2,660,996,949
Entity Common Stock, Shares Outstanding		213,929,505
Documents Incorporated by Reference	Specified portions of the registrant’s proxy statement, which will be filed with the Commission pursuant to Regulation 14A within 120 days of the end of the fiscal year ended December 31, 2019 in connection with the registrant’s 2020 Annual Meeting of Stockholders, are incorporated by reference into Part III of this annual report on Form 10-K.
Entity Central Index Key	0000722830
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	FY
Amendment Flag	false

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Current Assets:
Cash and cash equivalents	$ 608,628	$ 492,860
Marketable securities	4,550	4,941
Accounts receivable, net of allowances of $0 at December 31, 2019	295	0
Prepaid expenses	21,818	5,354
Other current assets	3,413	1,348
Total current assets	638,704	504,503
Property and equipment, net of accumulated depreciation and amortization of $7,925 and $4,316 at December 31, 2019 and 2018, respectively	32,762	23,469
Other long-term assets	256	68
Total Assets	671,722	528,040
Current Liabilities:
Accounts payable and accrued expenses	60,860	31,722
Liability related to sale of future royalties - current	3,455	0
Lease liability - current	337
Convertible senior notes, net	7,106	0
Total current liabilities	71,758	31,722
Convertible senior notes, net	0	7,055
Liability related to sale of future royalties - non-current	257,769	221,295
Deferred revenues	65,000	0
Other long-term liabilities	9,965	2,119
Total Liabilities	404,492	262,191
Commitments and Contingencies (Note 14)
Stockholders' Equity:
Convertible preferred stock, $0.01 par value; authorized 10,000,000 shares; no shares issued and outstanding at December 31, 2019 and 2018	0	0
Common stock, $0.01 par value; authorized 250,000,000 shares; issued 212,529,313 shares and outstanding 212,409,692 shares at December 31, 2019; issued 190,445,795 shares and outstanding 190,411,070 shares at December 31, 2018	2,125	1,905
Capital contributed in excess of par	1,579,205	1,219,237
Treasury stock, at cost: 119,621 shares at December 31, 2019 and 34,725 shares at December 31, 2018	(2,095)	(824)
Accumulated deficit	(1,310,406)	(953,216)
Accumulated other comprehensive loss	(568)	(351)
Total Immunomedics, Inc. stockholders' equity	268,261	266,751
Noncontrolling interest in subsidiary	(1,031)	(902)
Total Stockholders' Equity	267,230	265,849
Total Liabilities and Stockholders' Equity	$ 671,722	$ 528,040

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Allowances for doubtful accounts	$ 0
Accumulated depreciation	$ 7,925
Accumulated depreciation		$ 4,316
Preferred stock, par value (in USD per share)	$ 0.01
Preferred stock, shares authorized (in shares)	10,000,000
Common stock, par value (in USD per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	250,000,000	250,000,000
Common stock, shares issued (in shares)	212,529,313	190,445,795
Common stock, shares outstanding (in shares)	212,409,692	190,411,070
Treasury stock, shares (in shares)	119,621	34,725
Convertible preferred stock
Preferred stock, par value (in USD per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized (in shares)	10,000,000	10,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0

CONSOLIDATED STATEMENTS OF COMP

CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS - USD ($) shares in Thousands, $ in Thousands	6 Months Ended	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2019	Jun. 30, 2018	Jun. 30, 2017
Revenues	$ 0	$ 295	$ 2,156	$ 3,091
Costs and expenses:
Costs of goods sold	0	0	613	483
Research and development	93,887	254,871	99,283	51,776
Sales and marketing	19,834	26,459	6,822	873
General and administrative	30,814	43,803	36,485	29,109
Total costs and expenses	144,535	325,133	143,203	82,241
Operating loss	(144,535)	(324,838)	(141,047)	(79,150)
Changes in fair market value of warrant liabilities	1,404	0	(108,636)	(61,074)
Warrant related expenses	0	0	0	(7,649)
Interest expense	(20,017)	(40,337)	(23,255)	(5,480)
Interest and other income	6,106	7,856	5,493	431
Loss on induced exchanges of debt	(897)	0	(13,005)	0
Other financing expenses	0	0	0	(347)
Insurance reimbursement	190	0	6,638	0
Foreign currency transaction gain, net	0	0	81	23
Loss before income tax	(157,749)	(357,319)	(273,731)	(153,246)
Income tax expense	0	0	(156)	(20)
Net loss	(157,749)	(357,319)	(273,887)	(153,266)
Net loss attributable to noncontrolling interest	(81)	(129)	(50)	(60)
Net loss attributable to Immunomedics, Inc. stockholders	$ (157,668)	$ (357,190)	$ (273,837)	$ (153,206)
Loss per common share attributable to Immunomedics, Inc. stockholders (basic and diluted) (in USD per share)	$ (0.84)	$ (1.84)	$ (1.78)	$ (1.47)
Weighted average shares used to calculate loss per common share (basic and diluted) (in shares)	188,554	193,617	153,475	104,536
Other comprehensive (loss) income, net of tax:
Foreign currency translation adjustments	$ (8)	$ 174	$ (105)	$ (62)
Unrealized gain (loss) on securities available for sale	10	(391)	55	(109)
Other comprehensive income (loss), net of tax:	2	(217)	(50)	(171)
Comprehensive loss	(157,747)	(357,536)	(273,937)	(153,437)
Comprehensive loss attributable to noncontrolling interest	(81)	(129)	(50)	(60)
Comprehensive loss attributable to Immunomedics, Inc. stockholders	(157,666)	(357,407)	(273,887)	(153,377)
Product sales
Revenues	0	0	1,501	2,443
License fee and other revenues
Revenues	0	295	330	284
Research and development
Revenues	$ 0	$ 0	$ 325	$ 364

CONSOLIDATED STATEMENTS OF CHAN

CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS’ EQUITY - USD ($) $ in Thousands	Total	Rpi Finance Trust	Common Stock	Common StockRpi Finance Trust	Capital Contributed in Excess of Par	Capital Contributed in Excess of ParRpi Finance Trust	Treasury Stock	Treasury StockRpi Finance Trust	Accumulated Deficit	Accumulated Other Comprehensive (Loss) Income	Noncontrolling Interest	Convertible preferred stock	IPO	IPOCommon Stock	IPOCapital Contributed in Excess of Par	Private placementSeattle Genetics, Inc., (“SGEN”)	Private placementCommon StockSeattle Genetics, Inc., (“SGEN”)	Private placementCapital Contributed in Excess of ParSeattle Genetics, Inc., (“SGEN”)	Market Offering	Market OfferingCommon Stock	Market OfferingCapital Contributed in Excess of Par
Beginning balance (in shares) at Jun. 30, 2016			95,868,000									0
Beginning balance at Jun. 30, 2016	$ (57,528)		$ 958		$ 311,320		$ (458)		$ (368,505)	$ (132)	$ (711)	$ 0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of preferred stock (in shares)												1,000,000
Issuance of preferred stock, net	121,782				121,772							$ 10
Issuance of common stock (in shares)														10,000,000			3,000,000
Issuance of common stock, net													$ 28,578	$ 100	$ 28,478	$ 14,700	$ 30	$ 14,670
Proceeds of public offering allocated to warrant liability	(6,966)				(6,966)											$ (14,670)		$ (14,670)
Exercise of stock options (in shares)			1,279,000
Exercise of stock options, net	4,290		$ 13		4,277
Stock based compensation (in shares)			198,000
Stock-based compensation	3,787		$ 2		3,785
Other comprehensive income (loss)	(171)									(171)
Net loss	(153,266)								(153,206)		(60)
Ending balance (in shares) at Jun. 30, 2017			110,345,000									1,000,000
Ending balance at Jun. 30, 2017	(59,464)		$ 1,103		462,666		(458)		(521,711)	(303)	(771)	$ 10
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Reclassification of warrant liability to equity	190,369				190,369
Issuance of common stock (in shares)				4,373,000										13,225,000
Issuance of common stock, net		$ 67,784		$ 44		$ 67,740							299,467	$ 132	299,335
Exercise of common stock warrants (in shares)			18,206,000
Exercise of common stock warrants	78,226		$ 182		78,044
Exercise of stock options (in shares)			586,000
Exercise of stock options, net	2,261		$ 6		2,255
Conversion of preferred shares (in shares)			23,105,000									1,000,000
Conversion of preferred stock	0		$ 231		(221)							$ (10)
Issuance of common stock due to debt conversion (in shares)			16,800,000
Issuance of common stock due to debt conversion	92,475		$ 168		92,307
Stock based compensation (in shares)			331,000
Stock-based compensation	4,027		$ 3		4,024
Conversion of RSU's for tax withholding payments (in shares)			(170,000)
Conversion of RSU's for tax withholding payments	(1,522)		$ (1)		(1,521)
Other comprehensive income (loss)	(50)									(50)
Net loss	(273,887)								(273,837)		(50)
Ending balance (in shares) at Jun. 30, 2018			186,801,000									0
Ending balance at Jun. 30, 2018	399,686		$ 1,868		1,194,998		(458)		(795,548)	(353)	(821)	$ 0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Reclassification of warrant liability to equity	7,569				7,569
Exercise of common stock warrants (in shares)			450,000
Exercise of common stock warrants	1,688		$ 5		1,683
Exercise of stock options (in shares)			706,000
Exercise of stock options, net	$ 176		$ 7		2,619		(2,450)
Retirement of treasury stock (in shares)	(105,959)			(106,000)
Retirement of treasury stock		$ 0		$ (1)		$ (2,083)		$ 2,084
Issuance of common stock due to debt conversion (in shares)			2,568,000
Issuance of common stock due to debt conversion	$ 13,783		$ 26		13,757
Stock based compensation (in shares)			36,000
Stock-based compensation	886				886
Conversion of RSU's for tax withholding payments (in shares)			(9,000)
Conversion of RSU's for tax withholding payments	(192)				(192)
Other comprehensive income (loss)	2									2
Net loss	(157,749)								(157,668)		(81)
Ending balance (in shares) at Dec. 31, 2018			190,446,000									0
Ending balance at Dec. 31, 2018	265,849		$ 1,905		1,219,237		(824)		(953,216)	(351)	(902)	$ 0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock (in shares)														16,429,000						4,432,000
Issuance of common stock, net													$ 273,031	$ 164	$ 272,867				$ 71,597	$ 44	$ 71,553
Exercise of stock options (in shares)			1,207,000
Exercise of stock options, net	2,553		$ 12		3,812		(1,271)
Stock based compensation (in shares)			15,000
Stock-based compensation	11,736				11,736
Other comprehensive income (loss)	(217)									(217)
Net loss	(357,319)								(357,190)		(129)
Ending balance (in shares) at Dec. 31, 2019			212,529,000									0
Ending balance at Dec. 31, 2019	$ 267,230		$ 2,125		$ 1,579,205		$ (2,095)		$ (1,310,406)	$ (568)	$ (1,031)	$ 0

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2019	Jun. 30, 2018	Jun. 30, 2017
Cash flows from operating activities:
Net loss	$ (157,749)	$ (357,319)	$ (273,887)	$ (153,266)
Adjustments to reconcile net loss to net cash used in operating activities:
Changes in fair value of warrant liabilities	(1,404)	0	108,636	61,074
Warrant related expense	0	0	0	7,649
Depreciation and amortization	2,099	3,822	1,297	923
Loss on disposal of property and equipment	0	1,003	0	0
Interest on non-recourse debt	19,288	39,929	19,791	0
Loss on induced exchanges of debt	897	0	13,005	0
Amortization of deferred revenue	(94)	0	(77)	(64)
Amortization of bond premiums	3	0	31	218
Amortization of debt issuance costs	179	50	1,679	730
Amortization of deferred rent	132	0	279	10
Non-cash lease expense	0	264	0	0
Loss on sale of marketable securities	0	0	0	16
Decrease in allowance for doubtful accounts	0	0	(9)	(62)
Non-cash expense related to stock-based compensation	886	11,736	4,024	4,333
Non-cash financing expenses	0	0	0	347
Changes in operating assets and liabilities
Accounts receivable, net	46	(295)	452	103
Inventories, net	0	0	580	(196)
Other receivables	0	0	(30)	223
Prepaid expenses and other current assets	3,617	(16,423)	(7,679)	(97)
Accounts payable and accrued expenses	1,436	29,977	(1,518)	15,809
Other liabilities	0	(186)	0	0
Deferred revenue	0	65,000	0	0
Net cash used in operating activities	(130,664)	(222,442)	(133,426)	(62,250)
Cash flows from investing activities:
Purchases of marketable securities	0	0	(10,380)	(131,610)
Proceeds from sales/maturities of marketable securities	21,818	0	95,112	57,183
Purchases of property and equipment	(11,213)	(6,849)	(9,975)	(1,837)
Net cash (used in) provided by investing activities	10,605	(6,849)	74,757	(76,264)
Cash flows from financing activities:
Exercise of stock options, net	176	2,553	2,261	4,290
Exercise of warrants	1,688	0	78,226	0
Sale of preferred stock, net of related expenses	0	0	0	121,782
Proceeds from public offering of common stock	0	273,031	299,467	28,578
Proceeds from the issuance of non-recourse debt	0	0	182,216	0
Debt conversion fees	0	0	(530)	0
Tax withholding payments for stock-based compensation	(192)	0	(1,521)	(546)
Net cash provided by financing activities	1,672	347,181	627,903	168,804
Effect of changes in exchange rates on cash, cash equivalents and restricted cash	(22)	(22)	(46)	(100)
Net increase (decrease) in cash, cash equivalents and restricted cash	(118,409)	117,868	569,188	30,190
Cash, cash equivalents, and restricted cash beginning of period	612,582	494,173	43,394	13,204
Cash, cash equivalents, and restricted cash end of period	494,173	612,041	612,582	43,394
Supplemental disclosure of cash flow information:
Interest paid	475	338	2,850	4,750
Income taxes paid	0	0	0	24
Schedule of non-cash investing and financing activities:
Issuance of common shares for debt conversion	13,757	0	92,307	0
Accrued capital expenditures	795	101	2,173	0
Non-cash component of warrant exercise	7,569	0	0	0
Shares received in cashless exercise	2,450	1,271	0	0
Total cash, cash equivalents and restricted cash	612,582	494,173	612,582	13,204
Market Offering
Cash flows from financing activities:
Proceeds from private offering of common stock	0	71,597	0	0
Private placement
Cash flows from financing activities:
Proceeds from private offering of common stock	$ 0	$ 0	$ 67,784	$ 14,700

Business Overview and Summary o

Business Overview and Summary of Significant Accounting Polices	12 Months Ended
	Dec. 31, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Business Overview and Summary of Significant Accounting Policies	Business Overview and Summary of Significant Accounting Policies Immunomedics, Inc., a Delaware corporation, together with its subsidiaries (collectively "we," "our," "us," "Immunomedics", or the "Company"), is a clinical-stage biopharmaceutical company that develops monoclonal antibody-based products for the targeted treatment of cancer. Immunomedics manages its operations as one line of business of researching, developing, manufacturing and marketing biopharmaceutical products, particularly antibody-based products for patients with difficult to treat solid tumor and blood cancers. The Company currently reports as a single industry segment with substantially all business conducted in the United States. Immunomedics conducts its research activities in the United States and runs its development studies in the United States and selected European countries. Our corporate objective is to become a fully-integrated biopharmaceutical company and a leader in the field of antibody-drug conjugates (“ADCs”). To that end, our immediate priority is to commercialize our most advanced ADC product candidate, sacituzumab govitecan ("IMMU-132"), beginning in the United States, with metastatic triple-negative breast cancer (“mTNBC”) as the first indication. In May 2018, we submitted a Biologics License Application (“BLA”) to the United States Food and Drug Administration ("FDA") for sacituzumab govitecan for the treatment of patients with mTNBC who have received at least two prior therapies for metastatic disease. In July 2018, we received notification from the FDA that the BLA was accepted for filing and the original application was granted Priority Review with a Prescription Drug User Fee Act ("PDUFA") target action date in January 2019. In January 2019, we received a Complete Response Letter ("CRL") from the FDA for the BLA. We subsequently met with the FDA in May 2019 to review the FDA’s findings and discussed our BLA resubmission. Since then, we have developed a detailed plan to address the chemistry, manufacturing, and controls (“CMC”) matters raised in the CRL and in our pre-approval inspection. We held another meeting with the FDA in September 2019 to update the FDA on our progress in addressing these matters and to receive feedback from the FDA on our approach. On November 30, 2019, we resubmitted our BLA to the FDA and on December 23, 2019 we received notification from the FDA that the BLA was accepted for filing and further assigned a new PDUFA target action date as June 2, 2020. We have dedicated, and continue to commit, significant resources to address the CMC matters identified by the FDA, while, in parallel, preparing our manufacturing facility to be ready for re-inspection by the FDA. Our Phase 3 confirmatory ASCENT study for sacituzumab govitecan has reached its target enrollment for mTNBC patients previously treated with at least two systemic chemotherapy regimens. Top-line data for the ASCENT study is expected to be available around mid-2020. The Company has a foreign subsidiary, Immunomedics GmbH in Rodermark, Germany, that assists the Company in managing sales and marketing efforts and coordinating clinical trials in Europe. The accompanying consolidated financial statements include results for its foreign subsidiary and its majority-owned United States subsidiary, IBC Pharmaceuticals, Inc. ("IBC"). Immunomedics is subject to significant risks and uncertainties, including, without limitation, the Company's inability to further identify, develop and achieve commercial success for new products and technologies; the possibility of delays in the research and development necessary to select drug development candidates and delays in clinical trials; the risk that clinical trials may not result in marketable products; the risk that the Company may be unable to secure regulatory approval of and market its drug candidates; the development or regulatory approval of competing products; the Company's ability to protect its proprietary technologies; patent infringement claims; and risks of new, changing and competitive technologies, and regulations in the United States and internationally. Since its inception in 1982, Immunomedics’ principal sources of funds have been the private and public sale of equity and debt securities, and revenues from licensing agreements, including up-front and milestone payments, funding of development programs, and other forms of funding from collaborations. The Company expects to continue to fund its operations with its current financial resources. Summary of Significant Accounting Policies: Basis of Presentation The consolidated financial statements include the accounts of Immunomedics and its subsidiaries. Noncontrolling interests in consolidated subsidiaries in the consolidated balance sheets represent minority stockholders' proportionate share of the equity (deficit) in such subsidiaries. All intercompany balances and transactions have been eliminated in consolidation. In this Annual Report, the periods presented are the year ended December 31, 2019, the six-month transition period from July 1, 2018 to December 31, 2018 (which we sometimes refer to as the "Transition Period") and our fiscal years ended June 30, 2018 and 2017 (which are referred to as “fiscal 2018,” and "fiscal 2017", as if we had not changed our fiscal year to a calendar year). Use of Estimates The preparation of consolidated financial statements in conformity with United States generally accepted accounting principles 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 consolidated financial statements and the reported amounts of revenues and expenses during the reported period. Actual results could differ from those estimates. The Company’s significant estimates and assumptions relate to stock-based compensation expenses, the fair value for the liability related to sale of future royalties and related interest expense. Interest Expense on Liability Related to Sale of Future Royalties The Company accounts for the liability related to the sale of future royalties as a debt financing. The Company has a significant continuing involvement in the generation of related royalty streams. The Company accretes this liability and recognizes expected interest expense using the effective interest rate method over the life of the related royalty stream, based on our current estimates of future royalty payments. These estimates include projections the Company makes and projections from outside the Company and involves significant judgment and inherent uncertainties. The Company periodically re-assesses the projections and, to the extent our future projections are greater or less than its previous estimates or the estimated timing of such payments is materially different than its previous estimates, the Company will adjust the effective interest calculation. Foreign Currencies For our German subsidiary which operates in a local currency environment, income and expense items are translated to United States dollars at the monthly average rates of exchange prevailing during the year, assets and liabilities are translated at year-end exchange rates and equity accounts are translated at historical exchange rates. Translation adjustments are accumulated in a separate component of stockholders' equity in the consolidated balance sheets and the consolidated statements of changes in stockholders’ equity and are included in the determination of comprehensive (loss) income in the consolidated statements of comprehensive loss. Transaction gains and losses are included in the determination of net loss in the consolidated statements of comprehensive loss. Financial Instruments The carrying amount of cash and cash equivalents, prepaid expenses, other current assets and current liabilities approximate fair value due to the short-term maturity of these instruments. The Company considers all highly liquid investments with an original maturity of three months or less when purchased to be cash equivalents. Marketable Securities Marketable securities, all of which are available-for-sale, consist of United States Government sponsored agencies which are carried at fair value, with unrealized gains and losses, net of related income taxes, reported as accumulated other comprehensive loss, except for losses from impairments which are determined to be other-than-temporary. Realized gains and losses and declines in value judged to be other-than-temporary on available-for-sale securities are included in the determination of net loss and are included in interest and other income (net), at which time the average cost basis of these securities are adjusted to fair value. Fair values are based on quoted market prices at the reporting date. Interest and dividends on available-for-sale securities are included in interest and other income (net). Property and Equipment Property and equipment are stated at cost less accumulated depreciation and amortization. Depreciation expense is computed using the straight-line method over the estimated useful lives of the assets, including leasehold improvements and capital lease assets that are amortized over the shorter of their useful lives or the terms of the respective leases. The Company generally uses the following range of useful lives for its property and equipment categories: leasehold improvements— 7 to 10 years ; computer equipment— 5 years ; machinery and equipment— 5 to 10 years ; and furniture and fixtures— 10 years . Depreciation expense includes amortization of assets related to capital leases. The Company charges repairs and maintenance costs to expense as incurred. Concentration of Credit Risk Cash, cash equivalents, and marketable securities are financial instruments that potentially subject the Company to concentration of credit risk. Our investment policy is to invest only in institutions that meet high credit quality standards and establishes limits on the amount and time to maturity of investments with any individual counterparty. The policy also requires that investments are only entered into with corporate and financial institutions that meet high credit quality standards. Restricted cash represents funds the Company is required to set aside to cover vehicle operating leases and other purposes. Revenue Recognition Pursuant to Topic 606, we recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. To achieve this core principle, Topic 606 includes provisions within a five step model that includes i) identifying the contract with a customer, ii) identifying the performance obligations in the contract, iii) determining the transaction price, iv) allocating the transaction price to the performance obligations, and v) recognizing revenue when, or as, an entity satisfies a performance obligation. At contract inception, we assess the goods or services promised within each contract and assess whether each promised good or service is distinct and determine those that are performance obligations. We then recognize as revenue the amount of the transaction price that is allocated to the respective performance obligation when the performance obligation is satisfied. Research and Development Costs Research and development costs are expensed as incurred. Costs incurred for clinical trials for patients and investigators are expensed as services are performed in accordance with the agreements in place with the institutions. Research and development costs include salaries and benefits, costs associated with producing biopharmaceutical compounds, laboratory supplies, the costs of conducting clinical trials, and facilities costs. In addition, the Company uses clinical research organizations and contract manufacturing operations to outsource portions of our research and development activities. Treasury Shares The Company records treasury stock at the cost to acquire it and includes treasury stock as a component of Stockholders’ Equity. In determining the cost of the treasury shares when either sold or issued, the Company uses the first-in, first-out method ("FIFO"). If the proceeds from the sale of the treasury shares are greater than the cost of the shares sold, the excess proceeds are recorded as additional paid-in capital. If the proceeds from the sale of the treasury shares are less than the original cost of the shares sold, the excess cost reduces any additional paid-in capital arising from previous sales of treasury shares for that class of stock. Fair Value Measurements The Company categorizes its financial instruments measured at fair value into a three-level fair value hierarchy that prioritizes the inputs used in determining the fair value of the asset or liability. The three levels of the fair value hierarchy are as follows: • Level 1 - Financial instruments whose values are based on unadjusted quoted prices for identical assets or liabilities in an active market which the company has the ability to access at the measurement date (examples include active exchange-traded securities and most United States Government and agency securities). • Level 2 - Financial instruments whose value are based on quoted market prices in markets where trading occurs infrequently or whose values are based on quoted prices of instruments with similar attributes in active markets. • Level 3 - Financial instruments whose values are based on prices or valuation techniques that require inputs that are both unobservable and significant to the overall fair value measurement. These inputs reflect management's own assumptions about the assumptions a market participant would use in pricing the asset. The Company’s financial instruments consist of cash and cash equivalents, marketable securities, prepaid expenses, other current assets, accounts payable and accrued expenses, convertible senior notes, liabilities related to the sale of future royalties and Convertible Senior Notes. The carrying amount of prepaid expenses, other current assets, accounts payable and accrued expenses and certain other liabilities are generally considered to be representative of their respective fair values because of the short-term nature of those instruments. Income Taxes The Company uses the asset and liability method to account for income taxes, including the recognition of deferred tax assets and deferred tax liabilities for the anticipated future tax consequences attributable to differences between financial statements amounts and their respective tax bases. The Company reviews its deferred tax assets for recovery. A valuation allowance is established when the Company believes that it is more likely than not that its deferred tax assets will not be realized. Changes in valuation allowances from period to period are included in the Company’s tax provision in the period of change. The Company has recorded a full valuation allowance against its net deferred tax assets as of December 31, 2019 and 2018 . The Tax Cuts and Jobs Act (the "Act") was signed into law on December 22, 2017. Among its numerous changes to the Internal Revenue Code, the Act reduces United States corporate rates from 35% to 21%. Additionally, the Act limits the use of net operating loss carry backs, however any future net operating losses will instead be carried forward indefinitely. Only 80% of current income will be able to be offset with a net operating loss carryforward, with the remainder of the net operating loss continuing to carry forward. As a result of the reduction in the U.S. corporate income tax rate, the Company revalued its ending net deferred tax assets as of June 30, 2018, which resulted in a provisional expense of $59.5 million which was offset by an associated change in valuation allowance. In the second quarter of the Transition Period, the Company completed its analysis to determine the effect of the Tax Act and recorded no further adjustments. Net Loss Per Share Allocable to Common Stockholders Net loss per basic and diluted common share allocable to common stockholders is based on the net loss for the relevant period, divided by the weighted-average number of common shares outstanding during the period. For purposes of the diluted net loss per common share calculations, the exercise or exchange of all potential common shares is not included because their effect would have been anti-dilutive, due to the net loss recorded for the year ended December 31, 2019 , the Transition Period and fiscal years ended June 2018, and 2017, respectively. The common stock equivalents excluded from the earnings per share calculation are 8.2 million , 6.7 million , 10.0 million , and 66.1 million for the year ended December 31, 2019 , the Transition Period and the fiscal years ended June 2018, and 2017, respectively. Net Comprehensive Loss Net comprehensive loss consists of net loss, unrealized gain (loss) on available for sale securities and foreign exchange translation adjustments and is presented in the consolidated statements of comprehensive loss. Stock-Based Compensation The Company utilizes stock-based compensation in the form of stock options, stock appreciation rights, stock awards, stock unit awards, performance shares, cash-based performance units and other stock-based awards, each of which may be granted separately or in tandem with other awards. The grant-date fair value of stock awards is based upon the underlying price of the stock on the date of grant. The grant-date fair value of stock option awards must be determined using an option pricing model. Option pricing models require the use of estimates and assumptions as to (a) the expected term of the option, (b) the expected volatility of the price of the underlying stock and (c) the risk-free interest rate for the expected term of the option. The Company uses the Black-Scholes option pricing formula for determining the grant-date fair value of such awards. The fair value of option awards that vest based on achievement of certain market conditions are determined using a Monte Carlo simulation technique. The expected term of the option is based upon the contractual term and expected employee exercise and expected post-vesting employment termination behavior. The expected volatility of the price of the underlying stock is based upon the historical volatility of the Company’s stock computed over a period of time equal to the expected term of the option. The risk-free interest rate is based upon the implied yields currently available from the United States Treasury yield curve in effect at the time of the grant. Forfeitures are recorded as incurred. Recently Issued Accounting Pronouncements Accounting Pronouncements adopted during the year The Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2019-01, “Leases Topic 842,” requiring entities to recognize assets and liabilities on the balance sheet for all leases, with certain exceptions. Topic 842 allows for a modified retrospective application and is effective as of the first quarter of 2019. Entities are allowed to apply the new guidance using a modified retrospective approach at the beginning of the year in which new lease standard is adopted, rather than to the earliest comparative period presented in their financial statements. The modified retrospective approach includes a number of optional practical expedients that entities may elect to apply. We elected the modified retrospective approach under the new guidance and elected the available practical expedients on adoption. Upon adoption, we recognized additional operating lease liabilities of $8.4 million with a corresponding right-of-use assets of $8.4 million based on the present value of the remaining lease payments under existing operating leases. As of December 31, 2018, we had $2.1 million in deferred charges related to our real estate leases that were recorded against the lease liability asset as part of the transition, resulting in $10.5 million included in other long-term liabilities on our consolidated balance sheets. In addition, the new guidance resulted in additional lease-related disclosures in the footnotes to our consolidated financial statements. Our leasing portfolio is comprised entirely of operating leases, and we do not recognize right-of-use assets or related lease liabilities with a lease term of twelve months or less on our consolidated balance sheets. Adoption of Topic 842 has required changes to our business processes and controls to comply with the provisions of the standard. Refer to Note 14 "Commitments and Contingencies" for additional information. In June 2018, the FASB issued ASU 2018-07, "Compensation-Stock Compensation," to improve the usefulness of information provided to users of financial statements while reducing cost and complexity in financial reporting and provide guidance aligning the measurement and classification for share-based payments to nonemployees with the guidance for share-based payments to employees. Under the guidance, the measurement of equity-classified nonemployee awards will be fixed at the grant date. This standard is effective for fiscal years beginning after December 15, 2018, and interim periods within those annual periods. Early adoption is permitted, but no earlier than an entity's adoption date of ASU 2014-09, “Revenue from Contracts with Customers (Topic 606).” We adopted ASU 2018-07 during the first quarter of 2019 and the adoption did not have a material impact to our consolidated financial statements. Accounting Pronouncements yet to be adopted In November 2018, the FASB issued ASU 2018-18, "Collaborative Arrangements (Topic 808): Clarifying the Interaction between Topic 808 and Topic 606," to clarify when ASC 606 should be used for collaborative arrangements when the counterparty is a customer. The guidance precludes an entity from presenting consideration from a transaction in a collaborative arrangement as revenue from contracts with customers if the counterparty is not a customer for that transaction. The guidance is effective for public business entities in fiscal years beginning after December 15, 2019, and interim periods therein. Early adoption is permitted to entities that have adopted ASC 606. We are currently assessing the impact of ASU 2018-18. In August 2018, the FASB issued ASU 2018-13, "Fair Value measurement (Topic 820): Disclosure Framework - Changes to the Disclosure Requirements for Fair Value Measurement," to no longer require public companies to disclose transfers between Level 1 and Level 2 of the fair value hierarchy, and to require disclosure about the range and weighted average used to develop significant unobservable inputs for Level 3 fair value measurements. The guidance is effective for fiscal years beginning after December 15, 2019, and for interim periods within those fiscal years. Entities are permitted to early adopt either the entire standard or only the provisions that eliminate or modify the requirements. We are currently assessing the impact of ASU 2018-13.

Revenue Recognition

Revenue Recognition	12 Months Ended
	Dec. 31, 2019
Revenue from Contract with Customer [Abstract]
Revenue Recognition	Revenue Recognition Everest Medicines II Limited On April 29, 2019, we entered into a license agreement (the "License Agreement") with Everest Medicines II Limited, a China limited company ("Everest"). Pursuant to the License Agreement, we granted Everest an exclusive license to develop and commercialize sacituzumab govitecan in the People's Republic of China, Taiwan, Hong Kong, Macao, Indonesia, Philippines, Vietnam, Thailand, South Korea, Malaysia, Singapore and Mongolia (the "Territory"). In consideration for entering into the License Agreement, Everest made a one-time, non-refundable upfront payment to us in the aggregate amount of $65.0 million which is recorded as deferred revenue on the consolidated balance sheet as of December 31, 2019 . The License Agreement contains a development milestone payment of $60.0 million based upon our achievement of FDA approval for sacituzumab govitecan. The License Agreement also contains additional development milestone payments in a total amount of up to $180.0 million based upon the achievement of certain other development milestones. In addition, the License Agreement contains sales milestone payments in a total amount of up to $530.0 million based upon the achievement of certain sales milestones. Everest will make royalty payments to us based upon percentages of net sales of sacituzumab govitecan, ranging from 14% to 20% . The Company assessed the arrangement in accordance with ASC 606 and concluded that the contract counterparty, Everest, is a customer based on the arrangement structure. The Company identified two material promises to deliver under the contract: (1) grant of license and the (2) clinical and commercial supply of the product. However, given the nature of the manufacturing of the product the license is not considered to be distinct from the clinical and commercial supply promise. The Company therefore concluded that there is one combined performance obligation. The Company initially deferred and will recognize the $65.0 million over the performance obligation period of the combined performance obligation. As it relates to the upfront consideration, the $65.0 million is recorded as deferred revenue and will be recognized over the term of the of the contract performance obligation period, which the Company has concluded to be 15 years after initial sale of the product in the territory. As concluded above, the Company has a combined performance obligation, which includes delivering the license and clinical and commercial supply to Everest. As such, because the clinical and commercial supply obligation occur throughout the period of the License Agreement, the $65.0 million fixed consideration is recognized over the period in which commercial and clinical supply of product is delivered (over-time). The future potential milestone payments are excluded from the transaction price, as the achievement of the milestone events require considerable judgment in determining whether it is probable of being achieved, and that a significant revenue reversal would not occur. As such, all milestone payments are fully constrained. The Company will reevaluate the transaction price at the end of each reporting period and as uncertain events are resolved or other changes in circumstances occur, and, if necessary, adjust its estimate of the transaction price. Janssen Biotech Inc. On April 5, 2019, the Company entered into a promotion agreement (the "Promotion Agreement") with Janssen Biotech Inc., ("Janssen") pursuant to which the Company will provide non-exclusive product detailing services to Janssen for erdafitinib (the "Product"). Pursuant to the Promotion Agreement, the Company will provide a dedicated sales team to detail the Product to oncologists and other targeted health care providers in the United States. Under the terms of the Promotion Agreement, Janssen maintains ownership of the New Drug Application for the Product as well as legal, regulatory, distribution, commercialization and manufacturing responsibilities for the Product, while the Company will provide product detailing services to Janssen. Following the achievement of certain sales targets in 2019 and 2020, Janssen will pay the Company (a) a service fee equal to a percentage in the low double digits of the portion of Cumulative Net Sales (as defined in the Promotion Agreement) in excess of a baseline amount during each of 2019 and 2020, and (b) potential milestone payments of up to $15.0 million when Cumulative Net Sales exceed certain thresholds during each of 2019 and 2020. On April 12, 2019, the Company was informed that the FDA granted accelerated approval to Janssen's Balversa ® (erdafitinib) for the treatment of adult patients with locally advanced or metastatic urothelial carcinoma that has a type of susceptible genetic alteration known as FGFR3 or FGFR2, and that has progressed during or following prior platinum-containing chemotherapy. During the year ended December 31, 2019 , $0.3 million

Marketable Securities

Marketable Securities	12 Months Ended
	Dec. 31, 2019
Investments, Debt and Equity Securities [Abstract]
Marketable Securities	Marketable Securities Immunomedics considers all of its current investments to be available-for-sale. Marketable securities are carried at fair value, with unrealized gains and losses, net of related income taxes, reported as accumulated other comprehensive (loss) income, except for losses from impairments which are determined to be other-than-temporary. Realized gains and losses and declines in value judged to be other-than-temporary on available-for-sale securities are included in the determination of net loss and are included in interest and other income (net), at which time the average cost basis of these securities are adjusted to fair value. Fair values are based on quoted market prices at the reporting date. Interest and dividends on available-for-sale securities are included in interest and other income (net). As of December 31, 2019, and 2018, the carrying value of our current investments due after one year or more are $4.5 million and $4.9 million , respectively. The following table summarizes the marketable securities held as of December 31, 2019 and 2018 (in thousands): December 31, 2019 Amortized Cost Gross Unrealized Gain Gross Unrealized (Loss) Fair Value U.S. Government Sponsored Agencies $ 4,941 $ — $ (391 ) $ 4,550 December 31, 2018 Amortized Cost Gross Unrealized Gain Gross Unrealized (Loss) Fair Value U.S. Government Sponsored Agencies $ 4,941 $ — $ — $ 4,941

Debt

Debt	12 Months Ended
	Dec. 31, 2019
Debt Disclosure [Abstract]
Debt	Debt Liability related to sale of future royalties On January 7, 2018 , the Company entered into a funding agreement (the "Funding Agreement") with RPI Finance Trust, a Delaware statutory trust ("RPI"). Pursuant to the Funding Agreement, the Company issued to RPI the right to receive certain royalty amounts, subject to certain reductions, based on the net sales of the ADC sacituzumab govitecan, for each calendar quarter during the term of the Funding Agreement ("Revenue Participation Right"), in exchange for $175.0 million in cash (the "Purchase Price"). Specifically, the royalty rate commences at 4.15 percent on net annual sales of up to $2.0 billion , declining step-wise based on sales tiers to 1.75 percent on net global annual sales exceeding $6.0 billion . On January 7, 2018 , in connection with the Funding Agreement, the Company entered into a common stock purchase agreement (the "Purchase Agreement") with RPI, pursuant to which the Company, in a private placement, issued and sold to RPI approximately 4.4 million unregistered shares (the "Shares") of the Company's Common Stock, at a price of $17.15 per share for gross proceeds to the Company of $75.0 million before deducting fees and expenses (the "Financing"). The Company concluded that there were two units of accounting in the transaction. The Company allocated the transaction consideration on a relative fair value to the liability and common stock in accordance with ASC 470-10 as follows (in thousands): Units of Accounting: Allocated Consideration Liability related to sale of future royalties $ 182,216 Common stock 67,784 $ 250,000 Interest will be recognized using the effective interest method over a period of 20 years . The effective interest rate under the Funding Agreement, including issuance costs, is approximately 16.0% as of December 31, 2019 . During the year ended December 31, 2019 , the Transition Period, and the fiscal year ended June 30, 2018 , the Company recognized $39.9 million , $19.3 million , and $19.8 million in interest expense, respectively. The following table shows the activity within the liability related to sale of future royalties during the year ended December 31, 2019 , the Transition Period and at the fiscal year ended June 30, 2018 (in thousands): Liability related to sale of future royalties at January 7, 2018 $ 182,216 Interest expense recognized 19,791 Carrying value of liability related to sale of future royalties at June 30, 2018 $ 202,007 Interest expense recognized 19,288 Carrying value of liability related to sale of future royalties at December 31, 2018 $ 221,295 Interest expense recognized 39,929 Carrying value of liability related to sale of future royalties at December 31, 2019 (includes current portion of $3,455) $ 261,224 Convertible Senior Notes In February 2015, the Company issued $100.0 million of Convertible Senior Notes (the "Convertible Senior Notes") (net proceeds of approximately $96.3 million after deducting the initial purchasers’ fees and offering expenses) in a private offering exempt from registration under the Securities Act of 1933, as amended (the “Securities Act”), in reliance upon Rule 144A under the Securities Act. The Convertible Senior Notes had a maturity date of February 15, 2020 , unless earlier purchased or converted. The debt issuance costs of approximately $3.7 million , primarily consisting of underwriting, legal and other professional fees, and are amortized over the term of the Convertible Senior Notes. The Convertible Senior Notes are senior unsecured obligations of the Company. Interest at 4.75% is payable semiannually on February 15 and August 15 of each year. The effective interest rate on the Convertible Senior Notes was 5.48% for the period from the date of issuance through the year ended December 31, 2019 . The Convertible Senior Notes are convertible at the option of holders into approximately 19.6 million shares of common stock at any time prior to the close of business on the day immediately preceding the maturity date. The exchange rate will initially be 195.8336 shares of common stock per $1,000 principal amount of Convertible Senior Notes (equivalent to an initial conversion price of approximately $5.11 per share of common stock). If the Company undergoes a fundamental change (as defined in the indenture governing the Convertible Senior Notes), holders may require Immunomedics to purchase for cash all or part of the Convertible Senior Notes at a purchase price equal to 100% of the principal amount of the Convertible Senior Notes to be purchased, plus accrued and unpaid interest, if any, to, but excluding, the fundamental change purchase date, subject to certain exceptions. In addition, if certain make-whole fundamental changes (as defined in the indenture governing the Convertible Senior Notes) occur, Immunomedics will, in certain circumstances, increase the conversion rate for any Convertible Note converted in connection with such make-whole fundamental change. The indenture does not limit the amount of debt which may be issued by the Company under the indenture or otherwise, does not contain any financial covenants or restrict the Company from paying dividends, selling or disposing of assets, or issuing or repurchasing its other securities, provided that such event is not deemed to be a fundamental change (as defined in the indenture governing the Convertible Senior Notes). The indenture contains customary terms and covenants and events of default. If an event of default with respect to the Convertible Senior Notes occurs, holders may, upon satisfaction of certain conditions, accelerate the principal amount of the Convertible Senior Notes plus premium, if any, and accrued and unpaid interest, if any. In addition, the principal amount of the Convertible Senior Notes plus premium, if any, and accrued and unpaid interest, if any, will automatically become due and payable in the case of certain types of bankruptcy or insolvency events of default involving the Company. On September 21, 2017 , the Company entered into separate, privately negotiated exchange agreements, (the "September Exchange Agreements") with certain holders of the Convertible Senior Notes. Under the Exchange Agreements, such holders agreed to convert an aggregate $80.0 million of Convertible Senior Notes held by them. In total, the Company issued an aggregate 16.8 million shares of common stock in the September Exchange Agreements. The shares represent an aggregate of 1.1 million shares more than the number of shares into which the exchanged Convertible Senior Notes were convertible under their original terms. As a result of the September Exchange Agreements, the Company recognized a loss on induced exchanges of debt of $13.0 million representing the fair value of the incremental consideration paid to induce the holders to exchange their Convertible Senior Notes for equity (i.e., 1.1 million shares of common stock), based on the closing market price of the Company's Common Stock on the date of the September 2017 Exchange Agreements. On October 2, 2018, the Company entered into privately negotiated exchange agreements (the "October 2018 Exchange Agreements"), with a limited number of holders of the Convertible Senior Notes. Under the Exchange Agreements, such holders agreed to convert an aggregate $12.9 million of Convertible Senior Notes held by them. In total, the Company issued an aggregate 2.6 million shares of common stock in the October 2018 Exchange Agreements. The shares represent an aggregate of 0.1 million shares more than the number of shares into which the exchanged Convertible Senior Notes were convertible under their original terms. As a result of the October 2018 Exchange Agreements, the Company recognized a loss on induced exchanges of debt of $0.9 million representing the fair value of the incremental consideration paid to induce the holders to exchange their Convertible Senior Notes for equity (i.e., 0.1 million shares of common stock), based on the closing market price of the Company's Common Stock on the date of the October 2018 Exchange Agreements. As a result of the October 2018 Exchange Agreements, the balance of the outstanding Convertible Senior Notes was $7.1 million at December 31, 2019 and 2018 . As of February 14, 2020, the remaining $7.1 million of Convertible Senior Notes converted into 1.4 million shares of common stock based on the initial conversion price of approximately $5.11 per share of common stock. Total interest expense for the Convertible Senior Notes were $0.4 million , $0.5 million , $3.5 million , and $5.5 million , for the year ended December 31, 2019 , the Transition Period and the fiscal years ended 2018 and 2017, respectively. Included in interest expense is the amortization of debt issuance costs of $0.1 million for the year ended December 31, 2019 , $0.2 million in the Transition Period ( $0.1 million of which related to the accelerated amortization of debt issuance costs associated with the October 2018 Exchange Agreements), $1.7 million in fiscal 2018 ( $1.4 million of which related to the accelerated amortization of debt issuance costs associated with the September Exchange Agreements), and $0.7 million in fiscal 2017.

Stock-Based Compensation

Stock-Based Compensation	12 Months Ended
	Dec. 31, 2019
Share-based Payment Arrangement [Abstract]
Stock-Based Compensation	Stock-Based Compensation Stock Incentive Plan The Company has a stock incentive plan, the Immunomedics, Inc. 2014 Long-Term Incentive Plan (the “Plan”). The Plan was established to promote the long-term financial interests and growth of the Company, by attracting and retaining management and other personnel and key service providers with the training, experience and ability to enable them to make a substantial contribution to the success of the Company's business. The Plan is designed to motivate management personnel by means of growth-related incentives to achieve long-range goals and further the alignment of interests with those of the stockholders of the Company through opportunities for increased stock or stock-based ownership in the Company. Toward these objectives, the Company may grant stock options, stock appreciation rights, stock awards, stock units, performance shares, performance options, performance units, and other stock-based awards to eligible individuals on the terms and subject to the conditions set forth in the Plan. There have been no significant modifications to the Plan during the year ended December 31, 2019, the Transition Period or fiscal years ended June 30, 2018, or 2017. Stock-based compensation expense was $11.7 million , $0.9 million , $4.0 million , and $4.3 million for the year ended December 31, 2019 , the Transition Period, and fiscal years ended June 30, 2018 and 2017 , respectively. On January 15, 2019, the Company received a final award finding from an arbitrator that denied Dr. Goldenberg 1.5 million of RSU's. As a result, during the Transition Period, $3.4 million of the stock-based compensation expense was reversed. Refer to "Note 14 - Commitments and Contingencies" for more information. Stock Options Stock option grants provide the right to purchase a specified number of shares of Common Stock from the Company at a specified price during a specified period of time. The stock option exercise price per share is the fair market value of one share of Common Stock on the date of the grant of the stock option and generally have a vesting period of four years . As of December 31, 2019 , there was $40.6 million of total unrecognized compensation cost related to non-vested stock-based compensation arrangements granted under the plan. That cost is being recognized over a weighted-average period of 3 years . The weighted average grant date fair value of the stock options granted during the year ended December 31, 2019 , the Transition Period, and fiscal years ended June 30, 2018 , and 2017 was $8.81 per share, $12.90 per share, $8.76 per share, and $2.21 per share, respectively. The weighted average grant date fair value of the performance-based stock options granted during the year ended December 31, 2019, the Transition Period, and fiscal years ended June 30, 2018 , and 2017 was $9.50 , $0.00 , $7.29 and $0.00 per share, respectively. There were no performance-based stock options granted during the Transition Period, or for the fiscal year ended June 30, 2017 . We estimated the fair value of options granted using a Black-Scholes option pricing model with the following assumptions: Year Ended December 31, 2019 Transition Period December 31, 2018 Fiscal Years Ended June 30, 2018 2017 Expected dividend yield —% —% —% —% Expected option term (years) 4.52 4.76 4.84 5.04 Expected stock price volatility 71% 69% 70% 63% Risk-free interest rate 1.39% - 2.58% 2.69% - 3.06% 1.72% - 2.89% 1.16% - 2.15% The following table summarizes all stock option activity for the ended December 31, 2019 : Options (in thousands) Weighted Average Exercise Price Per Option Weighted Average Remaining Contractual Term (Years) Aggregate Intrinsic Value (in thousands) Options outstanding, January 1, 2019 4,757 $ 14.30 5.42 $ 18,618 Changes during the year: Granted 3,614 15.46 Exercised (1,207 ) 3.17 Expired or forfeited (1,263 ) 17.78 Options outstanding, end of year 5,901 $ 16.54 5.90 $ 30,145 Vested as of December 31, 2019 1,150 $ 14.72 4.61 $ 8,276 The following table summarizes all stock option activity for the Transition Period ended December 31, 2018 : Options (in thousands) Weighted Average Exercise Price Per Option Weighted Average Remaining Contractual Term (Years) Aggregate Intrinsic Value (in thousands) Options outstanding, July 1, 2018 3,549 $ 7.58 4.43 $ 57,123 Changes during the year: Granted 2,002 22.54 Exercised (706 ) 3.71 Expired or forfeited (88 ) 15.57 Options outstanding, end of year 4,757 $ 14.30 5.42 $ 18,618 Vested as of December 31, 2018 1,504 $ 4.23 3.41 $ 15,098 The total fair value of shares vested during the year ended December 31, 2019 , the Transition Period, and fiscal years ended June 30, 2018 , and 2017 was $8.9 million , $1.3 million , $0.3 million , and $1.4 million , respectively. The total intrinsic value of stock options exercised during the fiscal year ended December 31, 2019 , the Transition Period, and fiscal years ended June 30, 2018 , and 2017 was $14.7 million , $13.3 million , $7.8 million , and $2.6 million , respectively. Restricted Stock Units ("RSU's") The Company may grant awards of RSU's to eligible individuals. An RSU represents a contractual obligation by the Company to deliver a number of shares of Common Stock equal to the fair market value of the specified number of shares subject to the award, or a combination of shares of Common Stock and cash. Vesting requirements may include performance goals, the attainment of performance goals with continued service, or both. Information regarding the Company's RSU's for the year ended December 31, 2019 is as follows: Non-Vested Restricted Stock Units Share Equivalent (in thousands) Weighted Average Grant Date Fair Value Non-vested at January 1, 2019 15 $ 14.29 Changes during the period: Restricted Units Granted 58 12.93 Vested/Exercised (15 ) 14.29 Forfeited — — Non-vested at December 31, 2019 58 $ 12.93 As of the year ended December 31, 2019 , there was $0.3 million of total unrecognized compensation costs related to the awards. The cost is being recognized over a weighted-average period of 0.4 years. Information regarding the Company's RSU's for the Transition Period ended December 31, 2018 is as follows: Non-Vested Restricted Stock Units Share Equivalent (in thousands) Weighted Average Grant Date Fair Value Non-vested at July 1, 2018 1,535 $ 2.83 Changes during the period: Restricted Units Granted 15 14.29 Vested/Exercised (35 ) 8.46 Forfeited (1,500 ) 2.28 Non-vested at December 31, 2018 15 $ 14.29 As of December 31, 2018 , there was $0.3 million of total unrecognized compensation costs related to the awards. The cost was being recognized over a weighted-average period of 1.18 years . During the Transition Period, the Company received a final award finding from an arbitrator that denied Dr. Goldenberg 1.5 million of RSU's that are included as forfeited in the table above. Refer to "Note 14 - Commitments and Contingencies" for more information. Performance Stock Options ("PSO's") The Company may grant awards of PSO's to eligible individuals. PSO's are shares of Common Stock that vest based on performance measured against predetermined objectives that could include performance goals, continued employment, or a combination of both over a specified performance period. PSO's may be settled in shares of Common Stock, cash, or both as determined on the settlement date. On March 14, 2019, performance stock options were granted to certain individuals that vest upon the Company’s receipt of approval from the FDA for the Company’s BLA for sacituzumab govitecan for the treatment of patients with metastatic triple-negative breast cancer who have received at least two prior therapies for metastatic disease under the Prescription Drug User Fee Act. There were additional stock options that were granted to certain eligible individuals that vest on the second anniversary of the date of grant. In addition, on April 17, 2019 performance stock options were granted to certain individuals that vest upon achievement of defined sales performance milestones. The following table summarizes the Company's performance-based stock option activity for the year ended December 31, 2019 is as follows: Options (in thousands) Weighted Average Exercise Price Per Option Weighted Average Remaining Contractual Term (Years) Aggregate Intrinsic Value (in thousands) Options outstanding, January 1, 2019 538 $ 13.09 6.04 $ 772 Changes during the year: Granted 800 17.18 Exercised — — Expired or forfeited (501 ) 13.05 Options outstanding, end of year 837 $ 17.03 6.26 $ 3,456 Vested as of December 31, 2019 50 $ 18.74 6.88 $ 121 The total fair value of shares vested during the year ended December 31, 2019 was $1.1 million . As of the year ended December 31, 2019 , there was $4.9 million of total unrecognized compensation costs related to the awards. The cost is being recognized over a remaining weighted-average period of 0.8 years. The following table summarizes the Company's performance-based stock option activity for the Transition Period ended December 31, 2018 is as follows: Options (in thousands) Weighted Average Exercise Price Per Option Weighted Average Remaining Contractual Term (Years) Aggregate Intrinsic Value (in thousands) Options outstanding, July 1, 2018 538 $ 13.09 6.54 $ 5,688 Changes during the year: Granted — — Exercised — — Expired or forfeited — — Options outstanding, end of year 538 $ 13.09 6.04 $ 772 Vested as of December 31, 2018 38 $ 11.86 5.94 $ 91 As of December 31, 2018 , there was $3.0 million of total unrecognized compensation costs related to the awards. The cost was being recognized over a remaining weighted-average period of 3.05 . There were no performance stock options granted during the Transition Period.

Estimated Fair Value of Financi

Estimated Fair Value of Financial Instruments	12 Months Ended
	Dec. 31, 2019
Fair Value Disclosures [Abstract]
Estimated Fair Value of Financial Instruments	Estimated Fair Value of Financial Instruments Cash Equivalents and Marketable Securities ($ in thousands) As of December 31, 2019 Level 1 Level 2 Level 3 Total Money Market Funds Note (a) $ 550,788 $ — $ — $ 550,788 Marketable Securities: U.S. Government Sponsored Agencies 4,550 — — 4,550 Total $ 555,338 $ — $ — $ 555,338 ($ in thousands) As of December 31, 2018 Level 1 Level 2 Level 3 Total Money Market Funds Note (a) $ 326,239 $ — $ — $ 326,239 Marketable Securities: U.S. Government Sponsored Agencies 4,941 — — 4,941 Total $ 331,180 $ — $ — $ 331,180 (a) The money market funds noted above are included in cash and cash equivalents. Convertible Senior Notes The carrying amounts and estimated fair values (Level 2) of debt instruments are as follows (in thousands): As of December 31, 2019 As of December 31, 2018 Carrying Amount Estimated Fair Value Carrying Amount Estimated Fair Value Convertible Senior Notes $ 7,106 $ 28,900 $ 7,055 $ 20,100 The fair value of the Convertible Senior Notes, which differs from their carrying values, is influenced by interest rates, the Company’s stock price and stock price volatility and is determined by prices for the Convertible Senior Notes observed in market trading which are Level 2 inputs. Liability Related to the Sale of Future Royalties The Company has determined the fair value of the liability related to the sale of future royalties is based on the Company's current estimates of future royalties expected to be paid to RPI, over the life of the arrangement, which are considered Level 3 (See Note 4 - "Debt"). There were no transfers between Level 1, Level 2, and Level 3 during the periods presented.

Property and Equipment

Property and Equipment	12 Months Ended
	Dec. 31, 2019
Property, Plant and Equipment [Abstract]
Property and Equipment	Property and Equipment Property and equipment consisted of the following as of December 31, (in thousands): 2019 2018 Machinery and equipment $ 14,331 $ 16,048 Leasehold improvements 11,535 6,365 Right-of-use asset 8,368 — Furniture and fixtures 1,190 291 Computer equipment 2,596 1,850 Construction in progress 2,667 3,231 40,687 27,785 Accumulated depreciation and amortization (7,925 ) (4,316 ) $ 32,762 $ 23,469 Depreciation and amortization expense for the year ended December 31, 2019 , the Transition Period, and the fiscal years ended June 30, 2018 and 2017, was $3.8 million , $2.1 million , $ 1.3 million and $0.9 million , respectively.

Accounts Payable and Accrued Ex

Accounts Payable and Accrued Expenses	12 Months Ended
	Dec. 31, 2019
Payables and Accruals [Abstract]
Accounts Payable and Accrued Expenses	Accounts Payable and Accrued Expenses Accounts payable and accrued expenses consisted of the following as of December 31, (in thousands): 2019 2018 (a) Trade accounts payable $ 37,758 $ 20,125 Accrued contract manufacturing expenses 11,663 — Accrued employee related expenses 7,403 315 Clinical trial accruals 2,225 5,114 Executive severance liabilities 561 2,198 Miscellaneous other current liabilities 1,250 3,970 $ 60,860 $ 31,722 (a) Certain 2018 amounts have been reclassified to conform with current year presentation.

Stockholders_ Equity

Stockholders’ Equity	12 Months Ended
	Dec. 31, 2019
Stockholders' Equity Note [Abstract]
Stockholders’ Equity	Stockholders’ Equity At the June 29, 2017 Special Meeting, the Company’s stockholders approved the amendment and restatement of the Company’s Certificate of Incorporation to increase the maximum number of shares of the Company’s stock authorized up to 260,000,000 shares of stock consisting of 250,000,000 shares of common stock and 10,000,000 shares of preferred stock. Previously the Company’s Certificate of Incorporation authorized up to 165,000,000 shares of capital stock, consisting of 155,000,000 shares of common stock and 10,000,000 shares of preferred stock. Preferred Stock The Certificate of Incorporation of the Company authorizes 10,000,000 shares of preferred stock, $.01 par value per share. The preferred stock may be issued from time to time in one or more series, with such distinctive serial designations, rights and preferences as shall be determined by the Board of Directors. On May 10, 2017, the Company issued in a private placement 1,000,000 shares (the “Preferred Shares”) of the Company’s Series A-1 Convertible Preferred Stock at a price of $125 per share for gross proceeds to the Company of $125.0 million , before deducting fees and expenses (the “Financing”). Each Preferred Share will be convertible into 23.10536 shares of common stock (or an aggregate of 23,105,348 shares of common stock). The conversion price per share of common stock is $5.41 . At December 31, 2019 and 2018, the Company had no preferred stock outstanding. Following the June 29, 2017 Special Meeting and filing the Charter Amendment with the State of Delaware, the Company had authorized a sufficient number of unreserved shares of common stock to permit the exchange of the Preferred Shares. On July 31, 2017, the Company filed a registration statement on Form S-3 to register for resale the 23,105,348 shares of the Company's common stock issuable upon the exchange of the Series A-1 Convertible Preferred Stock. The Preferred Shares converted to shares of common stock on August 24, 2017. The registration statement was declared effective on September 19, 2017. Common Stock On October 11, 2016, the Company completed an underwritten public offering of 10,000,000 shares of its common stock and accompanying warrants to purchase 10,000,000 shares of common stock at a purchase price of $3.00 per unit, comprising of one share of common stock and one warrant. The Company received gross and net proceeds of $30.0 million and approximately $28.6 million , respectively after deducting the underwriting discounts and commissions and estimated expenses related to the offering payable. The warrants became exercisable nine months following the date of issuance and will expire on the second anniversary of the date of issuance and have an exercise price of $3.75 . On the date of issuance, the fair value of these warrants was determined to be $7.3 million and recognized as a liability. The warrants under certain situations require cash settlement by the Company. During fiscal 2018 there were 9,550,000 warrants exercised. The fair value of the 9,550,000 exercised warrants increased $102.1 million from June 30, 2017 to the dates of exercise which has been recognized in the accompanying consolidated statements of comprehensive loss. As of the fiscal year ended June 30, 2018, there were 450,000 warrants outstanding. During the transition period ended December 31, 2018, the remaining 450,000 warrants were exercised for which we received $1.7 million in cash. As of December 31, 2019, and 2018, there were no warrants outstanding. On February 10, 2017, in connection with the execution of a License Agreement, the Company entered into the Securities Purchase Agreement (“SPA”) with Seattle Genetics. Under the SPA, Seattle Genetics purchased 3,000,000 shares (the “Common Shares”) of the Company’s common stock at a price of $4.90 per share, for aggregate proceeds of $14.7 million . Concurrently with the sale of the Common Shares, pursuant to the SPA, the Company also agreed to issue the three -year warrant to purchase an aggregate of 8,655,804 shares of common stock. On July 31, 2017, the Company filed a registration statement on Form S-3 to register the 3,000,000 shares of Company’s common stock and 8,655,804 shares of common stock issuable upon the exercise of the warrants (in addition to the shares issuable upon the conversion of our Series A-1 Convertible Preferred Stock, as discussed above). The warrant became exercisable for cash on February 16, 2017 and expired on January 31, 2018. The warrant was issued on February 16, 2017 and was originally exercisable until February 10, 2020. On the date of issuance, the fair value of these warrants was determined to be $22.3 million . The difference between such fair value and the proceeds of $14.7 million has been recognized as an expense and presented in the consolidated statements of comprehensive loss as a “warrant related expense.” On May 4, 2017, the Company and Seattle Genetics entered into the Termination Agreement, pursuant to which the Company and Seattle Genetics relinquished their respective rights under the License Agreement and agreed to amend the terms of the warrant to amend the expiration date from February 10, 2020 to December 31, 2017. On December 5, 2017, Seattle Genetics exercised the Warrants they held in full to acquire 8,655,804 shares of Common Stock for an aggregate purchase price of $42.4 million . On June 15, 2018, we announced the closing of our public offering of 11,500,000 shares of our common stock at a price of $24.00 per share. Pursuant to the underwriter's full exercise of the over-allotment option granted by us, on June 22, 2018, we closed on the sale of an additional 1,725,000 shares of our common stock for a total of 13,225,000 shares. The total net proceeds from the offering, including the exercise of the over-allotment option, were $299.5 million , after deducting $17.4 million in underwriting discounts and commissions and other offering expenses payable by the Company. On December 9, 2019, we closed an underwritten public offering of 14,285,715 shares of its common stock at a public offering price of $17.50 per share, representing gross proceeds of approximately $ 250.0 million . In addition, the Company granted the underwriters a 30-day option to purchase up to 2,142,857 additional shares of common stock for a total of 16,428,572 shares. We received gross proceeds of $287.5 million and net proceeds of $273.0 million after deducting the underwriting discounts and commissions and expenses related to the offering. At-the-Market Offering On March 29, 2019, the Company entered into a sales agreement (the "ATM Agreement") with Cowen and Company, LLC ("Cowen") to issue and sell shares of the Company’s common stock, par value $0.01 per share, having an aggregate offering price of up to $150.0 million , from time to time during the term of the ATM Agreement, through an “at-the-market” equity offering program at the Company's sole discretion, under which Cowen will act as the Company’s agent and/or principal. The Company will pay Cowen a commission up to 3.0% of the gross sales proceeds of any common stock sold through Cowen under the ATM Agreement. During the year ended December 31, 2019 , the Company sold 4,432,416 shares of common stock with net proceeds of $71.6 million at a weighted average price of $16.40 (excluding commissions) under the ATM Agreement. Treasury Stock During the year ended December 31, 2019 , there were 84,896 shares received in connection with a non-cash equity transaction related to the Company's Plan. During the Transition Period, there were 105,959 treasury shares received in connection with a non-cash equity transaction related to the Company's Plan and the shares were subsequently retired.

Accumulated Other Comprehensive

Accumulated Other Comprehensive (Loss) Income	12 Months Ended
	Dec. 31, 2019
Equity [Abstract]
Accumulated Other Comprehensive (Loss) Income	Accumulated Other Comprehensive (Loss) Income The components of accumulated other comprehensive (loss) income were as follows (in thousands): Currency Translation Adjustments Net Unrealized Gains (Losses) on Available-for-Sale Securities Accumulated Other Comprehensive (Loss) Income Balance at June 30, 2016 $ (172 ) $ 40 $ (132 ) Other comprehensive loss before reclassifications (62 ) (125 ) (187 ) Amounts reclassified from accumulated other comprehensive income (a) — 16 16 Net other comprehensive loss for the year (62 ) (109 ) (171 ) Balance at June 30, 2017 (234 ) (69 ) (303 ) Other comprehensive income (loss) before reclassifications (105 ) 55 (50 ) Amounts reclassified from accumulated other comprehensive income (a) — — — Net other comprehensive (loss) income for the year (105 ) 55 (50 ) Balance at June 30, 2018 (339 ) (14 ) (353 ) Other comprehensive income (loss) before reclassifications (8 ) 10 2 Amounts reclassified from accumulated other comprehensive income (a) — — — Net other comprehensive (loss) income for the year (8 ) 10 2 Balance at December 31, 2018 (347 ) (4 ) (351 ) Other comprehensive loss before reclassifications (21 ) (391 ) (412 ) Amounts reclassified from accumulated other comprehensive income (a) 195 — 195 Net other comprehensive (loss) income for the year 174 (391 ) (217 ) Balance at December 31, 2019 $ (173 ) $ (395 ) $ (568 ) (a) For the year ended December 31, 2019 , the Transition Period ended December 31, 2018, and the fiscal years ended June 30, 2018 and 2017, $0.2 million , $0 , $0 , and $16 thousand , respectively, were reclassified from accumulated other comprehensive (loss) income to interest and other income. All components of accumulated other comprehensive (loss) income are net of tax, except currency translation adjustments, which exclude income taxes related to indefinite investments in foreign subsidiaries.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes Income tax expense for income taxes is as follows (in thousands): Year Ended December 31, 2019 Transition Period Ended December 31, 2018 Fiscal Year Ended June 30, 2018 2017 Federal Current $ — $ — $ — $ — Deferred — — — — Total Federal — — — — State Current — — 2 1 Deferred — — — — Total State — — 2 1 Foreign Current — — 154 19 Deferred — — — — Total Foreign — — 154 19 Total income tax expense $ — $ — $ 156 $ 20 A reconciliation of the statutory tax rates and the effective tax rates for the year ended December 31, 2019 , the transition period ended December 31, 2018 and fiscal years ended June 30, 2018 and 2017 is as follows: Year Ended December 31, 2019 Transition Period Ended December 31, 2018 Fiscal Year Ended June 30, 2018 2017 Statutory rate (21.0 )% (21.0 )% (28.0 )% (34.0 )% Foreign income tax — % — % — % — % Change in valuation allowance 29.9 % 34.4 % 21.1 % 21.9 % State income taxes, (net of federal tax benefit) (7.5 )% (8.8 )% (4.3 )% (4.8 )% Permanent differences, (primarily warrant-related expenses) (1.4 )% (4.2 )% 11.3 % 15.3 % Other — % (0.4 )% — % 1.6 % Effective rate — % — % 0.1 % — % The tax effects of temporary differences that give rise to significant portions of the Company’s deferred tax assets and liabilities as of December 31, (in thousands): 2019 2018 Deferred tax assets: NOL carryforwards $ 203,928 $ 132,841 Research and development credits 28,535 23,118 Liability related to sale of future royalties 49,228 49,217 Deferred revenue 18,286 — Disallowed interest expense 13,474 — Other 5,807 3,088 Total 319,258 208,264 Valuation allowance (317,828 ) (206,397 ) Net deferred assets $ 1,430 $ 1,867 Deferred tax liabilities: Property and equipment $ (1,430 ) $ (1,867 ) Net deferred assets and liabilities $ — $ — A valuation allowance is provided when it is more likely than not that some portion or all of the deferred tax assets will not be realized. The valuation allowances for the year ended December 31, 2019 , and the Transition Period ended December 31, 2018 have been applied to offset the deferred tax assets in recognition of the uncertainty that such tax benefits will be realized as the Company continues to incur losses. The differences between book income and tax income primarily relate to the temporary differences from depreciation and stock compensation expenses, and deferred book income that is realized for tax. At December 31, 2019 , and the Transition Period ended December 31, 2018, the Company has available net operating loss carry forwards for federal income tax reporting purposes of approximately $769.1 million and $516.6 million for state income tax reporting purposes of approximately $593.6 million and $343.0 million , respectively, which expire at various dates between 2020 and 2038. For tax years 2018 onward, Federal net operating losses have an indefinite life but are limited to annual utilization by 80% taxable income. The Company accounts for uncertain tax benefits in accordance with the provisions of section 740-10 of the Accounting for Uncertainty in Income Taxes Topic of the FASB ASC. Of the total unrecognized tax benefits at December 31, 2019 and 2018, approximately $2.5 million was recorded in both years as a reduction to deferred tax assets, which caused a corresponding reduction in the Company’s valuation allowance of $2.5 million in both years. The Company does not anticipate that the amount of unrecognized tax benefits as of December 31, 2019 will change materially within the 12-month period following December 31, 2019 . The change in unrecognized tax benefits are presented below (in thousands): Year Ended December 31, 2019 Transition Period Ended December 31, 2018 Change in unrecognized tax benefits Balance at beginning of year $ 2,521 $ — Gross increases related to current period tax positions — — Gross increases related to prior periods tax positions — 2,521 Gross decreases in tax positions — — Expiration of the statute of limitations — — Balance at end of year $ 2,521 $ 2,521 The Company will recognize potential interest and penalties related to income tax positions as a component of the provision for income taxes on the Consolidated Statements of Comprehensive Loss in any future periods in which the Company must record a liability. The Company is subject to examination for United States Federal and Foreign tax purposes for 2013 and forward and for New Jersey 2015 and forward. The Company conducts business and files tax returns in New Jersey. For fiscal year 2016, the Company sold certain State of New Jersey State Net Operating Losses (“NOL”) and Research and Development (“R&D”) tax credits through the New Jersey Economic Development Authority Technology Business Tax Certificate Transfer Program. Pursuant to such sale, for the year ended June 30, 2016, the Company recorded a tax benefit of $5.1 million , as a result of its sale of approximately $66.2 million , of New Jersey State NOL and $1.5 million of New Jersey R&D tax credits. There were no sales of NOL or R&D for the year ended December 31, 2019 , the Transition Period or 2018 or 2017 fiscal years. The Global Intangible Low-tax Income ("GILTI") provisions of the 2017 Tax Act require the Company to include in its United States income tax return foreign subsidiary earnings in excess of an allowable return on the foreign subsidiary’s tangible assets. The Company expects that it may be subject to incremental United States tax on GILTI income in the future but not for the for the year ended December 31, 2019 . The Company has elected to account for GILTI tax in the period in which it is incurred, and therefore has not provided any deferred tax impacts of GILTI in its consolidated financial statements. As a result of U.S. tax reform legislation, distributions of profits from non-U.S. subsidiaries are not expected to cause a significant incremental U.S. tax impact in the future. However, distributions may be subject to non-U.S. withholding taxes if profits are distributed from certain jurisdictions. U.S. federal income taxes have not been provided on undistributed earnings of our international subsidiaries as it is our intention to reinvest any earnings into the respective subsidiaries. It is not practicable to estimate the amount of tax that might be payable if some or all of such earnings were to be repatriated due to the legal structure and complexity of U.S. and local tax laws. As of December 31, 2019 , and 2018, there are no undistributed earnings. As a result of the reduction in the U.S. corporate income tax rate, the Company revalued its ending net deferred tax assets as of June 30, 2018, which resulted in a provisional expense of $59.5 million

Related Party Transactions

Related Party Transactions	12 Months Ended
	Dec. 31, 2019
Related Party Transactions [Abstract]
Related Party Transactions	Related Party Transactions On January 8, 2018 , Morris Rosenberg joined the Company as Chief Technology Officer and became a full-time employee. Between May 5, 2017 , and January 7, 2018 , Mr. Rosenberg was engaged by the Company as an independent consultant pursuant to a consulting agreement between the Company and Mr. Rosenberg’s consulting company, M Rosenberg BioPharma Consulting LLC. The Company paid M Rosenberg BioPharma Consulting LLC $0.6 million during this time and Morris Rosenberg was also granted stock options to purchase 45,000 shares of the Company's common stock pursuant to the Immunomedics, Inc. 2014 Long-Term Incentive Plan. From January 8, 2018 , through June 30, 2018 , the Company paid M Rosenberg BioPharma $0.8 million , and from July 1, 2018, through the transition period ending December 31, 2018, the Company paid M Rosenberg BioPharma $0.3 million for services agreed upon prior to Mr. Rosenberg becoming a full-time employee. As part of his employment contract, 50% of the 45,000 shares granted to Mr. Rosenberg as a consultant were forfeited, the remaining 50% continue to vest. Mr. Rosenberg received 104,389 stock options and was permitted to continue to provide certain limited outside consulting services through M Rosenberg BioPharma Consulting LLC based on certain restrictions outlined in the contract. Additionally, during his employment period, except with the prior written consent of the Board of Directors, Mr. Rosenberg is not permitted to enter into any contract, agreement or other transaction arrangement to provide goods and/or services to the Company through M Rosenberg BioPharma Consulting LLC. On March 5, 2019, the Company appointed Scott Canute, a member of the Company’s Board, as the Company’s Executive Director. Upon recommendation of the Compensation Committee, the Board approved that Mr. Canute will be paid $16,667 per month for his service as Executive Director and was granted a nonqualified stock option to purchase 79,818 shares of the Company’s common stock (the “Initial Canute Compensation”). The Compensation Committee determined that in order to reflect the scope of his role and the significant time that Mr. Canute will be devoting to his role as Executive Director, Mr. Canute’s cash compensation shall be increased to $21,372 per month, and Mr. Canute was granted an additional nonqualified stock option to purchase 22,854 shares of the Company’s common stock (the “Revised Canute Compensation”). The options have a seven -year term and an exercise price equal to the fair market value of the Company’s common stock based on the closing price of the Company’s common stock on each date of grant and will be subject to the terms of a nonqualified stock option agreement (the “Canute NQSO Agreement”). Such options will vest in full upon the Company’s receipt of approval from the FDA for the Company’s BLA resubmission for sacituzumab govitecan for the treatment of patients with mTNBC who have received at least two prior therapies for metastatic disease under the PDUFA. The Company and Mr. Canute entered into a letter agreement (the “Canute Letter Agreement”) to memorialize his appointment as the Company’s Executive Director, and the Initial Canute Compensation. The Canute Letter Agreement may be terminated by either party at any time upon written notice to the other party. During the year ended December 31, 2019 , the Company paid Mr. Canute $0.4 million for such services. On November 19, 2019, pursuant to the Plan, the Board of Directors approved a stock option grant to Behzad Aghazadeh, Executive Chairman of the Board of Directors of the Company, to purchase 150,000 shares of the Company's common stock (the "Performance-Based Option") for certain duties performing this role; including providing consulting and advisory services to the Company. The Performance-Based Option will be a nonqualified stock option and one third vested upon FDA acceptance of the BLA resubmission in December 2019, and two thirds shall vest upon approval from the FDA for the Company’s BLA for sacituzumab govitecan.

Collaboration Agreements

Collaboration Agreements	12 Months Ended
	Dec. 31, 2019
Collaboration Agreement
Collaboration Agreement	Collaboration Agreements AstraZeneca/MedImmune In June 2018, we entered into a clinical collaboration with AstraZeneca PLC ("AstraZeneca") and its global biologics research and development arm, MedImmune, to evaluate in Phase 1/2 studies the safety and efficacy of combining AstraZeneca’s Imfinzi ® (durvalumab), a human monoclonal antibody directed against programmed cell death ligand 1 ("PD-L1"), with sacituzumab govitecan as a treatment of patients with triple-negative breast cancer (“TNBC”) and urothelial cancer ("UC"), which was broadened in October 2018 to include second-line metastatic non-small cell lung cancer ("NSCLC"). Part one of the two-part Phase 1/2 studies will be co-funded by the two companies. Immunomedics will supply the study drug and AstraZeneca will utilize its existing clinical trial infrastructure to accelerate the enrollment of the sacituzumab govitecan and durvalumab combination. The trial design allows for rapid transition into randomized Phase 2 studies should the first part of these studies show promising data and the companies agree to proceed based on efficacy and safety results obtained. GBG Forschungs GmbH In September 2019, we entered into a clinical collaboration with the German Breast Group Forschungs-GmbH ("GBG"), Neu-Isenburg, Germany, to develop sacituzumab govitecan as a treatment for newly-diagnosed breast cancer patients who do not achieve a pathological complete response ("pCR") following standard neoadjuvant therapy. The multinational, post-neoadjuvant Phase 3 SASCIA study developed by GBG will be conducted under the sponsorship of GBG. Approximately 1,200 high-risk patients with newly-diagnosed HER2-negative breast cancer not achieving a pCR following standard neoadjuvant therapy will be randomized to receive either sacituzumab govitecan or treatment of physician’s choice. Primary endpoint is invasive DFS with overall survival, patient reported outcome/quality of life, circulating tumor DNA clearance, and safety serving as secondary endpoints. Under the terms of the agreement, GBG is eligible to receive up to €33.0 million in potential clinical and regulatory milestone payments over a span of approximately six years , of which €0.5 million was paid during the year ended December 31, 2019 .

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2019
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies a. Legal Matters Arbitration of Disputed Matters: On January 15, 2019, the Company received an Arbitrator’s Findings of Fact and Conclusions of Law and Final Award (the “Final Award”) in the arbitration matter in which Dr. David M. Goldenberg, the Company’s former Chief Scientific Officer, Chief Patent Officer and Chairman of the Company’s Board of Directors, claimed entitlement to certain equity awards and severance payments, and Dr. Goldenberg and Ms. Cynthia Sullivan, a former director of the Company and former President and Chief Executive Officer, claimed rights to certain bonus payments. The Final Award (i) denied Dr. Goldenberg’s claim that he was entitled to an award of 1.5 million restricted stock units, (ii) denied each of Dr. Goldenberg’s and Ms. Sullivan’s claims that they were entitled to certain discretionary cash bonuses relating to the Company’s 2017 fiscal year, and (iii) granted Dr. Goldenberg an award of approximately $1.0 million relating to certain claimed severance payments which was paid in March 2019. The arbitration took place pursuant to the Delaware Rapid Arbitration Act. Although the Delaware Rapid Arbitration Act permits challenges to arbitration awards in limited circumstances, pursuant to that certain stipulation and agreement of settlement, compromise, and release dated November 2, 2017, the Company, Dr. Goldenberg and Ms. Sullivan agreed that the Final Award would be the sole and exclusive final and binding remedy between and among the parties with respect to the matters disputed in the arbitration. Stockholder Complaints: Class Action Stockholder Federal Securities Cases Two purported class action cases were filed in the United States District Court for the District of New Jersey; namely, Fergus v. Immunomedics, Inc., et al., filed June 9, 2016; and Becker v. Immunomedics, Inc., et al., filed June 10, 2016. These cases arise from the same alleged facts and circumstances and seek class certification on behalf of purchasers of our common stock between April 20, 2016 and June 2, 2016 (with respect to the Fergus matter) and between April 20, 2016 and June 3, 2016 (with respect to the Becker matter). These cases concern the Company’s statements in press releases, investor conference calls, and filings with the U.S. Securities and Exchange Commission (the "SEC") beginning in April 2016 that the Company would present updated information regarding its IMMU-132 breast cancer drug at the 2016 American Society of Clinical Oncology (“ASCO”) conference in Chicago, Illinois. The complaints allege that these statements were false and misleading in light of June 2, 2016 reports that ASCO had canceled the presentation because it contained previously reported information. The complaints further allege that these statements resulted in artificially inflated prices for our common stock, and that the Company and certain of its officers are thus liable under Sections 10(b) and 20(a) of the Securities Exchange Act of 1934, as amended (the "Exchange Act"). An order of voluntary dismissal without prejudice was entered on November 10, 2016 in the Becker matter. An order granting motion to consolidate cases, appoint lead plaintiff, and approve lead and liaison counsel was entered on February 7, 2017 in the Fergus matter. A consolidated complaint was filed on October 4, 2017. The Company filed a motion to dismiss the consolidated complaint on January 26, 2018. On March 31, 2019, the court granted the Company's motion to dismiss, without prejudice, and left plaintiffs with the ability to file an amended complaint within thirty (30) days. Counsel for the Company has consented to an extension of time for plaintiffs to file the proposed amended complaint for an additional thirty (30) days. On May 30, 2019, plaintiffs filed an amended complaint alleging many of the same allegations that were set forth in the previously filed complaints, and the Company has filed a motion to dismiss. A third purported class action case was filed in the United States District Court for the District of New Jersey; namely, Odeh v. Immunomedics, Inc., et al., filed December 27, 2018. The complaint in this action alleges that the Company failed to disclose the results of observations made by the FDA during an inspection of the Company’s manufacturing facility in Morris Plains, New Jersey in August 2018. The complaint alleges that Immunomedics misled investors by failing to disclose the Form 483 inspection report issued by the FDA which set forth the observations of the FDA inspector during the inspection. Such observations purportedly included, inter alia, manipulated bioburden samples, misrepresentation of an integrity test procedure in the batch record, and backdating of batch records. The complaint further alleges that the Company’s failure to disclose the Form 483 resulted in an artificially inflated price for our common stock, and that the Company and certain of its officers are thus liable under Sections 10(b) and 20(a) of the Exchange Act. On February 8, 2019, a purported class action case was filed in the United States District Court for the District of New Jersey; namely, Choi v. Immunomedics, Inc., et al. The complaint asserts violations of the federal securities laws based on claims that the Company violated the federal securities laws by making alleged misstatements in various press releases and securities filings from February 8, 2018 to November 7, 2018 and by failing to disclose the substance of its interactions with the FDA in connection with the Company's submission of its BLA for sacituzumab govitecan. Motions for the appointment of a lead plaintiff and lead counsel and to consolidate the Odeh and Choi actions were granted on September 10, 2019. Pursuant to a scheduling order entered by the court on October 7, 2019, the plaintiffs filed an amended complaint on November 18, 2019. The Company filed a motion to dismiss the consolidated, amended complaint on January 17, 2020. The motion has a return date of April 20, 2020. On April 8, 2019, a putative stockholder of the Company filed a derivative action purportedly on behalf of the Company and against the Company’s board of directors and certain Company current and former officers, in the Superior Court of New Jersey, Law Division (Morris County); namely, Crow v. Aghazadeh, et al. The Crow complaint alleges that the individual defendants breached their fiduciary duties and committed other violations of law based on the same core allegations in the Odeh and Choi actions. The Crow complaint was served on the Company and other defendants on July 18, 2019. On August 13, 2019, the parties submitted to the court a stipulation and proposed order to stay the action until either the entry of an order denying all motions to dismiss the now-consolidated federal actions or the entry of an order dismissing the federal actions with prejudice. That stipulation is currently pending court approval. Stockholder Claim in the Court of Chancery of the State of Delaware On February 13, 2017, venBio commenced an action captioned venBio Select Advisor LLC v. Goldenberg, et al., C.A. (Del. Ch.) (the “venBio Action”), alleging that Company’s Board breached their fiduciary duties when the Board (i) amended the Company’s Amended and Restated By-laws (the “By-Laws”) to call for a plurality voting regime for the election of directors instead of majority voting, and providing for mandatory advancement of attorneys’ fees and costs for the Company’s directors and officers, (ii) rescheduled the Company’s 2016 Annual Meeting of Stockholders (the “2016 Annual Meeting”) from December 14, 2016 to February 16, 2017, and then again to March 3, 2017, and (iii) agreed to the proposed Licensing Transaction with Seattle Genetics. venBio also named Seattle Genetics as a defendant and sought an injunction preventing the Company from closing the licensing transaction with Seattle Genetics. On March 6, 2017, venBio amended its complaint, adding further allegations. The Court of Chancery entered a temporary restraining order on March 9, 2017, enjoining the closing of the Licensing Transaction. venBio amended its complaint a second time on April 19, 2017, this time adding Greenhill & Co. Inc. and Greenhill & Co. LLC (together “Greenhill”), the Company’s financial advisor on the Licensing Transaction, as an additional defendant. On May 3, 2017, venBio and the Company and individual defendants Dr. Goldenberg, Ms. Sullivan and Mr. Brian A. Markison, a director of the Company (collectively, the “Individual Defendants”) entered into the Initial Term Sheet. On June 8, 2017, venBio the Company and Greenhill entered into the Greenhill Term Sheet. On February 9, 2018, the Court of Chancery approved the Settlement, and entered an order and partial judgment releasing all claims that were asserted by venBio against the Individual Defendants and Greenhill in the venBio Action and awarding venBio fees and expenses. On May 24, 2018 the remaining parties to the venBio Action participated in a mediation of the claims against Geoff Cox, Robert Forrester, Bob Oliver, and Jason Aryeh (the "Remaining Defendants"). The mediation was unsuccessful. The Remaining Defendants filed submitted motions to dismiss the claims against them in the venBio Action. On March 18, 2019, venBio amended its complaint, adding further allegations. The Remaining Defendants filed a motion to dismiss the claims against them on May 1, 2019. The Court of Chancery held oral arguments for the motion to dismiss on November 13, 2019 and following arguments, denied Defendants' motion to dismiss on that same date. The parties are now engaged in discovery activities. Insurance Coverage Arbitration: The Company has initiated an arbitration with two of its management liability insurers: Starr Indemnity & Liability Company (“Starr”), and Liberty Insurance Underwriters Inc. (“Liberty”) (collectively, “Insurers”). The arbitration arises from the 2015 Insurers’ refusal to cover $3.4 million in attorneys’ fees and expenses paid to venBio pursuant to a December 1, 2017, settlement agreement between venBio, the Company, Dr. Goldenberg, Ms. Sullivan, Mr. Markison, and Greenhill to partially settle the venBio Action and fully settle the Federal Action and the Delaware Section 225 Action (the “venBio Fee Award”). The Insurers argue that the venBio Fee Award does not satisfy their policies’ definitions of covered “loss” because the policies only cover defense costs incurred by the Company. The Company counters that the venBio Fee Award is a covered settlement, not a claim for defense costs. Insurers also argue that they have no obligation to pay any defense costs or settlement incurred in the Federal Action or 225 Action because Immunomedics initiated those lawsuits. The Company’s position is that the Federal Action and 225 Action were defensive in nature and therefore covered because they were initiated to further the defense of the venBio Action. Additionally, Insurers argue the venBio Fee Award is not covered because the Company was required to obtain Insurers’ consent to enter into a binding term sheet in the venBio Action and to agree to pay the venBio Fee Award and that the Company failed to do so. The Company takes the position that Insurers at all times were aware of the developments in the venBio Action, that they sought consent to enter into the settlement, and that Insurers cannot show they were prejudiced by an any alleged failure to obtain Insurers’ consent. Liberty also contends that the Company’s insurance claim is not covered by Liberty’s 2015-16 insurance policy and should be covered by another company’s policy in a later policy period. The Company takes the position that the policies treat the venBio Action as a related claim to the Fergus v. Immunomedics class action stockholder federal securities case, which was filed in 2016 and that because of the similar allegation in the venBio Action and Fergus, the policies deem the venBio Action claim to be made at the same time as Fergus and covered by the 2015-16 policies. In the arbitration, Starr contends it will have the benefit of any finding that the claim is covered in a later policy period, even though Starr had agreed with the Company’s position prior to the arbitration. In the event Insurers prevail on their argument that the venBio Fee Award is covered by a subsequent policy year, the Company will pursue coverage under its other insurance policies. Starr is presently advancing the costs to defend the remaining claims in the venBio Action, i.e., those against the Company as Nominal Defendant and individual defendants Aryeh, Cox, Forrester, and Oliver. However, all Insurers have reserved their rights to contest coverage for any potential settlement of those claims. b. Other Matters Immunomedics is also a party to various claims and litigation arising in the normal course of business. c. Leases Our operating lease assets primarily represent manufacturing and research and development facilities, warehouses, and offices. Our finance leases primarily represent computer equipment and are not significant. For the year ended December 31, 2019 , cash payments against operating lease liabilities totaled $1.3 million . The discount rate used to determine the net present value of the leases at inception was 11.0% . This is the incremental borrowing rate that represents the rate of interest that the Company would expect to pay to borrow an amount equal to the lease payments under similar terms. Our leases both share a remaining lease term of 11.8 years , some of which may include options to extend the leases further. The Company considers these options in determining the lease term used to establish the right-of-use assets and lease liabilities. Supplemental consolidated balance sheet information related to leases are as follows (in thousands): Operating leases: December 31, 2019 Operating lease right-of-use assets, net $ 8,105 Current portion of lease liabilities $ 337 Non-current portion of lease liabilities $ 9,965 Total operating lease liabilities $ 10,302 Weighted average remaining lease term (years) 11.8 Weighted average discount rate 11.0 % Operating lease right-of-use asset is a component of property and equipment on the consolidated balance sheet. The non-current portion of lease liabilities is a component of other long-term liabilities on the consolidated balance sheet. Supplemental cash flow information related to leases are as follows (in thousands): Year Ended December 31, 2019 Non-cash lease expense $ 264 Change in operating lease liabilities $ 186 Maturities of lease liabilities as of December 31, 2019 are as follows (in thousands): Year 1 $ 1,453 Year 2 1,465 Year 3 1,523 Year 4 1,531 Year 5 1,567 Thereafter 11,333 Total lease payments 18,872 Less imputed interest (8,570 ) Total $ 10,302 Operating lease expense was approximately $1.4 million , $0.7 million , $1.3 million , and $0.9 million for the year ended December 31, 2019 , the transition period ended December 31, 2018 and fiscal years ended June 30, 2018, and 2017, respectively. d. Purchase Obligations We have several commitments primarily to purchase commercial manufacturing services including minimum purchase commitments related to product supply contracts and e-sourcing software totaling $90.0 million in 2020, $59.8 million in 2021, $40.8 million in 2022, $40.8 million in 2023, $33.0 million in 2024 and $33.0 million thereafter. e. License On April 4, 2018, we entered into a license agreement with The Scripps Research Institute ("TSRI"). Pursuant to the license agreement, TSRI granted to us an exclusive, worldwide, sub-licensable, royalty-bearing license to use certain patent rights relating to our ADC sacituzumab govitecan. The license agreement expires on a country-by-country basis on the expiration date of the last to expire licensed patent rights in such country covering a licensed product. The license agreement may be terminated by the mutual written consent of us and TSRI, and TSRI may terminate the license agreement upon the occurrence of certain events, including but not limited to if we do not make a payment due pursuant to the license agreement and fail to cure such non-payment within 30 days after the date of TSRI's written notice of such non-payment. As consideration for the license granted, we made a cash payment of $0.3 million to TSRI. Additionally, we will pay TRSI (i) product development milestone payments that range from the mid-six digit dollar figure to the low-seven digit dollar figure and (ii) royalties on net sales of licensed products in the low-single digit percentage figure range capped at an annual amount. We have agreed to use reasonable efforts to develop and market the licensed products. During the year ended December 31, 2019, we recognized a $0.5 million milestone payment expense. f. Michael Pehl Separation On March 13, 2019, the Company entered into a separation agreement (the “Separation Agreement”) with Michael Pehl, the Company’s former Chief Executive Officer, President and member of the Company’s Board. Mr. Pehl resigned as Chief Executive Officer, President and member of the Company’s Board effective February 23, 2019. Pursuant to the Separation Agreement, Mr. Pehl will receive cash payments of approximately $1.0 million over an eighteen-month period. During the year ended December 31, 2019 , the Company paid approximately $0.5 million to Mr. Pehl, and $0.6 million was accrued for as of December 31, 2019

Defined Contribution Plans

Defined Contribution Plans	12 Months Ended
	Dec. 31, 2019
Retirement Benefits [Abstract]
Defined Contribution Plans	Defined Contribution Plans Eligible employees are able to participate in the Company’s 401(k) plan. Effective January 1, 2019, the Company increased the employer non-discretionary matching contributions in an amount equal to 100% of deferral contributions up to a maximum of 5% of eligible compensation contributed to the 401(k) plan. Company contributions to the 401(k) plan totaled approximately $ 1.9 million for the year ended December 31, 2019, and $0.1 million for the Transition Period and for each of the fiscal years ended June 30, 2018 and 2017.

Quarterly Results of Operations

Quarterly Results of Operations (Unaudited)	12 Months Ended
	Dec. 31, 2019
Quarterly Financial Information Disclosure [Abstract]
Quarterly Results of Operations (Unaudited)	Quarterly Results of Operations (Unaudited) The following table summarizes unaudited quarterly financial data: Three Months Ended ($ in thousands, except for per share amounts) December 31, 2019 September 30, 2019 June 30, 2019 March 31, 2019 Consolidated Statements of Comprehensive Loss Data: Revenues $ 295 $ — $ — $ — Net loss attributable to Immunomedics, Inc. stockholders $ (99,608 ) $ (94,292 ) $ (75,953 ) $ (87,337 ) Loss per common share attributable to Immunomedics Inc. stockholders – (basic and diluted) $ (0.50 ) $ (0.49 ) $ (0.40 ) $ (0.46 ) Weighted average shares used to calculate loss per common share – (basic and diluted) 199,614 191,981 191,745 191,052 Three Months Ended ($ in thousands, except for per share amounts) December 31, 2018 September 30, 2018 June 30, 2018 March 31, 2018 Consolidated Statements of Comprehensive Loss Data: Revenues $ — $ — $ 387 $ 482 Net loss attributable to Immunomedics, Inc. stockholders $ (93,499 ) $ (64,169 ) $ (117,032 ) $ (35,546 ) Loss per common share attributable to Immunomedics Inc. stockholders – (basic and diluted) $ (0.50 ) $ (0.34 ) $ (0.68 ) $ (0.21 ) Weighted average shares used to calculate loss per common share – (basic and diluted) 190,171 186,937 171,124 166,054

Business Overview, Summary of S

Business Overview, Summary of Significant Accounting Polices (Policies)	12 Months Ended
	Dec. 31, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Accounting	Basis of Presentation The consolidated financial statements include the accounts of Immunomedics and its subsidiaries. Noncontrolling interests in consolidated subsidiaries in the consolidated balance sheets represent minority stockholders' proportionate share of the equity (deficit) in such subsidiaries. All intercompany balances and transactions have been eliminated in consolidation. In this Annual Report, the periods presented are the year ended December 31, 2019, the six-month transition period from July 1, 2018 to December 31, 2018 (which we sometimes refer to as the "Transition Period") and our fiscal years ended June 30, 2018 and 2017 (which are referred to as “fiscal 2018,” and "fiscal 2017", as if we had not changed our fiscal year to a calendar year).
Use of Estimates	Use of Estimates The preparation of consolidated financial statements in conformity with United States generally accepted accounting principles 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 consolidated financial statements and the reported amounts of revenues and expenses during the reported period. Actual results could differ from those estimates. The Company’s significant estimates and assumptions relate to stock-based compensation expenses, the fair value for the liability related to sale of future royalties and related interest expense.
Interest Expense on Liability Related to Sale of Future Royalties	Interest Expense on Liability Related to Sale of Future Royalties The Company accounts for the liability related to the sale of future royalties as a debt financing. The Company has a significant continuing involvement in the generation of related royalty streams. The Company accretes this liability and recognizes expected interest expense using the effective interest rate method over the life of the related royalty stream, based on our current estimates of future royalty payments. These estimates include projections the Company makes and projections from outside the Company and involves significant judgment and inherent uncertainties. The Company periodically re-assesses the projections and, to the extent our future projections are greater or less than its previous estimates or the estimated timing of such payments is materially different than its previous estimates, the Company will adjust the effective interest calculation.
Foreign Currencies	Foreign Currencies For our German subsidiary which operates in a local currency environment, income and expense items are translated to United States dollars at the monthly average rates of exchange prevailing during the year, assets and liabilities are translated at year-end exchange rates and equity accounts are translated at historical exchange rates. Translation adjustments are accumulated in a separate component of stockholders' equity in the consolidated balance sheets and the consolidated statements of changes in stockholders’ equity and are included in the determination of comprehensive (loss) income in the consolidated statements of comprehensive loss. Transaction gains and losses are included in the determination of net loss in the consolidated statements of comprehensive loss.
Financial Instruments	Financial Instruments The carrying amount of cash and cash equivalents, prepaid expenses, other current assets and current liabilities approximate fair value due to the short-term maturity of these instruments. The Company considers all highly liquid investments with an original maturity of three months or less when purchased to be cash equivalents.
Marketable Securities	Marketable Securities Marketable securities, all of which are available-for-sale, consist of United States Government sponsored agencies which are carried at fair value, with unrealized gains and losses, net of related income taxes, reported as accumulated other comprehensive loss, except for losses from impairments which are determined to be other-than-temporary. Realized gains and losses and declines in value judged to be other-than-temporary on available-for-sale securities are included in the determination of net loss and are included in interest and other income (net), at which time the average cost basis of these securities are adjusted to fair value. Fair values are based on quoted market prices at the reporting date. Interest and dividends on available-for-sale securities are included in interest and other income (net).
Property, Plant and Equipment	Property and Equipment Property and equipment are stated at cost less accumulated depreciation and amortization. Depreciation expense is computed using the straight-line method over the estimated useful lives of the assets, including leasehold improvements and capital lease assets that are amortized over the shorter of their useful lives or the terms of the respective leases. The Company generally uses the following range of useful lives for its property and equipment categories: leasehold improvements— 7 to 10 years ; computer equipment— 5 years ; machinery and equipment— 5 to 10 years ; and furniture and fixtures— 10 years . Depreciation expense includes amortization of assets related to capital leases. The Company charges repairs and maintenance costs to expense as incurred.
Concentration of Credit Risk	Concentration of Credit Risk
Revenue Recognition	Revenue Recognition Pursuant to Topic 606, we recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. To achieve this core principle, Topic 606 includes provisions within a five step model that includes i) identifying the contract with a customer, ii) identifying the performance obligations in the contract, iii) determining the transaction price, iv) allocating the transaction price to the performance obligations, and v) recognizing revenue when, or as, an entity satisfies a performance obligation. At contract inception, we assess the goods or services promised within each contract and assess whether each promised good or service is distinct and determine those that are performance obligations. We then recognize as revenue the amount of the transaction price that is allocated to the respective performance obligation when the performance obligation is satisfied.
Research and Development Costs	Research and Development Costs Research and development costs are expensed as incurred. Costs incurred for clinical trials for patients and investigators are expensed as services are performed in accordance with the agreements in place with the institutions. Research and development costs include salaries and benefits, costs associated with producing biopharmaceutical compounds, laboratory supplies, the costs of conducting clinical trials, and facilities costs. In addition, the Company uses clinical research organizations and contract manufacturing operations to outsource portions of our research and development activities.
Treasury Shares	Treasury Shares The Company records treasury stock at the cost to acquire it and includes treasury stock as a component of Stockholders’ Equity. In determining the cost of the treasury shares when either sold or issued, the Company uses the first-in, first-out method ("FIFO"). If the proceeds from the sale of the treasury shares are greater than the cost of the shares sold, the excess proceeds are recorded as additional paid-in capital. If the proceeds from the sale of the treasury shares are less than the original cost of the shares sold, the excess cost reduces any additional paid-in capital arising from previous sales of treasury shares for that class of stock.
Fair Value Measurements	Fair Value Measurements The Company categorizes its financial instruments measured at fair value into a three-level fair value hierarchy that prioritizes the inputs used in determining the fair value of the asset or liability. The three levels of the fair value hierarchy are as follows: • Level 1 - Financial instruments whose values are based on unadjusted quoted prices for identical assets or liabilities in an active market which the company has the ability to access at the measurement date (examples include active exchange-traded securities and most United States Government and agency securities). • Level 2 - Financial instruments whose value are based on quoted market prices in markets where trading occurs infrequently or whose values are based on quoted prices of instruments with similar attributes in active markets. • Level 3 - Financial instruments whose values are based on prices or valuation techniques that require inputs that are both unobservable and significant to the overall fair value measurement. These inputs reflect management's own assumptions about the assumptions a market participant would use in pricing the asset. The Company’s financial instruments consist of cash and cash equivalents, marketable securities, prepaid expenses, other current assets, accounts payable and accrued expenses, convertible senior notes, liabilities related to the sale of future royalties and Convertible Senior Notes. The carrying amount of prepaid expenses, other current assets, accounts payable and accrued expenses and certain other liabilities are generally considered to be representative of their respective fair values because of the short-term nature of those instruments.
Income Taxes	Income Taxes The Company uses the asset and liability method to account for income taxes, including the recognition of deferred tax assets and deferred tax liabilities for the anticipated future tax consequences attributable to differences between financial statements amounts and their respective tax bases. The Company reviews its deferred tax assets for recovery. A valuation allowance is established when the Company believes that it is more likely than not that its deferred tax assets will not be realized. Changes in valuation allowances from period to period are included in the Company’s tax provision in the period of change. The Company has recorded a full valuation allowance against its net deferred tax assets as of December 31, 2019 and 2018 . The Tax Cuts and Jobs Act (the "Act") was signed into law on December 22, 2017. Among its numerous changes to the Internal Revenue Code, the Act reduces United States corporate rates from 35% to 21%. Additionally, the Act limits the use of net operating loss carry backs, however any future net operating losses will instead be carried forward indefinitely. Only 80% of current income will be able to be offset with a net operating loss carryforward, with the remainder of the net operating loss continuing to carry forward. As a result of the reduction in the U.S. corporate income tax rate, the Company revalued its ending net deferred tax assets as of June 30, 2018, which resulted in a provisional expense of $59.5 million
Net Loss Per Share Allocable to Common Stockholders	Net Loss Per Share Allocable to Common Stockholders Net loss per basic and diluted common share allocable to common stockholders is based on the net loss for the relevant period, divided by the weighted-average number of common shares outstanding during the period. For purposes of the diluted net loss per common share calculations, the exercise or exchange of all potential common shares is not included because their effect would have been anti-dilutive, due to the net loss recorded for the year ended December 31, 2019 , the Transition Period and fiscal years ended June 2018, and 2017, respectively. The common stock equivalents excluded from the earnings per share calculation are 8.2 million , 6.7 million , 10.0 million , and 66.1 million for the year ended December 31, 2019 , the Transition Period and the fiscal years ended June 2018, and 2017, respectively.
Net Comprehensive Loss	Net Comprehensive Loss Net comprehensive loss consists of net loss, unrealized gain (loss) on available for sale securities and foreign exchange translation adjustments and is presented in the consolidated statements of comprehensive loss.
Stock-Based Compensation	Stock-Based Compensation The Company utilizes stock-based compensation in the form of stock options, stock appreciation rights, stock awards, stock unit awards, performance shares, cash-based performance units and other stock-based awards, each of which may be granted separately or in tandem with other awards. The grant-date fair value of stock awards is based upon the underlying price of the stock on the date of grant. The grant-date fair value of stock option awards must be determined using an option pricing model. Option pricing models require the use of estimates and assumptions as to (a) the expected term of the option, (b) the expected volatility of the price of the underlying stock and (c) the risk-free interest rate for the expected term of the option. The Company uses the Black-Scholes option pricing formula for determining the grant-date fair value of such awards. The fair value of option awards that vest based on achievement of certain market conditions are determined using a Monte Carlo simulation technique. The expected term of the option is based upon the contractual term and expected employee exercise and expected post-vesting employment termination behavior. The expected volatility of the price of the underlying stock is based upon the historical volatility of the Company’s stock computed over a period of time equal to the expected term of the option. The risk-free interest rate is based upon the implied yields currently available from the United States Treasury yield curve in effect at the time of the grant. Forfeitures are recorded as incurred.
Recently Issued Accounting Pronouncements	Recently Issued Accounting Pronouncements Accounting Pronouncements adopted during the year The Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2019-01, “Leases Topic 842,” requiring entities to recognize assets and liabilities on the balance sheet for all leases, with certain exceptions. Topic 842 allows for a modified retrospective application and is effective as of the first quarter of 2019. Entities are allowed to apply the new guidance using a modified retrospective approach at the beginning of the year in which new lease standard is adopted, rather than to the earliest comparative period presented in their financial statements. The modified retrospective approach includes a number of optional practical expedients that entities may elect to apply. We elected the modified retrospective approach under the new guidance and elected the available practical expedients on adoption. Upon adoption, we recognized additional operating lease liabilities of $8.4 million with a corresponding right-of-use assets of $8.4 million based on the present value of the remaining lease payments under existing operating leases. As of December 31, 2018, we had $2.1 million in deferred charges related to our real estate leases that were recorded against the lease liability asset as part of the transition, resulting in $10.5 million included in other long-term liabilities on our consolidated balance sheets. In addition, the new guidance resulted in additional lease-related disclosures in the footnotes to our consolidated financial statements. Our leasing portfolio is comprised entirely of operating leases, and we do not recognize right-of-use assets or related lease liabilities with a lease term of twelve months or less on our consolidated balance sheets. Adoption of Topic 842 has required changes to our business processes and controls to comply with the provisions of the standard. Refer to Note 14 "Commitments and Contingencies" for additional information. In June 2018, the FASB issued ASU 2018-07, "Compensation-Stock Compensation," to improve the usefulness of information provided to users of financial statements while reducing cost and complexity in financial reporting and provide guidance aligning the measurement and classification for share-based payments to nonemployees with the guidance for share-based payments to employees. Under the guidance, the measurement of equity-classified nonemployee awards will be fixed at the grant date. This standard is effective for fiscal years beginning after December 15, 2018, and interim periods within those annual periods. Early adoption is permitted, but no earlier than an entity's adoption date of ASU 2014-09, “Revenue from Contracts with Customers (Topic 606).” We adopted ASU 2018-07 during the first quarter of 2019 and the adoption did not have a material impact to our consolidated financial statements. Accounting Pronouncements yet to be adopted In November 2018, the FASB issued ASU 2018-18, "Collaborative Arrangements (Topic 808): Clarifying the Interaction between Topic 808 and Topic 606," to clarify when ASC 606 should be used for collaborative arrangements when the counterparty is a customer. The guidance precludes an entity from presenting consideration from a transaction in a collaborative arrangement as revenue from contracts with customers if the counterparty is not a customer for that transaction. The guidance is effective for public business entities in fiscal years beginning after December 15, 2019, and interim periods therein. Early adoption is permitted to entities that have adopted ASC 606. We are currently assessing the impact of ASU 2018-18. In August 2018, the FASB issued ASU 2018-13, "Fair Value measurement (Topic 820): Disclosure Framework - Changes to the Disclosure Requirements for Fair Value Measurement," to no longer require public companies to disclose transfers between Level 1 and Level 2 of the fair value hierarchy, and to require disclosure about the range and weighted average used to develop significant unobservable inputs for Level 3 fair value measurements. The guidance is effective for fiscal years beginning after December 15, 2019, and for interim periods within those fiscal years. Entities are permitted to early adopt either the entire standard or only the provisions that eliminate or modify the requirements. We are currently assessing the impact of ASU 2018-13.

Marketable Securities (Tables)

Marketable Securities (Tables)	12 Months Ended
	Dec. 31, 2019
Investments, Debt and Equity Securities [Abstract]
Schedule of Available-for-sale Securities	The following table summarizes the marketable securities held as of December 31, 2019 and 2018 (in thousands): December 31, 2019 Amortized Cost Gross Unrealized Gain Gross Unrealized (Loss) Fair Value U.S. Government Sponsored Agencies $ 4,941 $ — $ (391 ) $ 4,550 December 31, 2018 Amortized Cost Gross Unrealized Gain Gross Unrealized (Loss) Fair Value U.S. Government Sponsored Agencies $ 4,941 $ — $ — $ 4,941

Debt (Tables)

Debt (Tables)	12 Months Ended
	Dec. 31, 2019
Debt Disclosure [Abstract]
Schedule of allocation of fair value to liability	The Company allocated the transaction consideration on a relative fair value to the liability and common stock in accordance with ASC 470-10 as follows (in thousands): Units of Accounting: Allocated Consideration Liability related to sale of future royalties $ 182,216 Common stock 67,784 $ 250,000
Schedule of deferred revenue, by arrangement	The following table shows the activity within the liability related to sale of future royalties during the year ended December 31, 2019 , the Transition Period and at the fiscal year ended June 30, 2018 (in thousands): Liability related to sale of future royalties at January 7, 2018 $ 182,216 Interest expense recognized 19,791 Carrying value of liability related to sale of future royalties at June 30, 2018 $ 202,007 Interest expense recognized 19,288 Carrying value of liability related to sale of future royalties at December 31, 2018 $ 221,295 Interest expense recognized 39,929 Carrying value of liability related to sale of future royalties at December 31, 2019 (includes current portion of $3,455) $ 261,224

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2019
Share-based Payment Arrangement [Abstract]
Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions	We estimated the fair value of options granted using a Black-Scholes option pricing model with the following assumptions: Year Ended December 31, 2019 Transition Period December 31, 2018 Fiscal Years Ended June 30, 2018 2017 Expected dividend yield —% —% —% —% Expected option term (years) 4.52 4.76 4.84 5.04 Expected stock price volatility 71% 69% 70% 63% Risk-free interest rate 1.39% - 2.58% 2.69% - 3.06% 1.72% - 2.89% 1.16% - 2.15%
Share-based Compensation, Stock Options, Activity	The following table summarizes all stock option activity for the ended December 31, 2019 : Options (in thousands) Weighted Average Exercise Price Per Option Weighted Average Remaining Contractual Term (Years) Aggregate Intrinsic Value (in thousands) Options outstanding, January 1, 2019 4,757 $ 14.30 5.42 $ 18,618 Changes during the year: Granted 3,614 15.46 Exercised (1,207 ) 3.17 Expired or forfeited (1,263 ) 17.78 Options outstanding, end of year 5,901 $ 16.54 5.90 $ 30,145 Vested as of December 31, 2019 1,150 $ 14.72 4.61 $ 8,276 The following table summarizes all stock option activity for the Transition Period ended December 31, 2018 : Options (in thousands) Weighted Average Exercise Price Per Option Weighted Average Remaining Contractual Term (Years) Aggregate Intrinsic Value (in thousands) Options outstanding, July 1, 2018 3,549 $ 7.58 4.43 $ 57,123 Changes during the year: Granted 2,002 22.54 Exercised (706 ) 3.71 Expired or forfeited (88 ) 15.57 Options outstanding, end of year 4,757 $ 14.30 5.42 $ 18,618 Vested as of December 31, 2018 1,504 $ 4.23 3.41 $ 15,098
Schedule of Share-based Compensation, Restricted Stock and Restricted Stock Units Activity	Information regarding the Company's RSU's for the year ended December 31, 2019 is as follows: Non-Vested Restricted Stock Units Share Equivalent (in thousands) Weighted Average Grant Date Fair Value Non-vested at January 1, 2019 15 $ 14.29 Changes during the period: Restricted Units Granted 58 12.93 Vested/Exercised (15 ) 14.29 Forfeited — — Non-vested at December 31, 2019 58 $ 12.93 Information regarding the Company's RSU's for the Transition Period ended December 31, 2018 is as follows: Non-Vested Restricted Stock Units Share Equivalent (in thousands) Weighted Average Grant Date Fair Value Non-vested at July 1, 2018 1,535 $ 2.83 Changes during the period: Restricted Units Granted 15 14.29 Vested/Exercised (35 ) 8.46 Forfeited (1,500 ) 2.28 Non-vested at December 31, 2018 15 $ 14.29
Schedule of Share-based Compensation, Performance Stock and Performance Stock Units Activity	The following table summarizes the Company's performance-based stock option activity for the year ended December 31, 2019 is as follows: Options (in thousands) Weighted Average Exercise Price Per Option Weighted Average Remaining Contractual Term (Years) Aggregate Intrinsic Value (in thousands) Options outstanding, January 1, 2019 538 $ 13.09 6.04 $ 772 Changes during the year: Granted 800 17.18 Exercised — — Expired or forfeited (501 ) 13.05 Options outstanding, end of year 837 $ 17.03 6.26 $ 3,456 Vested as of December 31, 2019 50 $ 18.74 6.88 $ 121 The following table summarizes the Company's performance-based stock option activity for the Transition Period ended December 31, 2018 is as follows: Options (in thousands) Weighted Average Exercise Price Per Option Weighted Average Remaining Contractual Term (Years) Aggregate Intrinsic Value (in thousands) Options outstanding, July 1, 2018 538 $ 13.09 6.54 $ 5,688 Changes during the year: Granted — — Exercised — — Expired or forfeited — — Options outstanding, end of year 538 $ 13.09 6.04 $ 772 Vested as of December 31, 2018 38 $ 11.86 5.94 $ 91

Estimated Fair Value of Finan_2

Estimated Fair Value of Financial Instruments (Tables)	12 Months Ended
	Dec. 31, 2019
Fair Value Disclosures [Abstract]
Schedule of Financial Instruments Recorded on Condensed Consolidated Balance Sheets	Cash Equivalents and Marketable Securities ($ in thousands) As of December 31, 2019 Level 1 Level 2 Level 3 Total Money Market Funds Note (a) $ 550,788 $ — $ — $ 550,788 Marketable Securities: U.S. Government Sponsored Agencies 4,550 — — 4,550 Total $ 555,338 $ — $ — $ 555,338 ($ in thousands) As of December 31, 2018 Level 1 Level 2 Level 3 Total Money Market Funds Note (a) $ 326,239 $ — $ — $ 326,239 Marketable Securities: U.S. Government Sponsored Agencies 4,941 — — 4,941 Total $ 331,180 $ — $ — $ 331,180 (a) The money market funds noted above are included in cash and cash equivalents.
Schedule of Carrying Amounts and Estimated Fair Values (Level 2) of Debt Instruments	The carrying amounts and estimated fair values (Level 2) of debt instruments are as follows (in thousands): As of December 31, 2019 As of December 31, 2018 Carrying Amount Estimated Fair Value Carrying Amount Estimated Fair Value Convertible Senior Notes $ 7,106 $ 28,900 $ 7,055 $ 20,100

Property and Equipment (Tables)

Property and Equipment (Tables)	12 Months Ended
	Dec. 31, 2019
Property, Plant and Equipment [Abstract]
Summary of Property and Equipment	Property and equipment consisted of the following as of December 31, (in thousands): 2019 2018 Machinery and equipment $ 14,331 $ 16,048 Leasehold improvements 11,535 6,365 Right-of-use asset 8,368 — Furniture and fixtures 1,190 291 Computer equipment 2,596 1,850 Construction in progress 2,667 3,231 40,687 27,785 Accumulated depreciation and amortization (7,925 ) (4,316 ) $ 32,762 $ 23,469

Accounts Payable and Accrued _2

Accounts Payable and Accrued Expenses (Tables)	12 Months Ended
	Dec. 31, 2019
Payables and Accruals [Abstract]
Schedule of Accounts Payable and Accrued Expenses	Accounts payable and accrued expenses consisted of the following as of December 31, (in thousands): 2019 2018 (a) Trade accounts payable $ 37,758 $ 20,125 Accrued contract manufacturing expenses 11,663 — Accrued employee related expenses 7,403 315 Clinical trial accruals 2,225 5,114 Executive severance liabilities 561 2,198 Miscellaneous other current liabilities 1,250 3,970 $ 60,860 $ 31,722 (a) Certain 2018 amounts have been reclassified to conform with current year presentation.

Accumulated Other Comprehensi_2

Accumulated Other Comprehensive (Loss) Income (Tables)	12 Months Ended
	Dec. 31, 2019
Equity [Abstract]
Components of Accumulated Other Comprehensive (Loss) Income	The components of accumulated other comprehensive (loss) income were as follows (in thousands): Currency Translation Adjustments Net Unrealized Gains (Losses) on Available-for-Sale Securities Accumulated Other Comprehensive (Loss) Income Balance at June 30, 2016 $ (172 ) $ 40 $ (132 ) Other comprehensive loss before reclassifications (62 ) (125 ) (187 ) Amounts reclassified from accumulated other comprehensive income (a) — 16 16 Net other comprehensive loss for the year (62 ) (109 ) (171 ) Balance at June 30, 2017 (234 ) (69 ) (303 ) Other comprehensive income (loss) before reclassifications (105 ) 55 (50 ) Amounts reclassified from accumulated other comprehensive income (a) — — — Net other comprehensive (loss) income for the year (105 ) 55 (50 ) Balance at June 30, 2018 (339 ) (14 ) (353 ) Other comprehensive income (loss) before reclassifications (8 ) 10 2 Amounts reclassified from accumulated other comprehensive income (a) — — — Net other comprehensive (loss) income for the year (8 ) 10 2 Balance at December 31, 2018 (347 ) (4 ) (351 ) Other comprehensive loss before reclassifications (21 ) (391 ) (412 ) Amounts reclassified from accumulated other comprehensive income (a) 195 — 195 Net other comprehensive (loss) income for the year 174 (391 ) (217 ) Balance at December 31, 2019 $ (173 ) $ (395 ) $ (568 ) (a) For the year ended December 31, 2019 , the Transition Period ended December 31, 2018, and the fiscal years ended June 30, 2018 and 2017, $0.2 million , $0 , $0 , and $16 thousand , respectively, were reclassified from accumulated other comprehensive (loss) income to interest and other income.

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Schedule of Expense for Income Taxes	Income tax expense for income taxes is as follows (in thousands): Year Ended December 31, 2019 Transition Period Ended December 31, 2018 Fiscal Year Ended June 30, 2018 2017 Federal Current $ — $ — $ — $ — Deferred — — — — Total Federal — — — — State Current — — 2 1 Deferred — — — — Total State — — 2 1 Foreign Current — — 154 19 Deferred — — — — Total Foreign — — 154 19 Total income tax expense $ — $ — $ 156 $ 20
Schedule of Reconciliation of Statutory Tax Rates and Effective Tax Rates	A reconciliation of the statutory tax rates and the effective tax rates for the year ended December 31, 2019 , the transition period ended December 31, 2018 and fiscal years ended June 30, 2018 and 2017 is as follows: Year Ended December 31, 2019 Transition Period Ended December 31, 2018 Fiscal Year Ended June 30, 2018 2017 Statutory rate (21.0 )% (21.0 )% (28.0 )% (34.0 )% Foreign income tax — % — % — % — % Change in valuation allowance 29.9 % 34.4 % 21.1 % 21.9 % State income taxes, (net of federal tax benefit) (7.5 )% (8.8 )% (4.3 )% (4.8 )% Permanent differences, (primarily warrant-related expenses) (1.4 )% (4.2 )% 11.3 % 15.3 % Other — % (0.4 )% — % 1.6 % Effective rate — % — % 0.1 % — %
Schedule of Tax Effects of Temporary Differences in Deferred Tax Assets	The tax effects of temporary differences that give rise to significant portions of the Company’s deferred tax assets and liabilities as of December 31, (in thousands): 2019 2018 Deferred tax assets: NOL carryforwards $ 203,928 $ 132,841 Research and development credits 28,535 23,118 Liability related to sale of future royalties 49,228 49,217 Deferred revenue 18,286 — Disallowed interest expense 13,474 — Other 5,807 3,088 Total 319,258 208,264 Valuation allowance (317,828 ) (206,397 ) Net deferred assets $ 1,430 $ 1,867 Deferred tax liabilities: Property and equipment $ (1,430 ) $ (1,867 ) Net deferred assets and liabilities $ — $ —
Summary of Unrecognized Tax Benefits	The change in unrecognized tax benefits are presented below (in thousands): Year Ended December 31, 2019 Transition Period Ended December 31, 2018 Change in unrecognized tax benefits Balance at beginning of year $ 2,521 $ — Gross increases related to current period tax positions — — Gross increases related to prior periods tax positions — 2,521 Gross decreases in tax positions — — Expiration of the statute of limitations — — Balance at end of year $ 2,521 $ 2,521

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2019
Commitments and Contingencies Disclosure [Abstract]
Schedule of Supplemental Lease Information	Supplemental consolidated balance sheet information related to leases are as follows (in thousands): Operating leases: December 31, 2019 Operating lease right-of-use assets, net $ 8,105 Current portion of lease liabilities $ 337 Non-current portion of lease liabilities $ 9,965 Total operating lease liabilities $ 10,302 Weighted average remaining lease term (years) 11.8 Weighted average discount rate 11.0 % Operating lease right-of-use asset is a component of property and equipment on the consolidated balance sheet. The non-current portion of lease liabilities is a component of other long-term liabilities on the consolidated balance sheet. Supplemental cash flow information related to leases are as follows (in thousands): Year Ended December 31, 2019 Non-cash lease expense $ 264 Change in operating lease liabilities $ 186
Maturities of Lease Liabilities	Maturities of lease liabilities as of December 31, 2019 are as follows (in thousands): Year 1 $ 1,453 Year 2 1,465 Year 3 1,523 Year 4 1,531 Year 5 1,567 Thereafter 11,333 Total lease payments 18,872 Less imputed interest (8,570 ) Total $ 10,302

Quarterly Results of Operatio_2

Quarterly Results of Operations (Tables)	12 Months Ended
	Dec. 31, 2019
Quarterly Financial Information Disclosure [Abstract]
Summarized Unaudited Quarterly Financial Data	The following table summarizes unaudited quarterly financial data: Three Months Ended ($ in thousands, except for per share amounts) December 31, 2019 September 30, 2019 June 30, 2019 March 31, 2019 Consolidated Statements of Comprehensive Loss Data: Revenues $ 295 $ — $ — $ — Net loss attributable to Immunomedics, Inc. stockholders $ (99,608 ) $ (94,292 ) $ (75,953 ) $ (87,337 ) Loss per common share attributable to Immunomedics Inc. stockholders – (basic and diluted) $ (0.50 ) $ (0.49 ) $ (0.40 ) $ (0.46 ) Weighted average shares used to calculate loss per common share – (basic and diluted) 199,614 191,981 191,745 191,052 Three Months Ended ($ in thousands, except for per share amounts) December 31, 2018 September 30, 2018 June 30, 2018 March 31, 2018 Consolidated Statements of Comprehensive Loss Data: Revenues $ — $ — $ 387 $ 482 Net loss attributable to Immunomedics, Inc. stockholders $ (93,499 ) $ (64,169 ) $ (117,032 ) $ (35,546 ) Loss per common share attributable to Immunomedics Inc. stockholders – (basic and diluted) $ (0.50 ) $ (0.34 ) $ (0.68 ) $ (0.21 ) Weighted average shares used to calculate loss per common share – (basic and diluted) 190,171 186,937 171,124 166,054

Business Overview and Summary_2

Business Overview and Summary of Significant Accounting Polices - Recent Accounting Pronouncements (Details) - USD ($) $ in Thousands, shares in Millions	6 Months Ended	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2019	Jun. 30, 2018	Jun. 30, 2017	Jan. 01, 2019
Lessee, Lease, Description [Line Items]
Provisional expense from revaluation in deferred tax asset due to TCJA	$ 59,500
Antidilutive securities excluded from computation of earnings per share	6.7	8.2	10	66.1
Operating lease, liability		$ 10,302
Right-of-use asset		8,105
Other liabilities, noncurrent	$ 2,119	$ 9,965
Accounting Standards Update 2016-02
Lessee, Lease, Description [Line Items]
Operating lease, liability					$ 8,400
Right-of-use asset					8,400
Other liabilities, noncurrent					$ 10,500
Leasehold Improvements | Minimum
Lessee, Lease, Description [Line Items]
Property, plant and equipment, useful life		7 years
Leasehold Improvements | Maximum
Lessee, Lease, Description [Line Items]
Property, plant and equipment, useful life		10 years
Computer Equipment
Lessee, Lease, Description [Line Items]
Property, plant and equipment, useful life		5 years
Machinery and Equipment | Minimum
Lessee, Lease, Description [Line Items]
Property, plant and equipment, useful life		5 years
Machinery and Equipment | Maximum
Lessee, Lease, Description [Line Items]
Property, plant and equipment, useful life		10 years
Furniture and Fixtures
Lessee, Lease, Description [Line Items]
Property, plant and equipment, useful life		10 years

Revenue Recognition - Additiona

Revenue Recognition - Additional Information (Details) - USD ($) $ in Thousands	Apr. 29, 2019	Apr. 05, 2019	Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Deferred revenues			$ 65,000	$ 0
Everest Medicines II Limited
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Upfront fees paid	$ 65,000
Payment upon achievement of FDA approval	60,000
Development total payments	180,000
Sales total payments	530,000
Deferred revenues	$ 65,000
Janssen Biotech Inc
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Sales total payments		$ 15,000
Revenues			$ 300
Minimum | Everest Medicines II Limited
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Royalty payments percentage	14.00%
Maximum | Everest Medicines II Limited
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Royalty payments percentage	20.00%

Revenue Recognition - Performan

Revenue Recognition - Performance Obligation (Details) - Everest Medicines II Limited - Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2019-04-30 $ in Millions	Apr. 29, 2019USD ($)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Performance obligation	$ 65
Remaining performance obligation period	15 years

Marketable Securities - Amortiz

Marketable Securities - Amortized Cost to Fair Value (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Debt Securities, Available-for-sale [Line Items]
Fair Value	$ 4,500	$ 4,900
U.S. Government Sponsored Agencies
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	4,941	4,941
Gross Unrealized Gain	0	0
Gross Unrealized (Loss)	(391)	0
Fair Value	$ 4,550	$ 4,941

Debt - Liability Related to Sal

Debt - Liability Related to Sale of Future Royalties (Details) - USD ($) $ / shares in Units, shares in Millions	Jan. 01, 2019	Jan. 07, 2018	Dec. 31, 2018	Jun. 30, 2018	Dec. 31, 2019	Jun. 30, 2018
Debt Instrument [Line Items]
Agreement purchase shares of common stock (in shares)	4.4
Period which company will accrete liability					20 years
Annual interest rate in calculating liability related to sale of future royalties					16.00%
Rpi Finance Trust | Royalty Arrangement
Debt Instrument [Line Items]
Collaborative arrangement purchase price		$ 175,000,000
Collaborative arrangement royalty rate as percent of net sales		4.15%
Collaborative arrangement maximum royalty amount		$ 2,000,000,000
Collaborative arrangement royalty rate as percentage of excess of global annual sales threshold limit		1.75%
Collaborative arrangement excess of global annual sales threshold limit		$ 6,000,000,000
Non-cash interest expenses			$ 19,288,000	$ 19,791,000	$ 39,929,000	$ 19,800,000
Private placement | Rpi Finance Trust | Royalty Arrangement
Debt Instrument [Line Items]
Share price (in USD per share)		$ 17.15
Sale of stock, consideration received on transaction		$ 75,000,000

Debt - Consideration Allocation

Debt - Consideration Allocation (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Jun. 30, 2018	Jan. 07, 2018
Deferred Revenue Arrangement [Line Items]
Common stock	$ 2,125	$ 1,905
Rpi Finance Trust | Royalty Arrangement
Deferred Revenue Arrangement [Line Items]
Liability related to sale of future royalties	$ 261,224	$ 221,295	$ 202,007	$ 182,216
Common stock				67,784
Royalty purchase agreement arrangements consideration				$ 250,000

Debt - Schedule of Liability Re

Debt - Schedule of Liability Related to Sale of Future Royalties (Details) - USD ($) $ in Thousands	6 Months Ended		12 Months Ended
	Dec. 31, 2018	Jun. 30, 2018	Dec. 31, 2019	Jun. 30, 2018
Movement in Deferred Revenue [Roll Forward]
Liability related to sale of future royalties - current	$ 0		$ 3,455
Rpi Finance Trust | Royalty Arrangement
Movement in Deferred Revenue [Roll Forward]
Fair value, liability related to sale of future royalties, beginning balance	202,007	$ 182,216	221,295
Non-cash interest expenses	19,288	19,791	39,929	$ 19,800
Fair value, liability related to sale of future royalties, ending balance	$ 221,295	$ 202,007	261,224	$ 202,007
Liability related to sale of future royalties - current			$ 3,455

Debt - Convertible Senior Notes

Debt - Convertible Senior Notes (Details) $ / shares in Units, shares in Millions	Feb. 14, 2020USD ($)$ / sharesshares	Oct. 02, 2018USD ($)shares	Sep. 21, 2017USD ($)shares	Feb. 28, 2015USD ($)$ / sharesshares	Dec. 31, 2018USD ($)	Dec. 31, 2019USD ($)$ / shares	Jun. 30, 2018USD ($)	Jun. 30, 2017USD ($)
Deferred Revenue Arrangement [Line Items]
Issuance of common shares for debt conversion					$ 13,757,000	$ 0	$ 92,307,000	$ 0
Interest on non-recourse debt					19,288,000	39,929,000	19,791,000	0
Amortization of debt issuance costs					179,000	$ 50,000	1,679,000	730,000
Four Point Seven Five Percent Convertible Senior Notes
Deferred Revenue Arrangement [Line Items]
Debt instrument, face amount				$ 100,000,000
Proceeds from debt, net of issuance costs				96,300,000
Payments of debt issuance costs				$ 3,700,000
Debt instrument, interest rate, stated percentage				4.75%
Debt instrument, interest rate, effective percentage						5.48%
Convertible preferred stock, shares issued upon conversion (in shares) | shares				19.6
Conversion ratio				195.8336
Conversion price (in USD per share) | $ / shares				$ 5.11		$ 1,000
Percentage of principal amount redeemed				100.00%
Issuance of common shares for debt conversion			$ 80,000,000
Issuance of common stock due to debt conversion (in shares) | shares			16.8
Convertible beneficial conversion feature (in shares) | shares		0.1	1.1
Induced conversion of convertible debt expense		$ 900,000	$ 13,000,000
Outstanding balance						$ 7,100,000
Interest on non-recourse debt					500,000	400,000	3,500,000	5,500,000
Amortization of debt issuance costs					200,000	$ 100,000	1,700,000	$ 700,000
Accelerated amortization of financing costs					$ 100,000		$ 1,400,000
October 2018 Exchange Agreement
Deferred Revenue Arrangement [Line Items]
Issuance of common shares for debt conversion		$ 12,900,000
Issuance of common stock due to debt conversion (in shares) | shares		2.6
Subsequent Event | Four Point Seven Five Percent Convertible Senior Notes
Deferred Revenue Arrangement [Line Items]
Conversion price (in USD per share) | $ / shares	$ 5.11
Issuance of common stock due to debt conversion (in shares) | shares	1.4
Outstanding balance	$ 7,100,000

Stock-Based Compensation - Stoc

Stock-Based Compensation - Stock Incentive Plan (Details) - USD ($) shares in Thousands, $ in Millions	6 Months Ended	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2019	Jun. 30, 2018	Jun. 30, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock compensation expense	$ 0.9	$ 11.7	$ 4	$ 4.3
Reversed stock based compensation expense	$ 3.4
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
RSUs forfeited in period (in shares)	1,500	0

Stock-Based Compensation - Narr

Stock-Based Compensation - Narrative (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	6 Months Ended	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2019	Jun. 30, 2018	Jun. 30, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Nonvested, compensation not yet recognized, stock options		$ 40,600
Nonvested, compensation not yet recognized, period		3 years
Arrangement by share-based payment award (in USD per share)	$ 12.90	$ 8.81	$ 8.76	$ 2.21
Granted (in USD per share)	$ 0	$ 9.50	$ 7.29	$ 0
Total State	$ 0	$ 0	$ 2	$ 1
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	4 years
Granted (in USD per share)	$ 22.54	$ 15.46
Fair value of shares vested	$ 1,300	$ 8,900	300	1,400
Intrinsic value of stock-options exercised	$ 13,300	$ 14,700	$ 7,800	$ 2,600
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Nonvested, compensation not yet recognized, period	1 year 2 months 4 days	4 months 24 days
Unrecognized compensation costs	$ 300	$ 300
RSUs forfeited in period (in shares)	1,500	0
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Nonvested, compensation not yet recognized, period	3 years 18 days	9 months 18 days
Granted (in USD per share)	$ 0	$ 17.18
Fair value of shares vested		$ 1,100
Unrecognized compensation costs	$ 3,000	$ 4,900

Stock-Based Compensation - Fair

Stock-Based Compensation - Fair Value Assumptions (Details) - Employee Stock Option	6 Months Ended	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2019	Jun. 30, 2018	Jun. 30, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected dividend yield	0.00%	0.00%	0.00%	0.00%
Expected option term (years)	4 years 9 months 3 days	4 years 6 months 7 days	4 years 10 months 2 days	5 years 14 days
Expected stock price volatility	69.00%	71.00%	70.00%	63.00%
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate	2.69%	1.39%	1.72%	1.16%
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate	3.06%	2.58%	2.89%	2.15%

Stock-Based Compensation - St_2

Stock-Based Compensation - Stock Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	6 Months Ended	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2016
Weighted Average Exercise Price [Roll Forward]
Granted (in USD per share)	$ 0	$ 9.50		$ 7.29	$ 0
Employee Stock Option
Share Equivalent
Options outstanding, start of year (in shares)	3,549,000	4,757,000
Granted (in shares)	2,002,000	3,614,000
Exercise of stock options (in shares)	(706,000)	(1,207,000)
Expired or forfeited (in shares)	(88,000)	(1,263,000)
Options outstanding, end of year (in shares)	4,757,000	5,901,000	4,757,000	3,549,000
Vested, end of year (in shares)	1,504,000	1,150,000	1,504,000
Weighted Average Exercise Price [Roll Forward]
Weighted average exercise price, options outstanding, start of year (in USD per share)	$ 7.58	$ 14.30
Granted (in USD per share)	22.54	15.46
Exercised (in USD per share)	3.71	3.17
Expired or forfeited (in USD per share)	15.57	17.78
Weighted average exercise price, options outstanding, end of year (in USD per share)	14.30	16.54	$ 14.30	$ 7.58
Vested, end of year (in USD per share)	$ 4.23	$ 14.72	$ 4.23
Weighted average remaining contractual term (years) [Roll Forward]
Weighted average remaining contractual term	5 years 5 months 1 day	5 years 10 months 24 days	5 years 5 months 1 day	4 years 5 months 4 days
Weighted average remaining contractual term, end of year	3 years 4 months 28 days	4 years 7 months 9 days
Intrinsic value [Roll Forward]
Options, outstanding, intrinsic value	$ 18,618	$ 30,145	$ 18,618	$ 57,123
Options, vested, outstanding, intrinsic value end of year	$ 15,098	$ 8,276	$ 15,098
Performance Shares
Share Equivalent
Options outstanding, start of year (in shares)	538,000	538,000
Granted (in shares)	0	800,000			0	0
Exercise of stock options (in shares)	0	0
Expired or forfeited (in shares)	0	(501,000)
Options outstanding, end of year (in shares)	538,000	837,000	538,000	538,000
Vested, end of year (in shares)	38,000	50,000	38,000
Weighted Average Exercise Price [Roll Forward]
Weighted average exercise price, options outstanding, start of year (in USD per share)	$ 13.09	$ 13.09
Granted (in USD per share)	0	17.18
Exercised (in USD per share)	0	0
Expired or forfeited (in USD per share)	0	13.05
Weighted average exercise price, options outstanding, end of year (in USD per share)	13.09	17.03	$ 13.09	$ 13.09
Vested, end of year (in USD per share)	$ 11.86	$ 18.74	$ 11.86
Weighted average remaining contractual term (years) [Roll Forward]
Weighted average remaining contractual term	6 years 14 days	6 years 3 months 3 days	6 years 14 days	6 years 6 months 14 days
Weighted average remaining contractual term, end of year	5 years 11 months 8 days	6 years 10 months 17 days
Intrinsic value [Roll Forward]
Options, outstanding, intrinsic value	$ 772	$ 3,456	$ 772	$ 5,688
Options, vested, outstanding, intrinsic value end of year	$ 91	$ 121	$ 91

Stock-Based Compensation - Rest

Stock-Based Compensation - Restricted Stock Unit Activity (Details) - Restricted Stock Units (RSUs) - $ / shares shares in Thousands	6 Months Ended	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2019
Share Equivalent
Non-vested, start of year (in shares)	1,535	15
Granted (in shares)	15	58
Vested/Exercised (in shares)	(35)	(15)
Forfeited (in shares)	(1,500)	0
Non-vested, end of year (in shares)	15	58
Weighted Average Grant Date Fair Value
Nonvested, weighted average grant date fair value, start of year (in USD per share)	$ 2.83	$ 14.29
Grants in period, weighted average grant date fair value (in USD per share)	14.29	12.93
Vested/exercised, weighted average grant date fair value (in USD per share)	8.46	14.29
Forfeited, weighted average grant fate fair value (in USD per share)	2.28	0
Nonvested, weighted average grant date fair value, end of year (in USD per share)	$ 14.29	$ 12.93

Estimated Fair Value of Finan_3

Estimated Fair Value of Financial Instruments - Narrative (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets	$ 555,338	$ 331,180
Money Market Funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	550,788	326,239
U.S. Government Sponsored Agencies
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable Securities	4,550	4,941
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets	555,338	331,180
Level 1 | Money Market Funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	550,788	326,239
Level 1 | U.S. Government Sponsored Agencies
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable Securities	4,550	4,941
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets	0	0
Level 2 | Money Market Funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	0	0
Level 2 | U.S. Government Sponsored Agencies
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable Securities	0	0
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets	0	0
Level 3 | Money Market Funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	0	0
Level 3 | U.S. Government Sponsored Agencies
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable Securities	$ 0	$ 0

Estimated Fair Value of Finan_4

Estimated Fair Value of Financial Instruments - Debt Instruments (Details) - Senior Notes - Level 2 - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Convertible debt, fair value	$ 7,106	$ 7,055
Estimated Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Convertible debt, fair value	$ 28,900	$ 20,100

Property and Equipment - Schedu

Property and Equipment - Schedules of Property and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Property and equipment, gross		$ 27,785
Right-of-use asset	$ 8,368
Property, plant, and equipment and finance lease right-of-use asset, before accumulated depreciation and amortization	40,687
Accumulated depreciation and amortization	7,925
Accumulated depreciation and amortization		(4,316)
Property, plant, and equipment and finance lease right-of-use asset, after accumulated depreciation and amortization	32,762
Property, plant and equipment, net	32,762	23,469
Machinery and equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	14,331	16,048
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	11,535	6,365
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, gross	1,190	291
Computer equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	2,596	1,850
Construction in progress
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 2,667	$ 3,231

Property and Equipment - Additi

Property and Equipment - Additional Information (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2019	Jun. 30, 2018	Jun. 30, 2017
Property, Plant and Equipment [Abstract]
Depreciation and amortization expense	$ 2,099	$ 3,822	$ 1,297	$ 923

Accounts Payable and Accrued _3

Accounts Payable and Accrued Expenses (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Payables and Accruals [Abstract]
Trade accounts payable	$ 37,758	$ 20,125
Accrued contract manufacturing expenses	11,663	0
Accrued employee related expenses	7,403	315
Clinical trial accruals	2,225	5,114
Executive severance liabilities	561	2,198
Miscellaneous other current liabilities	1,250	3,970
Accounts payable and accrued expenses	$ 60,860	$ 31,722

Stockholders_ Equity (Details)

Stockholders’ Equity (Details) $ / shares in Units, $ in Thousands	Dec. 09, 2019USD ($)$ / sharesshares	Mar. 29, 2019USD ($)$ / shares	Jan. 01, 2019shares	Jun. 15, 2018USD ($)$ / sharesshares	Dec. 05, 2017USD ($)shares	Jul. 31, 2017shares	May 10, 2017USD ($)$ / sharesshares	Feb. 10, 2017USD ($)$ / sharesshares	Oct. 11, 2016USD ($)$ / sharesshares	Dec. 31, 2018USD ($)$ / sharesshares	Dec. 31, 2019USD ($)$ / sharesshares	Jun. 30, 2018USD ($)shares	Jun. 30, 2017USD ($)	Jun. 29, 2017shares	Jun. 28, 2017shares	Feb. 16, 2017USD ($)
Class of Warrant or Right [Line Items]
Common and preferred shares authorized (in shares)														260,000,000	165,000,000
Common stock, shares authorized (in shares)										250,000,000	250,000,000			250,000,000	155,000,000
Preferred stock, shares authorized (in shares)											10,000,000			10,000,000	10,000,000
Preferred stock, par value (in USD per share) | $ / shares											$ 0.01
Agreement purchase shares of common stock (in shares)			4,400,000
Common stock, par value (in USD per share) | $ / shares										$ 0.01	$ 0.01
Exercise of warrants | $										$ 1,688	$ 0	$ 78,226	$ 0
Number of shares issued in transaction (in shares)	16,428,572			13,225,000
Proceeds from public offering of common stock | $										$ 0	273,031	299,467	28,578
Payments for stock issuance costs | $												17,400
Consideration received per transaction | $											$ 71,600
Retired treasury stock (in shares)										105,959
Convertible preferred stock
Class of Warrant or Right [Line Items]
Preferred stock, shares authorized (in shares)										10,000,000	10,000,000
Preferred stock, par value (in USD per share) | $ / shares										$ 0.01	$ 0.01
Preferred stock, shares issued (in shares)										0	0
Seattle Genetics, Inc., (“SGEN”)
Class of Warrant or Right [Line Items]
Exercise of warrants (in shares)					8,655,804
Aggregate purchase price of common stock | $					$ 42,400
Securities Purchase Agreement | Seattle Genetics, Inc., (“SGEN”)
Class of Warrant or Right [Line Items]
Agreement purchase shares of common stock (in shares)						3,000,000		3,000,000
Common stock, par value (in USD per share) | $ / shares								$ 4.90
Gross proceeds from sale of common stock | $								$ 14,700
Warrants term								3 years
Shares that warrants can purchase (in shares)						8,655,804		8,655,804
Fair value of warrants | $																$ 22,300
Private placement
Class of Warrant or Right [Line Items]
Net proceeds from sale of common stock | $										$ 0	$ 0	67,784	$ 14,700
Private placement | Convertible preferred stock
Class of Warrant or Right [Line Items]
Preferred stock, shares issued (in shares)							1,000,000
Issuance of convertible preferred stock (in USD per share) | $ / shares							$ 125
Proceeds from issuance of convertible preferred stock | $							$ 125,000
Convertible preferred stock, shares issued upon conversion (in shares)							23.10536
Conversion of shares (in shares)						23,105,348	23,105,348
Share price (in USD per share) | $ / shares							$ 5.41
IPO
Class of Warrant or Right [Line Items]
Common stock, par value (in USD per share) | $ / shares									$ 3
Gross proceeds from sale of common stock | $									$ 30,000
Shares that warrants can purchase (in shares)									10,000,000
Exercise of warrants (in shares)										450,000
Net proceeds from sale of common stock | $									$ 28,600
Exercise price of warrant (in USD per share) | $ / shares									$ 3.75
Increase in fair value of warrants exercised | $												$ 102,100
Warrants outstanding (in shares)										0	450,000
Exercise of warrants | $										$ 1,700
Number of shares issued in transaction (in shares)	14,285,715			11,500,000
Proceeds from public offering of common stock | $	$ 250,000
Sale of stock (in USD per share) | $ / shares	$ 17.50			$ 24
IPO | Securities Purchase Agreement
Class of Warrant or Right [Line Items]
Fair value of warrants | $									$ 7,300
Over-Allotment Option [Member]
Class of Warrant or Right [Line Items]
Number of shares issued in transaction (in shares)	2,142,857			1,725,000
Proceeds from initial public offering, gross | $	$ 287,500
Proceeds from public offering of common stock | $	$ 273,000			$ 299,500
ATM Agreement
Class of Warrant or Right [Line Items]
Common stock, par value (in USD per share) | $ / shares		$ 0.01
Sale of stock, consideration received on transaction | $		$ 150,000
Payments for stock issuance costs percentage (as percent)		3.00%
Number of shares issued in transaction (in shares)											4,432,416
Sales Agreement
Class of Warrant or Right [Line Items]
Treasury stock, acquired (in shares)											84,896
Warrant | IPO
Class of Warrant or Right [Line Items]
Warrants exercised (in shares)												9,550,000
Weighted Average
Class of Warrant or Right [Line Items]
Shares issued, price (USD per share) | $ / shares											$ 16.40

Accumulated Other Comprehensi_3

Accumulated Other Comprehensive (Loss) Income (Details) - USD ($)	6 Months Ended	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2019	Jun. 30, 2018	Jun. 30, 2017
AOCI Attributable to Parent [Roll Forward]
Beginning balance	$ 399,686,000	$ 265,849,000	$ (59,464,000)	$ (57,528,000)
Other comprehensive loss before reclassifications	2,000	(412,000)	(50,000)	(187,000)
Amounts reclassified from accumulated other comprehensive income (loss)	0	195,000	0	16,000
Other comprehensive income (loss), net of tax:	2,000	(217,000)	(50,000)	(171,000)
Ending balance	265,849,000	267,230,000	399,686,000	(59,464,000)
Currency Translation Adjustments
AOCI Attributable to Parent [Roll Forward]
Beginning balance	(339,000)	(347,000)	(234,000)	(172,000)
Other comprehensive loss before reclassifications	(8,000)	(21,000)	(105,000)	(62,000)
Amounts reclassified from accumulated other comprehensive income (loss)	0	195,000	0	0
Other comprehensive income (loss), net of tax:	(8,000)	174,000	(105,000)	(62,000)
Ending balance	(347,000)	(173,000)	(339,000)	(234,000)
Net Unrealized Gains (Losses) on Available-for-Sale Securities
AOCI Attributable to Parent [Roll Forward]
Beginning balance	(14,000)	(4,000)	(69,000)	40,000
Other comprehensive loss before reclassifications	10,000	(391,000)	55,000	(125,000)
Amounts reclassified from accumulated other comprehensive income (loss)	0	0	0	16,000
Other comprehensive income (loss), net of tax:	10,000	(391,000)	55,000	(109,000)
Ending balance	(4,000)	(395,000)	(14,000)	(69,000)
Accumulated Other Comprehensive (Loss) Income
AOCI Attributable to Parent [Roll Forward]
Beginning balance	(353,000)	(351,000)	(303,000)	(132,000)
Other comprehensive income (loss), net of tax:	2,000	(217,000)	(50,000)	(171,000)
Ending balance	$ (351,000)	$ (568,000)	$ (353,000)	$ (303,000)

Income Taxes - Expense (Benefit

Income Taxes - Expense (Benefit) from Income Taxes (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2019	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2016
Income Tax Disclosure [Abstract]
Current	$ 0	$ 0	$ 0	$ 0
Deferred	0	0	0	0
Total Federal	0	0	0	0
Current	0	0	2	1
Deferred	0	0	0	0
Total State	0	0	2	1
Current	0	0	154	19
Deferred	0	0	0	0
Total Foreign	0	0	154	19
Total income tax expense	$ 0	$ 0	$ 156	$ 20	$ (5,100)

Income Taxes - Reconciliation o

Income Taxes - Reconciliation of Statutory Tax Rates and Effective Tax Rates (Details)	6 Months Ended	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2019	Jun. 30, 2018	Jun. 30, 2017
Income Tax Disclosure [Abstract]
Statutory rate	(21.00%)	(21.00%)	(28.00%)	(34.00%)
Foreign income tax	0.00%	0.00%	0.00%	0.00%
Change in valuation allowance	34.40%	29.90%	21.10%	21.90%
State income taxes, (net of federal tax benefit)	(8.80%)	(7.50%)	(4.30%)	(4.80%)
Permanent differences, (primarily warrant-related expenses)	(4.20%)	(1.40%)	11.30%	15.30%
Other	(0.40%)	0.00%	0.00%	1.60%
Effective rate	0.00%	0.00%	0.10%	0.00%

Income Taxes - Tax Effects of T

Income Taxes - Tax Effects of Temporary Differences in Deferred Tax Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
NOL carryforwards	$ 203,928	$ 132,841
Research and development credits	28,535	23,118
Liability related to sale of future royalties	49,228	49,217
Deferred revenue	18,286	0
Disallowed interest expense	13,474	0
Other	5,807	3,088
Total	319,258	208,264
Valuation allowance	(317,828)	(206,397)
Net deferred assets	1,430	1,867
Property and equipment	(1,430)	(1,867)
Net deferred assets and liabilities	$ 0	$ 0

Income Taxes - Narrative (Detai

Income Taxes - Narrative (Details) - USD ($)	6 Months Ended	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2019	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2016
Operating Loss Carryforwards [Line Items]
Unrecognized Tax Benefits	$ 2,521,000	$ 2,521,000	$ 0
Reduction in deferred tax assets	2,521,000	0
Reduction in valuation allowance		2,500,000
Income tax expense (benefit)	0	0	(156,000)	$ (20,000)	$ 5,100,000
Operating loss carryforward resulting from sale	0	0		$ 0	66,200,000
Research and development tax credits					$ 1,500,000
Undistributed earnings of foreign subsidiaries	0	0
Provisional expense			$ 59,500,000
Domestic Tax Authority
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	516,600,000	769,100,000
State and Local Jurisdiction
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	$ 343,000,000	$ 593,600,000

Income Taxes - Change in Unreco

Income Taxes - Change in Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2019
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance at beginning of year	$ 0	$ 2,521
Gross increases related to current period tax positions	0	0
Gross increases related to prior periods tax positions	2,521	0
Gross decreases in tax positions	0	0
Expiration of the statute of limitations	0	0
Balance at end of year	$ 2,521	$ 2,521

Related Party Transactions (Det

Related Party Transactions (Details)	Nov. 19, 2019shares	Mar. 05, 2019USD ($)shares	Dec. 31, 2018USD ($)shares	Jun. 30, 2018USD ($)shares	Jan. 06, 2018USD ($)shares	Dec. 31, 2019USD ($)shares
Related Party Transaction [Line Items]
Percent of shares forfeited upon employment commencement					0.50
Percent of shares vested upon employment commencement				0.50
M Rosenberg Bio Pharma Consulting Llc
Related Party Transaction [Line Items]
Professional and contract services expense | $			$ 300,000	$ 800,000	$ 600,000
Director
Related Party Transaction [Line Items]
Monthly salary | $		$ 16,667				$ 21,372
Salary and wage | $						$ 400,000
Executive Director
Related Party Transaction [Line Items]
Granted (in shares)		79,818				22,854
Share-based payment award						7 years
Employee Stock Option
Related Party Transaction [Line Items]
Granted (in shares)			2,002,000			3,614,000
Employee Stock Option | M Rosenberg Bio Pharma Consulting Llc
Related Party Transaction [Line Items]
Granted (in shares)					45,000
Employee Stock Option | Chief Technology Officer
Related Party Transaction [Line Items]
Stock issued during period, net of forfeitures (in shares)				104,389
Employee Stock Option | Board of Directors Chairman
Related Party Transaction [Line Items]
Granted (in shares)	150,000

Collaboration Agreements (Detai

Collaboration Agreements (Details) € in Millions	12 Months Ended
	Dec. 31, 2019EUR (€)patient
Guarantor Obligations [Line Items]
Potential milestone payment	€ 33
Potential milestone payment terms (in years)	6 years
Accrued expenses	€ 0.5
CBG Forschungs GmbH
Guarantor Obligations [Line Items]
Number of patients in clinical collaboration (in patients) | patient	1,200

Commitments and Contingencies -

Commitments and Contingencies - Narrative (Details) - USD ($) $ in Thousands	Jan. 15, 2019	Apr. 04, 2018	Dec. 31, 2018	Dec. 31, 2019	Jun. 30, 2018	Jun. 30, 2017	Mar. 13, 2019
Guarantor Obligations [Line Items]
Operating lease, liability				$ 1,300
Weighted average discount rate, percent				11.00%
Weighted average remaining lease term				11 years 9 months 18 days
Lease cost			$ 700	$ 1,400	$ 1,300	$ 900
Purchase commitments due 2020				90,000
Purchase commitments due 2021				59,800
Purchase commitments due 2022				40,800
Purchase commitments due 2023				40,800
Purchase commitments due 2024				33,000
Purchase commitments due thereafter				33,000
Payment for contingent consideration liability		$ 300
Severance benefits			$ 2,198	$ 561
Chief Executive Officer
Guarantor Obligations [Line Items]
Severance benefits							$ 1,000
Severance benefits payment term (in months)				18 months
Officers' compensation				$ 500
Salary accrued				600
Restricted Units Vesting Based on Certain Market Conditions | Goldenberg Agreement
Guarantor Obligations [Line Items]
Restricted stock units granted (in shares)	1,500,000
Employment Agreement | Goldenberg Agreement
Guarantor Obligations [Line Items]
Severance costs	$ 1,000
Insurance Coverage Arbitration
Guarantor Obligations [Line Items]
Legal fees				3,400
TSRI
Guarantor Obligations [Line Items]
Number of days license cancellable after non-payment		30 days
Milestone expense				$ 500

Commitments and Contingencies_2

Commitments and Contingencies - Supplemental Consolidated Balance Sheet Information Related to Leases (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2019USD ($)
Commitments and Contingencies Disclosure [Abstract]
Operating lease right-of-use assets, net	$ 8,105
Current portion of lease liabilities	337
Non-current portion of lease liabilities	9,965
Total operating lease liabilities	$ 10,302
Weighted average remaining lease term (years)	11 years 9 months 18 days
Weighted average discount rate	11.00%
Non-cash lease expense	$ 264
Change in operating lease liabilities	$ 186

Commitments and Contingencies_3

Commitments and Contingencies - Maturities of Lease Liabilities (Details) $ in Thousands	Dec. 31, 2019USD ($)
Commitments and Contingencies Disclosure [Abstract]
Year 1	$ 1,453
Year 2	1,465
Year 3	1,523
Year 4	1,531
Year 5	1,567
Thereafter	11,333
Total lease payments	18,872
Less imputed interest	(8,570)
Total	$ 10,302

Defined Contribution Plans (Det

Defined Contribution Plans (Details) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2019	Jun. 30, 2018	Jun. 30, 2017
Retirement Benefits [Abstract]
Employer matching contribution (as percent)		100.00%
Employer matching contribution, percent of employee's pay (as percent)		5.00%
Aggregate company contributions to its benefit plans	$ 0.1	$ 1.9	$ 0.1	$ 0.1

Quarterly Results of Operatio_3

Quarterly Results of Operations (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								6 Months Ended	12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2018	Dec. 31, 2019	Jun. 30, 2018	Jun. 30, 2017
Consolidated Statements of Comprehensive Loss Data:
Revenues	$ 295	$ 0	$ 0	$ 0	$ 0	$ 0	$ 387	$ 482	$ 0	$ 295	$ 2,156	$ 3,091
Net loss attributable to Immunomedics, Inc. stockholders	$ (99,608)	$ (94,292)	$ (75,953)	$ (87,337)	$ (93,499)	$ (64,169)	$ (117,032)	$ (35,546)	$ (157,668)	$ (357,190)	$ (273,837)	$ (153,206)
Loss per common share attributable to Immunomedics, Inc. stockholders (basic and diluted) (in USD per share)	$ (0.50)	$ (0.49)	$ (0.40)	$ (0.46)	$ (0.50)	$ (0.34)	$ (0.68)	$ (0.21)	$ (0.84)	$ (1.84)	$ (1.78)	$ (1.47)
Weighted average shares used to calculate loss per common share (basic and diluted) (in shares)	199,614	191,981	191,745	191,052	190,171	186,937	171,124	166,054	188,554	193,617	153,475	104,536

Uncategorized Items - immu20191

Label	Element	Value
Restricted Cash, Current	us-gaap_RestrictedCashCurrent	$ 3,413,000
Restricted Cash, Current	us-gaap_RestrictedCashCurrent	525,000
Restricted Cash, Current	us-gaap_RestrictedCashCurrent	$ 1,313,000