Navidea Biopharmaceuticals (NAVB) 10-Q 16 May 16 2016 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2016	May. 02, 2016
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2016
Entity Registrant Name	NAVIDEA BIOPHARMACEUTICALS, INC.
Trading Symbol	NAVB
Entity Central Index Key	810,509
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2,016
Document Fiscal Period Focus	Q1
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		155,612,734

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($)	Mar. 31, 2016	Dec. 31, 2015
Current assets:
Cash	$ 5,484,083	$ 7,166,260
Accounts and other receivables	2,800,039	3,703,186
Inventory, net	898,936	652,906
Prepaid expenses and other	853,066	1,054,822
Total current assets	10,036,124	12,577,174
Property and equipment	3,860,851	3,871,035
Less accumulated depreciation and amortization	2,079,269	1,943,427
Property and equipment, net	1,781,582	1,927,608
Patents and trademarks	222,590	233,596
Less accumulated amortization	38,149	47,438
Patents and trademarks, net	184,441	186,158
Other assets	281,534	273,573
Total assets	12,283,681	14,964,513
Current liabilities:
Accounts payable	2,901,363	1,767,523
Accrued liabilities and other	3,066,745	3,038,713
Deferred revenue, current	945,190	1,044,281
Notes payable, current, net of discounts of $1,960,631 and $0, respectively	50,179,537	333,333
Total current liabilities	57,092,835	6,183,850
Deferred revenue	26,061	192,728
Notes payable, net of discounts of $0 and $2,033,506, respectively	10,672,265	60,746,002
Other liabilities	1,653,328	1,677,633
Total liabilities	$ 69,444,489	$ 68,800,213
Commitments and contingencies
Stockholders’ deficit:
Preferred stock; $.001 par value; 5,000,000 shares authorized; no shares issued or outstanding at March 31, 2016 and December 31, 2015, respectively
Common stock; $.001 par value; 200,000,000 shares authorized; 155,505,583 and 155,649,665 shares issued and outstanding at March 31, 2016 and December 31, 2015, respectively	$ 155,506	$ 155,650
Additional paid-in capital	326,447,029	326,085,743
Accumulated deficit	(384,232,659)	(380,546,651)
Total Navidea stockholders' deficit	(57,630,124)	(54,305,258)
Noncontrolling interest	469,316	469,558
Total stockholders’ deficit	(57,160,808)	(53,835,700)
Total liabilities and stockholders’ deficit	$ 12,283,681	$ 14,964,513

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($)	Mar. 31, 2016	Dec. 31, 2015
Preferred Stock, Par or Stated Value Per Share (USD per share)	$ 0.001	$ 0.001
Preferred Stock, Shares Authorized	5,000,000	5,000,000
Preferred Stock, Shares Issued	0	0
Preferred Stock, Shares Outstanding	0	0
Common Stock, Par or Stated Value Per Share (USD per share)	$ 0.001	$ 0.001
Common Stock, Shares Authorized	200,000,000	200,000,000
Common Stock, Shares, Issued	155,505,583	155,649,665
Common Stock, Shares Outstanding	155,505,583	155,649,665
Notes Payable Current [Member]
Notes payable, discounts	$ 1,960,631	$ 0
Notes Payable Non Current [Member]
Notes payable, discounts	$ 0	$ 2,033,506

Consolidated Statements of Oper

Consolidated Statements of Operations - USD ($)	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Revenue:
Lymphoseek sales revenue	$ 3,782,680	$ 1,835,422
Lymphoseek license revenue	254,050	83,333
Grant and other revenue	685,825	189,701
Total revenue	4,722,555	2,108,456
Cost of goods sold	534,929	449,057
Gross profit	4,187,626	1,659,399
Operating expenses:
Research and development	2,659,520	3,981,288
Selling, general and administrative	4,096,660	5,494,168
Total operating expenses	6,756,180	9,475,456
Loss from operations	(2,568,554)	(7,816,057)
Other income (expense):
Interest expense, net	(2,193,523)	(966,576)
Equity in loss of R-NAV, LLC	(12,239)	(262,227)
Change in fair value of financial instruments	1,125,359	1,727,103
Other, net	(37,292)	26,532
Total other income (expense), net	(1,117,695)	524,832
Net loss	(3,686,249)	(7,291,225)
Less loss attributable to noncontrolling interest	(241)	(100)
Deemed dividend on beneficial conversion feature of MT Preferred Stock		(46,000)
Net loss attributable to common stockholders	$ (3,686,008)	$ (7,337,125)
Loss per common share (basic and diluted)	$ (0.02)	$ (0.05)
Weighted average shares outstanding (basic and diluted)	155,308,094	149,794,331

Consolidated Statement of Stock

Consolidated Statement of Stockholders' Deficit - 3 months ended Mar. 31, 2016 - USD ($)	Total	Common Stock [Member]	Additional Paid-In Capital [Member]	Accumulated Deficit [Member]	Non-controlling Interest [Member]
Balance at Dec. 31, 2015	$ (53,835,700)	$ 155,650	$ 326,085,743	$ (380,546,651)	$ 469,558
Balance, shares at Dec. 31, 2015		155,649,665
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Canceled forfeited restricted stock		$ (161)	161
Canceled forfeited restricted stock, shares		(161,000)
Issued stock in payment of Board retainers	20,640	$ 17	20,623
Issued stock in payment of Board retainers, shares		16,918
Stock compensation expense	340,502		340,502
Net loss	(3,686,249)			(3,686,008)	(241)
Balance at Mar. 31, 2016	$ (57,160,808)	$ 155,506	$ 326,447,029	$ (384,232,659)	$ 469,316
Balance, shares at Mar. 31, 2016		155,505,583

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($)	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Cash flows from operating activities:
Net loss	$ (3,686,249)	$ (7,291,225)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	149,590	149,822
Loss on disposal and abandonment of assets		5,726
Change in inventory reserve		120,302
Amortization of debt discount and issuance costs	72,875	212,813
Compounded interest on long term debt	824,952
Stock compensation expense	340,502	1,106,824
Equity in loss of R-NAV, LLC	12,239	262,227
Change in fair value of financial instruments	(1,125,359)	(1,727,103)
Issued stock to 401(k) plan for employer matching contributions	0	117,099
Other	8,401	48,971
Changes in operating assets and liabilities:
Accounts receivable	903,147	(394,471)
Inventory	(246,030)	240,478
Prepaid expenses and other assets	193,795	20,241
Accounts payable	1,133,840	428,458
Accrued and other liabilities	4,418	673,969
Deferred revenue	(265,758)	1,916,667
Net cash used in operating activities	(1,679,637)	(4,109,202)
Cash flows from investing activities:
Purchases of equipment	(1,847)
Proceeds from sales of equipment		20,300
Patent and trademark costs		(5,643)
Net cash (used in) provided by investing activities	(1,847)	14,657
Cash flows from financing activities:
Proceeds from issuance of MT Preferred Stock and warrants		500,000
Proceeds from issuance of common stock		332
Proceeds from notes payable		3,000,000
Payments under capital leases	(693)	(604)
Net cash (used in) provided by financing activities	(693)	3,499,728
Net decrease in cash	(1,682,177)	(594,817)
Cash, beginning of period	7,166,260	5,479,006
Cash, end of period	$ 5,484,083	$ 4,884,189

Summary of Significant Accounti

Summary of Significant Accounting Policies	3 Months Ended
	Mar. 31, 2016
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	1. Summary of Significant Accounting Policies a. Basis of Presentation: The information presented as of March 31, 2016 and for the three-month periods ended March 31, 2016 and 2015 is unaudited, but includes all adjustments (which consist only of normal recurring adjustments) that the management of Navidea Biopharmaceuticals, Inc. (Navidea, the Company, or we) believes to be necessary for the fair presentation of results for the periods presented. Certain information and footnote disclosures normally included in financial statements prepared in accordance with accounting principles generally accepted in the United States of America have been condensed or omitted pursuant to the rules and regulations of the U.S. Securities and Exchange Commission. The balances as of March 31, 2016 and the results for the interim periods are not necessarily indicative of results to be expected for the year. The consolidated financial statements should be read in conjunction with Navidea’s audited consolidated financial statements for the year ended December 31, 2015, which were included as part of our Annual Report on Form 10-K. Our consolidated financial statements include the accounts of Navidea and our wholly owned subsidiaries, Navidea Biopharmaceuticals Limited and Cardiosonix Ltd, as well as those of our majority-owned subsidiary, Macrophage Therapeutics, Inc. (MT). All significant inter-company accounts were eliminated in consolidation. Navidea's investment in R-NAV, LLC (R-NAV) is being accounted for using the equity method of accounting and is therefore not consolidated. b. Financial Instruments and Fair Value: In accordance with current accounting standards, the fair value hierarchy prioritizes the inputs to valuation techniques used to measure fair value, giving the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurements) and the lowest priority to unobservable inputs (Level 3 measurements). The three levels of the fair value hierarchy are described below: Level 1 – Unadjusted quoted prices in active markets that are accessible at the measurement date for identical, unrestricted assets or liabilities; Level 2 – Quoted prices in markets that are not active or financial instruments for which all significant inputs are observable, either directly or indirectly; and Level 3 – Prices or valuations that require inputs that are both significant to the fair value measurement and unobservable. A financial instrument’s level within the fair value hierarchy is based on the lowest level of any input that is significant to the fair value measurement. In determining the appropriate levels, we perform a detailed analysis of the assets and liabilities whose fair value is measured on a recurring basis. At each reporting period, all assets and liabilities for which the fair value measurement is based on significant unobservable inputs or instruments which trade infrequently and therefore have little or no price transparency are classified as Level 3. See Note 3. The following methods and assumptions were used to estimate the fair value of each class of financial instruments: (1) Cash, accounts and other receivables, accounts payable, and accrued liabilities: The carrying amounts approximate fair value because of the short maturity of these instruments. (2) Notes payable: The carrying value of our debt at March 31, 2016 and December 31, 2015 primarily consists of the face amount of the notes less unamortized discounts. See Note 8. At March 31, 2016 and December 31, 2015, certain notes payable were also required to be recorded at fair value. The estimated fair value of our debt was calculated using a discounted cash flow analysis as well as a Monte Carlo simulation. These valuation methods include Level 3 inputs such as the estimated current market interest rate for similar instruments with similar creditworthiness. Unrealized gains and losses on the fair value of the debt are classified in other expenses as a change in the fair value of financial instruments in the consolidated statements of operations. At March 31, 2016, the fair value of our notes payable is approximately $63.7 million, compared to the carrying value of $60.9 million. (3) Derivative liabilities: Derivative liabilities are related to certain outstanding warrants which are recorded at fair value. Derivative liabilities totaling $63,000 as of March 31, 2016 and December 31, 2015 were included in other liabilities on the consolidated balance sheets. The assumptions used to calculate fair value as of March 31, 2016 and December 31, 2015 included volatility, a risk-free rate and expected dividends. In addition, we considered non-performance risk and determined that such risk is minimal. Unrealized gains and losses on the derivatives are classified in other expenses as a change in the fair value of financial instruments in the statements of operations. See Note 3. c. Revenue Recognition: We currently generate revenue primarily from sales of Lymphoseek ® We earn additional revenues based on a percentage of the actual net revenues achieved by Cardinal Health on sales to end customers made during each fiscal year. The amount we charge Cardinal Health related to end customer sales of Lymphoseek are subject to a retroactive annual adjustment. To the extent that we can reasonably estimate the end-customer prices received by Cardinal Health, we record sales based upon these estimates at the time of sale. If we are unable to reasonably estimate end customer sales prices related to products sold, we record revenue related to these product sales at the minimum (i.e., floor) price provided for under our distribution agreement with Cardinal Health. During the three-month periods ended March 31, 2016 and 2015, over 99% of Lymphoseek sales were made to Cardinal Health. As of March 31, 2016, approximately 98% of accounts and other receivables were due from Cardinal Health. We also earn revenues related to our licensing and distribution agreements. The terms of these agreements may include payment to us of non-refundable upfront license fees, funding or reimbursement of research and development efforts, milestone payments if specified objectives are achieved, and/or royalties on product sales. We evaluate all deliverables within an arrangement to determine whether or not they provide value on a stand-alone basis. We recognize a contingent milestone payment as revenue in its entirety upon our achievement of a substantive milestone if the consideration earned from the achievement of the milestone (i) is consistent with performance required to achieve the milestone or the increase in value to the delivered item, (ii) relates solely to past performance and (iii) is reasonable relative to all of the other deliverables and payments within the arrangement. We received a non-refundable upfront cash payment of $2.0 million from SpePharm AG upon execution of the SpePharm License Agreement in March 2015. We have determined that the license and other non-contingent deliverables do not have stand-alone value because the license could not be deemed to be fully delivered for its intended purpose unless we perform our other obligations, including specified development work. Accordingly, they do not meet the separation criteria, resulting in these deliverables being considered a single unit of account. As a result, revenue relating to the upfront cash payment was deferred and is being recognized on a straight-line basis over the estimated obligation period of two years. We generate additional revenue from grants to support various product development initiatives. We generally recognize grant revenue when expenses reimbursable under the grants have been paid and payments under the grants become contractually due. Lastly, we recognize revenues from the provision of services to R-NAV and its subsidiaries. See Note 7. d. Recent Accounting Pronouncements: In March 2016, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) No. 2016-08, Revenue from Contracts with Customers – Principal versus Agent Considerations (Reporting Revenue Gross versus Net) . ASU 2016-08 does not change the core principle of the guidance, rather it clarifies the implementation guidance on principal versus agent considerations. ASU 2016-08 clarifies the guidance in ASU No. 2014-09, Revenue from Contracts with Customers (Topic 606) , which is not yet effective. The effective date and transition requirements for ASU 2016-08 are the same as for ASU 2014-09, which was deferred by one year by ASU No. 2015-14, Revenue from Contracts with Customers – Deferral of the Effective Date . Public business entities should adopt the new revenue recognition standard for annual reporting periods beginning after December 15, 2017, including interim periods within that year. Early adoption is permitted only as of annual reporting periods beginning after December 15, 2016, including interim periods within that year. We are currently evaluating the potential impact that the adoption of ASU 2014-09 may have on our consolidated financial statements. In March 2016, the FASB issued ASU No. 2016-09, Compensation – Stock Compensation In April 2016, the FASB issued ASU No. 2016-10, Revenue from Contracts with Customers – Identifying Performance Obligations and Licensing Revenue from Contracts with Customers (Topic 606) Revenue from Contracts with Customers – Deferral of the Effective Date

Liquidity

Liquidity	3 Months Ended
	Mar. 31, 2016
Liquidity [Abstract]
Liquidity	2. Liquidity All of our material assets, except our intellectual property, have been pledged as collateral for our borrowings under the Term Loan Agreement (the CRG Loan Agreement) with Capital Royalty Partners II L.P. (CRG). In addition to the security interest in our assets, the CRG Loan Agreement carries covenants that impose significant requirements on us, including, among others, requirements that we (1) pay all principal, interest and other charges on the outstanding balance of the borrowed funds when due; (2) maintain liquidity of at least $5 million during the term of the CRG Loan Agreement; and (3) meet certain annual EBITDA or revenue targets ($22.5 million of Lymphoseek sales revenue in 2016) as defined in the CRG Loan Agreement. The events of default under the CRG Loan Agreement also include a failure of Platinum-Montaur Life Sciences LLC, an affiliate of Platinum Management (NY) LLC, Platinum Partners Value Arbitrage Fund L.P., Platinum Partners Liquid Opportunity Master Fund L.P., Platinum Liquid Opportunity Management (NY) LLC, and Montsant Partners LLC (collectively, Platinum) to perform its funding obligations under the Platinum Loan Agreement (as defined below) at any time as to which the Company had negative EBITDA for the most recent fiscal quarter, as a result either of Platinum’s repudiation of its obligations under the Platinum Loan Agreement, or the occurrence of an insolvency event with respect to Platinum. It appears likely that we will need to draw on the Platinum line of credit in order to maintain compliance with the $5 million liquidity covenant of the CRG Loan Agreement beginning in the second quarter of 2016. Our inability to meet the liquidity covenant would be an event of default under the CRG Loan Agreement. In addition, if we are unable to reach the 2016 annual Lymphoseek sales revenue target of $22.5 million, this would also be an event of default under the CRG Loan Agreement; however, potential shortfalls to this revenue covenant are curable by the Company depositing 2.5 times the amount of the shortfall in a bank account controlled by CRG. Our ability to comply with these provisions may be affected by changes in our business condition or results of our operations, or other events beyond our control. An event of default would entitle CRG to accelerate the maturity of our indebtedness, increase the interest rate to the default rate of 18% per annum, and invoke other remedies available to it under the loan agreement and the related security agreement, which could raise substantial doubt about the Company’s ability to continue as a going concern. See Notes 8 and 9. In addition, our Loan Agreement with Platinum (the Platinum Loan Agreement) carries standard non-financial covenants typical for commercial loan agreements, many of which are similar to those contained in the CRG Loan Agreement, that impose significant requirements on us. Our ability to comply with these provisions may be affected by changes in our business condition or results of our operations, or other events beyond our control. The breach of any of these covenants would result in a default under the Platinum Loan Agreement, permitting Platinum to terminate our ability to obtain additional draws under the Platinum Loan Agreement and accelerate the maturity of the debt, subject to the limitations of the Subordination Agreement with CRG. Such actions by Platinum could materially adversely affect our operations, results of operations and financial condition, including causing us to substantially curtail our product development activities. We are currently in compliance with all covenants under the Platinum Loan Agreement. See Note 8.

Fair Value

Fair Value	3 Months Ended
	Mar. 31, 2016
Fair Value Disclosures [Abstract]
Fair Value	3 . Fair Value Platinum has the right to convert all or any portion of the unpaid principal or unpaid interest accrued on all draws under the Platinum credit facility, under certain circumstances. Platinum’s debt instrument, including the embedded option to convert such debt into common stock, is recorded at fair value on the consolidated balance sheets. The estimated fair value of the Platinum notes payable is $10.7 million at March 31, 2016. MT issued warrants to purchase MT Common Stock with certain characteristics including a net settlement provision that require the warrants to be accounted for as a derivative liability at fair value on the consolidated balance sheets. The estimated fair value of the MT warrants is $63,000 at March 31, 2016, and will continue to be measured on a recurring basis. See Note 1(b)(3). The following tables set forth, by level, financial liabilities measured at fair value on a recurring basis: Liabilities Measured at Fair Value on a Recurring Basis as of March 31, 2016 Description Quoted Active Markets for Identical Liabilities (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Total Platinum notes payable conversion option $ — $ — $ 1,886,521 $ 1,886,521 Liability related to MT warrants — — 63,000 63,000 Liabilities Measured at Fair Value on a Recurring Basis as of December 31, 2015 Description Quoted Prices in Active Markets for Identical Liabilities (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Total Platinum notes payable conversion option $ — $ — $ 3,011,880 $ 3,011,880 Liability related to MT warrants — — 63,000 63,000 a. Valuation Processes-Level 3 Measurements: The Company utilizes third-party valuation services that use complex models such as Monte Carlo simulation to estimate the value of our financial liabilities. Each reporting period, the Company provides significant unobservable inputs to the third-party valuation experts based on current internal estimates and forecasts. b. Sensitivity Analysis-Level 3 Measurements: Changes in the Company’s current internal estimates and forecasts are likely to cause material changes in the fair value of certain liabilities. The significant unobservable inputs used in the fair value measurement of the liabilities include the amount and timing of future draws expected to be taken under the Platinum Loan Agreement based on current internal forecasts and management’s estimate of the likelihood of actually making those draws as opposed to obtaining other sources of financing. Significant increases (decreases) in any of the significant unobservable inputs would result in a higher (lower) fair value measurement. A change in one of the inputs would not necessarily result in a directionally similar change in the others. There were no Level 1 liabilities outstanding at any time during the three-month periods ended March 31, 2016 and 2015. There were no transfers in or out of our Level 2 liabilities during the three-month periods ended March 31, 2016 or 2015. Changes in the estimated fair value of our Level 3 liabilities relating to unrealized gains (losses) are recorded as changes in fair value of financial instruments in the consolidated statements of operations. The change in the estimated fair value of our Level 3 liabilities during the three-month periods ended March 31, 2016 and 2015 was a decrease of $1.1 million and $1.7 million, respectively.

Stock-Based Compensation

Stock-Based Compensation	3 Months Ended
	Mar. 31, 2016
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock-Based Compensation	4. Stock-Based Compensation For the three-month periods ended March 31, 2016 and 2015, our total stock-based compensation expense, which includes reversals of expense for certain forfeited or cancelled awards, was approximately $341,000 and $1.1 million, respectively. We have not recorded any income tax benefit related to stock-based compensation in either of the three-month periods ended March 31, 2016 and 2015. A summary of the status of our stock options as of March 31, 2016, and changes during the three-month period then ended, is presented below: Three Months Ended March 31, 2016 Number of Options Weighted Average Exercise Price Weighted Average Remaining Contractual Life Aggregate Intrinsic Value Outstanding at beginning of period 5,437,064 $ 1.96 Granted 366,457 0.96 Exercised — — Canceled and Forfeited (112,000 ) 1.86 Expired (299,000 ) 2.42 Outstanding at end of period 5,392,521 $ 1.87 7.5 years $ 104,600 Exercisable at end of period 3,337,968 $ 2.03 6.8 years $ 101,276 A summary of the status of our unvested restricted stock as of March 31, 2016, and changes during the three-month period then ended, is presented below: Three Months Ended March 31, 2016 Number of Shares Weighted Average Grant-Date Fair Value Unvested at beginning of period 361,000 $ 1.69 Granted — — Vested (66,000 ) 1.65 Forfeited (161,000 ) 1.75 Unvested at end of period 134,000 $ 1.63 During the three-month period ended March 31, 2016, 66,000 shares of restricted stock held by non-employee directors with an aggregate fair value of $63,360 vested as scheduled according to the terms of the restricted stock agreements. Also during the three-month period ended March 31, 2016, 161,000 shares of unvested restricted stock were forfeited upon termination of certain directors and an officer. As of March 31, 2016, there was approximately $815,000 of total unrecognized compensation expense related to unvested stock-based awards, which we expect to recognize over the remaining weighted average vesting term of 1.7 years.

Earnings (Loss) Per Share

Earnings (Loss) Per Share	3 Months Ended
	Mar. 31, 2016
Earnings Per Share [Abstract]
Earnings (Loss) Per Share	5. Earnings (Loss) Per Share Basic earnings (loss) per share is calculated by dividing net income (loss) attributable to common stockholders by the weighted-average number of common shares and, except for periods with a loss from operations, participating securities outstanding during the period. Diluted earnings (loss) per share reflects additional common shares that would have been outstanding if dilutive potential common shares had been issued. Potential common shares that may be issued by the Company include convertible debt, convertible preferred stock, options and warrants. Diluted earnings (loss) per common share for the three-month periods ended March 31, 2016 and 2015 excludes the effects of 15.1 million and 20.1 million common share equivalents, respectively, since such inclusion would be anti-dilutive. The excluded shares consist of common shares issuable upon exercise of outstanding stock options and warrants, and upon the conversion of convertible debt and convertible preferred stock. The Company’s unvested stock awards contain nonforfeitable rights to dividends or dividend equivalents, whether paid or unpaid (referred to as “participating securities”). Therefore, the unvested stock awards are required to be included in the number of shares outstanding for both basic and diluted earnings per share calculations. However, due to our loss from continuing operations, 134,000 and 671,500 shares of unvested restricted stock for the three-month periods ended March 31, 2016 and 2015, respectively, were excluded in determining basic and diluted loss per share because such inclusion would be anti-dilutive.

Inventory

Inventory	3 Months Ended
	Mar. 31, 2016
Inventory Disclosure [Abstract]
Inventory	6. Inventory All components of inventory are valued at the lower of cost (first-in, first-out) or market. We adjust inventory to market value when the net realizable value is lower than the carrying cost of the inventory. Market value is determined based on estimated sales activity and margins. We estimate a reserve for obsolete inventory based on management’s judgment of probable future commercial use, which is based on an analysis of current inventory levels, estimated future sales and production rates, and estimated shelf lives. The components of inventory as of March 31, 2016 and December 31, 2015 are as follows: March 31, 2016 December 31, 2015 (unaudited) Materials $ 30,000 $ 330,000 Work-in-process 108,518 392,457 Finished goods 938,324 275,168 Reserves (177,906 ) (344,719 ) Total $ 898,936 $ 652,906 During the three-month period ended March 31, 2015, we wrote off $120,000 of materials related to production issues. During the three-month period ended March 31, 2015, the Company used $37,000 of Lymphoseek inventory for clinical study and product development purposes.

Investment in R-NAV, LLC

Investment in R-NAV, LLC	3 Months Ended
	Mar. 31, 2016
Equity Method Investments And Joint Ventures [Abstract]
Investment in R-NAV, LLC	7. Investment in R-NAV, LLC Navidea’s investment in R-NAV, LLC (R-NAV) of approximately 27% is being accounted for using the equity method of accounting. Navidea’s equity in the loss of R-NAV was $12,239 and $262,227, respectively, for the three-month periods ended March 31, 2016 and 2015. Navidea’s equity in the loss of R-NAV has exceeded our initial investment in R-NAV. As such, the carrying value of the Company’s investment in R-NAV was $0 as of March 31, 2016 and December 31, 2015. The Company’s obligation to provide $500,000 of in-kind services to R-NAV is being recognized as those services are provided. The Company provided $12,000 and $21,000, respectively, of in-kind services during the three-month periods ended March 31, 2016 and 2015. As of March 31, 2016, the Company has $385,000 of in-kind services remaining to provide under this obligation. Navidea provides additional services to R-NAV in support of its development activities. Such services are immaterial to Navidea’s overall operations.

Notes Payable

Notes Payable	3 Months Ended
	Mar. 31, 2016
Debt Disclosure [Abstract]
Notes Payable	8. Notes Payable Platinum In July 2012, we entered into an agreement with Platinum to provide us with a credit facility of up to $50 million. Following the approval of Lymphoseek, Platinum was committed under the terms of the agreement to extend up to $35 million in debt financing to the Company. During the three-month period ended March 31, 2016, $306,000 of interest was compounded and added to the balance of the Platinum Note. As of March 31, 2016, the outstanding principal balance of the Platinum Note was approximately $8.8 million, with $27.3 million currently available under the credit facility. An additional $15 million is potentially available under the credit facility on terms to be negotiated. The Platinum Note is reflected on the consolidated balance sheets at its estimated fair value, which includes the estimated fair value of the embedded conversion option of $1.9 million. Changes in the estimated fair value of the Platinum Note were decreases of $1.1 million and $1.7 million, respectively, and were recorded as non-cash changes in fair value of the conversion option during the three-month periods ended March 31, 2016 and 2015. The estimated fair value of the Platinum Note was $10.7 million as of March 31, 2016. Capital Royalty Partners II, L.P. In May 2015, Navidea and its subsidiary Macrophage Therapeutics, Inc., as guarantor, executed a Term Loan Agreement (the CRG Loan Agreement) with Capital Royalty Partners II L.P. (CRG) in its capacity as a lender and as control agent for other affiliated lenders party to the CRG Loan Agreement (collectively, the Lenders) in which the Lenders agreed to make a term loan to the Company in the aggregate principal amount of $50 million (the CRG Term Loan), with an additional $10 million in loans to be made available upon the satisfaction of certain conditions stated in the CRG Loan Agreement. During the three-month period ended March 31, 2016, $519,000 of interest was compounded and added to the balance of the CRG Term Loan. As of March 31, 2016, the outstanding principal balance of the CRG Term Loan was $51.8 million. In connection with the CRG Loan Agreement, the Company recorded a debt discount related to lender fees and other costs directly attributable to the CRG Loan Agreement totaling $2.2 million, including a $1.0 million facility fee which is payable at the end of the term or when the loan is repaid in full. A long-term liability has been recorded for the $1.0 million facility fee. The debt discount is being amortized as non-cash interest expense using the effective interest method over the term of the CRG Loan Agreement. As of March 31, 2016, the balance of the debt discount was $2.0 million. The CRG Term Loan is collateralized by a security interest in substantially all of the Company's assets. In addition, the CRG Loan Agreement requires that the Company adhere to certain affirmative and negative covenants, including financial reporting requirements and a prohibition against the incurrence of indebtedness, or creation of additional liens, other than as specifically permitted by the terms of the CRG Loan Agreement. The Lenders may accelerate the payment terms of the CRG Loan Agreement upon the occurrence of certain events of default set forth therein, which include the failure of the Company to make timely payments of amounts due under the CRG Loan Agreement, the failure of the Company to adhere to the covenants set forth in the CRG Loan Agreement, and the insolvency of the Company. The covenants of the CRG Loan Agreement include a covenant that the Company shall have EBITDA of no less than $5 million in each calendar year during the term or revenues from sales of Lymphoseek in each calendar year during the term of at least $22.5 million in 2016, with the target minimum revenue increasing in each year thereafter until reaching $45 million in 2020. However, if the Company were to fail to meet the applicable minimum EBITDA or revenue target in any calendar year, the CRG Loan Agreement provides the Company a cure right if it raises 2.5 times the EBITDA or revenue shortfall in equity or subordinated debt and deposits such funds in a separate blocked account. Additionally, the Company must maintain liquidity, defined as the balance of unencumbered cash and permitted cash equivalent investments, of at least $5 million during the term of the CRG Term Loan. The events of default under the CRG Loan Agreement also include a failure of Platinum to perform its funding obligations under the Platinum Loan Agreement at any time as to which the Company had negative EBITDA for the most recent fiscal quarter, as a result either of Platinum’s repudiation of its obligations under the Platinum Loan Agreement, or the occurrence of an insolvency event with respect to Platinum. On April 7, 2016, we received a notice (the First Notice) from CRG, pursuant to the CRG Loan Agreement. The First Notice claims that Events of Default have occurred under Sections 11.01(m) (alleging that a Change of Control has occurred), 11.01(e) (alleging that the Company’s agreement with Platinum reported in the Company’s Current Report on Form 8-K filed on March 18, 2016 constituted an amendment, modification, waiver or supplement to the Loan Agreement, dated July 25, 2012, between the Company and Platinum that required the written consent of CRG and that a subsidiary of the Company opened a bank account without notifying CRG), and 11.01(d) (alleging that the failure by the Company to notify CRG of a Default itself constitutes an Event of Default) of the Loan Agreement. The Company also learned that CRG filed an Original Petition (the Petition) in the District Court for Harris County, Texas alleging the same Events of Default as set forth in the Notice and seeking an undetermined amount of damages and a declaratory judgment that the Company is in default under the Loan Agreement and that CRG, as a result, is entitled to the remedies set forth in Section 11.02 of the Loan Agreement. In the First Notice, CRG indicated that it elected not to require the amounts due under the CRG Loan Agreement to be immediately due and payable, but claimed that the Obligations under the CRG Loan Agreement shall accrue interest at the default rate of 18% per annum until paid in full. We did not achieve the 2015 annual Lymphoseek sales revenue target of $11 million as initially established under the CRG Loan Agreement, but in December 2015 CRG agreed to a reduction of that target to $10 million (Amendment 1) and we were able to meet that reduced target with Lymphoseek sales revenue of $10.3 million, thereby complying with the covenant. On April 22, 2016 we received an additional notice (the Second Notice) from CRG, pursuant to the CRG Loan Agreement. The Second Notice claims that Amendment 1 is invalid due to the existence of Events of Default at the time of its execution in December 2015 which were not disclosed to CRG at that time. Consequently, CRG claimed that the Company failed to satisfy Section 3(b) of Amendment 1 in order for Amendment 1 to become effective and breached Section 4(a)(iii) of Amendment 1, and as such, Amendment 1 is of no effect and the Company is bound by the 2015 annual Lymphoseek sales revenue target of $11 million as originally set forth in the CRG Loan Agreement. Since the Company’ 2015 Lymphoseek sales revenue was $10.3 million, the Second Notice claims that an additional Event of Default has occurred under Section 11.01(d) of the CRG Loan Agreement. On April 28, 2016, the Company received a further notice (the Third Notice) from CRG informing the Company that CRG commenced exercising its remedies, including with respect to cash collateral. In that regard, CRG informed the Company that it had delivered notices to exercise control of the Company’s accounts pursuant to the blocked account control and pledge collateral account control agreements with CRG. On May 2, 2016, the Company successfully sought a temporary restraining order in Harris County Court, Texas, in which the court enjoined CRG from causing any further “freeze” of the Company’s accounts and required CRG to restore the accounts to the position they were in prior to CRG’s April 28, 2016 acts, pending a more complete review of the Company’s and CRG’s positions in the lawsuit in a hearing scheduled for May 19, 2016. The Company is maintaining its position that the alleged claims do not constitute Events of Default under the CRG Loan Agreement and intends to vigorously defend against these claims. The Company continues to evaluate its options, including the possible assertion of counterclaims. However, if the Company does not prevail in these legal proceedings, CRG may invoke any and all remedies available to it under the loan agreement and the related security agreement, including acceleration of the maturity of our indebtedness, which could materially adversely affect our ability to continue as a going concern. Based on CRG’s claims that the Company is in default under the terms of the CRG Loan Agreement, and in accordance with current accounting guidance, the Company has classified the net balance of the CRG Term Loan as a current liability as of March 31, 2016. R-NAV, LLC As of March 31, 2016, the outstanding principal balance of the note payable to R-NAV was $333,333 which is due in July 2016. Summary During the three-month periods ended March 31, 2016 and 2015, we recorded interest expense of $2.2 million and $967,000, respectively, related to our notes payable. Of these amounts, $73,000 and $213,000, respectively, related to amortization of the debt discounts related to our notes payable. An additional $825,000 of total interest expense was compounded and added to the balance of our notes payable during the three-month period ended March 31, 2016.

Commitments and Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2016
Commitments And Contingencies Disclosure [Abstract]
Commitments and Contingencies	9. Commitments and Contingencies Sinotau Litigation On August 31, 2015, Sinotau Pharmaceutical Group (Sinotau) filed a suit for damages, specific performance and injunctive relief against the Company in the United States District Court for the District of Massachusetts alleging breach of a letter of intent for licensing to Sinotau of the Company’s NAV4694 product candidate and technology. The Company believes the suit is without merit and has filed a motion to dismiss the action. At this time, it is not possible to determine with any degree of certainty the ultimate outcome of this legal proceeding, including making a determination of liability. CRG Litigation On April 7, 2016, we received a notice (the First Notice) from CRG, pursuant to the CRG Loan Agreement. The First Notice claims that Events of Default have occurred under Sections 11.01(m) (alleging that a Change of Control has occurred), 11.01(e) (alleging that the Company’s agreement with Platinum reported in the Company’s Current Report on Form 8-K filed on March 18, 2016 constituted an amendment, modification, waiver or supplement to the Loan Agreement, dated July 25, 2012, between the Company and Platinum that required the written consent of CRG and that a subsidiary of the Company opened a bank account without notifying CRG), and 11.01(d) (alleging that the failure by the Company to notify CRG of a Default itself constitutes an Event of Default) of the Loan Agreement. The Company also learned that CRG filed an Original Petition (the Petition) in the District Court for Harris County, Texas alleging the same Events of Default as set forth in the Notice and seeking an undetermined amount of damages and a declaratory judgment that the Company is in default under the Loan Agreement and that CRG, as a result, is entitled to the remedies set forth in Section 11.02 of the Loan Agreement. In the First Notice, CRG indicated that it elected not to require the amounts due under the CRG Loan Agreement to be immediately due and payable, but claimed that the Obligations under the CRG Loan Agreement shall accrue interest at the default rate of 18% until paid in full. We did not achieve the 2015 annual Lymphoseek sales revenue target of $11 million as initially established under the CRG Loan Agreement, but in December 2015 CRG agreed to a reduction of that target to $10 million (Amendment 1) and we were able to meet that reduced target with Lymphoseek sales revenue of $10.3 million, thereby complying with the covenant. On April 22, 2016 we received an additional notice (the Second Notice) from CRG, pursuant to the CRG Loan Agreement. The Second Notice claims that Amendment 1 is invalid due to the existence of Events of Default at the time of its execution in December 2015 which were not disclosed to CRG at that time. Consequently, CRG claimed that the Company failed to satisfy Section 3(b) of Amendment 1 in order for Amendment 1 to become effective and breached Section 4(a)(iii) of Amendment 1, and as such, Amendment 1 is of no effect and the Company is bound by the 2015 annual Lymphoseek sales revenue target of $11 million as originally set forth in the CRG Loan Agreement. Since the Company’s 2015 Lymphoseek sales revenue was $10.3 million, the Second Notice claims that an additional Event of Default has occurred under Section 11.01(d) of the CRG Loan Agreement. On April 28, 2016, the Company received a further notice (the Third Notice) from CRG informing the Company that CRG commenced exercising its remedies, including with respect to cash collateral. In that regard, CRG informed the Company that it had delivered notices to exercise control of the Company’s accounts pursuant to the blocked account control and pledge collateral account control agreements with CRG. On May 2, 2016, the Company successfully sought a temporary restraining order in Harris County Court, Texas, in which the court enjoined CRG from causing any further “freeze” of the Company’s accounts and required CRG to restore the accounts to the position they were in prior to CRG’s April 28, 2016 acts, pending a more complete review of the Company’s and CRG’s positions in the lawsuit in a hearing scheduled for May 19, 2016. The Company is maintaining its position that the alleged claims do not constitute Events of Default under the Loan Agreement and intends to vigorously defend against these claims. The Company continues to evaluate its options, including the possible assertion of counterclaims. However, if the Company does not prevail in these legal proceedings, CRG may invoke any and all remedies available to it under the loan agreement and the related security agreement, including acceleration of the maturity of our indebtedness, which could materially adversely affect our ability to continue as a going concern. See Notes 2 and 8.

Equity Instruments

Equity Instruments	3 Months Ended
	Mar. 31, 2016
Equity [Abstract]
Equity Instruments	10 . Equity Instruments During the three-month period ended March 31, 2016, we issued 16,918 shares of our common stock valued at $21,000 to a member of our Board of Directors as payment in lieu of cash for his fourth quarter 2015 compensation.

Stock Warrants

Stock Warrants	3 Months Ended
	Mar. 31, 2016
Warrants And Rights Note Disclosure [Abstract]
Stock Warrants	11. Stock Warrants At March 31, 2016, there are 11.7 million warrants outstanding to purchase Navidea's common stock. The warrants are exercisable at prices ranging from $0.01 to $3.04 per share with a weighted average exercise price of $0.38 per share. The warrants have remaining outstanding terms ranging from 1 to 19 years. In addition, at March 31, 2016, there are 300 warrants outstanding to purchase MT Common Stock. The warrants are exercisable at $2,000 per share.

Income Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2016
Income Tax Disclosure [Abstract]
Income Taxes	12. Income Taxes Income taxes are accounted for under the asset and liability method. Deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases, and operating loss and tax credit carryforwards. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period that includes the enactment date. Due to the uncertainty surrounding the realization of the deferred tax assets in future tax returns, all of the deferred tax assets have been fully offset by a valuation allowance at March 31, 2016 and December 31, 2015. Current accounting standards include guidance on the accounting for uncertainty in income taxes recognized in the financial statements. Such standards also prescribe a recognition threshold and measurement model for the financial statement recognition of a tax position taken, or expected to be taken, and provides guidance on derecognition, classification, interest and penalties, accounting in interim periods, disclosure and transition. The Company believes that the ultimate deductibility of all tax positions is highly certain, although there is uncertainty about the timing of such deductibility. As a result, no liability for uncertain tax positions was recorded as of March 31, 2016 or December 31, 2015 and we do not expect any significant changes in the next twelve months. Should we need to accrue interest or penalties on uncertain tax positions, we would recognize the interest as interest expense and the penalties as a selling, general and administrative expense. As of March 31, 2016, tax years 2012-2015 remained subject to examination by federal and state tax authorities.

Segments

Segments	3 Months Ended
	Mar. 31, 2016
Segment Reporting [Abstract]
Segments	13. Segments We report information about our operating segments using the “management approach” in accordance with current accounting standards. This information is based on the way management organizes and reports the segments within the enterprise for making operating decisions and assessing performance. Our reportable segments are identified based on differences in products, services and markets served. There were no inter-segment sales. Prior to 2015, our products and development programs were all related to diagnostic substances. Our majority-owned subsidiary, Macrophage Therapeutics, Inc., was formed and received initial funding during the first quarter of 2015, which resulted in a re-evaluation of the Company's segment determination. We now manage our business based on two primary types of drug products: (i) diagnostic substances, including Lymphoseek and other diagnostic applications of our Manocept platform, our R-NAV subsidiary, NAV4694 and NAV5001 (license terminated in April 2015), and (ii) therapeutic development programs, including therapeutic applications of our Manocept platform and all development programs undertaken by Macrophage Therapeutics, Inc. The information in the following tables is derived directly from each reportable segment’s financial reporting. Three Months Ended March 31, 2016 Diagnostics Therapeutics Corporate Total Lymphoseek sales revenue: United States (1) $ 3,771,420 $ — $ — $ 3,771,420 International 11,260 — — 11,260 Lymphoseek license revenue 254,050 — — 254,050 Grant and other revenue 685,825 — — 685,825 Total revenue 4,722,555 — — 4,722,555 Cost of goods sold, excluding depreciation and amortization 494,639 — — 494,639 Research and development expenses, excluding depreciation and amortization 2,417,720 241,800 — 2,659,520 Selling, general and administrative expenses, excluding depreciation and amortization (2) 1,012,106 (598 ) 2,975,850 3,987,358 Depreciation and amortization (3) 40,290 — 109,302 149,592 Loss from operations (4) 757,800 (241,202 ) (3,085,152 ) (2,568,554 ) Other income (expense), excluding equity in the loss of R-NAV, LLC (5) — — (1,105,456 ) (1,105,456 ) Equity in the loss of R-NAV, LLC — — (12,239 ) (12,239 ) Net loss 757,800 (241,202 ) (4,202,847 ) (3,686,249 ) Total assets, net of depreciation and amortization: United States 4,109,640 16,515 7,774,939 11,901,094 International 380,982 — 1,605 382,587 Capital expenditures — — 1,847 1,847 Three Months Ended March 31, 2015 Diagnostics Therapeutics Corporate Total Lymphoseek sales revenue: United States (1) $ 1,831,022 $ — $ — $ 1,831,022 International 4,400 — — 4,400 Lymphoseek license revenue 83,333 — — 83,333 Grant and other revenue 189,701 — — 189,701 Total revenue 2,108,456 — — 2,108,456 Cost of goods sold, excluding depreciation and amortization 420,551 — — 420,551 Research and development expenses, excluding depreciation and amortization 3,890,724 86,014 — 3,976,738 Selling, general and administrative expenses, excluding depreciation and amortization (2) 2,042,175 14,366 3,320,861 5,377,402 Depreciation and amortization (3) 33,056 — 116,766 149,822 Loss from operations (4) (4,278,050 ) (100,380 ) (3,437,627 ) (7,816,057 ) Other income (expense), excluding equity in the loss of R-NAV, LLC (5) — — 787,059 787,059 Equity in the loss of R-NAV, LLC — — (262,227 ) (262,227 ) Net loss (4,278,050 ) (100,380 ) (2,912,795 ) (7,291,225 ) Total assets, net of depreciation and amortization: United States 3,333,851 7,409 7,077,673 10,418,933 International 496,311 — 2,665 498,976 Capital expenditures — — — — (1) All sales to Cardinal Health are made in the United States; Cardinal distributes the product throughout the U.S. through its network of nuclear pharmacies. (2) General and administrative expenses, excluding depreciation and amortization, represent costs that relate to the general administration of the Company and as such are not currently allocated to our individual reportable segments. Marketing and selling expenses are allocated to our individual reportable segments. (3) (4) Loss from operations does not reflect the allocation of certain selling, general and administrative expenses, excluding depreciation and amortization, to our individual reportable segments. (5) Amounts consist primarily of interest income, interest expense, changes in fair value of financial instruments, and losses on debt extinguishment, which are not currently allocated to our individual reportable segments.

Supplemental Disclosure for Sta

Supplemental Disclosure for Statements of Cash Flows	3 Months Ended
	Mar. 31, 2016
Supplemental Cash Flow Elements [Abstract]
Supplemental Disclosure for Statements of Cash Flows	14. Supplemental Disclosure for Statements of Cash Flows During the three-month periods ended March 31, 2016 and 2015, we paid interest aggregating $1.3 million and $701,000, respectively. During the three-month period ended March 31, 2015, we issued 68,157 shares of our common stock as a matching contribution to our 401(k) Plan which were valued at $117,000.

Subsequent Event

Subsequent Event	3 Months Ended
	Mar. 31, 2016
Subsequent Events [Abstract]
Subsequent Event	15. Subsequent Events a. CRG Notice of Default: On April 7, 2016, we received a notice (the First Notice) from CRG, pursuant to the CRG Loan Agreement. The First Notice claims that Events of Default have occurred under Sections 11.01(m) (alleging that a Change of Control has occurred), 11.01(e) (alleging that the Company’s agreement with Platinum reported in the Company’s Current Report on Form 8-K filed on March 18, 2016 constituted an amendment, modification, waiver or supplement to the Loan Agreement, dated July 25, 2012, between the Company and Platinum that required the written consent of CRG and that a subsidiary of the Company opened a bank account without notifying CRG), and 11.01(d) (alleging that the failure by the Company to notify CRG of a Default itself constitutes an Event of Default) of the Loan Agreement. The Company also learned that CRG filed an Original Petition (the Petition) in the District Court for Harris County, Texas alleging the same Events of Default as set forth in the Notice and seeking an undetermined amount of damages and a declaratory judgment that the Company is in default under the Loan Agreement and that CRG, as a result, is entitled to the remedies set forth in Section 11.02 of the Loan Agreement. In the First Notice, CRG indicated that it elected not to require the amounts due under the CRG Loan Agreement to be immediately due and payable, but claimed that the Obligations under the CRG Loan Agreement shall accrue interest at a rate equal to the Default Rate of 18% per annum until paid in full. We did not achieve the 2015 annual Lymphoseek sales revenue target of $11 million as initially established under the CRG Loan Agreement, but in December 2015 CRG agreed to a reduction of that target to $10 million (Amendment 1) and we were able to meet that reduced target with Lymphoseek sales revenue of $10.3 million, thereby complying with the covenant. On April 22, 2016 we received an additional notice (the Second Notice) from CRG, pursuant to the CRG Loan Agreement. The Second Notice claims that Amendment 1 is invalid due to the existence of Events of Default at the time of its execution in December 2015 which were not disclosed to CRG at that time. Consequently, CRG claimed that the Company failed to satisfy Section 3(b) of Amendment 1 in order for Amendment 1 to become effective and breached Section 4(a)(iii) of Amendment 1, and as such, Amendment 1 is of no effect and the Company is bound by the 2015 annual Lymphoseek sales revenue target of $11 million as originally set forth in the CRG Loan Agreement. Since the Company’ 2015 Lymphoseek sales revenue was $10.3 million, the Second Notice claims that an additional Event of Default has occurred under Section 11.01(d) of the CRG Loan Agreement. On April 28, 2016, the Company received a further notice (the Third Notice) from CRG informing the Company that CRG commenced exercising its remedies, including with respect to cash collateral. In that regard, CRG informed the Company that it had delivered notices to exercise control of the Company’s accounts pursuant to the blocked account control and pledge collateral account control agreements with CRG. On May 2, 2016, the Company successfully sought a temporary restraining order in Harris County Court, Texas, in which the court enjoined CRG from causing any further “freeze” of the Company’s accounts and required CRG to restore the accounts to the position they were in prior to CRG’s April 28, 2016 acts, pending a more complete review of the Company’s and CRG’s positions in the lawsuit in a hearing scheduled for May 19, 2016. The Company is maintaining its position that the alleged claims do not constitute Events of Default under the Loan Agreement and intends to vigorously defend against these claims. The Company continues to evaluate its options, including the possible assertion of counterclaims. However, if the Company does not prevail in these legal proceedings, CRG may invoke any and all remedies available to it under the loan agreement and the related security agreement, including acceleration of the maturity of our indebtedness, which could materially adversely affect our ability to continue as a going concern. Based on CRG’s claims that the Company is in default under the terms of the CRG Loan Agreement, and in accordance with current accounting guidance, the Company has classified the net balance of the CRG Term Loan as a current liability as of March 31, 2016. b. Termination of CEO: On May 12, 2016 the Company received a demand for arbitration through the American Arbitration Association, Columbus, Ohio, from Ricardo J. Gonzalez, the Company’s then Chief Executive Officer, claiming that he was terminated without cause and, alternatively, that he resigned in accordance with Section 4G of his Employment Agreement pursuant to a notice received by the Company on May 9, 2016. On May 13, 2016, the Company notified Mr. Gonzalez that his failure to undertake responsibilities assigned to him by the Board of Directors and otherwise work after being ordered to do so on multiple occasions constituted an effective resignation, and the Company accepted that resignation. The Company rejected the resignation of Mr. Gonzalez pursuant to Section 4G of his Employment Agreement. Also, the Company notified Mr. Gonzalez that, alternatively, his failure to return to work after the expiration of the cure period provided in his Employment Agreement constituted cause for his termination under his Employment Agreement. Mr. Gonzalez is seeking severance and other amounts claimed to be owed to him under his employment agreement. The Company believes that it has meritorious defenses to the claims by Mr. Gonzalez and intends to vigorously defend its position.

Summary of Significant Accoun22

Summary of Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2016
Accounting Policies [Abstract]
Basis of Presentation	a. Basis of Presentation: The information presented as of March 31, 2016 and for the three-month periods ended March 31, 2016 and 2015 is unaudited, but includes all adjustments (which consist only of normal recurring adjustments) that the management of Navidea Biopharmaceuticals, Inc. (Navidea, the Company, or we) believes to be necessary for the fair presentation of results for the periods presented. Certain information and footnote disclosures normally included in financial statements prepared in accordance with accounting principles generally accepted in the United States of America have been condensed or omitted pursuant to the rules and regulations of the U.S. Securities and Exchange Commission. The balances as of March 31, 2016 and the results for the interim periods are not necessarily indicative of results to be expected for the year. The consolidated financial statements should be read in conjunction with Navidea’s audited consolidated financial statements for the year ended December 31, 2015, which were included as part of our Annual Report on Form 10-K. Our consolidated financial statements include the accounts of Navidea and our wholly owned subsidiaries, Navidea Biopharmaceuticals Limited and Cardiosonix Ltd, as well as those of our majority-owned subsidiary, Macrophage Therapeutics, Inc. (MT). All significant inter-company accounts were eliminated in consolidation. Navidea's investment in R-NAV, LLC (R-NAV) is being accounted for using the equity method of accounting and is therefore not consolidated.
Financial Instruments and Fair Value	b. Financial Instruments and Fair Value: In accordance with current accounting standards, the fair value hierarchy prioritizes the inputs to valuation techniques used to measure fair value, giving the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurements) and the lowest priority to unobservable inputs (Level 3 measurements). The three levels of the fair value hierarchy are described below: Level 1 – Unadjusted quoted prices in active markets that are accessible at the measurement date for identical, unrestricted assets or liabilities; Level 2 – Quoted prices in markets that are not active or financial instruments for which all significant inputs are observable, either directly or indirectly; and Level 3 – Prices or valuations that require inputs that are both significant to the fair value measurement and unobservable. A financial instrument’s level within the fair value hierarchy is based on the lowest level of any input that is significant to the fair value measurement. In determining the appropriate levels, we perform a detailed analysis of the assets and liabilities whose fair value is measured on a recurring basis. At each reporting period, all assets and liabilities for which the fair value measurement is based on significant unobservable inputs or instruments which trade infrequently and therefore have little or no price transparency are classified as Level 3. See Note 3. The following methods and assumptions were used to estimate the fair value of each class of financial instruments: (1) Cash, accounts and other receivables, accounts payable, and accrued liabilities: The carrying amounts approximate fair value because of the short maturity of these instruments. (2) Notes payable: The carrying value of our debt at March 31, 2016 and December 31, 2015 primarily consists of the face amount of the notes less unamortized discounts. See Note 8. At March 31, 2016 and December 31, 2015, certain notes payable were also required to be recorded at fair value. The estimated fair value of our debt was calculated using a discounted cash flow analysis as well as a Monte Carlo simulation. These valuation methods include Level 3 inputs such as the estimated current market interest rate for similar instruments with similar creditworthiness. Unrealized gains and losses on the fair value of the debt are classified in other expenses as a change in the fair value of financial instruments in the consolidated statements of operations. At March 31, 2016, the fair value of our notes payable is approximately $63.7 million, compared to the carrying value of $60.9 million. (3) Derivative liabilities: Derivative liabilities are related to certain outstanding warrants which are recorded at fair value. Derivative liabilities totaling $63,000 as of March 31, 2016 and December 31, 2015 were included in other liabilities on the consolidated balance sheets. The assumptions used to calculate fair value as of March 31, 2016 and December 31, 2015 included volatility, a risk-free rate and expected dividends. In addition, we considered non-performance risk and determined that such risk is minimal. Unrealized gains and losses on the derivatives are classified in other expenses as a change in the fair value of financial instruments in the statements of operations. See Note 3.
Revenue Recognition	c. Revenue Recognition: We currently generate revenue primarily from sales of Lymphoseek ® We earn additional revenues based on a percentage of the actual net revenues achieved by Cardinal Health on sales to end customers made during each fiscal year. The amount we charge Cardinal Health related to end customer sales of Lymphoseek are subject to a retroactive annual adjustment. To the extent that we can reasonably estimate the end-customer prices received by Cardinal Health, we record sales based upon these estimates at the time of sale. If we are unable to reasonably estimate end customer sales prices related to products sold, we record revenue related to these product sales at the minimum (i.e., floor) price provided for under our distribution agreement with Cardinal Health. During the three-month periods ended March 31, 2016 and 2015, over 99% of Lymphoseek sales were made to Cardinal Health. As of March 31, 2016, approximately 98% of accounts and other receivables were due from Cardinal Health. We also earn revenues related to our licensing and distribution agreements. The terms of these agreements may include payment to us of non-refundable upfront license fees, funding or reimbursement of research and development efforts, milestone payments if specified objectives are achieved, and/or royalties on product sales. We evaluate all deliverables within an arrangement to determine whether or not they provide value on a stand-alone basis. We recognize a contingent milestone payment as revenue in its entirety upon our achievement of a substantive milestone if the consideration earned from the achievement of the milestone (i) is consistent with performance required to achieve the milestone or the increase in value to the delivered item, (ii) relates solely to past performance and (iii) is reasonable relative to all of the other deliverables and payments within the arrangement. We received a non-refundable upfront cash payment of $2.0 million from SpePharm AG upon execution of the SpePharm License Agreement in March 2015. We have determined that the license and other non-contingent deliverables do not have stand-alone value because the license could not be deemed to be fully delivered for its intended purpose unless we perform our other obligations, including specified development work. Accordingly, they do not meet the separation criteria, resulting in these deliverables being considered a single unit of account. As a result, revenue relating to the upfront cash payment was deferred and is being recognized on a straight-line basis over the estimated obligation period of two years. We generate additional revenue from grants to support various product development initiatives. We generally recognize grant revenue when expenses reimbursable under the grants have been paid and payments under the grants become contractually due. Lastly, we recognize revenues from the provision of services to R-NAV and its subsidiaries. See Note 7.
Recent Accounting Pronouncements	d. Recent Accounting Pronouncements: In March 2016, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) No. 2016-08, Revenue from Contracts with Customers – Principal versus Agent Considerations (Reporting Revenue Gross versus Net) . ASU 2016-08 does not change the core principle of the guidance, rather it clarifies the implementation guidance on principal versus agent considerations. ASU 2016-08 clarifies the guidance in ASU No. 2014-09, Revenue from Contracts with Customers (Topic 606) , which is not yet effective. The effective date and transition requirements for ASU 2016-08 are the same as for ASU 2014-09, which was deferred by one year by ASU No. 2015-14, Revenue from Contracts with Customers – Deferral of the Effective Date . Public business entities should adopt the new revenue recognition standard for annual reporting periods beginning after December 15, 2017, including interim periods within that year. Early adoption is permitted only as of annual reporting periods beginning after December 15, 2016, including interim periods within that year. We are currently evaluating the potential impact that the adoption of ASU 2014-09 may have on our consolidated financial statements. In March 2016, the FASB issued ASU No. 2016-09, Compensation – Stock Compensation In April 2016, the FASB issued ASU No. 2016-10, Revenue from Contracts with Customers – Identifying Performance Obligations and Licensing Revenue from Contracts with Customers (Topic 606) Revenue from Contracts with Customers – Deferral of the Effective Date

Fair Value (Tables)

Fair Value (Tables)	3 Months Ended
	Mar. 31, 2016
Fair Value Disclosures [Abstract]
Fair Value of Liabilities Measured on Recurring Basis	The following tables set forth, by level, financial liabilities measured at fair value on a recurring basis: Liabilities Measured at Fair Value on a Recurring Basis as of March 31, 2016 Description Quoted Active Markets for Identical Liabilities (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Total Platinum notes payable conversion option $ — $ — $ 1,886,521 $ 1,886,521 Liability related to MT warrants — — 63,000 63,000 Liabilities Measured at Fair Value on a Recurring Basis as of December 31, 2015 Description Quoted Prices in Active Markets for Identical Liabilities (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Total Platinum notes payable conversion option $ — $ — $ 3,011,880 $ 3,011,880 Liability related to MT warrants — — 63,000 63,000

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	3 Months Ended
	Mar. 31, 2016
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Summary of Stock Options Activity	A summary of the status of our stock options as of March 31, 2016, and changes during the three-month period then ended, is presented below: Three Months Ended March 31, 2016 Number of Options Weighted Average Exercise Price Weighted Average Remaining Contractual Life Aggregate Intrinsic Value Outstanding at beginning of period 5,437,064 $ 1.96 Granted 366,457 0.96 Exercised — — Canceled and Forfeited (112,000 ) 1.86 Expired (299,000 ) 2.42 Outstanding at end of period 5,392,521 $ 1.87 7.5 years $ 104,600 Exercisable at end of period 3,337,968 $ 2.03 6.8 years $ 101,276
Schedule of Nonvested Restricted Stock Activity	A summary of the status of our unvested restricted stock as of March 31, 2016, and changes during the three-month period then ended, is presented below: Three Months Ended March 31, 2016 Number of Shares Weighted Average Grant-Date Fair Value Unvested at beginning of period 361,000 $ 1.69 Granted — — Vested (66,000 ) 1.65 Forfeited (161,000 ) 1.75 Unvested at end of period 134,000 $ 1.63

Inventory (Tables)

Inventory (Tables)	3 Months Ended
	Mar. 31, 2016
Inventory Disclosure [Abstract]
Schedule of Inventory	The components of inventory as of March 31, 2016 and December 31, 2015 are as follows: March 31, 2016 December 31, 2015 (unaudited) Materials $ 30,000 $ 330,000 Work-in-process 108,518 392,457 Finished goods 938,324 275,168 Reserves (177,906 ) (344,719 ) Total $ 898,936 $ 652,906

Segments (Tables)

Segments (Tables)	3 Months Ended
	Mar. 31, 2016
Segment Reporting [Abstract]
Schedule of segment reporting information	The information in the following tables is derived directly from each reportable segment’s financial reporting. Three Months Ended March 31, 2016 Diagnostics Therapeutics Corporate Total Lymphoseek sales revenue: United States (1) $ 3,771,420 $ — $ — $ 3,771,420 International 11,260 — — 11,260 Lymphoseek license revenue 254,050 — — 254,050 Grant and other revenue 685,825 — — 685,825 Total revenue 4,722,555 — — 4,722,555 Cost of goods sold, excluding depreciation and amortization 494,639 — — 494,639 Research and development expenses, excluding depreciation and amortization 2,417,720 241,800 — 2,659,520 Selling, general and administrative expenses, excluding depreciation and amortization (2) 1,012,106 (598 ) 2,975,850 3,987,358 Depreciation and amortization (3) 40,290 — 109,302 149,592 Loss from operations (4) 757,800 (241,202 ) (3,085,152 ) (2,568,554 ) Other income (expense), excluding equity in the loss of R-NAV, LLC (5) — — (1,105,456 ) (1,105,456 ) Equity in the loss of R-NAV, LLC — — (12,239 ) (12,239 ) Net loss 757,800 (241,202 ) (4,202,847 ) (3,686,249 ) Total assets, net of depreciation and amortization: United States 4,109,640 16,515 7,774,939 11,901,094 International 380,982 — 1,605 382,587 Capital expenditures — — 1,847 1,847 Three Months Ended March 31, 2015 Diagnostics Therapeutics Corporate Total Lymphoseek sales revenue: United States (1) $ 1,831,022 $ — $ — $ 1,831,022 International 4,400 — — 4,400 Lymphoseek license revenue 83,333 — — 83,333 Grant and other revenue 189,701 — — 189,701 Total revenue 2,108,456 — — 2,108,456 Cost of goods sold, excluding depreciation and amortization 420,551 — — 420,551 Research and development expenses, excluding depreciation and amortization 3,890,724 86,014 — 3,976,738 Selling, general and administrative expenses, excluding depreciation and amortization (2) 2,042,175 14,366 3,320,861 5,377,402 Depreciation and amortization (3) 33,056 — 116,766 149,822 Loss from operations (4) (4,278,050 ) (100,380 ) (3,437,627 ) (7,816,057 ) Other income (expense), excluding equity in the loss of R-NAV, LLC (5) — — 787,059 787,059 Equity in the loss of R-NAV, LLC — — (262,227 ) (262,227 ) Net loss (4,278,050 ) (100,380 ) (2,912,795 ) (7,291,225 ) Total assets, net of depreciation and amortization: United States 3,333,851 7,409 7,077,673 10,418,933 International 496,311 — 2,665 498,976 Capital expenditures — — — — (1) All sales to Cardinal Health are made in the United States; Cardinal distributes the product throughout the U.S. through its network of nuclear pharmacies. (2) General and administrative expenses, excluding depreciation and amortization, represent costs that relate to the general administration of the Company and as such are not currently allocated to our individual reportable segments. Marketing and selling expenses are allocated to our individual reportable segments. (3) (4) Loss from operations does not reflect the allocation of certain selling, general and administrative expenses, excluding depreciation and amortization, to our individual reportable segments. (5) Amounts consist primarily of interest income, interest expense, changes in fair value of financial instruments, and losses on debt extinguishment, which are not currently allocated to our individual reportable segments.

Summary of Significant Accoun27

Summary of Significant Accounting Policies (Narrative) (Details) - USD ($)	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Accounting Policies [Line Items]
Fair value of notes payable	$ 63,700,000		$ 63,700,000
Notes payable	60,900,000		60,900,000
Derivative liabilities	$ 63,000		$ 63,000		$ 63,000
Non-refundable upfront cash payment received		$ 2,000,000
Deferred revenue recognition period			2 years
Cardinal Health [Member] | Customer Concentration Risk [Member] | Accounts and Other Receivable [Member]
Accounting Policies [Line Items]
Concentration risk, percentage	98.00%
Cardinal Health [Member] | Customer Concentration Risk [Member] | Minimum [Member] | Lymphoseek sales [Member]
Accounting Policies [Line Items]
Concentration risk, percentage			99.00%	99.00%

Liquidity (Narrative) (Details)

Liquidity (Narrative) (Details) - Capital Royalty Partners II LP [Member] - USD ($)	3 Months Ended	12 Months Ended
	Mar. 31, 2016	Dec. 31, 2015	May. 15, 2015
Liquidity [Line Items]
Liquidity minimum	$ 5,000,000		$ 5,000,000
Minimum sales revenue target	$ 22,500,000	$ 11,000,000
Debt instrument default interest rate percentage	18.00%
Cure right ratio	2.50%

Fair Value (Narrative) (Details

Fair Value (Narrative) (Details) - USD ($)	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Derivative liabilities	$ 63,000		$ 63,000
Recurring [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Platinum notes payable	10,672,265
Derivative liabilities	63,000		63,000
Transfers into Level 2	0	$ 0
Transfers out of Level 2	0	0
Recurring [Member] | Quoted Prices in Active Markets for Identical Liabilities (Level 1) [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Liabilities at fair value	0	0
Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Derivative liabilities	63,000		$ 63,000
Decrease in fair value of Level 3 liabilities	$ (1,100,000)	$ (1,700,000)

Fair Value (Details)

Fair Value (Details) - USD ($)	Mar. 31, 2016	Dec. 31, 2015
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Liability related to MT warrants	$ 63,000	$ 63,000
Recurring [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Platinum notes payable conversion option	1,886,521	3,011,880
Liability related to MT warrants	63,000	63,000
Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Platinum notes payable conversion option	1,886,521	3,011,880
Liability related to MT warrants	$ 63,000	$ 63,000

Stock-Based Compensation (Narra

Stock-Based Compensation (Narrative) (Details) - USD ($)	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense including reversals of expense for forfeited or cancelled awards	$ 341,000	$ 1,100,000
Number of restricted stock units vested during period	66,000
Number of unvested restricted stock units forfeited during period	161,000
Unrecognized compensation expense, Nonvested awards	$ 815,000
Unrecognized compensation cost, Period for Recognition	1 year 8 months 12 days
Unvested Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of unvested restricted stock units forfeited during period	161,000
Unvested Restricted Stock [Member] | Non-Employee Directors[Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of restricted stock units vested during period	66,000
Aggregate fair value of restricted stock vested	$ 63,360

Stock-Based Compensation (Summa

Stock-Based Compensation (Summary of Stock Options Activity) (Details)	3 Months Ended
	Mar. 31, 2016USD ($)$ / sharesshares
Number of Options
Outstanding at beginning of period | shares	5,437,064
Granted | shares	366,457
Canceled and Forfeited | shares	(112,000)
Expired | shares	(299,000)
Outstanding at end of period | shares	5,392,521
Exercisable at end of period | shares	3,337,968
Weighted Average Exercise Price
Outstanding at beginning of period, dollars per share | $ / shares	$ 1.96
Granted, dollars per share | $ / shares	0.96
Canceled and Forfeited, dollars per share | $ / shares	1.86
Expired, dollars per share | $ / shares	2.42
Outstanding at end of period, dollars per share | $ / shares	1.87
Exercisable at end of period, dollars per share | $ / shares	$ 2.03
Weighted Average Remaining Contractual Life (years)
Outstanding at end of period	7 years 6 months
Exercisable at end of period	6 years 9 months 18 days
Aggregate Intrinsic Value
Outstanding at end of period | $	$ 104,600
Exercisable at end of period | $	$ 101,276

Stock-Based Compensation (Sum33

Stock-Based Compensation (Summary of Unvested Restricted Stock) (Details)	3 Months Ended
	Mar. 31, 2016$ / sharesshares
Number of Shares
Unvested at beginning of period, shares | shares	361,000
Vested, shares | shares	(66,000)
Forfeited, shares | shares	(161,000)
Unvested at end of period, shares | shares	134,000
Weighted Average Grant-Date Fair Value
Unvested at beginning of period, USD per share | $ / shares	$ 1.69
Vested, USD per share | $ / shares	1.65
Forfeited,USD per share | $ / shares	1.75
Unvested at end of period, USD per share | $ / shares	$ 1.63

Earnings (Loss) Per Share (Narr

Earnings (Loss) Per Share (Narrative) (Details) - shares	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Stock Options Warrants Convertible Debt And Convertible Preferred Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares excluded in determining basic and diluted loss per share	15,100,000	20,100,000
Unvested Restricted Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares excluded in determining basic and diluted loss per share	134,000	671,500

Inventory - Components of Inven

Inventory - Components of Inventory, Net of Reserves (Details) - USD ($)	Mar. 31, 2016	Dec. 31, 2015
Inventory Disclosure [Abstract]
Inventory, Raw Materials, Gross	$ 30,000	$ 330,000
Inventory, Work in Process, Gross	108,518	392,457
Inventory, Finished Goods, Gross	938,324	275,168
Inventory Valuation Reserves	(177,906)	(344,719)
Total	$ 898,936	$ 652,906

Inventory (Narrative) (Details)

Inventory (Narrative) (Details)	3 Months Ended
	Mar. 31, 2015USD ($)
Production Materials [Member]
Inventory [Line Items]
Inventory write-down	$ 120,000
Lymphoseek Inventory Used in Development Activity [Member]
Inventory [Line Items]
Inventory write-down	$ 37,000

Investment in R-NAV, LLC (Detai

Investment in R-NAV, LLC (Details) - USD ($)	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Schedule Of Equity Method Investments [Line Items]
Equity in loss of R-NAV, LLC	$ 12,239	$ 262,227
R-NAV [Member]
Schedule Of Equity Method Investments [Line Items]
Ownership percentage	27.00%
Equity in loss of R-NAV, LLC	$ 12,239	262,227
Carrying value of investment	0		$ 0
Commitment to provide services	500,000
Cost of services provided	12,000	$ 21,000
Remaining commitment to provide services	$ 385,000

Notes Payable (Narrative) (Deta

Notes Payable (Narrative) (Details) - USD ($)	3 Months Ended		12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015	Apr. 07, 2016	May. 31, 2015	May. 15, 2015	Jul. 31, 2012
Debt Instrument [Line Items]
Compounded interest on notes payable	$ 824,952
Notes payable	60,900,000
Change in fair value of financial instruments	1,125,359	$ 1,727,103
Lymphoseek sales revenue	3,782,680	1,835,422	$ 10,300,000
Notes payable, current	50,179,537		333,333
Interest expense	2,200,000	967,000
Interest expense recorded related to amortization	72,875	212,813
R-NAV [Member]
Debt Instrument [Line Items]
Notes payable, current	333,333
Platinum Credit Facility [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity, amount							$ 50,000,000
Current borrowing capacity							$ 35,000,000
Compounded interest on notes payable	306,000
Notes payable	8,800,000
Remaining borrowing capacity	27,300,000
Unused additional borrowing capacity	15,000,000
Platinum notes payable	1,900,000
Change in fair value of financial instruments	(1,100,000)	$ (1,700,000)
Estimated fair value	10,700,000
Capital Royalty Partners II LP [Member]
Debt Instrument [Line Items]
Compounded interest on notes payable	519,000
Notes payable	$ 51,800,000
Debt instrument face amount					$ 50,000,000
Debt Instrument, unused borrowing capacity					$ 10,000,000
Payment terms	2 years
Debt discount related to lender fees and other costs						$ 2,200,000
Notes payable, discounts	$ 2,000,000
End-of-term fee amount	1,000,000					1,000,000
EBITDA, less than	5,000,000
Minimum sales revenue target	$ 22,500,000		11,000,000
Minimum sales revenue target in 2020						45,000,000
Cure right ratio	2.50%
Liquidity minimum	$ 5,000,000					$ 5,000,000
Debt instrument default interest rate percentage	18.00%
Reduced minimum sales revenue target in 2015			$ 10,000,000
Capital Royalty Partners II LP [Member] | Subsequent Event [Member]
Debt Instrument [Line Items]
Debt instrument default interest rate percentage				18.00%

Commitments and Contingencies (

Commitments and Contingencies (Narrative) (Details) - USD ($)	3 Months Ended		12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015	Apr. 07, 2016
Loss Contingencies [Line Items]
Lymphoseek sales revenue	$ 3,782,680	$ 1,835,422	$ 10,300,000
Capital Royalty Partners II LP [Member]
Loss Contingencies [Line Items]
Debt instrument default interest rate percentage	18.00%
Minimum sales revenue target	$ 22,500,000		11,000,000
Reduced minimum sales revenue target in 2015			$ 10,000,000
Capital Royalty Partners II LP [Member] | Subsequent Event [Member]
Loss Contingencies [Line Items]
Debt instrument default interest rate percentage				18.00%

Equity Instruments (Narrative)

Equity Instruments (Narrative) (Details)	3 Months Ended
	Mar. 31, 2016USD ($)shares
Class Of Stock [Line Items]
Stock issued during period value	$ 20,640
Common Stock [Member]
Class Of Stock [Line Items]
Shares of common stock issued | shares	16,918
Stock issued during period value	$ 17
Board of Directors [Member] | Common Stock [Member]
Class Of Stock [Line Items]
Shares of common stock issued | shares	16,918
Stock issued during period value	$ 21,000

Stock Warrants (Narrative) (Det

Stock Warrants (Narrative) (Details)	3 Months Ended
	Mar. 31, 2016$ / sharesshares
Class of Warrant or Right [Line Items]
Warrants outstanding (shares) | shares	11,700,000
Common Stock [Member] | Macrophage Therapeutics [Member]
Class of Warrant or Right [Line Items]
Exercise price of warrant issued, dollars per share	$ 2,000
Outstanding number of warrant to be converted to common stock | shares	300
Minimum [Member]
Class of Warrant or Right [Line Items]
Exercise price of warrant issued, dollars per share	$ 0.01
Warrant, Outstanding Term	1 year
Maximum [Member]
Class of Warrant or Right [Line Items]
Exercise price of warrant issued, dollars per share	$ 3.04
Warrant, Outstanding Term	19 years
Weighted Average [Member]
Class of Warrant or Right [Line Items]
Exercise price of warrant issued, dollars per share	$ 0.38

Income Taxes (Narrative) (Detai

Income Taxes (Narrative) (Details) - USD ($)	Mar. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Liability for uncertain tax positions	$ 0	$ 0

Segments (Narrative) (Details)

Segments (Narrative) (Details)	3 Months Ended
	Mar. 31, 2016Segment
Segment Reporting [Abstract]
Number of reporting segments	2

Segments (Details)

Segments (Details) - USD ($)	3 Months Ended		12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Segment Reporting Information [Line Items]
Lymphoseek sales revenue	$ 3,782,680	$ 1,835,422	$ 10,300,000
Lymphoseek license revenue	254,050	83,333
Grant and other revenue	685,825	189,701
Total revenue	4,722,555	2,108,456
Cost of goods sold, excluding depreciation and amortization	494,639	420,551
Research and development expenses, excluding depreciation and amortization	2,659,520	3,976,738
Selling, general and administrative expenses, excluding depreciation and amortization	3,987,358	5,377,402
Depreciation and amortization	149,592	149,822
Loss from operations	(2,568,554)	(7,816,057)
Other income (expense), excluding equity in the loss of R-NAV, LLC	(1,105,456)	787,059
Equity in the loss of R-NAV, LLC	(12,239)	(262,227)
Net loss	(3,686,249)	(7,291,225)
Total assets, net of depreciation and amortization	12,283,681		$ 14,964,513
Payments to Acquire Property, Plant, and Equipment	1,847
Corporate [Member]
Segment Reporting Information [Line Items]
Selling, general and administrative expenses, excluding depreciation and amortization	2,975,850	3,320,861
Depreciation and amortization	109,302	116,766
Loss from operations	(3,085,152)	(3,437,627)
Other income (expense), excluding equity in the loss of R-NAV, LLC	(1,105,456)	787,059
Equity in the loss of R-NAV, LLC	(12,239)	(262,227)
Net loss	(4,202,847)	(2,912,795)
Payments to Acquire Property, Plant, and Equipment	1,847
United States [Member]
Segment Reporting Information [Line Items]
Lymphoseek sales revenue	3,771,420	1,831,022
Total assets, net of depreciation and amortization	11,901,094	10,418,933
United States [Member] | Corporate [Member]
Segment Reporting Information [Line Items]
Total assets, net of depreciation and amortization	7,774,939	7,077,673
International [Member]
Segment Reporting Information [Line Items]
Lymphoseek sales revenue	11,260	4,400
Total assets, net of depreciation and amortization	382,587	498,976
International [Member] | Corporate [Member]
Segment Reporting Information [Line Items]
Total assets, net of depreciation and amortization	1,605	2,665
Diagnostics [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Lymphoseek license revenue	254,050	83,333
Grant and other revenue	685,825	189,701
Total revenue	4,722,555	2,108,456
Cost of goods sold, excluding depreciation and amortization	494,639	420,551
Research and development expenses, excluding depreciation and amortization	2,417,720	3,890,724
Selling, general and administrative expenses, excluding depreciation and amortization	1,012,106	2,042,175
Depreciation and amortization	40,290	33,056
Loss from operations	757,800	(4,278,050)
Net loss	757,800	(4,278,050)
Diagnostics [Member] | United States [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Lymphoseek sales revenue	3,771,420	1,831,022
Total assets, net of depreciation and amortization	4,109,640	3,333,851
Diagnostics [Member] | International [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Lymphoseek sales revenue	11,260	4,400
Total assets, net of depreciation and amortization	380,982	496,311
Therapeutics [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Research and development expenses, excluding depreciation and amortization	241,800	86,014
Selling, general and administrative expenses, excluding depreciation and amortization	(598)	14,366
Loss from operations	(241,202)	(100,380)
Net loss	(241,202)	(100,380)
Therapeutics [Member] | United States [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Total assets, net of depreciation and amortization	$ 16,515	$ 7,409

Segments (Parenthetical) (Detai

Segments (Parenthetical) (Details) - USD ($)	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Segment Reporting Information [Line Items]
Depreciation and amortization	$ 149,592	$ 149,822
Cost of Goods Sold [Member]
Segment Reporting Information [Line Items]
Depreciation and amortization	40,290	28,506
Research and Development [Member]
Segment Reporting Information [Line Items]
Depreciation and amortization	0	4,550
Selling, General and Administrative Expenses [Member]
Segment Reporting Information [Line Items]
Depreciation and amortization	$ 109,302	$ 116,765

Supplemental Disclosure for S46

Supplemental Disclosure for Statements of Cash Flows (Details) - USD ($)	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Supplemental Cash Flow Elements [Abstract]
Cash paid during the period for interest	$ 1,300,000	$ 701,000
Issued stock to 401(k) plan, shares		68,157
Issued stock to 401(k) plan for employer matching contributions	$ 0	$ 117,099

Subsequent Event (Narrative) (D

Subsequent Event (Narrative) (Details) - USD ($)	3 Months Ended		12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015	Apr. 07, 2016
Subsequent Event [Line Items]
Lymphoseek sales revenue	$ 3,782,680	$ 1,835,422	$ 10,300,000
Capital Royalty Partners II LP [Member]
Subsequent Event [Line Items]
Debt instrument default interest rate percentage	18.00%
Minimum sales revenue target in 2015	$ 22,500,000		11,000,000
Reduced minimum sales revenue target in 2015			$ 10,000,000
Capital Royalty Partners II LP [Member] | Subsequent Event [Member]
Subsequent Event [Line Items]
Debt instrument default interest rate percentage				18.00%