ImmunityBio (IBRX) 10-Q 10 Nov 16 2016 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2016	Nov. 03, 2016
Document Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2016
Document Fiscal Year Focus	2,016
Document Fiscal Period Focus	Q3
Trading Symbol	NK
Entity Registrant Name	NANTKWEST, INC.
Entity Central Index Key	1,326,110
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Entity Common Stock, Shares Outstanding		82,375,489

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Current assets:
Cash and cash equivalents	$ 31,404	$ 175,908
Prepaid expenses and other current assets	5,215	3,322
Marketable securities	177,852	118,310
Total current assets	214,471	297,540
Marketable securities, noncurrent	94,655	55,135
Property and equipment, net	16,475	5,523
Intangible assets, net	5,948	7,292
Other assets	862	1,359
Total assets	332,411	366,849
Current liabilities:
Accounts payable	2,245	2,085
Accrued expenses	5,910	2,575
Due to related parties	1,853	1,352
Other current liabilities	224	136
Total current liabilities	10,232	6,148
Build-to-suit liability, less current portion	5,313	2,468
Financing obligation, less current portion	2,390	0
Deferred rent	2,488	845
Deferred revenue	192	228
Deferred tax liability	883	1,165
Other liabilities	22	0
Total liabilities	21,520	10,854
Commitments and contingencies (Note 6)
Stockholders’ equity
Common stock	8	8
Additional paid-in capital	669,624	606,555
Accumulated other comprehensive income (loss)	135	(192)
Accumulated deficit	(358,876)	(250,376)
Total stockholders’ equity	310,891	355,995
Total liabilities and stockholders’ equity	$ 332,411	$ 366,849

Condensed Consolidated Balance3

Condensed Consolidated Balance Sheets (Parenthetical) - Common Stock Class Undefined - $ / shares	Sep. 30, 2016	Dec. 31, 2015
Common stock, par value	$ 0.0001	$ 0.0001
Common stock, shares authorized	500,000,000	500,000,000
Common stock, shares issued	82,375,489	81,311,686
Common stock, shares outstanding	82,375,489	81,311,686

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Income Statement [Abstract]
Revenue	$ 12	$ 10	$ 30	$ 222
Operating expenses:
Research and development	8,364	4,657	19,708	7,364
Selling, general and administrative	24,423	41,810	79,678	201,810
Total operating expenses	32,787	46,467	99,386	209,174
Loss from operations	(32,775)	(46,457)	(99,356)	(208,952)
Other income (expense):
Investment income, net	795	81	2,302	146
Change in fair value of warrant liability	0	0	0	(1,366)
Interest expense	(29)	0	(29)	0
Other income, net	60	64	89	119
Total other income (expense)	826	145	2,362	(1,101)
Loss before income taxes	(31,949)	(46,312)	(96,994)	(210,053)
Income tax (benefit) expense, net	(52)	0	(423)	1
Net loss	$ (31,897)	$ (46,312)	$ (96,571)	$ (210,054)
Net loss per share:
Basic and diluted	$ (0.39)	$ (0.59)	$ (1.18)	$ (3.07)
Weighted average number of shares during the period:
Basic and diluted	82,154,219	77,837,586	82,019,203	68,316,004

Condensed Consolidated Stateme5

Condensed Consolidated Statements of Comprehensive Loss (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Statement Of Income And Comprehensive Income [Abstract]
Net loss	$ (31,897)	$ (46,312)	$ (96,571)	$ (210,054)
Other comprehensive income, net of income taxes:
Net unrealized gain (loss) on available-for-sale securities	(241)	0	405	0
Reclassification of net realized gains on available-for-sale securities included in net loss	(48)	0	(78)	0
Total other comprehensive income (loss)	(289)	0	327	0
Comprehensive loss	$ (32,186)	$ (46,312)	$ (96,244)	$ (210,054)

Condensed Consolidated Stateme6

Condensed Consolidated Statement of Shareholders' Equity (Unaudited) - 9 months ended Sep. 30, 2016 - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Other Comprehensive Income (Loss)	Accumulated Deficit
Beginning Balance at Dec. 31, 2015	$ 355,995	$ 8	$ 606,555	$ (192)	$ (250,376)
Beginning Balance, Shares at Dec. 31, 2015		81,311,686
Exercise of stock options	1,003	$ 0	1,003	0	0
Exercise of stock options, Shares		2,188,204
Stock-based compensation expense	62,586	$ 0	62,586	0	0
Vesting of restricted stock units		514,316
Employee payroll taxes withheld related to vesting of restricted stock units	(592)	$ 0	(592)	0	0
Employee payroll taxes withheld related to vesting of restricted stock units, Shares		(85,191)
Exercise of warrants	41	$ 0	41	0	0
Exercise of warrants, Shares		40,514
Change in accounting principle - ASU 2016-09 forfeiture adjustment	0	$ 0	31	0	(31)
Repurchase of common stock	$ (11,898)	$ 0	0	0	(11,898)
Repurchase of common stock, Shares	(1,594,040)	(1,594,040)
Other comprehensive income, net	$ 327	$ 0	0	327	0
Net loss	(96,571)	0	0	0	(96,571)
Ending Balance at Sep. 30, 2016	$ 310,891	$ 8	$ 669,624	$ 135	$ (358,876)
Ending Balance, Shares at Sep. 30, 2016		82,375,489

Condensed Consolidated Stateme7

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Operating activities:
Net loss	$ (96,571)	$ (210,054)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	1,768	981
Stock-based compensation expense	62,586	189,815
Deferred income tax benefit	(423)	0
Change in value of warrant liability	0	1,366
Loss incurred by Inex Bio	0	57
Loss on disposal of assets	18	0
Amortization of net premiums on marketable securities	1,567	0
Non-cash interest items, net	(273)	0
Gain on sales of marketable securities	(118)	0
Gain on settlement of note payable	0	(133)
Changes in operating assets and liabilities:
Prepaid and other current assets	(1,380)	(1,463)
Other assets	75	(1,193)
Accounts payable	321	3,815
Accrued expenses and other liabilities	2,454	984
Due to related parties	501	1,225
Deferred rent	1,650	345
Deferred revenue	(15)	(106)
Net cash used in operating activities	(27,840)	(14,361)
Investing activities:
Purchases of property and equipment	(5,202)	(1,286)
Purchase of Inex Bio Inc., net of cash acquired	0	(1,818)
Purchases of marketable securities	(207,891)	0
Sales/maturities of marketable securities	107,885	0
Net cash used in investing activities	(105,208)	(3,104)
Financing activities:
Proceeds from debt and equity offerings, net of issuance costs	0	316,189
Repayments of financing obligations	(10)	0
Repayments of notes payable	0	(132)
Proceeds from exercise of stock options and warrants	1,044	8,183
Repurchase of common stock	(11,898)	(4,798)
Employee payroll taxes paid related to net share settlement of restricted stock units	(592)	(2,415)
Net cash (used in) provided by financing activities	(11,456)	317,027
Effect of exchange rate changes on cash and cash equivalents	0	(50)
Net increase (decrease) in cash and cash equivalents	(144,504)	299,512
Cash and cash equivalents, beginning of period	175,908	59,104
Cash and cash equivalents, end of period	31,404	358,616
Cash paid during the period for:
Interest	29	0
Income taxes	1	6
Supplemental disclosure of non-cash investing and financing activities:
Estimated fair value of buildings under build-to-suit leases	5,139	2,740
Lease incentives	239	0
Property and equipment purchases included in accounts payable and accrued expenses	1,092	0
Cashless exercise of stock options and warrants	456	1,773
Unrealized gain on marketable securities	506	0
Inex Bio Inc
Supplemental disclosure of non-cash investing and financing activities:
Issuance of warrants in Inex Bio, Inc. acquisition	$ 0	$ 5,170

Description of Business and Bas

Description of Business and Basis of Presentation	9 Months Ended
	Sep. 30, 2016
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Description of Business and Basis of Presentation	1. Description of Business and Basis of Presentation Organization NantKwest, Inc. (the Company) was incorporated in Illinois on October 7, 2002 under the name ZelleRx Corporation. On January 22, 2010, the Company changed its name to Conkwest, Inc., and on July 10, 2015, the Company changed its name to NantKwest, Inc. In March 2014, the Company redomesticated from the State of Illinois to the State of Delaware and the Illinois Company ceased to exist. The Company is a biotechnology company headquartered in San Diego, California with certain operations in Culver City and El Segundo, California and Woburn, Massachusetts. The Company is commercially developing targeted direct-acting immunotherapeutic agents for a variety of clinical conditions. The Company holds the exclusive right to commercialize activated natural killer (aNK) cells, a commercially viable natural killer cell-line, and a variety of genetically modified derivatives capable of killing cancer and virally infected cells. The Company owns corresponding U.S. and foreign composition and methods-of-use patents and applications covering the clinical use of aNK cells as a therapeutic to treat a spectrum of clinical conditions. The Company also licensed exclusive commercial rights to a portfolio of CD16 bearing aNK cells along with the corresponding U.S. and foreign composition and methods-of-use patents and applications covering the non-clinical use in laboratory testing of monoclonal antibodies as well as clinical use as a therapeutic to treat cancers in combination with antibody products. The Company has licensed or sub-licensed its cell lines and intellectual property to numerous pharmaceutical and biotechnology companies for such non-clinical uses. The Company retains exclusive worldwide rights to clinical and research data, intellectual property and know-how developed with the Company’s aNK cells, as well as the only clinical grade master cell bank. Unaudited Interim The accompanying condensed consolidated balance sheet at September 30, 2016, the condensed consolidated statements of operations and comprehensive loss for the three and nine months ended September 30, 2016, the condensed consolidated statements of cash flows for the nine months ended September 30, 2016, and the condensed consolidated statement of stockholders’ equity for the nine months ended September 30, 2016 have been prepared by management of the Company and have not been audited. These financial statements have been prepared on the same basis as the audited consolidated financial statements for the fiscal year ended December 31, 2015 and, in the opinion of management, include all adjustments (consisting only of normal recurring adjustments) necessary for a fair statement of the Company’s results for the periods presented. These financial statements should be read in conjunction with the financial statements and notes thereto for the fiscal year ended December 31, 2015 included in the Company’s Annual Report on Form 10-K. Interim operating results are not necessarily indicative of operating results for the full year. The year-end condensed consolidated balance sheet data was derived from audited financial statements, but does not include all disclosures required by accounting principles generally accepted in the United States of America (GAAP). Principles of Consolidation The Company’s condensed consolidated financial statements include the accounts of the Company and its wholly-owned subsidiary, Inex Bio, Inc., and have been prepared in accordance with GAAP. All intercompany amounts have been eliminated. Prior Restatement The Company identified material errors in stock compensation expense, property and equipment and build-to-suit liability balances along with various other immaterial errors during the fourth quarter of fiscal 2015 related to prior periods. The correction of these errors resulted in the restatement of previously reported unaudited condensed consolidated financial statements for the second and third quarters of fiscal 2015, which were included in the Annual Report on Form 10-K for the year ended December 31, 2015. Accordingly, within this Quarterly Report on Form 10-Q, the unaudited condensed consolidated statement of operations for the three and nine months ended September 30, 2015 and the unaudited condensed consolidated statement of cash flows for the nine months ended September 30, 2015 have been labeled Restated. Liquidity As of September 30, 2016, the Company had an accumulated deficit of approximately $358.9 million. The Company also had negative cash flow from operations of approximately $27.8 million during the nine months ended September 30, 2016. The Company expects that it will likely need additional capital to further fund development of, and seek regulatory approvals for, its product candidates, and begin to commercialize any approved products. The Company is currently focused primarily on the development of immunotherapeutic treatments for cancers and debilitating viral infections using targeted cancer killing cell lines, and believes such activities will result in the Company’s continued incurrence of significant research and development and other expenses related to those programs. If the clinical trials for any of the Company’s product candidates fail or produce unsuccessful results and those product candidates do not gain regulatory approval, or if any of the Company’s product candidates, if approved, fails to achieve market acceptance, the Company may never become profitable. Even if the Company achieves profitability in the future, it may not be able to sustain profitability in subsequent periods. The Company intends to cover its future operating expenses through cash and cash equivalents and marketable securities on hand and through a combination of equity offerings, debt financings, government or other third-party funding, marketing and distribution arrangements and other collaborations, strategic alliances and licensing arrangements. Additional financing may not be available to the Company when needed and, if available, financing may not be obtained on terms favorable to the Company or its stockholders. While the Company expects its existing cash and cash equivalents and marketable securities will enable it to fund operations and capital expenditure requirements for the foreseeable future, it may not have sufficient funds to reach commercialization. Failure to obtain adequate financing when needed may require the Company to delay, reduce, limit or terminate some or all of its development programs or future commercialization efforts or grant rights to develop and market product candidates that the Company might otherwise prefer to develop and market itself which could adversely affect the Company’s ability to operate as a going concern. If the Company raises additional funds from the issuance of equity securities, substantial dilution to existing stockholders may result. If the Company raises additional funds by incurring debt financing, the terms of the debt may involve significant cash payment obligations as well as covenants and specific financial ratios that may restrict the Company’s ability to operate its business.

Summary of Significant Accounti

Summary of Significant Accounting Policies	9 Months Ended
	Sep. 30, 2016
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	2. Summary of Significant Accounting Policies With the exception of the preclinical and clinical trial accrual, stock repurchases and stock-based compensation policies discussed below, there have been no significant changes to the items that the Company disclosed as its summary of significant accounting policies in the Annual Report on Form 10-K for the year ended December 31, 2015. Preclinical and As part of the process of preparing the financial statements, the Company is required to estimate expenses resulting from obligations under contracts with vendors, clinical research organizations and consultants. The financial terms of these contracts vary and may result in payment flows that do not match the periods over which materials or services are provided under such contracts. The Company estimates clinical trial and research agreement related expenses based on the services performed, pursuant to contracts with research institutions and clinical research organizations and other vendors that conduct clinical trials and research on the Company’s behalf. In accruing clinical and research related fees, the Company estimates the time period over which services will be performed and activity expended in each period. If the actual timing of the performance of services or the level of effort varies from the estimate, the Company will adjust the accrual accordingly. Payments made to third parties under these arrangements in advance of the receipt of the related services are recorded as prepaid expenses until the services are rendered. Stock Repurchases In November 2015, the board of directors approved a share repurchase program (2015 Share Repurchase Program) allowing the CEO or CFO, on behalf of the Company, to repurchase from time to time, in the open market or in privately negotiated transactions, up to $50.0 million of the Company’s outstanding shares of common stock, exclusive of any commissions, markups or expenses. The timing and amounts of any purchases will be based on market conditions and other factors, including price, regulatory requirements and other corporate considerations. The 2015 Share Repurchase Program does not require the purchase of any minimum number of shares and may be suspended, modified or discontinued at any time without prior notice. The Company expects to finance the purchases with existing cash balances. As it is the intent for the repurchased shares to be retired, the Company has elected to account for the shares repurchased under the constructive retirement method. For shares repurchased in excess of par, the Company will allocate the excess value to accumulated deficit. Stock-Based Compensation In the second quarter of 2016, the Company implemented Financial Accounting Standards Board (FASB) Accounting Standard Update (ASU) 2016-09, Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting Use of Estimates The preparation of condensed consolidated financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make certain estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the condensed consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. On an ongoing basis, the Company evaluates its estimates, including those related to the valuation of warrants, stock-based compensation, the valuation allowance for deferred tax assets, preclinical and clinical trial accruals, and the valuation of build-to-suit lease assets. The Company bases its estimates on historical experience and on various other market-specific and relevant assumptions that it believes to be reasonable under the circumstances. Actual results could differ from those estimates. Basic and Diluted Net Loss per Share of Common Stock Basic net loss per share is calculated by dividing the net loss by the weighted-average number of common shares outstanding for the period. Diluted loss per share is computed similarly to basic loss per share except that the denominator is increased to include the number of additional shares that would have been outstanding if the potential common shares had been issued and if the additional common shares were dilutive. For all periods presented, potentially dilutive securities are excluded from the computation of fully diluted loss per share as their effect is anti-dilutive. The following table details those securities that have been excluded from the computation of potentially dilutive securities: As of September 30, 2016 2015 Outstanding options 6,518,062 9,811,356 Outstanding restricted stock units 859,022 485,150 Outstanding warrants 17,775,257 17,824,525 Total 25,152,341 28,121,031 Amounts in the table above reflect the common stock equivalents of the noted instruments. Recent Accounting Pronouncements In February 2016, the FASB issued or ASU 2016-02, Leases (Topic 842) In March 2016, the FASB issued ASU 2016-09, Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting The Company has adopted the guidance to 1) account for stock-based award forfeitures as they occur rather than apply an estimated forfeiture rate, 2) recognize the income tax effects of awards in the income statement when the awards vest or are settled, thus eliminating additional paid-in capital pools, 3) repurchase more of an employee’s shares for tax withholding purposes without triggering liability accounting, and 4) elected to adopt the amendments related to the presentation of excess tax benefits on the statement of cash flows using a prospective transition method. In June 2016, the FASB issued ASU 2016-13, Financial Instruments – Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments. In August 2016, the FASB issued ASU 2016-15, Statement of Cash Flows (Topic 230) ASU 2016-15 is effective for annual reporting periods, including interim periods within those annual periods, beginning after December 15, 2017, with early adoption permitted. Entities are required to use a retrospective transition approach for all of the issues identified to each period presented. The Company is currently evaluating the impact that the adoption of ASU 2016-15 will have on the Company’s consolidated financial statements and disclosures.

Financial Statement Details

Financial Statement Details	9 Months Ended
	Sep. 30, 2016
Financial Statement Details [Abstract]
Financial Statement Details	3. Financial Statement Details Prepaid Expenses and Other Current Assets As of September 30, 2016 and December 31, 2015, prepaid expenses and other current assets consisted of (in thousands): September 30, 2016 December 31, 2015 (Unaudited) Prepaid services $ 1,866 $ 631 Interest receivable - marketable securities 1,185 911 Prepaid insurance 737 466 Prepaid license fees 462 101 Prepaid legal fees 350 350 Prepaid rent 287 — Due from related parties (Note 8) 76 217 Tax refund receivable — 646 Other 252 — $ 5,215 $ 3,322 Property and Equipment, Net As of September 30, 2016 and December 31, 2015, property and equipment consisted of (in thousands): September 30, 2016 December 31, 2015 (Unaudited) Construction in progress $ 5,864 $ 5,136 Building under build-to-suit lease 4,348 — Equipment 3,798 241 Leasehold improvements 2,413 182 Software 458 6 Furniture & fixtures 190 125 17,071 5,690 Accumulated depreciation (596 ) (167 ) $ 16,475 $ 5,523 Building value of $4.3 million under a build-to-suit lease represents the estimated fair market value of a building which the Company is the “deemed owner” for accounting purposes only and related non-normal tenant improvements. See Note 6 – Financing Lease Obligation Construction in progress as of September 30, 2016 includes the estimated fair value of the Company’s build-to-suit lease related to its facility in El Segundo, California for $5.1 million of which the Company is the “deemed owner” for accounting purposes only. See Note 6 – Build-to-suit Lease Intangible Assets As of September 30, 2016 and December 31, 2015, intangible assets consisted of (in thousands): September 30, 2016 December 31, 2015 (Unaudited) Technology license* $ 8,636 $ 8,636 Less accumulated amortization (2,688 ) (1,344 ) $ 5,948 $ 7,292 *Inclusive of $1.5 million intangible asset related to the deferred tax liability, which is not amortized. Amortization expense was $0.4 million and $0.4 million for the three months ended September 30, 2016 and 2015, respectively, and $1.3 million and $0.8 million for the nine months ended September 30, 2016 and 2015, respectively. Amortization for the Company’s technology license is included in research and development expense in the condensed consolidated statement of operations. Other Assets As of September 30, 2016 and December 31, 2015, other assets consisted of (in thousands): September 30, 2016 December 31, 2015 (Unaudited) Equipment not placed in service $ 533 $ 624 License fees 192 — Security deposit 137 344 Software license and implementation costs — 391 $ 862 $ 1,359 Accrued Expenses As of September 30, 2016 and December 31, 2015, accrued expenses consisted of (in thousands): September 30, 2016 December 31, 2015 (Unaudited) Accrued bonus $ 1,622 $ 1,359 Accrued professional and service fees 1,469 367 Accrued construction costs 990 132 Accrued preclinical and clinical trial costs 866 — Accrued compensation 814 348 Accrued franchise and property taxes 14 225 Other 135 144 $ 5,910 $ 2,575 Investment Income, Net Net investment income includes interest income from all bank accounts as well as marketable securities, net realized gains or losses on sales of investments and the amortization of the premiums and discounts of the investments and is as follows for the three and nine months ended September 30, 2016 and 2015 (in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2016 2015 2016 2015 Interest income $ 1,371 $ 81 $ 3,802 $ 146 Investment amortization accretion expense, net (625 ) — (1,567 ) — Net realized gains on investments 49 — 67 — $ 795 $ 81 $ 2,302 $ 146 Interest income includes interest from the Company’s bank deposits. The Company did not recognize an impairment loss on any investments for the three and nine months ended September 30, 2016 and 2015.

Cash Equivalents and Marketable

Cash Equivalents and Marketable Securities	9 Months Ended
	Sep. 30, 2016
Cash Equivalents And Marketable Securities [Abstract]
Cash Equivalents and Marketable Securities	4. Cash Equivalents and Marketable Securities As of September 30, 2016, all of the Company’s marketable securities are classified as available-for-sale and are scheduled to mature within 5.0 years. At September 30, 2016, the detail of the Company’s cash equivalents and marketable securities is as follows (in thousands): September 30, 2016 Amortized Cost Unrealized Unrealized Losses Fair Value Current: Commercial paper $ 16,476 $ — $ — $ 16,476 Government sponsored securities 26,292 32 (1 ) 26,323 Corporate debt securities 147,528 42 (49 ) 147,521 Foreign government bonds 4,005 3 — 4,008 Current portion 194,301 77 (50 ) 194,328 Noncurrent: Government sponsored securities 22,022 83 — 22,105 Corporate debt securities 70,931 270 (54 ) 71,147 Foreign government bonds 1,405 — (2 ) 1,403 Noncurrent portion 94,358 353 (56 ) 94,655 Total $ 288,659 $ 430 $ (106 ) $ 288,983 The cash equivalent portion included in the current fair values above is $16.5 million in commercial paper. At September 30, 2016, 47 of the securities and bonds are in an unrealized loss position. No securities have been in an unrealized loss position for greater than 12 months. Available-for-sale investments that had been in an unrealized loss position for less than 12 months at September 30, 2016 are as follows (in thousands): September 30, 2016 Estimated Fair Value Gross Unrealized Losses Government sponsored securities $ 5,010 $ (1 ) Corporate debt securities 96,052 (103 ) Foreign government bonds 1,403 (2 ) Total $ 102,465 $ (106 ) The Company evaluated its securities for other-than-temporary impairment and concluded that the decline in value was primarily caused by current economic and market conditions. The Company does not intend to sell the investments and it is not more likely than not that the Company will be required to sell the investments before recovery of their amortized cost bases. Therefore, the Company did not recognize any other-than-temporary impairment loss during the three and nine months ended September 30, 2016 and 2015.

Fair Value Measurements

Fair Value Measurements	9 Months Ended
	Sep. 30, 2016
Fair Value Disclosures [Abstract]
Fair Value Measurements	5. Fair Value Measurements In accordance with the authoritative guidance for financial assets and liabilities measured at fair value on a recurring basis (ASC Topic 820), the Company prioritizes the inputs used to measure fair value from market-based assumptions to entity specific assumptions as follows: • Level 1—Inputs based on quoted market prices for identical assets or liabilities in active markets at the measurement date. • Level 2—Observable inputs other than quoted prices in Level 1, such as quoted prices for similar assets and liabilities in active markets; quoted prices for identical or similar assets and liabilities in markets that are not active; or other inputs that are observable or can be corroborated by observable market data. • Level 3—Inputs which reflect management’s best estimate of what market participants would use in pricing the asset or liability at the measurement date. The inputs are unobservable in the market and significant to the instruments valuation. The following table presents the Company’s hierarchy for its assets measured at fair value on a recurring basis as of September 30, 2016 and December 31, 2015: Fair Value Measurements at September 30, 2016 Total Level 1 Level 2 Level 3 Assets: Current: Cash and cash equivalents* $ 16,476 $ — $ 16,476 $ — Government sponsored securities 26,323 — 26,323 — Corporate debt securities 147,521 — 147,521 — Foreign government bonds 4,008 — 4,008 — Noncurrent: Government sponsored securities 22,105 — 22,105 — Corporate debt securities 71,147 — 71,147 — Foreign government bonds 1,403 — 1,403 — Total assets measured at fair value $ 288,983 $ — $ 288,983 $ — *This amount excludes $14.9 million in depository institutions that are classified as Level 1 assets. Fair Value Measurements at December 31, 2015 Total Level 1 Level 2 Level 3 Assets: Current: Cash and cash equivalents* $ 18,039 $ — $ 18,039 $ — Commercial paper 24,917 — 24,917 — Corporate debt securities 86,450 — 86,450 — Foreign government bonds 6,943 — 6,943 — Noncurrent: Corporate debt securities 51,131 — 51,131 — Foreign government bonds 4,004 — 4,004 — Total assets measured at fair value $ 191,484 $ — $ 191,484 $ — *This amount excludes $157.9 million in depository institutions which are classified as Level 1 assets.

Commitment and Contingencies

Commitment and Contingencies	9 Months Ended
	Sep. 30, 2016
Commitments And Contingencies Disclosure [Abstract]
Commitments and contingencies	6. Commitments and Contingencies Collaborative Arrangement A collaborative arrangement is a contractual arrangement that involves a joint operating activity. These arrangements involve two or more parties who are (i) active participants in the activity, and (ii) exposed to significant risks and rewards dependent on the commercial success of the activity. Exclusive Co-Development Agreement —In August 2016, the Company entered into an exclusive Co-Development Agreement (the Co-Development Agreement) with Altor BioScience Corporation (Altor). Under the Co-Development Agreement, the Company and Altor agreed to exclusively collaborate on the development of therapeutic applications combining the Company’s proprietary natural killer cells with Altor's ALT-801 and/or ALT-803 products with respect to certain technologies and intellectual property rights as may be agreed between the parties for the purpose of jointly developing therapeutic applications of certain effector cell lines. The Company will be the lead developer for each product developed by the parties pursuant to the Co-Development Agreement unless otherwise agreed to under a given project plan. Under the terms of the Co-Development Agreement, both parties grant a co-exclusive, royalty free, fully paid-up, worldwide license, with the right to sublicense (only to a third-party contractor assisting with research and development activities under this Co-Development Agreement and subject to prior consent, not to be unreasonably withheld), under the intellectual property (IP), including the parties interest in the joint IP, solely to conduct any development activities agreed to by the steering committee as set forth in any development plan. Unless otherwise mutually agreed by the parties in the development plan for a project, the Company shall be responsible for all costs and expenses incurred by either party related to conducting clinical trials and other activities under each development program, including costs associated with patient enrollment, materials and supplies, third-party staffing and regulatory filings. Altor and the Company each will own an undivided interest in and to all rights, title and interest in and to the joint product rights. The Co-Development Agreement expires upon the fifth anniversary of the effective date. There was no joint research activity under the Co-Development Agreement during three months ended September 30, 2016. Contingencies The Company records accruals for loss contingencies to the extent that the Company concludes it is probable that a liability has been incurred and the amount of the related loss can be reasonably estimated. The Company evaluates, on a quarterly basis, developments in legal proceedings and other matters that could cause a change in the potential amount of the liability recorded or of the range of potential losses disclosed. In March 2009, the Company received a final rejection in one of the Company’s original patent applications pertaining to certain limited methods of use claims for NK-92 from the U.S. Patent and Trademark Office (the USPTO) (but the USPTO allowed claims on all of the other proposed claims, including other methods of use). The Company appealed this decision with the USPTO Board of Appeals and, in the fall of 2013, the Board of Appeals reversed the Examiner’s rejection of the claim to certain limited methods of use with NK-92, but affirmed the Examiner’s rejection of the remaining patent claims. In December 2013, the Company brought an action in the U.S. District Court for the Eastern District of Virginia to review the decision of the USPTO as the Company disagreed with the decision as to the certain limited non-allowed claims. On September 2, 2015, the U.S. District Court granted the USPTO’s motion for summary judgment. The Company is in the process of appealing the decision. Based on the information available at present, the Company cannot reasonably estimate a range of loss for this action. Accordingly, no liability associated with this action has been accrued. The Company is expensing legal costs associated with defending this litigation as the costs are incurred. Securities Litigation In March 2016, a securities class action complaint captioned Sudunagunta v. NantKwest, Inc., et al. Forsythe v. NantKwest, Inc., et al. In May 2016, the first of several complaints was filed in California Superior Court, Los Angeles County also related to the Company’s restatement of certain interim financial statements. Those complaints are captioned Wagner v. NantKwest, Inc., et al. Frye v. NantKwest, Inc., et al. Hare v. NantKwest, Inc. Wiencek v. NantKwest, Inc. et al. Sudunagunta Forsythe On September 6, 2016, a shareholder derivative complaint captioned Bushansky v. Soon-Shiong, et al. Contractual Obligations - Leases The Company leases: (i) office space in Cardiff-by-the-Sea, California; (ii) a research facility in Woburn, Massachusetts; (iii) office space in Cary, North Carolina; (iv) a research facility in San Diego, California; (v) research and manufacturing space in Culver City, California from a related party (Note 7) and; (vi) a research and manufacturing facility in El Segundo, California, also from a related party (Note 7). The Company recognizes rent expense under its operating leases on a straight-line basis. Rent expense for the three months ended September 30, 2016 and 2015 was $0.8 million and $0.7 million, respectively, and $2.2 million and $0.8 million for the nine months ended September 30, 2016 and 2015, respectively. Build-to-suit Lease In September 2016, the Company entered into a lease agreement with 605 Doug St, LLC, a related party (Note 7), for approximately 24,250 square feet in El Segundo, California, which is to be converted to a research and development laboratory and a Good Manufacturing Practices (GMP) laboratory. The lease runs from July 2016 through July 2023. The Company has the option to extend the lease for an additional three year term through July 2026. The monthly rent is $0.1 million with annual increases of 3% beginning in July 2017. For the three months ended September 30, 2016, the Company recorded rent expense of $0.1 million, which is reflected in research and development expense on the condensed consolidated statement of operations. The Company is responsible for costs to build out the laboratory and has incurred costs of approximately $0.7 million as of September 30, 2016, which is reflected in construction in progress on the condensed consolidated balance sheet. Additionally, in order for the facility to meet the Company's research and development and GMP laboratory specifications, the Company started to make certain structural changes to the facility as part of the conversion to laboratory space. As a result of these changes, the Company concluded that it is the “deemed owner” of the building (for accounting purposes only) during the construction period. Accordingly, the Company recorded a non-cash build-to-suit lease asset of $5.1 million, representing its estimate of the fair market value of the building, and a corresponding construction build-to-suit lease liability, recorded as a component of other current and non-current liabilities on the condensed consolidated balance sheet as of September 30, 2016. Upon completion of construction of this facility, the Company evaluates the de-recognition of the asset and liability under the provisions of ASC 840-40 Leases - Sale-Leaseback Transactions Financing Lease Obligation Under a November 2015 facility license agreement with NantWorks for office and laboratory space, which was effective May 22, 2015, the Company is responsible for costs to build out the laboratory and has incurred costs of approximately $3.5 million as of September 30, 2016. The Company concluded that it was the “deemed owner” of the building (for accounting purposes only) during the construction period. The Company recorded the build out costs as an asset with a corresponding build-to-suit liability, which was recorded as a component of other current and non-current liabilities on the condensed consolidated balance sheet while the building was under construction. Upon completion of construction of this building in August 2016, the Company evaluated the de-recognition of the asset and liability under the provisions of ASC 840-40 Leases – Sale-Leaseback Transactions. Commitments The Company has not entered into any new significant contracts during the three months ended September 30, 2016 other than the above mentioned lease agreement.

Related Party Agreements

Related Party Agreements	9 Months Ended
	Sep. 30, 2016
Related Party Transactions [Abstract]
Related Party Agreements	7. Related Party Agreements The Company’s Chairman and CEO founded and has a controlling interest in NantWorks, which is a collection of multiple companies in the healthcare and technology space. As described below, the Company has entered into arrangements with NantWorks and certain affiliates of NantWorks to facilitate the development of new genetically modified NK cells for the Company’s product pipeline. In September 2016, the Company entered into a lease agreement with 605 Doug St, LLC, an entity owned by the Company’s Chairman and CEO, for approximately 24,250 square feet in El Segundo, California, which is to be converted to a research and development laboratory and a Good Manufacturing Practices (GMP) laboratory. The lease runs from July 2016 through July 2023. The Company has the option to extend the lease for an additional three year term through July 2026. The monthly rent is $0.1 million with annual increases of 3% beginning in July 2017. See Note 6 - Commitments and Contingencies In August 2016, the Company entered into a Co-Development Agreement with Altor as described in Note 6, Commitments and Contingencies. The Company’s Chairman and CEO is also the Chairman of Altor and holds a greater than 20% ownership interest in Altor. Through September 30, 2016, the Company has not conducted any joint operating activities or incurred any costs under this Co-Development Agreement. In March 2016, NantBioScience, Inc. (NantBioScience), a NantWorks company, and the National Cancer Institute entered into a cooperative research and development agreement. The agreement covers NantBioScience and its affiliates, including the Company. Under the agreement, the parties will collaborate on the preclinical and clinical development of proprietary recombinant NK cells and monoclonal antibodies in monotherapy and in combination immunotherapies. The Company expects to benefit from the preclinical and clinical research conducted during the first year under this agreement and is providing the first year of funding under the five-year agreement. In April 2016, the Company paid $0.6 million to the National Cancer Institute as a prepayment for this first year of funding. The Company recognizes research and development expense ratably over a 12-month period and recorded $0.3 million as of September 30, 2016. Under the NantWorks shared services agreement executed in November 2015, but effective August 2015, NantWorks provides corporate, general and administrative, manufacturing strategy, research and development, regulatory and clinical trial strategy and other support services, and the Company is charged for the services at cost plus reasonable allocations for indirect costs that relate to the employees providing the services. For the three months ended September 30, 2016 and 2015, the Company recorded $0.8 million and $0.3 million, respectively, to selling, general and administrative expense and $2.3 million and $0.3 million, respectively, for the nine months ended September 30, 2016 and 2015. For the three months ended September 30, 2016 and 2015, the Company recorded $0.4 million and $0.1 million, respectively, in research and development expense under this arrangement on the condensed consolidated statement of operations, and $1.2 million and $0.1 million for the nine months ended September 30, 2016 and 2015. In June 2016, the Company amended the existing shared services agreement with NantWorks whereby the Company can provide such support services to NantWorks and/or any of its affiliates. For the three and nine months ended September 30, 2016, the Company recorded expense reimbursements of $17,000 and $26,000, respectively, to selling, general and administrative expense and $0.1 million and $0.1 million, respectively, to research and development expense. The Company owed NantWorks a net amount of $1.7 million for all agreements between the two affiliates at September 30, 2016, which is included in due to related parties on the condensed consolidated balance sheet. Under the November 2015 facility license agreement with NantWorks for office and laboratory space, which was effective May 22, 2015, the Company recorded rent expense of $0.1 million and $0.1 million for the three months ended September 30, 2016 and 2015, respectively, and $0.3 million and $0.1 million for the nine months ended September 30, 2016 and 2015, which is included in research and development expense on the condensed consolidated statement of operations. The Company is responsible for costs to build out the laboratory and has incurred costs of approximately $3.5 million as of September 30, 2016, which is reflected in property and equipment, net, on the condensed consolidated balance sheet. See Note 6 - Commitments and Contingencies Under the June 2015 agreement with NantOmics, LLC (NantOmics) to obtain genomic sequencing and proteomic analysis services, as well as related data management and bioinformatics services, exclusively from NantOmics, the Company incurred $0.1 million and $0.2 million of cost in the three and nine months ended September 30, 2016, respectively, which is included in research and development expense on the condensed consolidated statement of operations. No expense was incurred in the three and nine months ended September 30, 2015. The Company is obligated to pay NantOmics a fixed, per sample fee, determined based on the type of services being provided. The agreement has an initial term of five years and renews automatically for successive one year periods, unless terminated earlier. The Company owed NantOmics a net amount of $0.1 million at September 30, 2016, which is included in due to related parties on the condensed consolidated balance sheet.

Spinout of Brink Biologics and

Spinout of Brink Biologics and Coneksis	9 Months Ended
	Sep. 30, 2016
Spinout
Spinout of Brink Biologics and Coneksis	8. Spinout of Brink Biologics and Coneksis On June 9, 2015, the Company spun out its business related to testing and diagnostic products and services into the entity, Brink Biologics, Inc. (Brink Biologics) in exchange for all of the issued and outstanding shares of Brink Biologics which were subsequently distributed by a dividend to the Company’s stockholders. Under the spin-out arrangement, the Company transferred to Brink Biologics all of the Company’s existing revenue-earning, non-exclusive license agreements that allow third parties to use the Company’s cell lines and intellectual property for non-clinical laboratory testing. In addition, the Company transferred or licensed to Brink Biologics the Company’s other assets associated with testing and diagnostics products and services. The Company granted to Brink Biologics worldwide, exclusive licenses to the use of certain cell lines limited to the field of in vitro in vivo On June 9, 2015, the Company spun out its business related to veterinary oncology into the entity, Coneksis in exchange for all of the issued and outstanding shares of Coneksis which were subsequently distributed by a dividend to our stockholders. In connection with the spin-out arrangement, the Company granted to Coneksis worldwide, exclusive licenses for use of certain cell lines in the field of veterinary medical research and therapeutics, trademarks, intellectual property, and patents, including the Company’s rights under its license agreement with Fox Chase Cancer Center. As part of the agreement, the Company also has a non-exclusive license to any results and data arising from Coneksis’ use of the Company’s cell lines and intellectual property for the Company’s use for internal research purposes and outside of Coneksis’ field. In consideration for the license grants, Coneksis is obligated to pay the Company a single-digit royalty on amounts received for the sale of licensed products and services, as well as a single-digit percentage share of other revenue received by Coneksis from the grant of sublicenses under the Company’s rights. Coneksis and the Company have the right to terminate the license agreement under certain conditions. Also, as part of the spin-out arrangement, the Company has agreed to provide certain services to Coneksis for a transitional period on a fee-for-service basis. The Company recorded $6,000 and $3,000, respectively, for the three months ended September 30, 2016 and 2015 and $9,000 and $3,000, respectively, for the nine months ended September 30, 2016 and 2015, for services provided to Coneksis, which is included in other income on the condensed consolidated statement of operations. At September 30, 2016, Coneksis owes the Company $15,000, which has been fully reserved. The Company determined it has a variable interest in Brink Biologics and Coneksis through its royalty agreements. Based upon the level of equity investment at risk, Brink Biologics and Coneksis are considered variable interest entities (VIEs). The Company considered whether it is the primary beneficiary of the Brink Biologics and Coneksis VIEs and required to consolidate the entities. As the Company does not control the research and development or the sales of the potential licensed or commercialized products, the Company does not direct the activities of Brink Biologics and Coneksis that most significantly impact their economic performance. Therefore, the Company determined that it is not the primary beneficiary of the entities and does not consolidate the Brink Biologics VIE and the Coneksis VIE.

Stockholders' Equity

Stockholders' Equity	9 Months Ended
	Sep. 30, 2016
Equity [Abstract]
Stockholders' Equity	9. Stockholders’ Equity Stock Repurchase— In November 2015, the board of directors approved a share repurchase program (2015 Share Repurchase Program) allowing the CEO or CFO, on behalf of the Company, to repurchase from time to time, in the open market or in privately negotiated transactions, up to $50.0 million of the Company’s outstanding shares of common stock, exclusive of any commissions, markups or expenses. The timing and amounts of any purchases will be based on market conditions and other factors, including price, regulatory requirements and other corporate considerations. The 2015 Share Repurchase Program does not require the purchase of any minimum number of shares and may be suspended, modified or discontinued at any time without prior notice. The Company expects to finance the purchases with existing cash balances. During the three and nine months ended September 30, 2016, the Company repurchased 365,440 and 1,594,040 shares of its common stock, respectively, at prices ranging between $6.05 per share and $8.50 per share for a total of $11.9 million. The shares are formally retired through board approval upon repurchase. The Company incurred approximately $28,000 of broker commissions on the repurchases. The Company accounted for the repurchases under the constructive retirement method and allocated the excess of the repurchase price over par value to accumulated deficit. At September 30, 2016, $38.1 million remained authorized for repurchase under the Company’s 2015 Share Repurchase Program. A summary of common stock repurchases for the nine months ended September 30, 2016 is as follows: Total number of shares purchased Average price paid per share Total number of shares purchased as part of publicly announced plans or programs Maximum approximate dollar value of shares that may yet be purchased under the plans or programs February 300,000 $ 8.50 300,000 $47.5 million May 346,200 $ 6.77 646,200 $45.1 million June 582,400 $ 7.56 1,228,600 $40.7 million August 335,440 $ 7.01 1,564,040 $38.4 million September 30,000 $ 7.40 1,594,040 $38.1 million Total 1,594,040 $ 7.45

Stock-Based Compensation

Stock-Based Compensation	9 Months Ended
	Sep. 30, 2016
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock-Based Compensation	10. Stock-Based Compensation Stock-Based Compensation The following table presents stock-based compensation included on the Company’s condensed consolidated statements of operations (in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2016 2015 2016 2015 (Restated) (Restated) Stock-based compensation expense: Warrants for Class A common stock to an officer $ 14,171 $ 7,636 $ 41,443 $ 129,811 Warrants for Class A common stock to an officer and a director related to Inex Bio, Inc. acquisition — — — 22,747 Employee stock options 3,075 16,424 12,826 20,033 Non-employee stock options — 784 — 3,074 Employee restricted stock units 1,321 14,150 7,851 14,150 Non-employee restricted stock units 102 — 466 — $ 18,669 $ 38,994 $ 62,586 $ 189,815 Stock-based compensation expense in operating expenses: Research and development $ 116 $ 364 $ 680 $ 1,140 Selling, general and administrative 18,553 38,630 61,906 188,675 $ 18,669 $ 38,994 $ 62,586 $ 189,815 In the second quarter of 2016, the Company adopted ASU 2016-09, Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting ASU 2016-09 also requires the recognition of the income tax effects of awards in the condensed consolidated statement of operations when the awards vest or are settled, thus eliminating addition paid-in capital pools. The Company elected to adopt the amendments related to the presentation of excess tax benefits on the condensed consolidated statement of cash flows using a prospective transition method. Stock Options The following table summarizes stock option activity under the equity incentive plans for the nine months ended September 30, 2016 (in thousands, except for share and per share amounts): Number of Shares Weighted- Average Exercise Aggregate Intrinsic Value Weighted- Average Remaining Contractual (in years) Outstanding at December 31, 2015 8,777,893 $ 5.36 $ 116,273 7.2 Options forfeited (71,627 ) $ 2.00 Options exercised (2,188,204 ) $ 0.67 Outstanding at September 30, 2016 6,518,062 $ 6.97 $ 30,364 6.7 Vested and Exercisable at September 30, 2016 5,041,877 The aggregate intrinsic value of stock options exercised during the nine months ended September 30, 2016 was $15.8 million. The total unrecognized compensation cost related to non-vested stock options as of September 30, 2016 is $11.0 million, which is expected to be recognized over a weighted-average period of 2.2 years. Restricted Stock Units The following table summarizes the activity for restricted stock units under the 2015 Plan: Number of Restricted Stock Units Outstanding Weighted-Average Grant Date Fair Value Unvested balance at December 31, 2015 1,129,638 $ 20.51 Granted 407,800 $ 7.76 Vested (514,316 ) $ 24.13 Forfeited (164,100 ) $ 12.10 Unvested balance at September 30, 2016 859,022 $ 13.90 During the nine months ended September 30, 2016, the Company granted restricted stock units of 407,800 shares of common stock, of which 340,300 were granted to employees of the Company and 67,500 were granted to employees of related companies under the Company’s shared services agreement with NantWorks (Note 7). As of September 30, 2016, there was $6.9 million of unrecognized stock-based compensation expense related to restricted stock units that is expected to be recognized over a weighted-average period of 3.2 years. Of that amount, $4.3 million of unrecognized expense is related to employee grants with a weighted-average period of 3.2 year and $2.6 million of unrecognized expense is related to non-employee grants with a weighted-average period of 3.1 years and is impacted by periodic mark-to-market adjustments. Warrants The following table summarizes the warrant activity for the nine months ended September 30, 2016: Outstanding at December 31, 2015 17,819,616 Warrants exercised (40,514 ) Warrants forfeited (3,845 ) Outstanding at September 30, 2016 17,775,257 Vested and exercisable at September 30, 2016 12,035,607 The total unrecognized compensation cost related to non-vested warrants as of September 30, 2016 is $58.5 million, which is expected to be recognized over a weighted-average period of 1.8 years.

Acquisition of Inex Bio, Inc

Acquisition of Inex Bio, Inc	9 Months Ended
	Sep. 30, 2016
Business Combinations [Abstract]
Acquisition of Inex Bio, Inc	11. Acquisition of Inex Bio, Inc. In April 2012, the Company made a strategic decision to enter into a License Agreement with Inex Bio, Inc. (Inex Bio), a Republic of Korea corporation (the Inex License Agreement). Under the Inex License Agreement, the Company provided Inex Bio with an exclusive license to the Company’s technology to be used in products only in certain Asian countries. In exchange for the Inex License Agreement, the Company received a $0.3 million up-front license fee. In addition, the Company was eligible to receive milestone payments of up to $0.8 million based upon completion of clinical trials and a 5% royalty on net sales of applicable products using the aNK cells. No milestone payments were due or received for the three months ended March 31, 2015, the quarter in which the Company completed its acquisition of Inex Bio, as further discussed below. In May 2012, the Company acquired 57,000 shares of Inex Bio for $0.2 million, which represented 22.2% of the outstanding shares and 17.4% of the fully-diluted shares of Inex Bio. The Company accounted for its investment under the equity method. The Company reviewed its investment for impairment in accordance with ASC Topic 320, Investments—Debt and Equity Securities. In February and March 2015, InexBio Holdings, LLC (Holdings), an entity owned 50% by Cambridge Equities, L.P., an entity in which the Company’s CEO is the sole member of its general partner, and 50% by Eragon Ventures, LLC, an entity of which one of the Company’s former directors is managing member, acquired 220,000 shares or 67.3% of Inex Bio from third party owners for $1.1 million. On March 30, 2015, the Company entered into a Stock Purchase Agreement with Holdings and the third party owners, pursuant to which the Company acquired all the remaining outstanding shares of Inex Bio not previously held by the Company. The Company paid to the other owners of Inex Bio cash of $1.5 million and issued warrants to acquire 593,072 shares of the Company’s Class A common stock at an exercise price of $2.00 per share. The Company valued the warrants using the Black-Sholes option-pricing model with a stock price of $10.72 per share as of March 30, 2015, an expected term of 0.04 years, and a volatility of 80%. This resulted in a total fair value of the warrants of $5.2 million. In April 2015, the Company received $1.2 million for the full exercise of the warrants. The Company recorded the transaction as an asset purchase because Inex Bio was a shell corporation without any employees or other significant assets and it did not meet the definition of a business under ASC Topic 805, Business Combinations The purchase price paid to acquire Inex Bio from the other owners is as follows (in thousands): Consideration Total Cash paid by InexBio Holdings, LLC $ 1,100 Cash paid by Company 1,482 Fair value of warrants 5,170 Aggregate purchase price $ 7,752 The following table summarizes the assets acquired and liabilities assumed (in thousands): Cash $ 763 Intangible assets—reacquired rights of Company technology* 8,636 Other assets 42 Investment in Inex Bio (221 ) Deferred tax liability (1,467 ) Accounts payable (1 ) Total assets acquired and liabilities assumed $ 7,752 * Inclusive of $1.5 million intangible asset related to deferred tax liability. The license solely covers pending patent applications at the time of purchase. The Company amortizes the intangible assets over 4 years, which represents the period until the next action date of the pending patent application in the territory of the license issued to Inex Bio. The Company paid Holdings cash of $6.5 million and issued warrants to acquire 2,609,520 shares of the Company’s Class A common stock at an exercise price of $2.00 per share for its assistance in negotiating the acquisition of Inex Bio from the other owners. The Company valued the warrants using the Black-Sholes option-pricing model with a stock price of $10.72 per share as of March 30, 2015, an expected term of 0.04 years, and a volatility of 80%. This resulted in a fair value of total warrants of $22.7 million. In April 2015, the Company received $5.2 million for the full exercise of the warrants. The following summarizes the net consideration paid to Holdings (in thousands): Consideration Total Cash $ 6,518 Fair value of warrants 22,747 Less cash paid to acquire shares in Inex Bio (1,100 ) Net consideration $ 28,165 The Company recorded compensation expense for the portion of the cash and warrants issued to Holdings that exceeded the fair value of the shares acquired consistent with ASC Topic 718. The Company recorded $22.7 million of stock-based compensation and $5.4 million of cash compensation to the Company’s chief executive officer and the former director as a result of acquiring their interest in Inex Bio.

Income Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2016
Income Tax Disclosure [Abstract]
Income Taxes	12. Income Taxes The difference between the federal statutory tax rate of 34% and the Company’s 0% tax rate is due to losses in jurisdictions from which the Company cannot benefit. Intraperiod tax allocation rules require the Company to allocate the provision for income taxes between continuing operations and other categories of earnings, such as other comprehensive income. In periods in which the Company has a year-to-date pre-tax loss from continuing operations and pre-tax income in other categories of earnings, such as other comprehensive income, the Company must allocate the tax provision to the other categories of earnings. The Company then records a related tax benefit in continuing operations. During the nine months ended September 30, 2016, the Company recorded unrealized gains on its marketable securities in other comprehensive income, net of taxes. As a result, for the nine months ended September 30, 2016 and 2015, the Company recorded a $0.1 million and $0 tax benefit, respectively, on the condensed consolidated statement of operations and $0.2 million and $0, respectively, in other comprehensive income. The Company is operating in Korea. During the nine months ended September 30, 2016 and 2015, the tax benefit related to Korea is $0.3 million and $0, respectively. The Company currently files federal and state income tax returns in the United States and in Korea. Income tax expense consists of U.S. federal, state, and Korean income taxes. To date, the Company has not been required to pay U.S. federal income taxes because of current and accumulated net operating losses. Under ASU 2016-09, all excess tax benefits and tax deficiencies (including tax benefits of dividends on share-based payment awards) should be recognized as income tax expense or benefit in the statement of operations. The tax effects of exercised or vested awards should be treated as discrete items in the reporting period in which they occur. An entity also should recognize excess tax benefits regardless of whether the benefits reduce tax payable in the current period. The Company made an early adoption on the ASU 2016-09 effect in the second quarter of 2016. There is no cumulative impact as the federal excess deduction recognition of $40,000 and the state excess deduction recognition of $34,000 are offset by a corresponding change to the valuation allowance. The current year excess benefit of $6.4 million is offset by a corresponding change in the valuation allowance.

Summary of Significant Accoun20

Summary of Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2016
Accounting Policies [Abstract]
Principles of Consolidation	Principles of Consolidation The Company’s condensed consolidated financial statements include the accounts of the Company and its wholly-owned subsidiary, Inex Bio, Inc., and have been prepared in accordance with GAAP. All intercompany amounts have been eliminated.
Liquidity	Liquidity As of September 30, 2016, the Company had an accumulated deficit of approximately $358.9 million. The Company also had negative cash flow from operations of approximately $27.8 million during the nine months ended September 30, 2016. The Company expects that it will likely need additional capital to further fund development of, and seek regulatory approvals for, its product candidates, and begin to commercialize any approved products. The Company is currently focused primarily on the development of immunotherapeutic treatments for cancers and debilitating viral infections using targeted cancer killing cell lines, and believes such activities will result in the Company’s continued incurrence of significant research and development and other expenses related to those programs. If the clinical trials for any of the Company’s product candidates fail or produce unsuccessful results and those product candidates do not gain regulatory approval, or if any of the Company’s product candidates, if approved, fails to achieve market acceptance, the Company may never become profitable. Even if the Company achieves profitability in the future, it may not be able to sustain profitability in subsequent periods. The Company intends to cover its future operating expenses through cash and cash equivalents and marketable securities on hand and through a combination of equity offerings, debt financings, government or other third-party funding, marketing and distribution arrangements and other collaborations, strategic alliances and licensing arrangements. Additional financing may not be available to the Company when needed and, if available, financing may not be obtained on terms favorable to the Company or its stockholders. While the Company expects its existing cash and cash equivalents and marketable securities will enable it to fund operations and capital expenditure requirements for the foreseeable future, it may not have sufficient funds to reach commercialization. Failure to obtain adequate financing when needed may require the Company to delay, reduce, limit or terminate some or all of its development programs or future commercialization efforts or grant rights to develop and market product candidates that the Company might otherwise prefer to develop and market itself which could adversely affect the Company’s ability to operate as a going concern. If the Company raises additional funds from the issuance of equity securities, substantial dilution to existing stockholders may result. If the Company raises additional funds by incurring debt financing, the terms of the debt may involve significant cash payment obligations as well as covenants and specific financial ratios that may restrict the Company’s ability to operate its business.
Preclinical and Clinical Trial Accruals	Preclinical and As part of the process of preparing the financial statements, the Company is required to estimate expenses resulting from obligations under contracts with vendors, clinical research organizations and consultants. The financial terms of these contracts vary and may result in payment flows that do not match the periods over which materials or services are provided under such contracts. The Company estimates clinical trial and research agreement related expenses based on the services performed, pursuant to contracts with research institutions and clinical research organizations and other vendors that conduct clinical trials and research on the Company’s behalf. In accruing clinical and research related fees, the Company estimates the time period over which services will be performed and activity expended in each period. If the actual timing of the performance of services or the level of effort varies from the estimate, the Company will adjust the accrual accordingly. Payments made to third parties under these arrangements in advance of the receipt of the related services are recorded as prepaid expenses until the services are rendered.
Stock Repurchases	Stock Repurchases In November 2015, the board of directors approved a share repurchase program (2015 Share Repurchase Program) allowing the CEO or CFO, on behalf of the Company, to repurchase from time to time, in the open market or in privately negotiated transactions, up to $50.0 million of the Company’s outstanding shares of common stock, exclusive of any commissions, markups or expenses. The timing and amounts of any purchases will be based on market conditions and other factors, including price, regulatory requirements and other corporate considerations. The 2015 Share Repurchase Program does not require the purchase of any minimum number of shares and may be suspended, modified or discontinued at any time without prior notice. The Company expects to finance the purchases with existing cash balances. As it is the intent for the repurchased shares to be retired, the Company has elected to account for the shares repurchased under the constructive retirement method. For shares repurchased in excess of par, the Company will allocate the excess value to accumulated deficit.
Stock-Based Compensation	Stock-Based Compensation In the second quarter of 2016, the Company implemented Financial Accounting Standards Board (FASB) Accounting Standard Update (ASU) 2016-09, Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting
Use of Estimates	Use of Estimates The preparation of condensed consolidated financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make certain estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the condensed consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. On an ongoing basis, the Company evaluates its estimates, including those related to the valuation of warrants, stock-based compensation, the valuation allowance for deferred tax assets, preclinical and clinical trial accruals, and the valuation of build-to-suit lease assets. The Company bases its estimates on historical experience and on various other market-specific and relevant assumptions that it believes to be reasonable under the circumstances. Actual results could differ from those estimates.
Basic and Diluted Net Loss Per Share of Common Stock	Basic and Diluted Net Loss per Share of Common Stock Basic net loss per share is calculated by dividing the net loss by the weighted-average number of common shares outstanding for the period. Diluted loss per share is computed similarly to basic loss per share except that the denominator is increased to include the number of additional shares that would have been outstanding if the potential common shares had been issued and if the additional common shares were dilutive. For all periods presented, potentially dilutive securities are excluded from the computation of fully diluted loss per share as their effect is anti-dilutive. The following table details those securities that have been excluded from the computation of potentially dilutive securities: As of September 30, 2016 2015 Outstanding options 6,518,062 9,811,356 Outstanding restricted stock units 859,022 485,150 Outstanding warrants 17,775,257 17,824,525 Total 25,152,341 28,121,031 Amounts in the table above reflect the common stock equivalents of the noted instruments.
Recent Accounting Pronouncements	Recent Accounting Pronouncements In February 2016, the FASB issued or ASU 2016-02, Leases (Topic 842) In March 2016, the FASB issued ASU 2016-09, Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting The Company has adopted the guidance to 1) account for stock-based award forfeitures as they occur rather than apply an estimated forfeiture rate, 2) recognize the income tax effects of awards in the income statement when the awards vest or are settled, thus eliminating additional paid-in capital pools, 3) repurchase more of an employee’s shares for tax withholding purposes without triggering liability accounting, and 4) elected to adopt the amendments related to the presentation of excess tax benefits on the statement of cash flows using a prospective transition method. In June 2016, the FASB issued ASU 2016-13, Financial Instruments – Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments. In August 2016, the FASB issued ASU 2016-15, Statement of Cash Flows (Topic 230) ASU 2016-15 is effective for annual reporting periods, including interim periods within those annual periods, beginning after December 15, 2017, with early adoption permitted. Entities are required to use a retrospective transition approach for all of the issues identified to each period presented. The Company is currently evaluating the impact that the adoption of ASU 2016-15 will have on the Company’s consolidated financial statements and disclosures.

Summary of Significant Accoun21

Summary of Significant Accounting Policies (Tables)	9 Months Ended
	Sep. 30, 2016
Accounting Policies [Abstract]
Securities Excluded from the Computation of Potentially Dilutive Securities	The following table details those securities that have been excluded from the computation of potentially dilutive securities: As of September 30, 2016 2015 Outstanding options 6,518,062 9,811,356 Outstanding restricted stock units 859,022 485,150 Outstanding warrants 17,775,257 17,824,525 Total 25,152,341 28,121,031 Amounts in the table above reflect the common stock equivalents of the noted instruments.

Financial Statement Details (Ta

Financial Statement Details (Tables)	9 Months Ended
	Sep. 30, 2016
Financial Statement Details [Abstract]
Prepaid Expenses and Other Current Assets	As of September 30, 2016 and December 31, 2015, prepaid expenses and other current assets consisted of (in thousands): September 30, 2016 December 31, 2015 (Unaudited) Prepaid services $ 1,866 $ 631 Interest receivable - marketable securities 1,185 911 Prepaid insurance 737 466 Prepaid license fees 462 101 Prepaid legal fees 350 350 Prepaid rent 287 — Due from related parties (Note 8) 76 217 Tax refund receivable — 646 Other 252 — $ 5,215 $ 3,322
Property and Equipment	As of September 30, 2016 and December 31, 2015, property and equipment consisted of (in thousands): September 30, 2016 December 31, 2015 (Unaudited) Construction in progress $ 5,864 $ 5,136 Building under build-to-suit lease 4,348 — Equipment 3,798 241 Leasehold improvements 2,413 182 Software 458 6 Furniture & fixtures 190 125 17,071 5,690 Accumulated depreciation (596 ) (167 ) $ 16,475 $ 5,523
Intangible Assets	As of September 30, 2016 and December 31, 2015, intangible assets consisted of (in thousands): September 30, 2016 December 31, 2015 (Unaudited) Technology license* $ 8,636 $ 8,636 Less accumulated amortization (2,688 ) (1,344 ) $ 5,948 $ 7,292 *Inclusive of $1.5 million intangible asset related to the deferred tax liability, which is not amortized.
Other Assets	As of September 30, 2016 and December 31, 2015, other assets consisted of (in thousands): September 30, 2016 December 31, 2015 (Unaudited) Equipment not placed in service $ 533 $ 624 License fees 192 — Security deposit 137 344 Software license and implementation costs — 391 $ 862 $ 1,359
Accrued Expenses	As of September 30, 2016 and December 31, 2015, accrued expenses consisted of (in thousands): September 30, 2016 December 31, 2015 (Unaudited) Accrued bonus $ 1,622 $ 1,359 Accrued professional and service fees 1,469 367 Accrued construction costs 990 132 Accrued preclinical and clinical trial costs 866 — Accrued compensation 814 348 Accrued franchise and property taxes 14 225 Other 135 144 $ 5,910 $ 2,575
Investment Income, Net	Net investment income includes interest income from all bank accounts as well as marketable securities, net realized gains or losses on sales of investments and the amortization of the premiums and discounts of the investments and is as follows for the three and nine months ended September 30, 2016 and 2015 (in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2016 2015 2016 2015 Interest income $ 1,371 $ 81 $ 3,802 $ 146 Investment amortization accretion expense, net (625 ) — (1,567 ) — Net realized gains on investments 49 — 67 — $ 795 $ 81 $ 2,302 $ 146

Cash Equivalents and Marketab23

Cash Equivalents and Marketable Securities (Tables)	9 Months Ended
	Sep. 30, 2016
Cash Equivalents And Marketable Securities [Abstract]
Schedule of Cash Equivalents and Marketable Securities Available-for-Sale	At September 30, 2016, the detail of the Company’s cash equivalents and marketable securities is as follows (in thousands): September 30, 2016 Amortized Cost Unrealized Unrealized Losses Fair Value Current: Commercial paper $ 16,476 $ — $ — $ 16,476 Government sponsored securities 26,292 32 (1 ) 26,323 Corporate debt securities 147,528 42 (49 ) 147,521 Foreign government bonds 4,005 3 — 4,008 Current portion 194,301 77 (50 ) 194,328 Noncurrent: Government sponsored securities 22,022 83 — 22,105 Corporate debt securities 70,931 270 (54 ) 71,147 Foreign government bonds 1,405 — (2 ) 1,403 Noncurrent portion 94,358 353 (56 ) 94,655 Total $ 288,659 $ 430 $ (106 ) $ 288,983
Available-for-Sale Investments in Unrealized Loss Position	Available-for-sale investments that had been in an unrealized loss position for less than 12 months at September 30, 2016 are as follows (in thousands): September 30, 2016 Estimated Fair Value Gross Unrealized Losses Government sponsored securities $ 5,010 $ (1 ) Corporate debt securities 96,052 (103 ) Foreign government bonds 1,403 (2 ) Total $ 102,465 $ (106 )

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	9 Months Ended
	Sep. 30, 2016
Fair Value Disclosures [Abstract]
Summary of Financial Assets Measured at Fair Value on Recurring Basis	The following table presents the Company’s hierarchy for its assets measured at fair value on a recurring basis as of September 30, 2016 and December 31, 2015: Fair Value Measurements at September 30, 2016 Total Level 1 Level 2 Level 3 Assets: Current: Cash and cash equivalents* $ 16,476 $ — $ 16,476 $ — Government sponsored securities 26,323 — 26,323 — Corporate debt securities 147,521 — 147,521 — Foreign government bonds 4,008 — 4,008 — Noncurrent: Government sponsored securities 22,105 — 22,105 — Corporate debt securities 71,147 — 71,147 — Foreign government bonds 1,403 — 1,403 — Total assets measured at fair value $ 288,983 $ — $ 288,983 $ — *This amount excludes $14.9 million in depository institutions that are classified as Level 1 assets. Fair Value Measurements at December 31, 2015 Total Level 1 Level 2 Level 3 Assets: Current: Cash and cash equivalents* $ 18,039 $ — $ 18,039 $ — Commercial paper 24,917 — 24,917 — Corporate debt securities 86,450 — 86,450 — Foreign government bonds 6,943 — 6,943 — Noncurrent: Corporate debt securities 51,131 — 51,131 — Foreign government bonds 4,004 — 4,004 — Total assets measured at fair value $ 191,484 $ — $ 191,484 $ — *This amount excludes $157.9 million in depository institutions which are classified as Level 1 assets.

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	9 Months Ended
	Sep. 30, 2016
Equity [Abstract]
Summary of Common Stock Repurchases	A summary of common stock repurchases for the nine months ended September 30, 2016 is as follows: Total number of shares purchased Average price paid per share Total number of shares purchased as part of publicly announced plans or programs Maximum approximate dollar value of shares that may yet be purchased under the plans or programs February 300,000 $ 8.50 300,000 $47.5 million May 346,200 $ 6.77 646,200 $45.1 million June 582,400 $ 7.56 1,228,600 $40.7 million August 335,440 $ 7.01 1,564,040 $38.4 million September 30,000 $ 7.40 1,594,040 $38.1 million Total 1,594,040 $ 7.45

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	9 Months Ended
	Sep. 30, 2016
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock Based Compensation Expenses Included in Operations Statement	The following table presents stock-based compensation included on the Company’s condensed consolidated statements of operations (in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2016 2015 2016 2015 (Restated) (Restated) Stock-based compensation expense: Warrants for Class A common stock to an officer $ 14,171 $ 7,636 $ 41,443 $ 129,811 Warrants for Class A common stock to an officer and a director related to Inex Bio, Inc. acquisition — — — 22,747 Employee stock options 3,075 16,424 12,826 20,033 Non-employee stock options — 784 — 3,074 Employee restricted stock units 1,321 14,150 7,851 14,150 Non-employee restricted stock units 102 — 466 — $ 18,669 $ 38,994 $ 62,586 $ 189,815 Stock-based compensation expense in operating expenses: Research and development $ 116 $ 364 $ 680 $ 1,140 Selling, general and administrative 18,553 38,630 61,906 188,675 $ 18,669 $ 38,994 $ 62,586 $ 189,815
Summarizes Stock Option Activity Under Equity Intensive Plan	The following table summarizes stock option activity under the equity incentive plans for the nine months ended September 30, 2016 (in thousands, except for share and per share amounts): Number of Shares Weighted- Average Exercise Aggregate Intrinsic Value Weighted- Average Remaining Contractual (in years) Outstanding at December 31, 2015 8,777,893 $ 5.36 $ 116,273 7.2 Options forfeited (71,627 ) $ 2.00 Options exercised (2,188,204 ) $ 0.67 Outstanding at September 30, 2016 6,518,062 $ 6.97 $ 30,364 6.7 Vested and Exercisable at September 30, 2016 5,041,877
Restricted Stock Units Activity	The following table summarizes the activity for restricted stock units under the 2015 Plan: Number of Restricted Stock Units Outstanding Weighted-Average Grant Date Fair Value Unvested balance at December 31, 2015 1,129,638 $ 20.51 Granted 407,800 $ 7.76 Vested (514,316 ) $ 24.13 Forfeited (164,100 ) $ 12.10 Unvested balance at September 30, 2016 859,022 $ 13.90
Summary of Warrant Activity	The following table summarizes the warrant activity for the nine months ended September 30, 2016: Outstanding at December 31, 2015 17,819,616 Warrants exercised (40,514 ) Warrants forfeited (3,845 ) Outstanding at September 30, 2016 17,775,257 Vested and exercisable at September 30, 2016 12,035,607

Acquisition of Inex Bio, Inc (T

Acquisition of Inex Bio, Inc (Tables)	9 Months Ended
	Sep. 30, 2016
Summary of Purchase Price Paid to Inex Bio	The following summarizes the net consideration paid to Holdings (in thousands): Consideration Total Cash $ 6,518 Fair value of warrants 22,747 Less cash paid to acquire shares in Inex Bio (1,100 ) Net consideration $ 28,165
Summary of Assets and Liabilities Assumed	The following table summarizes the assets acquired and liabilities assumed (in thousands): Cash $ 763 Intangible assets—reacquired rights of Company technology* 8,636 Other assets 42 Investment in Inex Bio (221 ) Deferred tax liability (1,467 ) Accounts payable (1 ) Total assets acquired and liabilities assumed $ 7,752 * Inclusive of $1.5 million intangible asset related to deferred tax liability.
Inex Bio Inc
Summary of Purchase Price Paid to Inex Bio	The purchase price paid to acquire Inex Bio from the other owners is as follows (in thousands): Consideration Total Cash paid by InexBio Holdings, LLC $ 1,100 Cash paid by Company 1,482 Fair value of warrants 5,170 Aggregate purchase price $ 7,752

Description of Business and B28

Description of Business and Basis of Presentation - Additional Information (Detail) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Jan. 01, 2016	Dec. 31, 2015
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Accumulated deficit	$ (358,876)		$ 31,000	$ (250,376)
Net cash used in operating activities	$ (27,840)	$ (14,361)

Summary of Significant Accoun29

Summary of Significant Accounting Policies - Additional Information (Detail)	Nov. 30, 2015USD ($)
Equity [Abstract]
Total amount authorized for repurchase	$ 50,000,000

Summary of Significant Accoun30

Summary of Significant Accounting Policies - Securities Excluded from the Computation of Potentially Dilutive Securities (Detail) - shares	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount	25,152,341	28,121,031
Employee Stock Option
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount	6,518,062	9,811,356
Outstanding Restricted Stock Units
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount	859,022	485,150
Outstanding Warrants
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount	17,775,257	17,824,525

Financial Statement Details - P

Financial Statement Details - Prepaid Expenses and Other Current Assets (Detail) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Financial Statement Details [Abstract]
Prepaid services	$ 1,866	$ 631
Interest receivable - marketable securities	1,185	911
Prepaid insurance	737	466
Prepaid license fees	462	101
Prepaid legal fees	350	350
Prepaid rent	287	0
Due from related parties (Note 8)	76	217
Tax refund receivable	0	646
Other	252	0
Total prepaid expenses and other current assets	$ 5,215	$ 3,322

Financial Statement Details -32

Financial Statement Details - Property and Equipment, Net (Detail) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 17,071	$ 5,690
Accumulated depreciation	(596)	(167)
Property and equipment, net	16,475	5,523
Construction in Progress
Property Plant And Equipment [Line Items]
Property and equipment, gross	5,864	5,136
Building Under Build-to-Suit Lease
Property Plant And Equipment [Line Items]
Property and equipment, gross	4,348	0
Equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	3,798	241
Leasehold Improvements
Property Plant And Equipment [Line Items]
Property and equipment, gross	2,413	182
Software
Property Plant And Equipment [Line Items]
Property and equipment, gross	458	6
Furniture And Fixtures
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 190	$ 125

Financial Statement Details - A

Financial Statement Details - Additional Information (Detail) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Financial Statement Details [Line Items]
Property and equipment, gross	$ 17,071,000		$ 17,071,000		$ 5,690,000
Impairment losses on recognized investments	0	$ 0	0	$ 0
Technology License
Financial Statement Details [Line Items]
Amortization expense	400,000	$ 400,000	1,300,000	$ 800,000
El Segundo California
Financial Statement Details [Line Items]
Non cash build to suit lease asset	5,100,000		5,100,000
Building Under Build-to-Suit Lease
Financial Statement Details [Line Items]
Property and equipment, gross	$ 4,348,000		$ 4,348,000		$ 0

Financial Statement Details - I

Financial Statement Details - Intangible Assets (Detail) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Finite Lived Intangible Assets [Line Items]
Intangible assets, net	$ 5,948	$ 7,292
Technology License
Finite Lived Intangible Assets [Line Items]
Total intangible assets	8,636	8,636
Less accumulated amortization	(2,688)	(1,344)
Intangible assets, net	$ 5,948	$ 7,292

Financial Statement Details -35

Financial Statement Details - Intangible Assets (Parenthetical) (Detail) $ in Millions	Sep. 30, 2016USD ($)
Technology License
Finite Lived Intangible Assets [Line Items]
Intangible asset related to deferred tax liability	$ 1.5

Financial Statement Details - O

Financial Statement Details - Other Assets (Detail) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Financial Statement Details [Abstract]
Equipment not placed in service	$ 533	$ 624
License fees	192	0
Security deposit	137	344
Software license and implementation costs	0	391
Other Assets Noncurrent	$ 862	$ 1,359

Financial Statement Details -37

Financial Statement Details - Accrued Expenses (Detail) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Financial Statement Details [Abstract]
Accrued bonus	$ 1,622	$ 1,359
Accrued professional and service fees	1,469	367
Accrued construction costs	990	132
Accrued preclinical and clinical trial costs	866	0
Accrued compensation	814	348
Accrued franchise and property taxes	14	225
Other	135	144
Accrued Liabilities Current	$ 5,910	$ 2,575

Financial Statement Details -38

Financial Statement Details - Investment Income, Net (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Financial Statement Details [Abstract]
Interest income	$ 1,371	$ 81	$ 3,802	$ 146
Investment amortization accretion expense, net	(625)	0	(1,567)	0
Net realized gains on investments	49	0	67	0
Investment income, net	$ 795	$ 81	$ 2,302	$ 146

Cash Equivalents and Marketab39

Cash Equivalents and Marketable Securities - Additional Information (Detail) $ in Millions	9 Months Ended
	Sep. 30, 2016USD ($)Security
Schedule Of Available For Sale Securities [Line Items]
Available for sale securities maturity period	5 years
Commercial Paper
Schedule Of Available For Sale Securities [Line Items]
Cash equivalent portions included in current fair values | $	$ 16.5
Debt Securities
Schedule Of Available For Sale Securities [Line Items]
Number of available-for-sale securities in unrealized loss positions | Security	47
Maximum
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale securities, period of unrealized loss positions	12 months

Cash Equivalents and Marketab40

Cash Equivalents and Marketable Securities - Schedule of Cash Equivalents and Marketable Securities Available-for-Sale (Detail) $ in Thousands	Sep. 30, 2016USD ($)
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	$ 288,659
Unrealized Gains	430
Unrealized Losses	(106)
Fair Value	288,983
Current Assets
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	194,301
Unrealized Gains	77
Unrealized Losses	(50)
Fair Value	194,328
Current Assets | Commercial Paper
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	16,476
Unrealized Gains	0
Unrealized Losses	0
Fair Value	16,476
Current Assets | Government Sponsored Securities
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	26,292
Unrealized Gains	32
Unrealized Losses	(1)
Fair Value	26,323
Current Assets | Corporate Debt Securities
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	147,528
Unrealized Gains	42
Unrealized Losses	(49)
Fair Value	147,521
Current Assets | Foreign Government Bonds
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	4,005
Unrealized Gains	3
Unrealized Losses	0
Fair Value	4,008
Noncurrent Assets
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	94,358
Unrealized Gains	353
Unrealized Losses	(56)
Fair Value	94,655
Noncurrent Assets | Government Sponsored Securities
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	22,022
Unrealized Gains	83
Unrealized Losses	0
Fair Value	22,105
Noncurrent Assets | Corporate Debt Securities
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	70,931
Unrealized Gains	270
Unrealized Losses	(54)
Fair Value	71,147
Noncurrent Assets | Foreign Government Bonds
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	1,405
Unrealized Gains	0
Unrealized Losses	(2)
Fair Value	$ 1,403

Cash Equivalents and Marketab41

Cash Equivalents and Marketable Securities - Available-for-Sale Investments in Unrealized Loss Position (Detail) $ in Thousands	9 Months Ended
	Sep. 30, 2016USD ($)
Schedule Of Available For Sale Securities [Line Items]
Available for Sale Investments, Estimated Fair Value	$ 102,465
Available for Sale Investments, Gross Unrealized Losses	(106)
Government Sponsored Securities
Schedule Of Available For Sale Securities [Line Items]
Available for Sale Investments, Estimated Fair Value	5,010
Available for Sale Investments, Gross Unrealized Losses	(1)
Corporate Debt Securities
Schedule Of Available For Sale Securities [Line Items]
Available for Sale Investments, Estimated Fair Value	96,052
Available for Sale Investments, Gross Unrealized Losses	(103)
Foreign Government Bonds
Schedule Of Available For Sale Securities [Line Items]
Available for Sale Investments, Estimated Fair Value	1,403
Available for Sale Investments, Gross Unrealized Losses	$ (2)

Fair Value Measurements - Summa

Fair Value Measurements - Summary of Financial Assets Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value	$ 288,983	$ 191,484
Current Assets | Foreign Government Bonds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value	4,008	6,943
Current Assets | Cash and cash equivalents
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value	16,476	18,039
Current Assets | Corporate Debt Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value	147,521	86,450
Current Assets | Commercial Paper
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value		24,917
Current Assets | Government Sponsored Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value	26,323
Noncurrent Assets | Foreign Government Bonds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value	1,403	4,004
Noncurrent Assets | Corporate Debt Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value	71,147	51,131
Noncurrent Assets | Government Sponsored Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value	22,105
Level 1
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value	0	0
Level 1 | Current Assets | Foreign Government Bonds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value	0	0
Level 1 | Current Assets | Cash and cash equivalents
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value	0	0
Level 1 | Current Assets | Corporate Debt Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value	0	0
Level 1 | Current Assets | Commercial Paper
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value		0
Level 1 | Current Assets | Government Sponsored Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value	0
Level 1 | Noncurrent Assets | Foreign Government Bonds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value	0	0
Level 1 | Noncurrent Assets | Corporate Debt Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value	0	0
Level 1 | Noncurrent Assets | Government Sponsored Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value	0
Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value	288,983	191,484
Level 2 | Current Assets | Foreign Government Bonds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value	4,008	6,943
Level 2 | Current Assets | Cash and cash equivalents
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value	16,476	18,039
Level 2 | Current Assets | Corporate Debt Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value	147,521	86,450
Level 2 | Current Assets | Commercial Paper
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value		24,917
Level 2 | Current Assets | Government Sponsored Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value	26,323
Level 2 | Noncurrent Assets | Foreign Government Bonds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value	1,403	4,004
Level 2 | Noncurrent Assets | Corporate Debt Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value	71,147	51,131
Level 2 | Noncurrent Assets | Government Sponsored Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value	22,105
Level 3
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value	0	0
Level 3 | Current Assets | Foreign Government Bonds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value	0	0
Level 3 | Current Assets | Cash and cash equivalents
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value	0	0
Level 3 | Current Assets | Corporate Debt Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value	0	0
Level 3 | Current Assets | Commercial Paper
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value		0
Level 3 | Current Assets | Government Sponsored Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value	0
Level 3 | Noncurrent Assets | Foreign Government Bonds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value	0	0
Level 3 | Noncurrent Assets | Corporate Debt Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value	0	$ 0
Level 3 | Noncurrent Assets | Government Sponsored Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets measured at fair value	$ 0

Fair Value Measurements - Sum43

Fair Value Measurements - Summary of Financial Assets Measured at Fair Value on Recurring Basis (Parenthetical) (Detail) - USD ($) $ in Millions	Sep. 30, 2016	Dec. 31, 2015
Level 1
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash in depository institutions	$ 14.9	$ 157.9

Commitment and Contingencies -

Commitment and Contingencies - Additional Information (Detail) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016USD ($)ft²	Sep. 30, 2015USD ($)	Sep. 30, 2016USD ($)ft²	Sep. 30, 2015USD ($)	Dec. 31, 2015USD ($)
Commitments And Contingencies [Line Items]
Rent expense	$ 800	$ 700	$ 2,200	$ 800
Accumulated depreciation on building	596		596		$ 167
El Segundo California
Commitments And Contingencies [Line Items]
Non cash build to suit lease asset	5,100		$ 5,100
Doug St, LLC
Commitments And Contingencies [Line Items]
Period of agreement			The lease runs from July 2016 through July 2023. The Company has the option to extend the lease for an additional three year term through July 2026. The monthly rent is $0.1 million with annual increases of 3% beginning in July 2017.
Base rent - monthly			$ 100
Percentage of annual increase of base rent			3.00%
Annual percentage increases to base rent commencement date			Jul. 31, 2017
Costs incurred	700		$ 700
Non cash build to suit lease asset	$ 5,100		$ 5,100
Property and equipment estimated useful lives			39 years
Doug St, LLC | El Segundo California
Commitments And Contingencies [Line Items]
Number of square foot of facility leased | ft²	24,250		24,250
Doug St, LLC | Research and Development
Commitments And Contingencies [Line Items]
Rent expense	$ 100
NantWorks
Commitments And Contingencies [Line Items]
Costs incurred	3,500		$ 3,500
Property and equipment estimated useful lives			39 years
Accumulated depreciation on building	4,300		$ 4,300
NantWorks | Research and Development
Commitments And Contingencies [Line Items]
Rent expense	$ 100	$ 100	$ 300	$ 100

Related Party Agreements - Addi

Related Party Agreements - Additional Information (Detail)	1 Months Ended	3 Months Ended		9 Months Ended
	Apr. 30, 2016USD ($)	Sep. 30, 2016USD ($)ft²	Sep. 30, 2015USD ($)	Sep. 30, 2016USD ($)ft²	Sep. 30, 2015USD ($)	Aug. 31, 2016	Dec. 31, 2015USD ($)
Related Party Transaction [Line Items]
Due to related parties		$ 1,853,000		$ 1,853,000			$ 1,352,000
Research and development		8,364,000	$ 4,657,000	19,708,000	$ 7,364,000
Selling, general and administrative		24,423,000	41,810,000	$ 79,678,000	201,810,000
Doug St, LLC
Related Party Transaction [Line Items]
Period of agreement				The lease runs from July 2016 through July 2023. The Company has the option to extend the lease for an additional three year term through July 2026. The monthly rent is $0.1 million with annual increases of 3% beginning in July 2017.
Base rent - monthly				$ 100,000
Percentage of annual increase of base rent				3.00%
Annual percentage increases to base rent commencement date				Jul. 31, 2017
Due to related parties		100,000		$ 100,000
Costs incurred		$ 700,000		$ 700,000
Doug St, LLC | El Segundo California
Related Party Transaction [Line Items]
Number of square foot of facility leased | ft²		24,250		24,250
Doug St, LLC | Research and Development
Related Party Transaction [Line Items]
Rent expense		$ 100,000
Altor | Minimum
Related Party Transaction [Line Items]
Percentage of ownership interest owned by CEO						20.00%
NantBioScience
Related Party Transaction [Line Items]
Research and development	$ 600,000			$ 300,000
Research and development expense, ratable payment period				12 months
NantWorks
Related Party Transaction [Line Items]
Due to related parties		1,700,000		$ 1,700,000
Costs incurred		3,500,000		3,500,000
NantWorks | Shared Services Agreement
Related Party Transaction [Line Items]
Research and development		400,000	100,000	1,200,000	100,000
Selling, general and administrative		800,000	300,000	2,300,000	300,000
NantWorks | Reimbursements | Shared Services Agreement
Related Party Transaction [Line Items]
Research and development		100,000		100,000
Selling, general and administrative		17,000,000		26,000,000
NantWorks | Research and Development
Related Party Transaction [Line Items]
Rent expense		100,000	100,000	300,000	100,000
NantOmics
Related Party Transaction [Line Items]
Due to related parties		100,000		100,000
Research and development		$ 100,000	$ 0	$ 200,000	$ 0
Initial term of agreement entered into with the related party by the entity				5 years
Related party, agreement renewal term				1 year

Spinout of Brink Biologics an46

Spinout of Brink Biologics and Coneksis - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Related Party Transaction [Line Items]
Amount owed to the company	$ 76		$ 76		$ 217
Brink Biologics Inc | Spinout
Related Party Transaction [Line Items]
Royalty revenue	6,000	$ 4,000	13,000	$ 4,000
Revenue from services	21,000	58,000	35,000	58,000
Amount owed to the company	100		100
Coneksis | Spinout
Related Party Transaction [Line Items]
Revenue from services	6,000	$ 3,000	9,000	$ 3,000
Amount owed to the company	$ 15,000		$ 15,000

Stockholders' Equity - Addition

Stockholders' Equity - Additional Information (Detail) - USD ($)	1 Months Ended					3 Months Ended	9 Months Ended
	Sep. 30, 2016	Aug. 31, 2016	Jun. 30, 2016	May 31, 2016	Feb. 29, 2016	Sep. 30, 2016	Sep. 30, 2016	Nov. 30, 2015
Class Of Stock [Line Items]
Total amount authorized for repurchase								$ 50,000,000
Repurchase of common stock, shares	30,000	335,440	582,400	346,200	300,000	365,440	1,594,040
Repurchase of common stock, par value	$ 7.40	$ 7.01	$ 7.56	$ 6.77	$ 8.50		$ 7.45
Repurchase of common stock, value	$ 1,594,040	$ 1,564,040	$ 1,228,600	$ 646,200	$ 300,000		$ 11,898,000
Remained authorized shares for repurchase	$ 38,100,000	$ 38,400,000	$ 40,700,000	$ 45,100,000	$ 47,500,000	$ 38,100,000	38,100,000
Broker commissions on the repurchases							$ 28,000,000
Minimum
Class Of Stock [Line Items]
Repurchase of common stock, par value							$ 6.05
Maximum
Class Of Stock [Line Items]
Repurchase of common stock, par value							$ 8.50

Stockholders' Equity - Summary

Stockholders' Equity - Summary of Common Stock Repurchases (Detail) - USD ($)	1 Months Ended					3 Months Ended	9 Months Ended
	Sep. 30, 2016	Aug. 31, 2016	Jun. 30, 2016	May 31, 2016	Feb. 29, 2016	Sep. 30, 2016	Sep. 30, 2016
Equity [Abstract]
Repurchase of common stock, shares	30,000	335,440	582,400	346,200	300,000	365,440	1,594,040
Repurchase of common stock, par value	$ 7.40	$ 7.01	$ 7.56	$ 6.77	$ 8.50		$ 7.45
Repurchase of common stock, value	$ 1,594,040	$ 1,564,040	$ 1,228,600	$ 646,200	$ 300,000		$ 11,898,000
Remained authorized shares for repurchase	$ 38,100,000	$ 38,400,000	$ 40,700,000	$ 45,100,000	$ 47,500,000	$ 38,100,000	$ 38,100,000

Stock-Based Compensation - Stoc

Stock-Based Compensation - Stock Based Compensation Expenses Related to Statement of Operations (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 18,669	$ 38,994	$ 62,586	$ 189,815
Warrants For Class A Common Stock | Officer
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	14,171	7,636	41,443	129,811
Warrants For Class A Common Stock | Director Related to Inex Bio, Inc
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	0	0	0	22,747
Employee Stock Option
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	3,075	16,424	12,826	20,033
Non Employee Stock Options
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	0	784	0	3,074
Employee Restricted Stock Units | Employees Of Related Company
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	1,321	14,150	7,851	14,150
Non Employee Restricted Stock Units
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	102	0	466	0
Research and Development
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	116	364	680	1,140
Selling, General and Administrative | Employee And Non Employee
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 18,553	$ 38,630	$ 61,906	$ 188,675

Stock-Based Compensation - Addi

Stock-Based Compensation - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Mar. 31, 2016	Sep. 30, 2016	Jan. 01, 2016	Dec. 31, 2015
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Accumulated deficit		$ (358,876)	$ 31,000	$ (250,376)
Additional stock compensation expense	$ 27,000
Warrants
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average period for recognition		1 year 9 months 18 days
Unrecognized compensation cost related to non-vested warrants		$ 58,500
Employee Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Aggregate intrinsic value of stock options exercised		15,800
Unrecognized compensation cost related to non-vested stock options		$ 11,000
Weighted-average period for recognition		2 years 2 months 12 days
Outstanding Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized compensation cost related to non-vested stock options		$ 6,900
Weighted-average period for recognition		3 years 2 months 12 days
Number of Shares, Granted		407,800
Outstanding Restricted Stock Units | Employees Of Related Company
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Shares, Granted		67,500
Employee Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized compensation cost related to non-vested stock options		$ 4,300
Weighted-average period for recognition		3 years 2 months 12 days
Number of Shares, Granted		340,300
Non Employee Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized compensation cost related to non-vested stock options		$ 2,600
Weighted-average period for recognition		3 years 1 month 6 days

Stock-Based Compensation - St51

Stock-Based Compensation - Stock Option Activity (Detail) - Employee Stock Option - USD ($) $ / shares in Units, $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2016	Dec. 31, 2015
Number of Shares
Stock Options, Beginning Balance	8,777,893
Stock Options, Options forfeited	(71,627)
Stock Options, Options exercised	(2,188,204)
Stock Options, Ending Balance	6,518,062	8,777,893
Stock Options, Vested and Exercisable	5,041,877
Weighted Average Exercise Price
Weighted Average Exercise Price, Outstanding Beginning balance	$ 5.36
Weighted Average Exercise Price, Options forfeited	2
Weighted Average Exercise Price, Options exercised	0.67
Weighted Average Exercise Price, Outstanding Ending balance	$ 6.97	$ 5.36
Aggregate Intrinsic Value
Aggregate Intrinsic Value, Outstanding	$ 30,364	$ 116,273
Weighted Average Remaining Contractual Life
Weighted Average Remaining Contractual Life, Outstanding	6 years 8 months 12 days	7 years 2 months 12 days

Stock-Based Compensation - Rest

Stock-Based Compensation - Restricted Stock Units Activity (Detail) - Outstanding Restricted Stock Units	9 Months Ended
	Sep. 30, 2016$ / sharesshares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Shares, Unvested, Beginning balance | shares	1,129,638
Number of Shares, Granted | shares	407,800
Number of Shares, Vested | shares	(514,316)
Number of Shares, Forfeited | shares	(164,100)
Number of Shares, Unvested, Ending balance | shares	859,022
Weighted-Average Grant Date Fair Value, Unvested, beginning balance | $ / shares	$ 20.51
Weighted-Average Grant Date Fair Value, Granted | $ / shares	7.76
Weighted-Average Grant Date Fair Value, Vested | $ / shares	24.13
Weighted-Average Grant Date Fair Value, Forfeited | $ / shares	12.10
Weighted-Average Grant Date Fair Value, Unvested, ending balance | $ / shares	$ 13.90

Stock-Based Compensation - Summ

Stock-Based Compensation - Summary of Warrant Activity (Detail) - Outstanding Warrants	9 Months Ended
	Sep. 30, 2016shares
Warrant [Line Items]
Warrants, Beginning Balance	17,819,616
Warrants exercised	(40,514)
Warrants forfeited	(3,845)
Warrants, Ending Balance	17,775,257
Warrants, Vested and exercisable Ending Balance	12,035,607

Acquisition of Inex Bio, Inc -

Acquisition of Inex Bio, Inc - Additional Information (Detail) - USD ($)	Mar. 30, 2015	Apr. 30, 2015	May 31, 2012	Apr. 30, 2012	Mar. 31, 2015	Sep. 30, 2016	Sep. 30, 2015
Asset Purchase [Line Items]
Number of shares acquired during period			57,000
Stock issued during period, value, acquisitions			$ 200,000
Outstanding shares acquired, percentage			22.20%
Percentage of fully diluted shares acquired			17.40%
Stock-based compensation expense						$ 62,586,000	$ 189,815,000
Inex Bio Holdings, LLC
Asset Purchase [Line Items]
Payments to acquire business						6,500,000
Stock price of warrants	$ 10.72
Term of warrants after closing date of the purchase agreement	15 days
Expected volatility rate	80.00%
Issuance of warrants in Inex Bio acquisition						22,747,000
Stock-based compensation expense						22,700,000
Cash based compensation						$ 5,400,000
Inex Bio Holdings, LLC | Common Class A
Asset Purchase [Line Items]
Warrants issued to acquire shares						2,609,520
Common stock exercise price						$ 2
Proceeds from exercise of warrants		$ 5,200,000
Other Owner Of Inex Bio Inc
Asset Purchase [Line Items]
Payments to acquire business					$ 1,500,000
Stock price of warrants	$ 10.72
Term of warrants after closing date of the purchase agreement	15 days
Expected volatility rate	80.00%
Issuance of warrants in Inex Bio acquisition						$ 5,170,000
Other Owner Of Inex Bio Inc | Common Class A
Asset Purchase [Line Items]
Warrants issued to acquire shares					593,072
Common stock exercise price					$ 2
Proceeds from exercise of warrants		$ 1,200,000
Inex Bio
Asset Purchase [Line Items]
Intangible assets amortizes period						4 years
Cambridge Equities, L.P | Inex Bio Holdings, LLC
Asset Purchase [Line Items]
Ownership percentage of third party business					50.00%
Eragon Ventures, LLC
Asset Purchase [Line Items]
Number of shares acquired during period					220,000
Ownership percentage of third party business					50.00%
Percentage shares acquired					67.30%
Payments to acquire business					$ 1,100,000
Inex license agreement
Asset Purchase [Line Items]
Milestone payment amount					$ 0
Percentage of royalty on net sales				5.00%
Up front fee | Inex license agreement
Asset Purchase [Line Items]
License fees received				$ 300,000
Maximum | Inex license agreement
Asset Purchase [Line Items]
Milestone payment amount				$ 800,000

Acquisition of Inex Bio, Inc 55

Acquisition of Inex Bio, Inc - Summary of Purchase Price Paid to Inex Bio (Detail) - Other Owner Of Inex Bio Inc $ in Thousands	9 Months Ended
	Sep. 30, 2016USD ($)
Asset Purchase [Line Items]
Cash paid by InexBio Holdings, LLC	$ 1,100
Cash paid by Company	1,482
Fair value of warrants	5,170
Aggregate purchase price	$ 7,752

Acquisition of Inex Bio, Inc 56

Acquisition of Inex Bio, Inc - Summary of Assets and Liabilities Assumed (Detail) - Other Owner Of Inex Bio Inc $ in Thousands	Sep. 30, 2016USD ($)
Asset Purchase [Line Items]
Cash	$ 763
Intangible assets—reacquired rights of Company technology	8,636
Other assets	42
Investment in Inex Bio	(221)
Deferred tax liability	(1,467)
Accounts payable	(1)
Total assets acquired and liabilities assumed	$ 7,752

Acquisition of Inex Bio, Inc 57

Acquisition of Inex Bio, Inc - Summary of Assets and Liabilities Assumed (Parenthetical) (Detail) $ in Millions	Sep. 30, 2016USD ($)
Technology License
Asset Purchase [Line Items]
Intangible asset related to deferred tax liability	$ 1.5

Acquisition of Inex Bio, Inc 58

Acquisition of Inex Bio, Inc - Summary of Net Consideration Paid to Holdings (Detail) - Inex Bio Holdings, LLC $ in Thousands	9 Months Ended
	Sep. 30, 2016USD ($)
Asset Purchase [Line Items]
Cash	$ 6,518
Fair value of warrants	22,747
Less cash paid to acquire shares in Inex Bio	(1,100)
Aggregate purchase price	$ 28,165

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($)	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Income Tax [Line Items]
Federal statutory tax rate	34.00%
Company's effective tax rate	0.00%
Tax benefit	$ 100,000	$ 0
Tax benefit in other comprehensive income	200,000	0
ASU 2016-09
Income Tax [Line Items]
Federal excess deduction tax amount	40,000,000
State excess deduction tax amount	34,000,000
Total current year benefit	(6,400,000)
Korea
Income Tax [Line Items]
Tax benefit	$ 300,000	$ 0