Fulgent Genetics (FLGT) 10-K 17 Mar 17 2016 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2016	Mar. 16, 2017	Jun. 30, 2016
Document And Entity Information [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2016
Document Fiscal Year Focus	2,016
Document Fiscal Period Focus	FY
Trading Symbol	FLGT
Entity Registrant Name	Fulgent Genetics, Inc.
Entity Central Index Key	1,674,930
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	No
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Non-accelerated Filer
Entity Common Stock, Shares Outstanding		17,676,256
Entity Public Float			$ 0

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Current assets
Cash and cash equivalents	$ 7,897	$ 489
Marketable securities	12,971
Trade accounts receivable, net of allowance for doubtful accounts of $151 and $75, as of December 31, 2016 and 2015, respectively	4,364	2,118
Other current assets	906	314
Current assets of discontinued operations		9
Total current assets	26,138	2,930
Marketable securities, long term	25,597
Fixed assets, net	6,234	2,469
Deferred tax asset	54
Other long-term assets	17
Non-current assets of discontinued operations		433
Total noncurrent assets	31,902	2,902
Total assets	58,040	5,832
Current liabilities
Accounts payable	2,756	314
Accrued liabilities	436	199
Income tax payable	124
Current liabilities of discontinued operations		173
Total current liabilities	3,316	686
Other long-term liabilities	2
Deferred tax liability	243
Total liabilities	3,561	686
Commitments and contingencies (Note 8)
Stockholders’/ members’ equity
Units 56,000 Class D and 51,000 Class P preferred units authorized, issued and outstanding, 44,000 Class D and 49,000 Class P common units authorized and 34,000 Class D and 45,000 Class P common units issued and outstanding, at December 31, 2015 (Note 9)		58,306
Common stock, $0.0001 par value per share, 200,000 shares authorized, 17,676 shares issued and outstanding at December 31, 2016	2
Preferred stock, $0.0001 par value per share, 1,000 shares authorized, no shares issued or outstanding at December 31, 2016
Additional paid-in capital	109,734
Accumulated other comprehensive loss	(103)
Accumulated deficit	(55,154)	(53,160)
Total stockholders’/ members’ equity	54,479	5,146
Total liabilities and stockholders’/ members’ equity	$ 58,040	$ 5,832

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Allowance for doubtful accounts receivable	$ 151	$ 75
Common stock, par value	$ 0.0001
Common stock, shares authorized	200,000,000
Common stock, shares issued	17,676,000
Common stock, shares outstanding	17,676,000
Preferred stock, par value	$ 0.0001
Preferred stock, shares authorized	1,000,000
Preferred stock, shares issued	0
Preferred stock, shares outstanding	0
Class D Preferred Units
Members' equity, preferred units, authorized		56,000,000
Members' equity, preferred units, issued		56,000,000
Members' equity, preferred units, outstanding		56,000,000
Class P Preferred Units
Members' equity, preferred units, authorized		51,000,000
Members' equity, preferred units, issued		51,000,000
Members' equity, preferred units, outstanding		51,000,000
Class D Common Units
Members' equity, common units, authorized		44,000,000
Members' equity, common units, issued		34,000,000
Members' equity, common units, outstanding		34,000,000
Class P Common Units
Members' equity, common units, authorized		49,000,000
Members' equity, common units, issued		45,000,000
Members' equity, common units, outstanding		45,000,000

Consolidated Statements of Oper

Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended									12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Statement [Abstract]
Revenue	$ 5,854	$ 5,011	$ 3,971	$ 3,440	$ 2,901		$ 2,905	$ 2,182	$ 1,588	$ 18,276	$ 9,576	$ 1,278
Cost of revenue	1,863	2,143	1,411	1,304	2,726		918	772	653	6,722	5,069	936
Gross profit	3,991	2,868	2,560	2,136	175		1,987	1,410	935	11,554	4,507	342
Operating expenses:
Research and development	818	1,523	656	561	3,650		312	252	217	3,558	4,431	521
Selling and marketing	798	893	477	301	1,913		280	243	234	2,469	2,670	581
General and administrative	1,116	1,147	457	1,889	1,956		215	168	79	4,609	2,418	230
Total operating expenses	2,732	3,563	1,590	2,751	7,519		807	663	530	10,636	9,519	1,332
Operating income (loss)	1,259	(695)	970	(615)	(7,344)		1,180	747	405	918	(5,012)	(990)
Interest and other income (expense)	57	5	(5,462)	13	7				20	(5,386)	27	0
Income (loss) before income taxes	1,316	(690)	(4,492)	(602)	(7,337)		1,180	747	425	(4,468)	(4,985)	(990)
Provision for income taxes	503	417								920	0	0
Income (loss) from continuing operations						$ (7,239)				(5,388)	(4,985)	(990)
Income (loss) from discontinued operations						(896)				41	(3,329)	(3,293)
Net income (loss)	$ 813	$ (1,107)	$ (4,492)	$ (602)	$ (7,337)	$ (8,135)	$ 1,180	$ 747	$ 425	$ (5,347)	$ (8,314)	$ (4,283)
Basic and diluted income (loss) per common share:
Continuing operations—common stock										$ (1)	$ (0.61)	$ 0	[1]
Continuing operations:
Weighted-average common shares—outstanding—basic and diluted										13,710	11,842	0
[1]	Basic and diluted income (loss) per common share was calculated prospectively from the date the Class D common units were issued in the Recapitalization in October 2015. See Note 1, Overview and Basis of Presentation, and Note 12, Income (Loss) per Share, to these consolidated financial statements for additional information.

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Statement Of Income And Comprehensive Income [Abstract]
Net loss	$ (5,347)	$ (8,314)	$ (4,283)
Other comprehensive loss, net of tax:
Net unrealized loss on marketable securities	(103)
Comprehensive loss	$ (5,450)	$ (8,314)	$ (4,283)

Consolidated Statements of Stoc

Consolidated Statements of Stockholders'/ Members' Equity - USD ($) $ in Thousands	Total	Initial Public Offering	Class D-2 Preferred Units	Class D-1 Preferred Units	Class D Common Units	Members' Equity	Members' EquityClass D-2 Preferred Units	Members' EquityClass D-1 Preferred Units	Members' EquityClass D Common Units	Stockholders' Equity	Stockholders' EquityInitial Public Offering	Additional Paid-In Capital	Additional Paid-In CapitalInitial Public Offering	Accumulated Other Comprehensive Loss	Accumulated Deficit	Accumulated DeficitClass D-1 Preferred Units	Accumulated DeficitClass D Common Units
Beginning Balance at Dec. 31, 2013	$ 1,967					$ 8,000									$ (6,033)
Beginning Balance, Shares at Dec. 31, 2013						1,000
Capital contribution	4,000					$ 4,000
Net loss	(4,283)														(4,283)
Ending Balance at Dec. 31, 2014	1,684					$ 12,000									(10,316)
Ending Balance, Shares at Dec. 31, 2014						1,000
Capital contribution	3,500					$ 3,500
Recapitalization and deemed distribution						$ 34,530									(34,530)
Recapitalization and deemed distribution, Shares						153,999,000
Equity-based compensation	8,276					$ 8,276
Equity-based compensation, Shares						32,000,000
Net loss	(8,314)														(8,314)
Ending Balance at Dec. 31, 2015	5,146					$ 58,306									(53,160)
Ending Balance, Shares at Dec. 31, 2015						186,000,000
Split-off of Pharma business	(490)					$ (12,390)									11,900
Split-off of Pharma business, Shares						(96,000,000)
Issuance of units / shares, Amount		$ 35,989	$ 32,452				$ 32,452						$ 35,989
Issuance of units / shares							15,395,000				4,830,000
Repurchase and retirement				$ (1,663)	$ (6,587)			$ (1,663)	$ (1,767)								$ (4,820)
Repurchase and retirement, Shares								(4,618,000)	(5,645,000)
Deemed dividend on retirement of Class D-1 preferred units				(3,727)												$ (3,727)
Equity-based compensation (Pre-Reorganization)	2,978					$ 2,978
Equity-based compensation (Pre-Reorganization), Shares						2,500,000
Distribution to Class D-1 preferred unitholder				$ (4,592)				$ (4,592)
Tax distribution to Class D common and preferred unitholders					$ (1,253)				$ (1,253)
Reorganization (Note 1)						$ (72,071)				$ 2		$ 72,069
Reorganization, Shares (Note 1)						(97,632,000)				12,846,000
Equity-based compensation (Post-Reorganization)	1,676											1,676
Other comprehensive loss, net	(103)													$ (103)
Net loss	(5,347)														(5,347)
Ending Balance at Dec. 31, 2016	$ 54,479									$ 2		$ 109,734		$ (103)	$ (55,154)
Ending Balance, Shares at Dec. 31, 2016	17,676,000									17,676,000

Consolidated Statements of Sto7

Consolidated Statements of Stockholders'/ Members' Equity (Parenthetical) $ in Thousands	12 Months Ended
	Dec. 31, 2016USD ($)
Class D-2 Preferred Units
Preferred units issuance cost, net	$ 185

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Cash flow from operating activities:
Net income (loss)	$ (5,347)	$ (8,314)	$ (4,283)
Income (loss) from discontinued operations	41	(3,329)	(3,293)
Loss from continuing operations	(5,388)	(4,985)	(990)
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Equity-based compensation	4,654	8,156
Depreciation and amortization	1,170	575	196
Gain on disposal of fixed assets		(20)
Provision for bad debt	76	48	33
Deferred income taxes	246
Amortization of premium on marketable securities	63
Fair value adjustment recorded upon issuance of D-2 preferred units	5,472
Changes in operating assets and liabilities:
Accounts receivable	(2,322)	(1,779)	(416)
Other current assets	(381)	(163)	(138)
Accounts payable	1,094	132	150
Income taxes payable	124		0
Accrued liabilities	(372)	62	81
Cash provided by (used in) continuing operations	4,436	2,026	(1,084)
Cash used in discontinued operations	(31)	(2,995)	(3,313)
Net cash provided by (used in) operating activities	4,405	(969)	(4,397)
Cash flow from investing activities:
Proceeds from disposal of fixed assets	10	70
Purchases of fixed assets	(3,788)	(2,100)	(731)
Purchase of marketable securities	(39,017)
Cash used in continuing operations	(42,795)	(2,030)	(731)
Cash used in discontinued operations		(175)	(49)
Net cash used in investing activities	(42,795)	(2,205)	(780)
Cash flow from financing activities:
Proceeds from issuance of common stock, net of offering costs	36,790
Cash distributed in split-off of Pharma business	(159)
Capital contributions		3,500	4,000
Distribution to Class D-1 preferred unitholder	(4,592)
Issuance of Class D-2 preferred units, net of issuance costs	26,980
Repurchase and retirement of Class D-1 preferred and Class D common units	(11,977)
Tax distribution to Class D common and preferred unitholders	(1,253)
Net cash provided by financing activities	45,789	3,500	4,000
Net increase (decrease) in cash	7,399	326	(1,177)
Cash balance at beginning of period	498	172	1,349
Cash balance at end of period	7,897	498	$ 172
Supplemental disclosures of cash flow information:
Income taxes paid	550
Supplemental disclosures of non-cash investing and financing activities:
Recapitalization		34,530
Fixed assets included in accounts payable	1,173	$ 17
Initial public offering costs included in accounts payable and accrued expenses	$ 801

Consolidated Statements of Cas9

Consolidated Statements of Cash Flows (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Statement Of Cash Flows [Abstract]
Cash from discontinued operations, beginning	$ 9	$ 0
Cash from discontinued operations, ending	$ 0	$ 9

Overview and Basis of Presentat

Overview and Basis of Presentation	12 Months Ended
	Dec. 31, 2016
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Overview and Basis of Presentation	Note 1. Overview and Basis of Presentation The accompanying consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”). Nature of the Business Fulgent Genetics, Inc., together with its subsidiaries (collectively referred to as the “Company,” unless otherwise noted or the context otherwise requires), is a rapidly growing technology company with an initial focus on offering comprehensive genetic testing to provide physicians with clinically actionable diagnostic information they can use to improve the overall quality of patient care (the “Diagnostics business”). The Company has developed a proprietary technology platform that allows it to offer a broad and flexible test menu and continually expand and improve its proprietary genetic reference library. The Company’s current test menu offers single-gene tests and pre-established, multi-gene, disease-specific panels that collectively test for many genetic conditions, including various cancers, cardiovascular diseases, neurological disorders and pediatric tests. The Company’s existing customer base consists primarily of hospitals and medical institutions, which are frequent and high-volume users of genetic tests and which typically pay the Company directly for its tests. Background and Reorganization The Company was incorporated in the State of Delaware on May 13, 2016. On August 2, 2016, pursuant to the approval of the board of directors of the Company, the Company changed its name from Fulgent Diagnostics, Inc. to Fulgent Genetics, Inc. On September 30, 2016, the Company completed a reorganization pursuant to which Fulgent Therapeutics LLC, a California limited liability company (referred to, together with its former subsidiary unless otherwise noted or the context otherwise requires, as “Fulgent LLC”), became a wholly owned subsidiary of the Company (the “Reorganization”). Prior to the Reorganization, the Company had no material assets and had not conducted any activities other than those incidental to its incorporation and preparation for the initial public offering of its common stock. Following the Reorganization LLC and its other subsidiaries For purposes of these notes and the accompanying consolidated financial statements: (i) Fulgent LLC’s operating agreement, as amended from time to time, is referred to as the “Operating Agreement;” (ii) Fulgent LLC’s equity holders are referred to as “members;” (iii) Fulgent LLC’s authorized, issued and outstanding equity interests prior to the Reorganization are referred to as “units” and consisted of Class D common units and Class D-1 and Class D-2 preferred units; (iv) certain of Fulgent LLC’s Class D common units outstanding prior to the Reorganization constituted profits interests (which are sometimes referred to simply as “profits interests”), which are a type of equity-based award containing a participation threshold (which is sometimes referred to as a “profits interest threshold”) that entitled the recipient of the award to participate in the value of Fulgent LLC only to the extent it appreciated from and after the grant date of the award; and (v) prior to the Reorganization, Fulgent LLC was managed by its Manager, Ming Hsieh, who was also Fulgent LLC’s controlling equity holder. In the Reorganization, each outstanding 7.6 units of Fulgent LLC were cancelled in exchange for one share of the Company’s common stock, such that (i) all outstanding Class D common units of Fulgent LLC (including profits interests) were cancelled in exchange for an aggregate of 4,059,900 shares of the Company’s common stock; (ii) all outstanding Class D-1 preferred units of Fulgent LLC were cancelled in exchange for an aggregate of 6,760,733 shares of the Company’s common stock; (iii) all outstanding Class D-2 preferred units were cancelled in exchange for an aggregate of 2,025,623 shares of the Company’s common stock; (iv) all outstanding options to acquire common units of Fulgent LLC were cancelled in exchange for equivalent options to acquire up to an aggregate of 591,112 shares of the Company’s common stock, and all such options became immediately exercisable to the extent vested; and (v) all outstanding restricted share units relating to common units of Fulgent LLC were cancelled in exchange for equivalent restricted stock units (“RSUs”) relating to 65,789 shares of the Company’s common stock. The Reorganization was accounted for as a common control transaction and no gain or loss was recorded. Recapitalization and Discontinued Operations The Company historically conducted two lines of business: the Diagnostics business, which the Company conducted directly and which is the only business it is presently pursuing, and its former pharmaceutical business (the “Pharma business”), which was conducted by the Company directly until the creation of its wholly owned subsidiary, Fulgent Pharma LLC (“Fulgent Pharma”), in 2015, after which the Pharma business was conducted by Fulgent Pharma. In October 2015, the Company was recapitalized by canceling the then-existing Class A and Class B units and authorizing and issuing equity interests separated into two series based on these two lines of business (the “Recapitalization”). The holders of the Company’s Class D preferred units and Class D voting and non-voting common units had economic rights based on the Diagnostics business, and the holders of the Company’s Class P preferred units and Class P voting and non-voting common units had economic rights based on the Pharma business. The Class D and Class P units that were created by the Recapitalization, sometimes referred to as “tracking” units, were intended to “track,” or reflect, the relative performance of the Diagnostics business and the Pharma business, respectively. After the Recapitalization, there was no single security that represented the performance of the Company as a whole. In the Recapitalization, the holders of Class A units received both Class D and Class P preferred units and the holders of Class B units received both Class D and Class P common units. All of the Class D common units issued in the Recapitalization were subject to a profits interest threshold. In the Recapitalization, the number of units and ownership interests held by each equity holder changed and the nature of the units changed from units that track the performance of the Company as a whole to units that track the separate businesses. As a result, the Recapitalization was accounted for as the extinguishment of Class A and Class B units and the issuance of Class D and Class P preferred and common units, based on the Company’s application of the qualitative approach. The Class D and Class P preferred and common units were recorded at their fair value with the difference between the fair value and carrying value of $34.5 million being recorded as a deemed distribution to Class A and Class B units attributable to the period prior to the issuance of the Class D and Class P units. In April 2016, Fulgent LLC’s Operating Agreement was amended and restated to provide for the distribution of Fulgent Pharma in full redemption and cancellation of Fulgent LLC’s former Class P preferred and common units (collectively, the “Class P units”). On April 4, 2016, the Company completed the split-off of Fulgent Pharma and the Pharma business by redeeming all of the then-outstanding Class P units, distributing to each holder of Class P units substantially identical shares of Fulgent Pharma and causing Fulgent Pharma to assume all then-outstanding options to purchase Class P units. All Class P units were immediately cancelled upon redemption. The split-off of the Pharma business was a pro-rata distribution to all of the holders of Class P units, but did not involve the holders of Fulgent LLC’s Class D common or preferred units. The Manager and controlling equity holder of Fulgent LLC prior to the Reorganization, Mr. Hsieh, is the Manager and controlling equity holder of Fulgent Pharma. As a result, the split-off of the Pharma business was accounted for as a common control transaction and the recorded amount of Fulgent Pharma’s net assets was transferred to the holders of Class P units and no gain or loss was recorded. The split-off of the Pharma business is presented as discontinued operations in the accompanying consolidated financial statements for all periods presented. Significant asset and liability categories of the Pharma business are disclosed on the accompanying consolidated balance sheets. Significant assets and liabilities of the discontinued operations consist of fixed assets and accounts payable. The major components of statements of operations data comprising the income (loss) from discontinued operations are as follows: Year Ended December 31, 2016 2015 2014 (in thousands) Operating expenses: Research and development $ 350 $ 2,217 $ 3,013 General and administrative 9 1,112 280 Total operating expenses 359 3,329 3,293 Operating Income (loss) (359 ) (3,329 ) (3,293 ) Other income 400 — — Income (loss) $ 41 $ (3,329 ) $ (3,293 ) Initial Public Offering On October 4, 2016, the Company completed the initial public offering of its common stock (the “IPO”), in which it issued and sold an aggregate of 4,830,000 shares of common stock (including 630,000 shares issued and sold on October 7, 2016 pursuant to the underwriters’ exercise in full of their option to purchase additional shares) at a public offering price of $9.00 per share. The Company received net proceeds of approximately $36.0 million, after deducting underwriting discounts and commissions of $3.0 million and other offering expenses paid or payable by the Company of approximately $4.4 million. The shares issued and sold in the IPO were registered under the Securities Act of 1933, as amended, on a registration statement on Form S-1 (File No. 333- 213469), as amended (the “Registration Statement”).

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2016
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Note 2. Summary of Significant Accounting Policies Use of Estimates The preparation of consolidated financial statements in conformity with U.S. GAAP requires management to make certain estimates, judgments and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements, as well as the reported amounts of revenue and expenses during the reporting periods. These estimates, judgments and assumptions are based on historical data and experience available at the date of the accompanying consolidated financial statements, as well as various other factors management believes to be reasonable under the circumstances. Actual results could differ from these estimates. On an on-going basis, management evaluates its estimates, primarily those related to: (i) revenue recognition criteria, (ii) accounts receivable and allowances for doubtful accounts, (iii) the useful lives of fixed assets, (iv) estimates of tax liabilities and (v) the valuation of equity-based awards. Principles of Consolidation The accompanying consolidated financial statements include the accounts of the Company and its wholly-owned subsidiaries. All intercompany transactions and balances have been eliminated in consolidation. Cash and Cash Equivalents The Company considers all highly liquid investments with original maturities of three months or less at the date of purchase to be cash equivalents. Cash and cash equivalents include cash held in banks and money market accounts. Cash equivalents are stated at fair value. Accounts Receivable and Allowance for Doubtful Accounts Accounts receivable are stated at the amount the Company expects to collect. The Company performs credit evaluations of its customers and generally does not require collateral. The Company establishes an allowance for doubtful accounts based upon factors surrounding the credit risk of specific customers, historical trends and other information that assists in management’s evaluation. The Company writes off accounts receivable following a review by management and a determination that the receivable is uncollectible. A roll-forward of the activity in the Company’s allowance for doubtful accounts is as follows: December 31, 2016 2015 2014 (in thousands) Allowance for doubtful accounts at beginning of year $ 75 $ 27 $ — Bad debt expense 103 48 33 Deductions (27 ) — (6 ) Allowance for doubtful accounts at end of year $ 151 $ 75 $ 27 Marketable Securities All marketable securities, which consist of debt securities, have been classified as “available for sale” and are carried at fair value. Unrealized gains and losses, net of any related tax effects, are excluded from earnings and are included in other comprehensive loss and reported as a separate component of stockholders’ equity until realized. Realized gains and losses and declines in value judged to be other than temporary, if any, on marketable securities are included in other income (expense), net. The cost of any marketable securities sold is based on the specific-identification method. The amortized cost of marketable securities is adjusted for amortization of premiums and accretion of discounts to maturity. Interest on marketable securities is included in interest income. In accordance with the Company’s investment policy, management invests to diversify credit risk and only invests in securities with high credit quality, including U.S. government securities. The Company regularly evaluates whether declines in the fair value of its investments below their cost are other than temporary. The evaluation includes consideration of the cause of the impairment, including the creditworthiness of the security issuers, the number of securities in an unrealized loss position, the severity and duration of the unrealized losses, whether the Company has the intent to sell the securities, and whether it is more likely than not that the Company will be required to sell the securities before the recovery of their amortized cost basis. If the Company determines that the decline in fair value of an investment is below its accounting basis and this decline is other than temporary, the Company would reduce the carrying value of the security it holds and record a loss for the amount of such decline. The Company has not recorded any realized losses or declines in value judged to be other than temporary on its investments. Fair Value of Financial Instruments The Company's financial instruments consist principally of cash and cash equivalents, marketable securities, accounts receivable and accounts payable. The carrying amounts of certain of these financial instruments, including cash and cash equivalents, accounts receivable and accounts payable, approximate fair value due to their short maturities. Fair value of marketable securities is disclosed in Note 4, Fair Value Measurements, to our consolidated financial statements. Concentrations of Credit Risk, Customers and Suppliers Financial instruments that potentially subject the Company to significant concentrations of credit risk consist primarily of cash, accounts receivable and marketable securities, which consist of debt securities, and cash equivalents. As of December 31, 2016, substantially all of the Company’s cash and cash equivalents were deposited in accounts at financial institutions, and amounts may exceed federally insured limits. Management believes that the Company is not exposed to significant credit risk due to the financial strength of the depository institutions in which its cash and cash equivalents are held. For the year ended December 31, 2016, four customers comprised more than 10% of total accounts receivable as follows: December 31, 2016 2015 2014 Customer A 12% * * Customer B 12% 10% 10% Customer C 11% * * Customer D 11% * * * Less than 10% For the year ended December 31, 2016, Customers A and B each comprised 15% of total revenue, and Customer B also comprised 19% and 11% of our total revenue in 2015 and 2014, respectively. Revenue from the U.S. government was less than 10% of total revenue in 2016, 2015 and 2014. The Company relies on a limited number of suppliers and, in some cases, sole suppliers, for some of its laboratory instruments and materials and it may not be able to find replacements or immediately transition to alternative suppliers if necessary. The Company uses a single supplier for certain laboratory substances used in the chemical reactions incorporated into its processes, referred to as reagents, as well as for sequencers and various other equipment and materials that it uses in its laboratory operations. The Company’s laboratory operations would be interrupted if it encounters delays or difficulties in securing these reagents, sequencers or other equipment or materials or if it needs a substitute or replacement for any of its suppliers and is not able to locate and make arrangements with an acceptable substitute or replacement. The Company believes there are only a few other manufacturers that are currently capable of supplying and servicing the equipment necessary for its laboratory operations, including sequencers and various associated reagents. Fixed Assets Fixed assets are recorded at cost, net of accumulated depreciation and amortization. Depreciation is recorded using the straight-line method over the estimated useful lives of the assets, which is generally between three and five years. Leasehold improvements are capitalized and amortized over the shorter of their expected lives or the applicable lease term, including renewal options, if available. Major replacements and improvements are capitalized, while general repairs and maintenance are expensed as incurred. Software for Internal Use The Company capitalizes certain costs incurred to purchase computer software for internal use. These costs include purchased software packages for Company use. Capitalized computer software costs are amortized over the estimated useful life of the computer software, which is generally three years. Internally developed software costs are capitalized after management has committed to funding the project, it is probable that the project will be completed and the software will be used for its intended function. Costs that do not meet that criteria and costs incurred on projects in the preliminary and post-implementation phases are expensed as incurred. Impairment of Long-Lived Assets The Company evaluates the carrying amount of its long-lived assets whenever events or changes in circumstances indicate that the assets may not be recoverable. An impairment loss would be recognized when estimated future cash flows expected to result from the use of an asset and its eventual disposition is less than the carrying amount of the asset. To date, there have been no such impairment losses. Reporting Segment and Geographic Information Reporting segments are identified as components of an enterprise about which separate discrete financial information is available for evaluation by the chief operating decision-maker in making decisions regarding resource allocation and assessing performance. The Company’s chief operating decision maker is its Chief Executive Officer. The Company views its operations and manages its business in one reporting segment. Revenue Recognition The Company generates revenue from sales of its genetic tests. The Company currently receives payments from: hospitals and medical institutions with which it has direct-bill relationships; research institutions; individual patients and third-party payors. The Company recognizes revenue when all of the following criteria are met: (i) persuasive evidence of an arrangement exists; (ii) delivery has occurred; (iii) the fee is fixed or determinable and (iv) collectability is reasonably assured. Criterion (i) is satisfied when the Company has an arrangement or contract in place. Criterion (ii) is satisfied when the Company delivers a report to the ordering physician or test results to the research institution. Determination of criteria (iii) and (iv) are based on management’s judgments regarding whether the fee is fixed or determinable, and whether the collectability of the fee is reasonably assured. The Company recognizes revenue on a cash basis when it cannot conclude that either criterion (iii) or (iv) has been met. The Company’s test results are delivered electronically, and as such there are no shipping and handling fees incurred by it or billed to customers. The Company’s sales are typically exempt from state sales taxation due to the nature of the results delivered. As a result, the Company currently does not charge customers state sales tax and continues to assess. Deferred Revenue Payments received in advance of services rendered are recorded as deferred revenue and are subsequently recognized as revenue in the period in which the applicable revenue recognition criteria, as described above, are met. Deferred revenue consists primarily of revenue from tests performed for customers that have a limited time period following an initial order to request certain follow-up tests at no additional charge. Overhead Expenses The Company allocates overhead expenses, such as rent and utilities, to cost of revenue and operating expense categories based on headcount. As a result, an overhead expense allocation is reflected in cost of revenue and each operating expense category. Cost of Revenue Cost of revenue reflects the aggregate costs incurred in delivering test results and consists of: personnel costs, including salaries, employee benefit costs, bonuses and equity-based compensation expenses; costs of laboratory supplies; depreciation of laboratory equipment; amortization of leasehold improvements and allocated overhead. Costs associated with performing tests are recorded as tests are processed. Research and Development Expenses Research and development expenses represent costs incurred to develop the Company’s technology and future tests. These costs consist of: personnel costs, including salaries, employee benefit costs, bonuses and equity-based compensation expenses; laboratory supplies; consulting costs and allocated overhead. The Company expenses all research and development costs in the periods in which they are incurred. Selling and Marketing Expenses Selling and marketing expenses consist of: personnel costs, including salaries, employee benefit costs, bonuses and equity-based compensation expenses; customer service expenses; direct marketing expenses; educational and promotional expenses; market research and analysis and allocated overhead. The Company expenses all selling and marketing costs as incurred. General and Administrative Expenses General and administrative expenses include executive, finance and accounting, legal and human resources functions. These expenses consist of: personnel costs, including salaries, employee benefit costs, bonuses and equity-based compensation expenses; audit and legal expenses; consulting costs and allocated overhead. The Company expenses all general and administrative expenses as incurred. Income Taxes Income taxes are accounted for under the asset and liability method. The Company provides for federal, state and foreign income taxes currently payable, as well as for taxes deferred due to timing differences between reporting income and expenses for financial statement purposes versus tax purposes. Deferred tax assets and liabilities are recognized for the future tax consequences attributable to temporary differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases. Deferred tax assets and liabilities are measured using enacted income tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect of a change in income tax rates is recognized as income or expense in the period that includes the enactment date. The Company recognizes the effect of income tax positions only if those positions are more likely than not to be sustained. Recognized income tax positions are measured at the largest amount with a greater than 50% likelihood of being realized. Changes in recognition or measurement are reflected in the period in which the change in judgment occurs. For income tax positions where it is not more likely than not that a tax benefit will be sustained, the Company does not recognize a tax benefit in its consolidated financial statements. The Company records interest and penalties related to uncertain tax positions, if applicable, as a component of income tax expense. Our predecessor, Fulgent LLC, is organized as a limited liability company and its members elected to have Fulgent LLC treated as a partnership for income tax purposes. As a result, for all periods prior to the Reorganization, all taxable income or loss and tax credits of the Company generally were reflected in the personal income tax returns of Fulgent LLC’s members, and no provision for federal and state income taxes was provided in the accompanying consolidated financial statements. The Company became a taxable entity upon completion of the Reorganization on September 30, 2016. Equity-Based Compensation The Company’s employee equity-based awards result in a cost that is measured at fair value on an award’s grant date. Equity-based compensation costs are reflected in the accompanying statements of operations based upon the award recipient’s role within the Company. The Company grants options and RSUs to its employees that generally vest upon the satisfaction of service period criteria typically up to four years. Additionally, the options typically have a contractual term of 10 years. The Company records equity-based compensation expense on stock options and RSUs. Expense for stock options is based on the grant date fair value of the equity-based awards using the accelerated attribution method. Expense for RSUs is based on the grant date fair value of the equity-based awards recognized ratably over the requisite vesting period of the awards. Transactions with non-employees in which goods or services are the consideration received for the grant of equity-based awards are accounted for based on the fair value of the consideration received or the fair value of the equity-based award, whichever is more reliably measurable. The measurement date of the fair value of the equity-based award is the earlier of the date on which the counterparty’s performance is complete or the date on which it is probable that performance will occur. The Company records equity-based compensation expense on stock options based on the measurement date fair value of the equity-based awards using the accelerated attribution method. Expense for RSU is based on the measurement date fair value of the equity-based awards recognized ratably over the requisite vesting period of the awards. Prior to the Reorganization, all option awards granted to employees and non-employees were also subject to a performance condition, such that they did not become exercisable until the occurrence of a qualifying liquidity event or incorporation, each as defined in the 2015 Plan (as defined in Note 10 below). Such an incorporation was deemed to have occurred upon completion of the Reorganization, at which time the options became immediately exercisable, to the extent vested. As a result, prior to the Reorganization, no equity-based compensation expense had been recognized relating to the Company’s options, and at the time of the Reorganization, the Company recognized equity-based compensation expense based on the grant date fair value of all outstanding option awards using the accelerated attribution method. Prior to the Reorganization, the Company also granted awards of Class D and Class P common units to employees and non-employees, some of which were subject to profits interest thresholds. These legally outstanding units allowed the holder to participate along with other unitholders in distributions only after the designated profits interest threshold amounts were met. These units were immediately vested as of the applicable grant date. The Company has recognized compensation cost relating to unit awards, including those subject to profit interest thresholds, based on the fair value of the awards. In the Reorganization, all outstanding Class D common units were converted into shares of the Company’s common stock at a ratio of 7.6 units for one share of common stock. Class P options were not exercisable, whether or not vested, until the earlier of a liquidity event or an incorporation. These options were all assumed by Fulgent Pharma as part of the split-off of the Pharma business and will not result in any recognition of expense by the Company. Comprehensive Loss Comprehensive loss is comprised of net loss and other comprehensive loss. Other comprehensive loss consists of unrealized loss on marketable securities. The Company did not have reclassifications from other comprehensive loss to the loss during the year ended December 31, 2016. Basic and Diluted Net Loss per Share Basic net loss per common share is computed by dividing the net loss attributable to common stockholders by the weighted-average number of common shares outstanding during the period. Diluted net loss per common share is computed by dividing the net loss attributable to common stockholders by the weighted-average number of common shares and dilutive common share equivalents outstanding during the period. Because the Company has reported a net loss attributable to common stockholders for all periods presented, diluted net loss per common share is the same as basic net loss per common share for these periods. Emerging Growth Company Pursuant to the Jumpstart Our Business Startups Act of 2012 (the “JOBS Act”), a company constituting an “emerging growth company” is, among other things, entitled to rely upon certain reduced reporting requirements. The Company is an emerging growth company, but has irrevocably elected not to take advantage of the extended transition period afforded by the JOBS Act for the implementation of new or revised accounting standards. As a result, the Company will comply with new or revised accounting standards on the relevant dates on which adoption of such standards is required for public companies that are not emerging growth companies. Recent Accounting Pronouncements In May 2014, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 2014-09, Revenue from Contracts with Customers (Topic 606), which outlines a comprehensive new revenue recognition model designed to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. In March 2016, the FASB issued ASU No. 2016-08, Revenue from Contracts with Customers (Topic 606)-Principal versus Agent Considerations (Reporting Revenue Gross versus Net), which further clarifies the implementation guidance on principal versus agent considerations contained in ASU 2014-09. In April 2016, the FASB issued ASU No. 2016-10, Revenue from Contracts with Customers (Topic 606)-Identifying Performance Obligations and Licensing, which further clarifies the implementation guidance relating to identifying performance obligations and the licensing implementation guidance. In May 2016, the FASB issued ASU No. 2016-12, Revenue from Contracts with Customers (Topic 606)-Narrow-Scope Improvements and Practical Expedients, which further clarifies guidance on collectability, noncash consideration, presentation of sales tax, practical expedients and transition. In December 2016, the FASB issued ASU No. 2016-20, Technical Corrections and Improvements to Topic 606, Revenue from Contracts with Customers, which makes minor corrections or minor improvements to the codification that are not expected to have a significant effect on current accounting practice or create a significant administrative cost to most entities. These standards, pursuant to ASU No. 2015-14, Revenue from Contracts with Customers-Deferral of the Effective Date (Topic 606) issued by the FASB in August 2015, will be effective for annual periods (including interim periods) beginning after December 15, 2017. The Company has commenced its assessment of these new standards, developed a project plan to guide the implementation, and is evaluating the impact these new standards will have on its consolidated financial statements. The standard can be applied either retrospectively to each period presented or as a cumulative effect adjustment as of the date of adoption . The Company plans to implement these standards effective January 1, 2018 and anticipates adopting based on the modified retrospective method. In January 2016, the FASB issued ASU No. 2016-01, Financial Instruments Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities, which addresses certain aspects of recognition, measurement, presentation, and disclosure of financial instruments, including a provision that requires equity investments (except for investments accounted for under the equity method of accounting) to be measured at fair value, with changes in fair value recognized in current earnings. The ASU is effective for the Company in the first quarter of 2018, with early adoption permitted. The Company is currently evaluating the effect this ASU will have on its consolidated financial statements and related disclosures. In February 2016, the FASB issued ASU No. 2016-02, Leases (Topic 842). The update is aimed at making leasing activities more transparent and comparable, and requires substantially all leases be recognized by lessees on their balance sheet as a right-of-use asset and corresponding lease liability, including leases currently accounted for as operating leases. This guidance will become effective for interim and annual reporting periods beginning with the year ending December 31, 2019. The standard requires the use of a modified retrospective transition approach for existing leases. Early adoption is permitted. The Company is currently evaluating the effect this ASU will have on its consolidated financial statements and related disclosures. In March 2016, the FASB issued ASU No. 2016-09, Stock Compensation (Topic 718); Improvements to Employee Share-Based Payment Accounting. The new guidance simplifies several aspects of the accounting for share-based payment transactions including the income tax consequences, classification of awards as either equity or liabilities, policy election to account for forfeitures as they occur rather than on an estimated basis and classification on the statement of cash flows. The ASU is effective for annual periods beginning after December 15, 2016, including interim periods within that annual period. Early adoption is permitted. The Company elected to early adopt this ASU and has elected to account for forfeitures as they occur. In June 2016, the FASB issued ASU 2016-13, Financial Instruments-Credit Losses: Measurement of Credit Losses on Financial Instruments. ASU 2016-13 replaces the incurred loss impairment methodology in current U.S. GAAP with a methodology that reflects expected credit losses. The update is intended to provide financial statement users with more decision-useful information about the expected credit losses on financial instruments and other commitments to extend credit held by a reporting entity at each reporting date. The standard will be effective for annual reporting periods beginning after December 15, 2019, including interim periods within those reporting periods. Early adoption is permitted. The Company has not yet evaluated the effect this ASU will have on its consolidated financial statements and related disclosures. In August 2016, the FASB issued ASU No. 2016-15, Statement of Cash Flows (Topic 230). The standard clarifies the way certain cash receipts and cash payments are classified with the objective of reducing the existing diversity in practice. The standard is effective for fiscal years and interim periods beginning after December 15, 2017. Early adoption is permitted for all periods beginning after December 15, 2016. The Company is currently evaluating the effect this ASU will have on its consolidated financial statements and related disclosures. In December 2016, the FASB issued ASU 2016-19, Technical Corrections and Improvements, which clarifies and removes inconsistencies in key areas of U.S. GAAP and is effective immediately. The Company adopted this guidance in December 2016 and there was no impact on its consolidated financial statements.

Marketable Securities

Marketable Securities	12 Months Ended
	Dec. 31, 2016
Investments Debt And Equity Securities [Abstract]
Marketable Securities	Note 3. Marketable Securities The Company’s marketable securities consisted of the following: December 31, 2016 Amortized Cost Basis Unrealized Gains Unrealized Losses Aggregate Fair Value (in thousands) Marketable securities: Money market accounts $ 1,580 $ — $ — $ 1,580 Corporate debt securities 38,728 3 (163 ) 38,568 Less: Cash equivalents (1,580 ) — — (1,580 ) Total marketable securities $ 38,728 $ 3 $ (163 ) $ 38,568 The Company did not hold any marketable securities as of December 31, 2015. As of December 31, 2016, the contractual maturities of the Company’s marketable securities less than one year were $13.0 million and the contractual maturities of the Company’s marketable securities greater than one year and less than five years were $25.6 million. Management determined that the gross unrealized losses of $163,000 on the Company’s marketable securities as of December 31, 2016 were temporary in nature. The Company currently does not intend to sell these securities prior to maturity and does not consider these investments to be other-than-temporarily impaired as of December 31, 2016. There were no sales of marketable securities in any of the periods presented.

Fair Value Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2016
Fair Value Disclosures [Abstract]
Fair Value Measurements	Note 4. Fair Value Measurements The authoritative guidance on fair value measurements establishes a framework with respect to measuring assets and liabilities at fair value on a recurring basis and non-recurring basis. Under the framework, fair value is defined as the exit price, or the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants, as of the measurement date. The framework also establishes a three-tier hierarchy for inputs used in measuring fair value that maximizes the use of observable inputs and minimizes the use of unobservable inputs by requiring that the most observable inputs be used when available. Observable inputs are inputs market participants would use in valuing the asset or liability and are developed based on market data obtained from sources independent of our Company. Unobservable inputs are inputs that reflect the Company’s assumptions about the factors market participants would use in valuing the asset or liability and are developed based on the best information available in the circumstances. The hierarchy consists of the following three levels: Level 1: Inputs are quoted prices (unadjusted) in active markets for identical assets or liabilities that the reporting entity can access at the measurement date. Level 2: Inputs are inputs other than quoted prices included within Level 1 that are observable for the asset or liability, either directly or indirectly. Level 3: Inputs are unobservable inputs for the asset or liability. The following table presents information about our financial assets measured at fair value on a recurring basis as of December 31, 2016, based on the three-tier fair value hierarchy: Fair Value Measurements at December 31, 2016 Total Level 1 Level 2 Level 3 (in thousands) Marketable securities: Corporate debt securities $ 38,568 $ — $ 38,568 $ — Money market accounts 1,580 1,580 — — Total marketable securities $ 40,148 $ 1,580 $ 38,568 $ — The Company’s Level 1 assets include money market instruments and are valued based upon observable market prices. Level 2 assets consist of marketable investment securities consisting of corporate bonds. Level 2 securities are valued based upon observable inputs that include reported trades, broker/dealer quotes, bids and offers. As of December 31, 2016, the Company had no investments that were measured using unobservable (Level 3) inputs. There were no transfers between fair value measurement levels during the year ended December 31, 2016. Gross unrealized gains or losses for cash equivalents and marketable securities as of December 31, 2016 were not material. As of December 31, 2016 there were no securities that were in an unrealized loss position for more than 12 months.

Fixed Assets

Fixed Assets	12 Months Ended
	Dec. 31, 2016
Property Plant And Equipment [Abstract]
Fixed Assets	Note 5. Fixed Assets Major classes of fixed assets consisted of the following: December 31, Useful Lives 2016 2015 (in thousands) Computer hardware 3 Years $ 1,293 $ 601 Computer software 3 Years 354 176 Machinery and equipment 5 Years 177 210 Medical lab equipment 5 Years 4,678 2,016 General equipment 3 Years 59 59 Furniture and fixtures 5 Years 86 51 Leasehold improvements Shorter of lease term or estimated useful life 520 256 Assets not yet placed in service 1,114 — Total 8,281 3,369 Less: Accumulated depreciation (2,047 ) (900 ) Property and equipment, net $ 6,234 $ 2,469 Depreciation expense on fixed assets totaled $1.2 million, $575,000 and $196,000 for the years ended December 31, 2016, 2015 and 2014, respectively.

Other Current Assets

Other Current Assets	12 Months Ended
	Dec. 31, 2016
Deferred Costs Capitalized Prepaid And Other Assets Disclosure [Abstract]
Other Current Assets	Note 6. Other Current Assets Other current assets consisted of the following: December 31, 2016 2015 (in thousands) Reagents $ 322 $ 212 Prepaid expenses 375 65 Marketable securities interest receivable 209 — Payroll tax refund — 37 Total $ 906 $ 314 Reagents are used for DNA sequencing applications in the Company’s DNA sequencing equipment.

Reporting Segment and Geographi

Reporting Segment and Geographic Information	12 Months Ended
	Dec. 31, 2016
Segment Reporting [Abstract]
Reporting Segment and Geographic Information	Note 7. Reporting Segment and Geographic Information The Company views its operations and manages its business in one reporting segment. All long-lived assets were located in the United States during the years ended December 31, 2016, 2015 and 2014.Revenue by region was as follows: Year Ended December 31, 2016 2015 2014 (in thousands) Revenue: United States $ 8,258 $ 5,084 $ 640 Foreign: Canada 3,798 2,658 194 China 3,241 — — Other Countries 2,979 1,834 444 Total $ 18,276 $ 9,576 $ 1,278

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2016
Commitments And Contingencies Disclosure [Abstract]
Commitments and Contingencies	Note 8. Commitments and Contingencies Operating Leases The Company has commitments under various non-cancelable operating leases with varying terms through July 2018. The Company has options to renew for two or three years. Minimum Payments Year ending December 31, (in thousands) 2017 $ 252 2018 80 2019 — 2020 — Thereafter — Total minimum lease payments $ 332 The Company’s headquarters is located in Temple City, California, which is comprised of various corporate offices and a laboratory certified under the Clinical Laboratory Improvement Amendments of 1988 (“CLIA”), accredited by the College of American Pathologists (“CAP”) and licensed by the State of California Department of Public Health (“CA DPH”). A second office located in Atlanta, Georgia is used for certain research and development, customer service, report generation and other administrative functions. Rent expense for the years ended December 31, 2016, 2015 and 2014 was approximately $204,000, $158,000 and $64,000, respectively. Purchase Obligations As of December 31, 2016, the Company had purchase obligations of $2.2 million for reagents and equipment. Contingencies From time to time, the Company may be subject to legal proceedings and claims arising in the ordinary course of business. Management does not believe that the outcome of any of these matters will have a material effect on the Company’s consolidated financial position, results of operations or cash flows.

Stockholders__Members_ Equity

Stockholders’/Members’ Equity	12 Months Ended
	Dec. 31, 2016
Equity [Abstract]
Stockholders’/Members’ Equity	Note 9. Stockholders’/Members’ Equity Xi Long Financing In May 2016, Fulgent LLC completed a transaction with Xi Long USA, Inc. (“Xi Long”), an independent investor, and certain members of Fulgent LLC. In this transaction, (i) Xi Long acquired 4,618,421 Class D-1 preferred units and 5,644,737 Class D common units from certain existing members of Fulgent LLC for an aggregate purchase price of $12.0 million, which units were required to be redeemed by Fulgent LLC in exchange for its issuance to Xi Long of an equivalent number of Class D-2 preferred units, and (ii) Fulgent LLC sold an additional 5,131,579 Class D-2 preferred units to Xi Long for gross proceeds of $15.2 million. Fulgent LLC incurred issuance costs of $185,000 for the transaction, resulting in net proceeds to Fulgent LLC of $15.0 million. Fulgent LLC immediately cancelled the redeemed Class D common and Class D-1 preferred units upon completion of the transaction. All Class D-2 preferred units issued to Xi Long in the transaction were converted into an aggregate of 2,025,623 shares of the Company’s common stock upon completion of the Reorganization. This transaction was accounted for as: (i) the retirement of the redeemed Class D common units, (ii) the extinguishment of the redeemed Class D-1 preferred units, with the excess of the consideration transferred over the related carrying amount recorded as a deemed dividend in the amount of $3.7 million, and (iii) the issuance of 15,394,737 Class D-2 preferred units for $32.6 million. As a result of the transaction, Xi Long acquired an aggregate of 15,394,737 Class D-2 preferred units for an aggregate purchase price of $27.2 million, even though, at issuance, the fair value of 15,394,737 Class D-2 preferred units as evidenced by Fulgent LLC’s then most recent third-party valuation was $32.6 million. The $5.5 million difference between the fair value of, and the aggregate consideration paid by Xi Long for, the Class D-2 preferred units issued in the transaction was not attributable to any stated rights or privileges. Rather, Fulgent LLC, Xi Long and the members of Fulgent LLC that were party to the transaction determined to complete the transaction in line with their discussions, notwithstanding that the fair value of the Class D-2 preferred units as evidenced by Fulgent LLC’s third-party valuation had increased from the time these discussions were initiated to the time the transaction was completed. The $5.5 million difference was determined to be a cost of completing the transaction with Xi Long and was recorded as an expense in the accompanying consolidated statement of operations. Reorganization Upon completion of the Reorganization on September 30, 2016, all of Fulgent LLC’s outstanding units were cancelled in exchange for shares of the Company’s common stock, at a ratio of 7.6 units of Fulgent LLC cancelled in exchange for each one share of the Company’s common stock. The following is a summary of the units of Fulgent LLC that were cancelled in exchange for shares of the Company’s common stock: Pre-Reorganization (in thousands) Class D-1 preferred units 51,382 Class D-2 preferred units 15,395 Class D common units 2,500 Class D common units — profit interests 28,355 Total 97,632 The units set forth in the table above were cancelled in exchange for an aggregate of 12,846,256 shares of the Company’s common stock. The members’ equity balance of $72.0 million was reclassified into common stock and additional paid-in capital in the accompanying consolidated balance sheet as of September 30, 2016. Certificate of Incorporation In accordance with the Company’s certificate of incorporation, the Company is authorized to issue 200,000,000 shares of common stock, with a par value of $0.0001 per share, and 1,000,000 shares of preferred stock, with a par value of $0.0001 per share. Holders of the Company’s common stock are entitled to one vote for each share held on all matters submitted to a vote of its stockholders. Holders of the Company’s common stock have no cumulative voting rights. Further, as of December 31, 2016, holders of the Company’s common stock have no preemptive, conversion, redemption or subscription rights and there are no sinking fund provisions applicable to the Company’s common stock. Upon liquidation, dissolution or winding-up of the Company, holders of the Company’s common stock are entitled to share ratably in all assets remaining after payment of all liabilities and the liquidation preferences of any outstanding shares of preferred stock. Subject to preferences that may be applicable to any outstanding shares of preferred stock, holders of the Company’s common stock are entitled to receive dividends, if any, as may be declared from time to time by the Company’s board of directors. As of December 31, 2016, there were no outstanding shares of preferred stock. Distributions In the year ended December 31, 2016, the Company made distributions as follows: (i) the Company paid $1.3 million in tax distributions to the former members of Fulgent LLC based on the income tax liabilities of such former members attributable to Fulgent LLC’s 2016 net taxable income through the date of the Reorganization, and (ii) the Company paid $4.6 million to Mr. Hsieh in his capacity as a member of Fulgent LLC as a return of capital contribution. The Company made no distributions in the year ended December 31, 2015.

Equity-Based Compensation

Equity-Based Compensation	12 Months Ended
	Dec. 31, 2016
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Equity-Based Compensation	Note 10. Equity-Based Compensation Equity-based compensation expense for awards granted to employees is measured based on the fair value of the award on the grant date and recognized in the Company’s consolidated statements of operations over the period during which the employee is required to perform services in exchange for the award (generally the vesting period of the award). Compensation expense for awards with both a service and performance condition is recognized over the period required to achieve both conditions using the accelerated attribution method. The Company estimates the fair value of stock options using the Black-Scholes option valuation model. The Company measures the fair value of RSUs and share awards based on the fair value of the underlying shares on the date of grant. For awards of Fulgent LLC units subject to a profits interest threshold that were granted before the Reorganization, the fair value was measured using the Black-Scholes option valuation model. Prior to the Reorganization, the Company’s employees and other service providers were granted awards under the Fulgent Therapeutics LLC Amended and Restated 2015 Equity Incentive Plan (the “2015 Plan”), which provided for the issuance of equity-based awards to eligible employees, directors and consultants. These awards generally consisted of options, RSUs and units subject to a profits interest threshold. Options granted under the 2015 Plan typically vested over four years and expired 10 years from the date of grant, and were not exercisable, whether or not vested, until the earlier of a liquidity event or incorporation, each as defined in the 2015 Plan. Because the options were subject to both a service condition (as set forth in their vesting schedules) and a performance condition (the occurrence of a qualifying liquidity event or incorporation), no equity-based compensation expense was recognized for these options until the performance condition was deemed to have been satisfied. RSUs granted under the 2015 Plan typically vested over four years. Awards of units subject to profits interest thresholds were typically fully vested at the date of grant. In connection with the Reorganization, the Company approved its 2016 Omnibus Incentive Plan (the “2016 Plan”), which provides for the issuance of up to an aggregate of 2,038,480 shares of the Company’s common stock pursuant to awards granted to eligible employees, directors and consultants. The vesting period, contractual life and other material terms and conditions of awards granted under the 2016 Plan are generally not significantly different from the terms and conditions of awards granted under the 2015 Plan. Additionally, at the effective time of the Reorganization • The 2015 Plan was terminated and no additional awards have been or will be granted thereunder. • Each outstanding option to purchase 7.6 Class D common units of Fulgent LLC was cancelled in exchange for an equivalent option granted under the 2016 Plan to purchase one share of the Company’s common stock. The new options are subject to the same vesting schedule and other material terms and conditions as the cancelled options. The Reorganization was considered an incorporation pursuant to the terms of the 2015 Plan and the performance condition applicable to all options was deemed to have been satisfied. As a result, all of the options became immediately exercisable, to the extent vested, upon completion of the Reorganization. This satisfaction of the performance condition resulted in a cumulative equity-based compensation expense of $1.1 million for the requisite service period related to these options, which the Company recorded in the period in which the Reorganization occurred. The remaining unrecognized equity-based compensation expense related to the options is being recorded over the remaining requisite vesting period of the awards using the accelerated attribution method. • Each outstanding RSU relating to 7.6 Class D common units of Fulgent LLC was cancelled in exchange for an equivalent RSU granted under the 2016 Plan relating to one share of the Company’s common stock. The new RSUs are subject to the same vesting schedule and other material terms and conditions as the cancelled RSUs. Equity-based compensation expense for RSUs is recognized ratably over the requisite vesting period of the awards. • Pursuant to the determination of Mr. Hsieh in his capacity as the Manager of Fulgent LLC prior to the Reorganization, the participation thresholds applicable to all profits interests (i) were ignored and not applied in calculating the number of shares of the Company’s common stock that were issued in exchange for such units in the Reorganization, and (ii) did not carry over to such shares of the Company’s common stock. As a result, the holders of profits interests received shares of the Company’s common stock in the Reorganization at the same ratio, 7.6 units-to-one share, as the holders of Fulgent LLC’s units that were not subject to profits interest thresholds. Ignoring all profits interest thresholds upon the conversion of Fulgent LLC’s profits interests into shares of the Company’s common stock resulted in an equity-based compensation expense of $1.4 million that the Company recorded in the period in which the Reorganization occurred. The Company has included equity-based compensation expense as part of cost of revenue and operating expenses in the accompanying consolidated statements of operations as follows: Year Ended December 31, 2016 2015 (in thousands) Cost of revenue $ 754 $ 1,673 Research and development 1,161 3,241 Selling and marketing 454 1,569 General and administrative 2,285 1,673 Total $ 4,654 $ 8,156 Equity-based compensation expense of $0 and $120,000 recorded in the years ended December 31, 2016 and 2015, respectively, was related to the Pharma business and is included in discontinued operations. Award Activity The below discussions of equity-based award activity, including all share numbers and weighted-average exercise prices, have been adjusted to give retroactive effect to the Reorganization as if it occurred at the beginning of each period presented, with the exception of Class P unit options and Class P unit awards which are not subject to the effect of the Reorganization. Option Awards The following table summarizes activity for options to acquire shares of the Company’s common stock in the years ended December 31, 2016 and 2015: Shares Available for Grant (in thousands) Number of Shares Subject to Options (in thousands) Weighted- Average Exercise Price Weighted- Average Remaining Contractual Life (in years) Aggregate Intrinsic Value (in thousands) Balance at December 31, 2014 — — — — — Authorized 1,974 Granted (274 ) 274 $ 0.38 Exercised — — — Canceled — — — Balance at December 31, 2015 1,700 274 $ 0.38 9.8 $ 645 Authorized 64 Granted (324 ) 324 $ 1.18 Exercised — — — Canceled 42 (42 ) $ 0.38 Balance at December 31, 2016 1,482 556 $ 0.85 9.0 $ 5,976 Exercisable as of December 31, 2016 103 $ 0.38 8.8 $ 1,149 The weighted-average grant date fair value of options to acquire shares of Company’s common stock granted in the years ended December 31, 2016 and 2015 was $7.94 and $2.51, respectively. The remaining unrecognized compensation expense related to these options of $1.6 million for the year ended December 31, 2016, is expected to be recognized over a weighted-average period of 2.9 years. Share and RSU Awards The following table shows grants of share awards and grants of restricted stock units during the years ended December 31, 2016 and 2015: Year Ended December 31, 2016 2015 Employee Non-Employee Employee Non-Employee (in thousands) Share Awards 329 — 3,421 — Restricted Stock Units 364 — — — Share Awards In the year ended December 31, 2016, one employee was granted a share award, which was recorded based on the estimated fair value of shares of common stock on the grant date and resulted in equity-based compensation expense of $1.6 million. These shares were granted outside of the 2015 Plan, were immediately vested and were not subject to a profits interest threshold. In the year ended December 31, 2015, Fulgent LLC granted awards subject to profits interest thresholds, which were fully vested as of the grant date and could have been repurchased in whole or in part by Fulgent LLC at any time during the nine-month period following the termination of the holder’s continuous service. Fulgent LLC’s repurchase right would terminate if not timely exercised by Fulgent LLC and upon the effective date of a registration statement of Fulgent LLC or a successor entity filed under the Securities Act of 1933, as amended, which occurred in connection with the Company’s IPO. The participation threshold for each of the awards granted during the year ended December 31, 2015 was $0.3617 per share, although, as described above, such thresholds were ignored in the Reorganization. Of the awards granted during the period, all were granted under the 2015 Plan except for an award of 2,105,263 shares granted to an employee. These awards were legally outstanding equity of Fulgent LLC as of their respective grant dates that allowed the holder to participate in distributions upon exceeding the designated thresholds. These awards were accounted for at fair value and were considered equity instruments as of their respective grant dates. RSU Awards RSUs are share awards that entitle the holder to receive freely tradable shares of the Company’s common stock upon vesting. The fair value of RSUs is based upon the closing sales price of the Company’s common stock on the grant date. RSUs granted to employees generally vest over a four year period. The RSUs granted in the year ended December 31, 2016 are recorded based on the fair value of shares of common stock on the grant date, which resulted in equity-based compensation expense of $3.5 million to be recognized over four years. As of December 31, 2016, $192,000 has been recognized and the remaining unrecognized compensation expense of $3.3 million related to these RSUs is expected to be recognized over a weighted-average period of 3.8 years. No RSU awards were granted prior to the year ended December 31, 2016. The following table summarizes activity for RSUs relating to shares of the Company’s common stock in the year ended December 31, 2016: Number of Shares (in thousands) Weighted-Average Grant-Date Fair Value Balance at December 31, 2015 — — Granted 364 $ 9.69 Vested and settled — — Forfeited (2 ) $ 9.02 Balance at December 31, 2016 362 $ 9.69 Class P Unit Options and Class P Unit Awards Prior to the split-off of the Pharma business, Fulgent LLC granted awards of options to acquire Class P common units and awards of Class P units subject to profits interest thresholds. The following table summarizes activity for options to acquire Class P common units in the year ended December 31, 2015: Number of Units Subject to Options (in thousands) Weighted- Average Exercise Price Per Unit Weighted- Average Remaining Contractual Life (in years) Aggregate Intrinsic Value Outstanding as of December 31, 2014 — — — — Granted 1,810 $ 0.04 9.8 $ — Exercised — $ — Forfeited/canceled — $ — Outstanding as of December 31, 2015 1,810 $ 0.04 9.8 $ — Vested and expected to vest as of December 31, 2015 1,810 $ 0.04 9.8 $ — The weighted average grant date fair value of options to acquire Class P common units granted in the year ended December 31, 2015 was $0.04. The options were not exercisable, whether or not vested, until the earlier of a liquidity event or an incorporation, each as defined in the Plan, which, as of December 31, 2015, were not probable. As of December 31, 2015, the remaining unrecognized compensation expense related to these options was $64,000. These options were all assumed by Fulgent Pharma as part of the split-off of the Pharma business and did not result in any recognition of expense by the Company. There were no grants of Class P unit awards prior to the year ended December 31, 2015. The following tables show grants of Class P unit awards, all of which were subject to profits interest thresholds, during the year ended December 31, 2015: Employee Non-Employee (in thousands) Profits Interests 4,500 1,500 In the year ended December 31, 2015, Fulgent LLC granted awards subject to profits interest thresholds, which were fully vested as of the grant date and could have been repurchased in whole or in part by Fulgent LLC at any time during the nine-month period following the termination of the holder’s continuous service. Fulgent LLC’s repurchase right would terminate if not timely exercised by Fulgent LLC and upon the effective date of a registration statement of Fulgent LLC or a successor entity filed under the Securities Act of 1933, as amended. The participation threshold for each of the awards granted during the year ended December 31, 2015 was $0.0287 per unit for the Class P units. Of the awards granted during the period, all were granted under the 2015 Plan. The weighted average grant date fair value of Class P common units granted in the year ended December 31, 2015 was $0.02. These awards were legally outstanding equity of Fulgent LLC as of their respective grant dates that allowed the holder to participate in distributions upon exceeding the designated thresholds. These awards were accounted for at fair value and were considered equity instruments as of their respective grant dates. These units were all assumed by Fulgent Pharma as part of the split-off of the Pharma business and do not represent any equity interest in Fulgent LLC or the Company. Fair Value Assumptions Option Awards to Employees The following table sets forth weighted-average assumptions used to estimate the fair value of options to acquire shares of the Company’s common stock (or, prior to the Reorganization, options to acquire common units) granted to employees during the years ended December 31, 2016 and 2015: Year Ended December 31, 2016 2015 Expected term (in years) 6.1 6.1 Risk-free interest rates 1.4 % 1.6 % Dividend yield — — Expected volatility 95.6 % 86.0 % These assumptions and estimates are as follows: • Expected Term. The expected term represents the period that the Company’s equity-based awards are expected to be outstanding. The Company determines the expected term assumption based on the vesting terms, exercise terms and contractual terms of the options, and, in the case of equity-based awards subject to a profits interest threshold granted before the Reorganization, based on the estimated time to liquidity. • Risk-Free Interest Rate. The Company determines the risk-free interest rate by using the equivalent to the expected term based on the U.S. Treasury yield curve in effect as of the date of grant. • Dividend Yield. The assumed dividend yield is based on the Company’s expectation that it will not pay dividends in the foreseeable future, which is consistent with its history of not paying dividends. • Expected Volatility. The Company does not have sufficient history to estimate the volatility of the price of its common equity or the expected term of its options. The Company calculates expected volatility based on historical volatility data of a representative group of companies that are publicly traded. The Company selected representative companies with comparable characteristics to it, including risk profiles and position within the industry, and with historical equity price information sufficient to meet the expected term of the equity-based awards. The Company computes the historical volatility of this selected group using the daily closing prices for the selected companies’ equity during the equivalent period of the calculated expected term of its equity-based awards. The Company will continue to use the representative group volatility information until the historical volatility of its equity is relevant to measure expected volatility for future option grants. • Forfeiture Rate. The Company has early adopted ASU No. 2016-09, Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting, and it has elected to account for forfeitures as they occur. Option Awards to Non-Employees Equity-based compensation expense related to options granted to non-employees is recognized as the options are earned. The fair value of the options is more reliably measurable than the fair value of the services received. The fair value of non-employee options is calculated at each reporting date, using the Black-Scholes option-pricing model, until the award vests or there is a substantial incentive for the non-employee not to perform the required services. The following table sets forth the weighted-average assumptions used to estimate the fair value of options to acquire shares of the Company’s common stock (or, prior to the Reorganization, options to acquire common units) granted to non-employees during the years ended December 31, 2016 and 2015: Year Ended December 31, 2016 2015 Expected term (in years) 10 10 Risk-free interest rates 1.6 % 2.3 % Dividend yield — — Expected volatility 96.9 % 94.8 % The following table sets forth the weighted-average assumptions used to estimate the fair value of options to acquire Class P common units granted to non-employees during the year ended December 31, 2015: Year Ended December 31, 2015 Expected term (in years) 10 Risk-free interest rates 2.3 % Dividend yield — Expected volatility 98.0 % There were no options to acquire Class P common units granted to non-employees during the year ended December 31, 2016. Unit Awards to Employees and Non-Employees The fair value of the unit awards is more reliably measurable than the fair value of the services received for awards granted to non-employees. The fair value of awards subject to profits interest thresholds was calculated at each reporting date using the Black-Scholes option-pricing model. The following table sets forth weighted-average assumptions used to estimate the fair value of Class D and Class P common unit awards subject to profits interest thresholds granted to employees and non-employees during the year ended December 31, 2015 (no such Class D awards were granted to non-employees during such period and no such awards were granted to employees or non-employees during the year ended December 31, 2016): Class D Class P Employee: Expected term (in years) 2 2 Risk-free interest rates 0.6 % 0.6 % Dividend yield 0 0 Expected volatility 68.1 % 75.8 % Non—Employee: Expected term (in years) * 2 Risk-free interest rates * 0.6 % Dividend yield * 0 Expected volatility * 75.6 % * No awards granted Determination of the Fair Value on Grant Dates Historically, for all periods prior to the Company’s initial public offering, the fair value of the common units underlying Fulgent LLC’s equity-based awards was estimated on each grant date by Fulgent LLC’s Manager. In determining fair value, the Manager considered valuations prepared by an independent third party in a manner consistent with the American Institute of Certified Public Accountants Practice Aid, Valuation of Privately-Held Company Equity Securities Issued as Compensation, also known as the Practice Aid. In conducting the valuations, Fulgent LLC considered all objective and subjective factors that it believed to be relevant in each valuation conducted, including management’s best estimate of Fulgent LLC’s business condition, prospects and operating performance at each valuation date. Within the valuations, a range of factors, assumptions and methodologies were used. The significant factors included: • the fact that Fulgent LLC was a privately held company with illiquid securities; • Fulgent LLC’s stage of commercialization; • the likelihood of achieving a liquidity event for Fulgent LLC’s equity, such as an initial public offering, given prevailing market conditions; • Fulgent LLC’s historical operating results; • valuations of comparable public companies; • Fulgent LLC’s discounted future cash flows, based on its projected operating results; and • Fulgent LLC capital structure, including the rights and preferences of its various classes of equity. There are significant judgments and estimates inherent in these valuations. These judgments and estimates include assumptions regarding Fulgent LLC’s future operating performance, stage of commercial growth, average selling price, continued penetration into hospital and medical institution customers, reimbursement from third-party payors, the timing of a potential initial public offering or other liquidity event and the determination of the appropriate valuation method at each valuation date. If Fulgent LLC had made different assumptions, its equity-based compensation expense, income (loss) applicable to common unitholders and income (loss) per unit applicable to common unitholders could have been materially different. The valuations utilized the market approach, the income approach or a combination of both. The market approach and the income approach are both acceptable valuation methods in accordance with the Practice Aid. There are three general methodologies under the market approach: • Guideline Company Method . This method involves the identification and analysis of publicly traded companies that are comparable to the subject company. Pricing multiples of the publicly traded companies are applied to representative financial metrics of the subject company. • Similar Transaction Method . This method includes the identification of transactions in which the targets are comparable to the subject company. This method can also include identification of transactions completed by the most likely buyers in the subject company’s industry. Transaction multiples from the identified transactions are applied to the representative financial metrics of the subject company. • Precedent Transaction Method . By considering the sale price of equity in a recent financing, the equity value can be “backsolved” using an option-pricing model that gives consideration to a company’s capitalization structure and rights of preferred and common equity holders. Under the income approach, enterprise value can be estimated using the discounted cash flow (“DCF”) method, which assumes: • a business is worth today what it can generate in future cash to its owners; • cash received today is worth more than an equal amount of cash received in the future; and • future cash flows can be reasonably estimated. The DCF analysis is comprised of the sum of the present value of two components: discrete period projected cash flows and a residual or terminal value. Additionally, each valuation reflects a marketability discount, resulting from the illiquidity of Fulgent LLC’s common units prior to completion of the Company’s initial public offering. As provided in the Practice Aid, there are several approaches for allocating enterprise value of a privately held company among the securities held in a complex capital structure. The possible methodologies include the probability-weighted expected return method (“PWERM”), the option-pricing method (“OPM”), the current-value method or a hybrid of the PWERM and the OPM, which is referred to as the hybrid method. Under the PWERM, equity is valued based upon the probability-weighted present value of expected future returns, considering various future outcomes available to us, as well as the rights of each class of equity. The OPM treats common equity and preferred equity as call options on the enterprise’s value. The exercise prices associated with these call options vary according to the liquidation preference of the preferred equity, the preferred equity conversion price, the exercise prices of common equity options and other features of a company’s equity capital structure. The current-value method, which is generally only used for early stage companies, is based on first determining enterprise value using a market, income or asset-based approach, and then allocating that value to the preferred equity-based on its liquidation preference or conversion value, whichever would be greater. The valuation of Class D common units related to awards of Class D common units and options to acquire Class D common units granted in 2015 incorporated the income approach (Gordon Growth Analysis) and the market approach (Guideline Public Company Method) in determining value, and Fulgent LLC applied 50% weight to each approach, applying a 35% discount for lack of marketability. For the valuation of Class D common units related to awards of Class D common units and options to acquire Class D common units granted in 2016 prior to completion of the Company’s initial public offering, Fulgent LLC incorporated the PWERM and utilized the market approach (Precedent Transactions Method) incorporating the Xi Long financing, applying a 20% discount for lack of marketability. The valuation of Class P units related to awards of Class P units and options to acquire Class P units granted in the year ended December 31, 2015 incorporated the market approach (Precedent Transactions Method), utilizing OPM to backsolve. After completion of the Company’s initial public offering on October 4, 2016, the fair value of shares of its common stock underlying stock option grants is determined by its board of directors or the compensation committee thereof based on the closing price of its common stock on the date of grant as reported by the NASDAQ Global Market.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Income Taxes	Note 11. Income Taxes Provision for income taxes consists of U.S. federal and state income taxes. A deferred tax liability is recognized for all taxable temporary differences, and a deferred tax asset is recognized for all deductible temporary differences, operating losses and tax credit carryforwards. A valuation allowance is provided when it is more likely than not that some portion or all of a deferred tax asset will not be realized. Prior to the Reorganization, Fulgent LLC was organized as a limited liability company and its members elected to have Fulgent LLC treated as a partnership for income tax purposes. All taxable income or loss and tax credits generally were reflected in the personal income tax returns of the Fulgent LLC’s members. Accordingly, no provision for federal and state income taxes was provided in the accompanying consolidated financial statements prior to the Reorganization. Upon completion of the Reorganization, the Company converted from a pass-through entity for tax purposes to a taxable entity. The change in tax status resulted in $417,000 income tax expense related to the recognition of a net state deferred tax asset of $86,000 and a net federal deferred tax liability of $503,000, which represents the temporary differences in existence on September 30, 2016 between the tax basis of the Company’s assets and liabilities and the amount reported in the financial statements. As of December 31, 2016, the net state deferred tax asset was $54,000 and the net federal deferred tax liability was $243,000. Income tax expense consisted of the following: Year Ended December 31, 2016 (in thousands) Current: Federal $ 616 State 58 Total Current 674 Deferred: Federal 295 State (49 ) Change in valuation allowance — Total Deferred 246 Total income tax expense $ 920 Reconciliation of the difference between the federal statutory income tax rate and the effective income tax rate for the year ended December 31, 2016 is as follows: Year Ended December 31, 2016 Tax provision at federal statutory rate 34.00 % State franchise tax, net of federal income tax benefit 1.98 % Other 0.16 % LLC income not subject to corporate taxes -37.23 % Recognition of pre-merger temporary differences -19.51 % Tax provision -20.60 % The following table summarizes the elements of the deferred tax assets (liabilities) at December 31, 2016: Year Ended December 31, 2016 (in thousands) Deferred tax assets Accrued vacation and other accrued expenses $ 69 Provision for bad debts 54 Equity-based compensation 603 Unrealized loss on investments 58 State income taxes 20 Total deferred tax assets $ 804 Deferred tax liabilities Depreciation $ 993 Total deferred tax liabilities 993 Net deferred tax liabilities $ (189 ) Uncertain Tax Positions The Company is subject to income taxation by the United States government and certain states in which the Company's activities give rise to an income tax filing requirement. The Company does not have income tax filing requirements in any foreign jurisdiction, nor are any taxes withheld from income taxes withheld from foreign sales. As of December 31, 2016, there were no pending tax audits in any jurisdiction. There were no interest or penalties accrued at December 31, 2016. While the Company believes it has adequately provided for all tax positions, amounts asserted by taxing authorities could differ from the Company's accrued positions. Accordingly, additional provisions on federal, state and foreign tax-related matters could be recorded in future periods as revised estimates are settled or otherwise resolved.

Income (Loss) Per Share

Income (Loss) Per Share	12 Months Ended
	Dec. 31, 2016
Earnings Per Share [Abstract]
Income (Loss) per Share	Note 12. Income (Loss) per Share Income (loss) per share for the years ended December 31, 2016 and 2015 was computed as if the Reorganization, including the issuance of one share of common stock in exchange for the cancellation of every 7.6 Class D common and preferred units of Fulgent LLC, had occurred subsequent to the Recapitalization, which occurred in October 2015, with the exception of Class P units which are not subject to the effect of the Reorganization. Income (loss) per share prior to the Recapitalization in October 2015 is not presented. The following is a reconciliation of the denominators of the basic and diluted (loss) per share computations: Years Ended 2016 2015 Continuing Operations Discontinued Operations Total Continuing Operations Discontinued Operations Total (in thousands, except per share data) Loss for the period from October 16, 2015 through December 31, 2015 — — — $ (7,239 ) $ (896 ) $ (8,135 ) Income (loss) $ (5,388 ) $ 41 $ (5,347 ) $ (7,239 ) $ (896 ) $ (8,135 ) Deemed dividend on redemption of Class D-1 preferred unit $ (3,727 ) — $ (3,727 ) — — $ 0 Distribution to Class D-1 preferred unitholder $ (4,592 ) — $ (4,592 ) — — $ 0 Income (loss) allocable to common shareholders $ (13,707 ) $ 41 $ (13,666 ) $ (7,239 ) $ (896 ) $ (8,135 ) Income (loss) allocated to common shareholders $ (13,707 ) $ (7,239 ) Income (loss) allocated to Class P common units — $ 18 — $ (896 ) Income (loss) allocated to Class P preferred units — $ 23 — — Weighted-average common shares—outstanding, basic and diluted 13,710 — 11,842 — Weighted-average Class P common units - profit interests - outstanding, basic and diluted — 10,123 — 5,796 Weighted-average Class P preferred units outstanding, basic and diluted — 13,238 — — Income (loss) per common share from continuing operations, basic and diluted $ (1.00 ) — $ (0.61 ) — Income per Class P common unit - profit interests, basic and diluted — — — $ (0.15 ) Income per Class P preferred unit, basic and diluted — — — — On April 4, 2016, Fulgent LLC completed the split-off of the Pharma business. The financial condition and results of the Pharma business are included in the accompanying consolidated financial statements as discontinued operations for all periods presented, and the weighted-average Class P units related to the Pharma business were computed through the separation date of April 4, 2016. The Class P common and preferred units had the right to participate in earnings and distributions of Fulgent LLC but were not obligated to fund losses. As a result, in periods of net loss, Fulgent LLC allocated losses to the holders of its common units subject to profits interest thresholds, as they were determined to be the most subordinate unit. The following securities have been excluded from the calculation of diluted income (loss) per share for all periods presented because their effect would have been anti-dilutive: Years Ended 2016 2015 Continuing Operations Discontinued Operations Continuing Operations Discontinued Operations (in thousands) Options 490 — 274 — RSUs 79 — — — Class P unit options — — — 1,810 The anti-dilutive shares disclosed above were calculated using the treasury stock method. During the years ended December 31, 2016 and 2015, the Company had options and RSUs that were excluded from the weighted average share calculation for continuing operations due to the Company’s net loss positions. During the year period ended December 31, 2015, the Company had Class P common unit options that were excluded from the weighted average share calculation for discontinued operations because the units were contingently exercisable.

Retirement Plans

Retirement Plans	12 Months Ended
	Dec. 31, 2016
Compensation And Retirement Disclosure [Abstract]
Retirement Plans	Note 13. Retirement Plans The Company offers a 401(k) retirement savings plan (the “401(k) Plan”) for its employees, including its executive officers, who satisfy certain eligibility requirements. The Internal Revenue Code of 1986, as amended, allows eligible employees to defer a portion of their compensation, within prescribed limits, on a pre-tax basis through contributions to the 401(k) Plan. The Company matches contributions to the 401(k) Plan based on the amount of salary deferral contributions the participant makes to the 401(k) Plan. The Company will match up to 3% of an employee’s compensation that the employee contributes to his or her 401(k) Plan account. Total Company matching contributions to the 401(k) Plan were $86,000, $37,000 and $21,000 in the years ended December 31, 2016, 2015 and 2014, respectively.

Related Party

Related Party	12 Months Ended
	Dec. 31, 2016
Related Party Transactions [Abstract]
Related Party	Note 14. Related Party Dr. Yun Yen, who is a member of the Company’s Board of Directors and a stockholder, serves as the President and Chairman of the Board for the Sino-American Cancer Foundation (the “Foundation”) and served as the President for the University Taipei Medical University (the “University”), from August 1, 2011 through July 31, 2016 and currently serves as an honorary Chairman of the Board for the University. The Company performs research testing services for the Foundation. The Company recognized $150,000 during the year ended December 31, 2016, as consideration for such services. No services were rendered to the Foundation in 2015 and 2014. Additionally, the Company subleases certain of its headquarters facilities to the Foundation. The Company recognized $28,000 and $11,500 in the years ended December 31, 2016 and 2015, respectively, as consideration for such sublease. The Company performs genetic sequencing services for the University. The Company recognized $353,000 and $13,000 as consideration for such services in the years ended December 31, 2016 and 2015, respectively. As of December 31, 2016 and 2015, $0 and $0 was due from the Foundation and $29,550 and $0 was due from the University, respectively.

Selected Quarterly Financial Da

Selected Quarterly Financial Data (Unaudited)	12 Months Ended
	Dec. 31, 2016
Quarterly Financial Information Disclosure [Abstract]
Selected Quarterly Financial Information (Unaudited)	Note 15. Selected Quarterly Financial Data (Unaudited) The tables below set forth the Company’s quarterly consolidated statements of operations data for the eight quarters ended December 31, 2016. In the opinion of management, this quarterly data has been prepared on the same basis as the consolidated financial statements and includes all adjustments, consisting of normal recurring adjustments, necessary for a fair presentation of the results of operations for the periods presented. See Item 7. “Management’s Discussion and Analysis of Financial Condition and Results of Operations,” in this report for descriptions of the effects of any extraordinary, unusual or infrequently occurring items recognized in any of the periods covered by this data. The results for any one quarter are not indicative of the results to be expected in the current period or any future period Three Months Ended Dec. 31, 2016 Sept. 30, 2016 June 30, 2016 Mar. 31, 2016 Dec. 31, 2015 Sept. 30, 2015 June 30, 2015 Mar. 31, 2015 (in thousands) Statement of Operations Data: Revenue $ 5,854 $ 5,011 $ 3,971 $ 3,440 $ 2,901 $ 2,905 $ 2,182 $ 1,588 Cost of revenue 1,863 2,143 1,411 1,304 2,726 918 772 653 Gross profit 3,991 2,868 2,560 2,136 175 1,987 1,410 935 Operating expenses: Research and development 818 1,523 656 561 3,650 312 252 217 Selling and marketing 798 893 477 301 1,913 280 243 234 General and administrative 1,116 1,147 457 1,889 1,956 215 168 79 Total operating expenses 2,732 3,563 1,590 2,751 7,519 807 663 530 Operating income (loss) 1,259 (695 ) 970 (615 ) (7,344 ) 1,180 747 405 Interest and other income (expense) 57 5 (5,462 ) 13 7 - - 20 Income (loss) before income taxes 1,316 (690 ) (4,492 ) (602 ) (7,337 ) 1,180 747 425 Provision for income taxes 503 417 - - - - - - Net income (loss) $ 813 $ (1,107 ) $ (4,492 ) $ (602 ) $ (7,337 ) $ 1,180 $ 747 $ 425 Net income (loss) per common share: Basic $ 0.05 $ (0.44 ) $ (5.49 ) $ (0.02 ) $ (0.61 ) * * * Diluted $ 0.05 $ (0.44 ) $ (5.49 ) $ (0.02 ) $ (0.61 ) * * * *Basic and diluted income (loss) per common share was calculated prospectively from the date the Class D common units were issued in the Recapitalization in October 2015 . See Note 1, Overview and Basis of Presentation, and Note 12, Income (Loss) per Share, to these consolidated financial statements for additional information.

Summary of Significant Accoun25

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2016
Accounting Policies [Abstract]
Use of Estimates	Use of Estimates The preparation of consolidated financial statements in conformity with U.S. GAAP requires management to make certain estimates, judgments and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements, as well as the reported amounts of revenue and expenses during the reporting periods. These estimates, judgments and assumptions are based on historical data and experience available at the date of the accompanying consolidated financial statements, as well as various other factors management believes to be reasonable under the circumstances. Actual results could differ from these estimates. On an on-going basis, management evaluates its estimates, primarily those related to: (i) revenue recognition criteria, (ii) accounts receivable and allowances for doubtful accounts, (iii) the useful lives of fixed assets, (iv) estimates of tax liabilities and (v) the valuation of equity-based awards.
Principles of Consolidation	Principles of Consolidation The accompanying consolidated financial statements include the accounts of the Company and its wholly-owned subsidiaries. All intercompany transactions and balances have been eliminated in consolidation.
Cash and Cash Equivalents	Cash and Cash Equivalents The Company considers all highly liquid investments with original maturities of three months or less at the date of purchase to be cash equivalents. Cash and cash equivalents include cash held in banks and money market accounts. Cash equivalents are stated at fair value.
Accounts Receivable and Allowance for Doubtful Accounts	Accounts Receivable and Allowance for Doubtful Accounts Accounts receivable are stated at the amount the Company expects to collect. The Company performs credit evaluations of its customers and generally does not require collateral. The Company establishes an allowance for doubtful accounts based upon factors surrounding the credit risk of specific customers, historical trends and other information that assists in management’s evaluation. The Company writes off accounts receivable following a review by management and a determination that the receivable is uncollectible. A roll-forward of the activity in the Company’s allowance for doubtful accounts is as follows: December 31, 2016 2015 2014 (in thousands) Allowance for doubtful accounts at beginning of year $ 75 $ 27 $ — Bad debt expense 103 48 33 Deductions (27 ) — (6 ) Allowance for doubtful accounts at end of year $ 151 $ 75 $ 27
Marketable Securities	Marketable Securities All marketable securities, which consist of debt securities, have been classified as “available for sale” and are carried at fair value. Unrealized gains and losses, net of any related tax effects, are excluded from earnings and are included in other comprehensive loss and reported as a separate component of stockholders’ equity until realized. Realized gains and losses and declines in value judged to be other than temporary, if any, on marketable securities are included in other income (expense), net. The cost of any marketable securities sold is based on the specific-identification method. The amortized cost of marketable securities is adjusted for amortization of premiums and accretion of discounts to maturity. Interest on marketable securities is included in interest income. In accordance with the Company’s investment policy, management invests to diversify credit risk and only invests in securities with high credit quality, including U.S. government securities. The Company regularly evaluates whether declines in the fair value of its investments below their cost are other than temporary. The evaluation includes consideration of the cause of the impairment, including the creditworthiness of the security issuers, the number of securities in an unrealized loss position, the severity and duration of the unrealized losses, whether the Company has the intent to sell the securities, and whether it is more likely than not that the Company will be required to sell the securities before the recovery of their amortized cost basis. If the Company determines that the decline in fair value of an investment is below its accounting basis and this decline is other than temporary, the Company would reduce the carrying value of the security it holds and record a loss for the amount of such decline. The Company has not recorded any realized losses or declines in value judged to be other than temporary on its investments.
Fair Value of Financial Instruments	Fair Value of Financial Instruments The Company's financial instruments consist principally of cash and cash equivalents, marketable securities, accounts receivable and accounts payable. The carrying amounts of certain of these financial instruments, including cash and cash equivalents, accounts receivable and accounts payable, approximate fair value due to their short maturities. Fair value of marketable securities is disclosed in Note 4, Fair Value Measurements, to our consolidated financial statements.
Concentrations of Credit Risk, Customers and Suppliers	Concentrations of Credit Risk, Customers and Suppliers Financial instruments that potentially subject the Company to significant concentrations of credit risk consist primarily of cash, accounts receivable and marketable securities, which consist of debt securities, and cash equivalents. As of December 31, 2016, substantially all of the Company’s cash and cash equivalents were deposited in accounts at financial institutions, and amounts may exceed federally insured limits. Management believes that the Company is not exposed to significant credit risk due to the financial strength of the depository institutions in which its cash and cash equivalents are held. For the year ended December 31, 2016, four customers comprised more than 10% of total accounts receivable as follows: December 31, 2016 2015 2014 Customer A 12% * * Customer B 12% 10% 10% Customer C 11% * * Customer D 11% * * * Less than 10% For the year ended December 31, 2016, Customers A and B each comprised 15% of total revenue, and Customer B also comprised 19% and 11% of our total revenue in 2015 and 2014, respectively. Revenue from the U.S. government was less than 10% of total revenue in 2016, 2015 and 2014. The Company relies on a limited number of suppliers and, in some cases, sole suppliers, for some of its laboratory instruments and materials and it may not be able to find replacements or immediately transition to alternative suppliers if necessary. The Company uses a single supplier for certain laboratory substances used in the chemical reactions incorporated into its processes, referred to as reagents, as well as for sequencers and various other equipment and materials that it uses in its laboratory operations. The Company’s laboratory operations would be interrupted if it encounters delays or difficulties in securing these reagents, sequencers or other equipment or materials or if it needs a substitute or replacement for any of its suppliers and is not able to locate and make arrangements with an acceptable substitute or replacement. The Company believes there are only a few other manufacturers that are currently capable of supplying and servicing the equipment necessary for its laboratory operations, including sequencers and various associated reagents.
Fixed Assets	Fixed Assets Fixed assets are recorded at cost, net of accumulated depreciation and amortization. Depreciation is recorded using the straight-line method over the estimated useful lives of the assets, which is generally between three and five years. Leasehold improvements are capitalized and amortized over the shorter of their expected lives or the applicable lease term, including renewal options, if available. Major replacements and improvements are capitalized, while general repairs and maintenance are expensed as incurred.
Software for Internal Use	Software for Internal Use The Company capitalizes certain costs incurred to purchase computer software for internal use. These costs include purchased software packages for Company use. Capitalized computer software costs are amortized over the estimated useful life of the computer software, which is generally three years. Internally developed software costs are capitalized after management has committed to funding the project, it is probable that the project will be completed and the software will be used for its intended function. Costs that do not meet that criteria and costs incurred on projects in the preliminary and post-implementation phases are expensed as incurred.
Impairment of Long-Lived Assets	Impairment of Long-Lived Assets The Company evaluates the carrying amount of its long-lived assets whenever events or changes in circumstances indicate that the assets may not be recoverable. An impairment loss would be recognized when estimated future cash flows expected to result from the use of an asset and its eventual disposition is less than the carrying amount of the asset. To date, there have been no such impairment losses.
Reporting Segment and Geographic Information	Reporting Segment and Geographic Information Reporting segments are identified as components of an enterprise about which separate discrete financial information is available for evaluation by the chief operating decision-maker in making decisions regarding resource allocation and assessing performance. The Company’s chief operating decision maker is its Chief Executive Officer. The Company views its operations and manages its business in one reporting segment.
Revenue Recognition	Revenue Recognition The Company generates revenue from sales of its genetic tests. The Company currently receives payments from: hospitals and medical institutions with which it has direct-bill relationships; research institutions; individual patients and third-party payors. The Company recognizes revenue when all of the following criteria are met: (i) persuasive evidence of an arrangement exists; (ii) delivery has occurred; (iii) the fee is fixed or determinable and (iv) collectability is reasonably assured. Criterion (i) is satisfied when the Company has an arrangement or contract in place. Criterion (ii) is satisfied when the Company delivers a report to the ordering physician or test results to the research institution. Determination of criteria (iii) and (iv) are based on management’s judgments regarding whether the fee is fixed or determinable, and whether the collectability of the fee is reasonably assured. The Company recognizes revenue on a cash basis when it cannot conclude that either criterion (iii) or (iv) has been met. The Company’s test results are delivered electronically, and as such there are no shipping and handling fees incurred by it or billed to customers. The Company’s sales are typically exempt from state sales taxation due to the nature of the results delivered. As a result, the Company currently does not charge customers state sales tax and continues to assess.
Deferred Revenue	Deferred Revenue Payments received in advance of services rendered are recorded as deferred revenue and are subsequently recognized as revenue in the period in which the applicable revenue recognition criteria, as described above, are met. Deferred revenue consists primarily of revenue from tests performed for customers that have a limited time period following an initial order to request certain follow-up tests at no additional charge.
Overhead Expenses	Overhead Expenses The Company allocates overhead expenses, such as rent and utilities, to cost of revenue and operating expense categories based on headcount. As a result, an overhead expense allocation is reflected in cost of revenue and each operating expense category.
Cost of Revenue	Cost of Revenue Cost of revenue reflects the aggregate costs incurred in delivering test results and consists of: personnel costs, including salaries, employee benefit costs, bonuses and equity-based compensation expenses; costs of laboratory supplies; depreciation of laboratory equipment; amortization of leasehold improvements and allocated overhead. Costs associated with performing tests are recorded as tests are processed.
Research and Development Expenses	Research and Development Expenses Research and development expenses represent costs incurred to develop the Company’s technology and future tests. These costs consist of: personnel costs, including salaries, employee benefit costs, bonuses and equity-based compensation expenses; laboratory supplies; consulting costs and allocated overhead. The Company expenses all research and development costs in the periods in which they are incurred.
Selling and Marketing Expenses	Selling and Marketing Expenses Selling and marketing expenses consist of: personnel costs, including salaries, employee benefit costs, bonuses and equity-based compensation expenses; customer service expenses; direct marketing expenses; educational and promotional expenses; market research and analysis and allocated overhead. The Company expenses all selling and marketing costs as incurred.
General and Administrative Expenses	General and Administrative Expenses General and administrative expenses include executive, finance and accounting, legal and human resources functions. These expenses consist of: personnel costs, including salaries, employee benefit costs, bonuses and equity-based compensation expenses; audit and legal expenses; consulting costs and allocated overhead. The Company expenses all general and administrative expenses as incurred.
Income Taxes	Income Taxes Income taxes are accounted for under the asset and liability method. The Company provides for federal, state and foreign income taxes currently payable, as well as for taxes deferred due to timing differences between reporting income and expenses for financial statement purposes versus tax purposes. Deferred tax assets and liabilities are recognized for the future tax consequences attributable to temporary differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases. Deferred tax assets and liabilities are measured using enacted income tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect of a change in income tax rates is recognized as income or expense in the period that includes the enactment date. The Company recognizes the effect of income tax positions only if those positions are more likely than not to be sustained. Recognized income tax positions are measured at the largest amount with a greater than 50% likelihood of being realized. Changes in recognition or measurement are reflected in the period in which the change in judgment occurs. For income tax positions where it is not more likely than not that a tax benefit will be sustained, the Company does not recognize a tax benefit in its consolidated financial statements. The Company records interest and penalties related to uncertain tax positions, if applicable, as a component of income tax expense. Our predecessor, Fulgent LLC, is organized as a limited liability company and its members elected to have Fulgent LLC treated as a partnership for income tax purposes. As a result, for all periods prior to the Reorganization, all taxable income or loss and tax credits of the Company generally were reflected in the personal income tax returns of Fulgent LLC’s members, and no provision for federal and state income taxes was provided in the accompanying consolidated financial statements. The Company became a taxable entity upon completion of the Reorganization on September 30, 2016.
Equity-Based Compensation	Equity-Based Compensation The Company’s employee equity-based awards result in a cost that is measured at fair value on an award’s grant date. Equity-based compensation costs are reflected in the accompanying statements of operations based upon the award recipient’s role within the Company. The Company grants options and RSUs to its employees that generally vest upon the satisfaction of service period criteria typically up to four years. Additionally, the options typically have a contractual term of 10 years. The Company records equity-based compensation expense on stock options and RSUs. Expense for stock options is based on the grant date fair value of the equity-based awards using the accelerated attribution method. Expense for RSUs is based on the grant date fair value of the equity-based awards recognized ratably over the requisite vesting period of the awards. Transactions with non-employees in which goods or services are the consideration received for the grant of equity-based awards are accounted for based on the fair value of the consideration received or the fair value of the equity-based award, whichever is more reliably measurable. The measurement date of the fair value of the equity-based award is the earlier of the date on which the counterparty’s performance is complete or the date on which it is probable that performance will occur. The Company records equity-based compensation expense on stock options based on the measurement date fair value of the equity-based awards using the accelerated attribution method. Expense for RSU is based on the measurement date fair value of the equity-based awards recognized ratably over the requisite vesting period of the awards. Prior to the Reorganization, all option awards granted to employees and non-employees were also subject to a performance condition, such that they did not become exercisable until the occurrence of a qualifying liquidity event or incorporation, each as defined in the 2015 Plan (as defined in Note 10 below). Such an incorporation was deemed to have occurred upon completion of the Reorganization, at which time the options became immediately exercisable, to the extent vested. As a result, prior to the Reorganization, no equity-based compensation expense had been recognized relating to the Company’s options, and at the time of the Reorganization, the Company recognized equity-based compensation expense based on the grant date fair value of all outstanding option awards using the accelerated attribution method. Prior to the Reorganization, the Company also granted awards of Class D and Class P common units to employees and non-employees, some of which were subject to profits interest thresholds. These legally outstanding units allowed the holder to participate along with other unitholders in distributions only after the designated profits interest threshold amounts were met. These units were immediately vested as of the applicable grant date. The Company has recognized compensation cost relating to unit awards, including those subject to profit interest thresholds, based on the fair value of the awards. In the Reorganization, all outstanding Class D common units were converted into shares of the Company’s common stock at a ratio of 7.6 units for one share of common stock. Class P options were not exercisable, whether or not vested, until the earlier of a liquidity event or an incorporation. These options were all assumed by Fulgent Pharma as part of the split-off of the Pharma business and will not result in any recognition of expense by the Company.
Comprehensive Loss	Comprehensive Loss Comprehensive loss is comprised of net loss and other comprehensive loss. Other comprehensive loss consists of unrealized loss on marketable securities. The Company did not have reclassifications from other comprehensive loss to the loss during the year ended December 31, 2016.
Basic and Diluted Net Loss per Share	Basic and Diluted Net Loss per Share Basic net loss per common share is computed by dividing the net loss attributable to common stockholders by the weighted-average number of common shares outstanding during the period. Diluted net loss per common share is computed by dividing the net loss attributable to common stockholders by the weighted-average number of common shares and dilutive common share equivalents outstanding during the period. Because the Company has reported a net loss attributable to common stockholders for all periods presented, diluted net loss per common share is the same as basic net loss per common share for these periods.
Emerging Growth Company	Emerging Growth Company Pursuant to the Jumpstart Our Business Startups Act of 2012 (the “JOBS Act”), a company constituting an “emerging growth company” is, among other things, entitled to rely upon certain reduced reporting requirements. The Company is an emerging growth company, but has irrevocably elected not to take advantage of the extended transition period afforded by the JOBS Act for the implementation of new or revised accounting standards. As a result, the Company will comply with new or revised accounting standards on the relevant dates on which adoption of such standards is required for public companies that are not emerging growth companies.
Recent Accounting Pronouncements	Recent Accounting Pronouncements In May 2014, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 2014-09, Revenue from Contracts with Customers (Topic 606), which outlines a comprehensive new revenue recognition model designed to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. In March 2016, the FASB issued ASU No. 2016-08, Revenue from Contracts with Customers (Topic 606)-Principal versus Agent Considerations (Reporting Revenue Gross versus Net), which further clarifies the implementation guidance on principal versus agent considerations contained in ASU 2014-09. In April 2016, the FASB issued ASU No. 2016-10, Revenue from Contracts with Customers (Topic 606)-Identifying Performance Obligations and Licensing, which further clarifies the implementation guidance relating to identifying performance obligations and the licensing implementation guidance. In May 2016, the FASB issued ASU No. 2016-12, Revenue from Contracts with Customers (Topic 606)-Narrow-Scope Improvements and Practical Expedients, which further clarifies guidance on collectability, noncash consideration, presentation of sales tax, practical expedients and transition. In December 2016, the FASB issued ASU No. 2016-20, Technical Corrections and Improvements to Topic 606, Revenue from Contracts with Customers, which makes minor corrections or minor improvements to the codification that are not expected to have a significant effect on current accounting practice or create a significant administrative cost to most entities. These standards, pursuant to ASU No. 2015-14, Revenue from Contracts with Customers-Deferral of the Effective Date (Topic 606) issued by the FASB in August 2015, will be effective for annual periods (including interim periods) beginning after December 15, 2017. The Company has commenced its assessment of these new standards, developed a project plan to guide the implementation, and is evaluating the impact these new standards will have on its consolidated financial statements. The standard can be applied either retrospectively to each period presented or as a cumulative effect adjustment as of the date of adoption . The Company plans to implement these standards effective January 1, 2018 and anticipates adopting based on the modified retrospective method. In January 2016, the FASB issued ASU No. 2016-01, Financial Instruments Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities, which addresses certain aspects of recognition, measurement, presentation, and disclosure of financial instruments, including a provision that requires equity investments (except for investments accounted for under the equity method of accounting) to be measured at fair value, with changes in fair value recognized in current earnings. The ASU is effective for the Company in the first quarter of 2018, with early adoption permitted. The Company is currently evaluating the effect this ASU will have on its consolidated financial statements and related disclosures. In February 2016, the FASB issued ASU No. 2016-02, Leases (Topic 842). The update is aimed at making leasing activities more transparent and comparable, and requires substantially all leases be recognized by lessees on their balance sheet as a right-of-use asset and corresponding lease liability, including leases currently accounted for as operating leases. This guidance will become effective for interim and annual reporting periods beginning with the year ending December 31, 2019. The standard requires the use of a modified retrospective transition approach for existing leases. Early adoption is permitted. The Company is currently evaluating the effect this ASU will have on its consolidated financial statements and related disclosures. In March 2016, the FASB issued ASU No. 2016-09, Stock Compensation (Topic 718); Improvements to Employee Share-Based Payment Accounting. The new guidance simplifies several aspects of the accounting for share-based payment transactions including the income tax consequences, classification of awards as either equity or liabilities, policy election to account for forfeitures as they occur rather than on an estimated basis and classification on the statement of cash flows. The ASU is effective for annual periods beginning after December 15, 2016, including interim periods within that annual period. Early adoption is permitted. The Company elected to early adopt this ASU and has elected to account for forfeitures as they occur. In June 2016, the FASB issued ASU 2016-13, Financial Instruments-Credit Losses: Measurement of Credit Losses on Financial Instruments. ASU 2016-13 replaces the incurred loss impairment methodology in current U.S. GAAP with a methodology that reflects expected credit losses. The update is intended to provide financial statement users with more decision-useful information about the expected credit losses on financial instruments and other commitments to extend credit held by a reporting entity at each reporting date. The standard will be effective for annual reporting periods beginning after December 15, 2019, including interim periods within those reporting periods. Early adoption is permitted. The Company has not yet evaluated the effect this ASU will have on its consolidated financial statements and related disclosures. In August 2016, the FASB issued ASU No. 2016-15, Statement of Cash Flows (Topic 230). The standard clarifies the way certain cash receipts and cash payments are classified with the objective of reducing the existing diversity in practice. The standard is effective for fiscal years and interim periods beginning after December 15, 2017. Early adoption is permitted for all periods beginning after December 15, 2016. The Company is currently evaluating the effect this ASU will have on its consolidated financial statements and related disclosures. In December 2016, the FASB issued ASU 2016-19, Technical Corrections and Improvements, which clarifies and removes inconsistencies in key areas of U.S. GAAP and is effective immediately. The Company adopted this guidance in December 2016 and there was no impact on its consolidated financial statements.

Overview and Basis of Present26

Overview and Basis of Presentation (Tables)	12 Months Ended
	Dec. 31, 2016
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Major Components of Statements of Operations Data Comprising Income (Loss) from Discontinued Operations	The major components of statements of operations data comprising the income (loss) from discontinued operations are as follows: Year Ended December 31, 2016 2015 2014 (in thousands) Operating expenses: Research and development $ 350 $ 2,217 $ 3,013 General and administrative 9 1,112 280 Total operating expenses 359 3,329 3,293 Operating Income (loss) (359 ) (3,329 ) (3,293 ) Other income 400 — — Income (loss) $ 41 $ (3,329 ) $ (3,293 )

Summary of Significant Accoun27

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2016
Accounting Policies [Abstract]
Roll-Forward of Activity in Allowance for Doubtful Accounts	A roll-forward of the activity in the Company’s allowance for doubtful accounts is as follows: December 31, 2016 2015 2014 (in thousands) Allowance for doubtful accounts at beginning of year $ 75 $ 27 $ — Bad debt expense 103 48 33 Deductions (27 ) — (6 ) Allowance for doubtful accounts at end of year $ 151 $ 75 $ 27
Schedules of Concentration of Credit Risk	For the year ended December 31, 2016, four customers comprised more than 10% of total accounts receivable as follows: December 31, 2016 2015 2014 Customer A 12% * * Customer B 12% 10% 10% Customer C 11% * * Customer D 11% * * * Less than 10%

Marketable Securities (Tables)

Marketable Securities (Tables)	12 Months Ended
	Dec. 31, 2016
Investments Debt And Equity Securities [Abstract]
Summary of Marketable Securities	The Company’s marketable securities consisted of the following: December 31, 2016 Amortized Cost Basis Unrealized Gains Unrealized Losses Aggregate Fair Value (in thousands) Marketable securities: Money market accounts $ 1,580 $ — $ — $ 1,580 Corporate debt securities 38,728 3 (163 ) 38,568 Less: Cash equivalents (1,580 ) — — (1,580 ) Total marketable securities $ 38,728 $ 3 $ (163 ) $ 38,568

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2016
Fair Value Disclosures [Abstract]
Information about Financial Assets Measured at Fair Value on Recurring Basis Based on Three-Tier Fair Value Hierarchy	The following table presents information about our financial assets measured at fair value on a recurring basis as of December 31, 2016, based on the three-tier fair value hierarchy: Fair Value Measurements at December 31, 2016 Total Level 1 Level 2 Level 3 (in thousands) Marketable securities: Corporate debt securities $ 38,568 $ — $ 38,568 $ — Money market accounts 1,580 1,580 — — Total marketable securities $ 40,148 $ 1,580 $ 38,568 $ —

Fixed Assets (Tables)

Fixed Assets (Tables)	12 Months Ended
	Dec. 31, 2016
Property Plant And Equipment [Abstract]
Major Classes of Fixed Assets	Major classes of fixed assets consisted of the following: December 31, Useful Lives 2016 2015 (in thousands) Computer hardware 3 Years $ 1,293 $ 601 Computer software 3 Years 354 176 Machinery and equipment 5 Years 177 210 Medical lab equipment 5 Years 4,678 2,016 General equipment 3 Years 59 59 Furniture and fixtures 5 Years 86 51 Leasehold improvements Shorter of lease term or estimated useful life 520 256 Assets not yet placed in service 1,114 — Total 8,281 3,369 Less: Accumulated depreciation (2,047 ) (900 ) Property and equipment, net $ 6,234 $ 2,469

Other Current Assets (Tables)

Other Current Assets (Tables)	12 Months Ended
	Dec. 31, 2016
Deferred Costs Capitalized Prepaid And Other Assets Disclosure [Abstract]
Schedule of Other Current Assets	Other current assets consisted of the following: December 31, 2016 2015 (in thousands) Reagents $ 322 $ 212 Prepaid expenses 375 65 Marketable securities interest receivable 209 — Payroll tax refund — 37 Total $ 906 $ 314

Reporting Segment and Geograp32

Reporting Segment and Geographic Information (Tables)	12 Months Ended
	Dec. 31, 2016
Segment Reporting [Abstract]
Summary of Revenue by Geographic Region	Revenue by region was as follows: Year Ended December 31, 2016 2015 2014 (in thousands) Revenue: United States $ 8,258 $ 5,084 $ 640 Foreign: Canada 3,798 2,658 194 China 3,241 — — Other Countries 2,979 1,834 444 Total $ 18,276 $ 9,576 $ 1,278

Commitment and Contingencies (T

Commitment and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2016
Commitments And Contingencies Disclosure [Abstract]
Future Minimum Payments under Non-Cancelable Operating Leases	Future minimum payments under non-cancelable operating leases as of December 31, 2016 are as follows: Minimum Payments Year ending December 31, (in thousands) 2017 $ 252 2018 80 2019 — 2020 — Thereafter — Total minimum lease payments $ 332

Stockholders__Members_ Equity (

Stockholders’/Members’ Equity (Tables)	12 Months Ended
	Dec. 31, 2016
Equity [Abstract]
Summary of Units of Fulgent LLC Cancelled in Exchange for Shares of Common Stock	The following is a summary of the units of Fulgent LLC that were cancelled in exchange for shares of the Company’s common stock: Pre-Reorganization (in thousands) Class D-1 preferred units 51,382 Class D-2 preferred units 15,395 Class D common units 2,500 Class D common units — profit interests 28,355 Total 97,632

Equity-Based Compensation (Tabl

Equity-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2016
Summary of Equity-Based Compensation	The Company has included equity-based compensation expense as part of cost of revenue and operating expenses in the accompanying consolidated statements of operations as follows: Year Ended December 31, 2016 2015 (in thousands) Cost of revenue $ 754 $ 1,673 Research and development 1,161 3,241 Selling and marketing 454 1,569 General and administrative 2,285 1,673 Total $ 4,654 $ 8,156
Summary of Activity for Options to Acquire Common Shares	The following table summarizes activity for options to acquire shares of the Company’s common stock in the years ended December 31, 2016 and 2015: Shares Available for Grant (in thousands) Number of Shares Subject to Options (in thousands) Weighted- Average Exercise Price Weighted- Average Remaining Contractual Life (in years) Aggregate Intrinsic Value (in thousands) Balance at December 31, 2014 — — — — — Authorized 1,974 Granted (274 ) 274 $ 0.38 Exercised — — — Canceled — — — Balance at December 31, 2015 1,700 274 $ 0.38 9.8 $ 645 Authorized 64 Granted (324 ) 324 $ 1.18 Exercised — — — Canceled 42 (42 ) $ 0.38 Balance at December 31, 2016 1,482 556 $ 0.85 9.0 $ 5,976 Exercisable as of December 31, 2016 103 $ 0.38 8.8 $ 1,149
Summary of Grants of Share Awards and Grants of Restricted Stock Units	The following table shows grants of share awards and grants of restricted stock units during the years ended December 31, 2016 and 2015: Year Ended December 31, 2016 2015 Employee Non-Employee Employee Non-Employee (in thousands) Share Awards 329 — 3,421 — Restricted Stock Units 364 — — —
Summary of Activity for RSUs Relating to Shares of Company's Common Stock	The following table summarizes activity for RSUs relating to shares of the Company’s common stock in the year ended December 31, 2016: Number of Shares (in thousands) Weighted-Average Grant-Date Fair Value Balance at December 31, 2015 — — Granted 364 $ 9.69 Vested and settled — — Forfeited (2 ) $ 9.02 Balance at December 31, 2016 362 $ 9.69
Summary of Grants of Unit Awards Subject to Profits Interest Thresholds	The following tables show grants of Class P unit awards, all of which were subject to profits interest thresholds, during the year ended December 31, 2015: Employee Non-Employee (in thousands) Profits Interests 4,500 1,500
Summary of Weighted-Average Assumptions Used to Estimate Fair Value of Options to Acquire Shares of Company's Common Stock	The following table sets forth weighted-average assumptions used to estimate the fair value of options to acquire shares of the Company’s common stock (or, prior to the Reorganization, options to acquire common units) granted to employees during the years ended December 31, 2016 and 2015: Year Ended December 31, 2016 2015 Expected term (in years) 6.1 6.1 Risk-free interest rates 1.4 % 1.6 % Dividend yield — — Expected volatility 95.6 % 86.0 %
Summary of Weighted-Average Assumptions Used to Estimate Fair Value of Options to Acquire Common Stock Granted to Non-Employees	The following table sets forth the weighted-average assumptions used to estimate the fair value of options to acquire shares of the Company’s common stock (or, prior to the Reorganization, options to acquire common units) granted to non-employees during the years ended December 31, 2016 and 2015: Year Ended December 31, 2016 2015 Expected term (in years) 10 10 Risk-free interest rates 1.6 % 2.3 % Dividend yield — — Expected volatility 96.9 % 94.8 %
Class P Common Units
Summary of Activity for Options to Acquire Common Shares	The following table summarizes activity for options to acquire Class P common units in the year ended December 31, 2015: Number of Units Subject to Options (in thousands) Weighted- Average Exercise Price Per Unit Weighted- Average Remaining Contractual Life (in years) Aggregate Intrinsic Value Outstanding as of December 31, 2014 — — — — Granted 1,810 $ 0.04 9.8 $ — Exercised — $ — Forfeited/canceled — $ — Outstanding as of December 31, 2015 1,810 $ 0.04 9.8 $ — Vested and expected to vest as of December 31, 2015 1,810 $ 0.04 9.8 $ —
Summary of Weighted-Average Assumptions Used to Estimate Fair Value of Options to Acquire Common Stock Granted to Non-Employees	The following table sets forth the weighted-average assumptions used to estimate the fair value of options to acquire Class P common units granted to non-employees during the year ended December 31, 2015: Year Ended December 31, 2015 Expected term (in years) 10 Risk-free interest rates 2.3 % Dividend yield — Expected volatility 98.0 %
Class D and Class P Common Unit - Profit Interest
Summary of Weighted-Average Assumptions Used to Estimate Fair Value of Units Awards Subject to Profits Interest Thresholds	The following table sets forth weighted-average assumptions used to estimate the fair value of Class D and Class P common unit awards subject to profits interest thresholds granted to employees and non-employees during the year ended December 31, 2015 (no such Class D awards were granted to non-employees during such period and no such awards were granted to employees or non-employees during the year ended December 31, 2016): Class D Class P Employee: Expected term (in years) 2 2 Risk-free interest rates 0.6 % 0.6 % Dividend yield 0 0 Expected volatility 68.1 % 75.8 % Non—Employee: Expected term (in years) * 2 Risk-free interest rates * 0.6 % Dividend yield * 0 Expected volatility * 75.6 % * No awards granted

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Income Tax Expense	Income tax expense consisted of the following: Year Ended December 31, 2016 (in thousands) Current: Federal $ 616 State 58 Total Current 674 Deferred: Federal 295 State (49 ) Change in valuation allowance — Total Deferred 246 Total income tax expense $ 920
Reconciliation of Difference between Federal Statutory Income Tax Rate and Effective Income Tax Rate	Reconciliation of the difference between the federal statutory income tax rate and the effective income tax rate for the year ended December 31, 2016 is as follows: Year Ended December 31, 2016 Tax provision at federal statutory rate 34.00 % State franchise tax, net of federal income tax benefit 1.98 % Other 0.16 % LLC income not subject to corporate taxes -37.23 % Recognition of pre-merger temporary differences -19.51 % Tax provision -20.60 %
Summary of Elements of Deferred Tax Assets (Liabilities)	The following table summarizes the elements of the deferred tax assets (liabilities) at December 31, 2016: Year Ended December 31, 2016 (in thousands) Deferred tax assets Accrued vacation and other accrued expenses $ 69 Provision for bad debts 54 Equity-based compensation 603 Unrealized loss on investments 58 State income taxes 20 Total deferred tax assets $ 804 Deferred tax liabilities Depreciation $ 993 Total deferred tax liabilities 993 Net deferred tax liabilities $ (189 )

Income (Loss) Per Share (Tables

Income (Loss) Per Share (Tables)	12 Months Ended
	Dec. 31, 2016
Earnings Per Share [Abstract]
Reconciliation of Denominator of the Basic and Diluted (Loss) Per Share Computations	Income (loss) per share for the years ended December 31, 2016 and 2015 was computed as if the Reorganization, including the issuance of one share of common stock in exchange for the cancellation of every 7.6 Class D common and preferred units of Fulgent LLC, had occurred subsequent to the Recapitalization, which occurred in October 2015, with the exception of Class P units which are not subject to the effect of the Reorganization. Income (loss) per share prior to the Recapitalization in October 2015 is not presented. The following is a reconciliation of the denominators of the basic and diluted (loss) per share computations: Years Ended 2016 2015 Continuing Operations Discontinued Operations Total Continuing Operations Discontinued Operations Total (in thousands, except per share data) Loss for the period from October 16, 2015 through December 31, 2015 — — — $ (7,239 ) $ (896 ) $ (8,135 ) Income (loss) $ (5,388 ) $ 41 $ (5,347 ) $ (7,239 ) $ (896 ) $ (8,135 ) Deemed dividend on redemption of Class D-1 preferred unit $ (3,727 ) — $ (3,727 ) — — $ 0 Distribution to Class D-1 preferred unitholder $ (4,592 ) — $ (4,592 ) — — $ 0 Income (loss) allocable to common shareholders $ (13,707 ) $ 41 $ (13,666 ) $ (7,239 ) $ (896 ) $ (8,135 ) Income (loss) allocated to common shareholders $ (13,707 ) $ (7,239 ) Income (loss) allocated to Class P common units — $ 18 — $ (896 ) Income (loss) allocated to Class P preferred units — $ 23 — — Weighted-average common shares—outstanding, basic and diluted 13,710 — 11,842 — Weighted-average Class P common units - profit interests - outstanding, basic and diluted — 10,123 — 5,796 Weighted-average Class P preferred units outstanding, basic and diluted — 13,238 — — Income (loss) per common share from continuing operations, basic and diluted $ (1.00 ) — $ (0.61 ) — Income per Class P common unit - profit interests, basic and diluted — — — $ (0.15 ) Income per Class P preferred unit, basic and diluted — — — —
Anti-dilutive Securities Excluded from Calculation of Diluted Income (Loss) Per Share	The following securities have been excluded from the calculation of diluted income (loss) per share for all periods presented because their effect would have been anti-dilutive: Years Ended 2016 2015 Continuing Operations Discontinued Operations Continuing Operations Discontinued Operations (in thousands) Options 490 — 274 — RSUs 79 — — — Class P unit options — — — 1,810

Selected Quarterly Financial 38

Selected Quarterly Financial Data (Unaudited) (Tables)	12 Months Ended
	Dec. 31, 2016
Quarterly Financial Information Disclosure [Abstract]
Unaudited Quarterly Data	Three Months Ended Dec. 31, 2016 Sept. 30, 2016 June 30, 2016 Mar. 31, 2016 Dec. 31, 2015 Sept. 30, 2015 June 30, 2015 Mar. 31, 2015 (in thousands) Statement of Operations Data: Revenue $ 5,854 $ 5,011 $ 3,971 $ 3,440 $ 2,901 $ 2,905 $ 2,182 $ 1,588 Cost of revenue 1,863 2,143 1,411 1,304 2,726 918 772 653 Gross profit 3,991 2,868 2,560 2,136 175 1,987 1,410 935 Operating expenses: Research and development 818 1,523 656 561 3,650 312 252 217 Selling and marketing 798 893 477 301 1,913 280 243 234 General and administrative 1,116 1,147 457 1,889 1,956 215 168 79 Total operating expenses 2,732 3,563 1,590 2,751 7,519 807 663 530 Operating income (loss) 1,259 (695 ) 970 (615 ) (7,344 ) 1,180 747 405 Interest and other income (expense) 57 5 (5,462 ) 13 7 - - 20 Income (loss) before income taxes 1,316 (690 ) (4,492 ) (602 ) (7,337 ) 1,180 747 425 Provision for income taxes 503 417 - - - - - - Net income (loss) $ 813 $ (1,107 ) $ (4,492 ) $ (602 ) $ (7,337 ) $ 1,180 $ 747 $ 425 Net income (loss) per common share: Basic $ 0.05 $ (0.44 ) $ (5.49 ) $ (0.02 ) $ (0.61 ) * * * Diluted $ 0.05 $ (0.44 ) $ (5.49 ) $ (0.02 ) $ (0.61 ) * * * *Basic and diluted income (loss) per common share was calculated prospectively from the date the Class D common units were issued in the Recapitalization in October 2015 . See Note 1, Overview and Basis of Presentation, and Note 12, Income (Loss) per Share, to these consolidated financial statements for additional information.

Overview and Basis of Present39

Overview and Basis of Presentation - Additional Information (Details) - USD ($)	Oct. 07, 2016	Oct. 04, 2016	Oct. 16, 2015	Sep. 30, 2016	Dec. 31, 2016	Dec. 31, 2015
Description Of Business And Basis Of Presentation [Line Items]
Place of incorporation					Delaware
Date of incorporation					May 13, 2016
Date of corporate name change					Aug. 2, 2016
Common Stock | IPO
Description Of Business And Basis Of Presentation [Line Items]
Stock issued and sold (in shares)		4,830,000
Stock price per share		$ 9
Proceeds from issuance of shares		$ 36,000,000
Underwriting discounts and commissions		3,000,000
Other offering expenses		$ 4,400,000
Common Stock | Over Allotment Option
Description Of Business And Basis Of Presentation [Line Items]
Stock issued and sold (in shares)	630,000
Class A and Class B Units
Description Of Business And Basis Of Presentation [Line Items]
Deemed distributions			$ 34,500,000
Restricted Stock Units (RSUs)
Description Of Business And Basis Of Presentation [Line Items]
Units cancelled in exchange for restricted stock units relating to company’s common stock					364,000	0
Fulgent Therapeutics LLC
Description Of Business And Basis Of Presentation [Line Items]
Ownership percentage in subsidiary					100.00%
Units cancelled in exchange for one share of common stock				7.6	7.6	7.6
Share of common stock exchanged for seven point six units				1	1	1
Gain (loss) on reorganization					$ 0
Fulgent Therapeutics LLC | Maximum
Description Of Business And Basis Of Presentation [Line Items]
Options to acquire units cancelled in exchange for company’s common stock					591,112
Fulgent Therapeutics LLC | Restricted Stock Units (RSUs)
Description Of Business And Basis Of Presentation [Line Items]
Units cancelled in exchange for restricted stock units relating to company’s common stock					65,789
Fulgent Therapeutics LLC | Class D-1 Preferred Units
Description Of Business And Basis Of Presentation [Line Items]
Number of common stock shares exchanged for cancelled units					6,760,733
Fulgent Therapeutics LLC | Class D-2 Preferred Units
Description Of Business And Basis Of Presentation [Line Items]
Number of common stock shares exchanged for cancelled units					2,025,623
Fulgent Therapeutics LLC | Class D Common Units
Description Of Business And Basis Of Presentation [Line Items]
Number of common stock shares exchanged for cancelled units					4,059,900

Overview and Basis of Present40

Overview and Basis of Presentation - Major Components of Statements of Operations Data Comprising Income (Loss) from Discontinued Operations (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Operating expenses:
Research and development	$ 350	$ 2,217	$ 3,013
General and administrative	9	1,112	280
Total operating expenses	359	3,329	3,293
Operating Income (loss)	(359)	(3,329)	(3,293)
Other income	400
Income (loss)	$ 41	$ (3,329)	$ (3,293)

Summary of Significant Accoun41

Summary of Significant Accounting Policies - Roll-Forward of Activity in Allowance for Doubtful Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Receivables [Abstract]
Allowance for doubtful accounts at beginning of year	$ 75	$ 27
Bad debt expense	103	48	$ 33
Deductions	(27)		(6)
Allowance for doubtful accounts at end of year	$ 151	$ 75	$ 27

Summary of Significant Accoun42

Summary of Significant Accounting Policies - Additional Information (Detail)	Sep. 30, 2016USD ($)	Dec. 31, 2016USD ($)CustomerSegment	Dec. 31, 2015USD ($)	Dec. 31, 2014
Summary Of Significant Accounting Policies [Line Items]
Impairment losses of long-lived assets		$ 0
Number of reporting segments | Segment		1
Shipping and handling fees incurred		$ 0
Federal and state tax expense (benefit) prior to reorganization.		0
Equity-based compensation expense		$ 4,654,000	$ 8,156,000
Class D Common Units
Summary Of Significant Accounting Policies [Line Items]
Conversion ratio		0.1316
Options
Summary Of Significant Accounting Policies [Line Items]
Equity-based compensation options contractual term		10 years
Equity-based compensation expense	$ 0
Computer Software
Summary Of Significant Accounting Policies [Line Items]
Estimated useful lives of fixed assets		3 years
Minimum
Summary Of Significant Accounting Policies [Line Items]
Estimated useful lives of fixed assets		3 years
Maximum
Summary Of Significant Accounting Policies [Line Items]
Estimated useful lives of fixed assets		5 years
Maximum | Options
Summary Of Significant Accounting Policies [Line Items]
Equity-based compensation, options vesting period		4 years
Accounts Receivable | Customer Concentration Risk
Summary Of Significant Accounting Policies [Line Items]
Number of customers comprised more than 10% of total accounts receivable or revenues | Customer		4
Accounts Receivable | Customer Concentration Risk | Customer A
Summary Of Significant Accounting Policies [Line Items]
Concentration risk, percentage		12.00%
Accounts Receivable | Customer Concentration Risk | Customer B
Summary Of Significant Accounting Policies [Line Items]
Concentration risk, percentage		12.00%	10.00%	10.00%
Revenues | Customer Concentration Risk | Customer A
Summary Of Significant Accounting Policies [Line Items]
Concentration risk, percentage		15.00%
Revenues | Customer Concentration Risk | Customer B
Summary Of Significant Accounting Policies [Line Items]
Concentration risk, percentage		15.00%	19.00%	11.00%

Summary of Significant Accoun43

Summary of Significant Accounting Policies - Concentration of Credit Risk (Detail) - Accounts Receivable - Customer Concentration Risk	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Customer A
Concentration Risk [Line Items]
Concentration risk, percentage	12.00%
Customer B
Concentration Risk [Line Items]
Concentration risk, percentage	12.00%	10.00%	10.00%
Customer C
Concentration Risk [Line Items]
Concentration risk, percentage	11.00%
Customer D
Concentration Risk [Line Items]
Concentration risk, percentage	11.00%

Marketable Securities - Summary

Marketable Securities - Summary of Marketable Securities (Details) - USD ($)	Dec. 31, 2016	Dec. 31, 2015
Schedule of Available For Sale Securities [Line Items]
Marketable securities, Amortized Cost Basis	$ 38,728,000
Marketable securities, Unrealized Gains	3,000
Marketable securities, Unrealized Loses	(163,000)
Marketable securities, Aggregate Fair Value	38,568,000	$ 0
Less: Cash equivalents	(1,580,000)
Money Market Accounts
Schedule of Available For Sale Securities [Line Items]
Marketable securities, Amortized Cost Basis	1,580,000
Marketable securities, Aggregate Fair Value	1,580,000
Corporate Debt Securities
Schedule of Available For Sale Securities [Line Items]
Marketable securities, Amortized Cost Basis	38,728,000
Marketable securities, Unrealized Gains	3,000
Marketable securities, Unrealized Loses	(163,000)
Marketable securities, Aggregate Fair Value	$ 38,568,000

Marketable Securities - Additio

Marketable Securities - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Investments Debt And Equity Securities [Abstract]
Marketable securities	$ 38,568,000	$ 0
Marketable securities less than one year	12,971,000
Marketable securities greater than one year and less than five years	25,597,000
Gross unrealized loss	163,000
Sales of marketable securities	$ 0

Fair Value Measurements - Infor

Fair Value Measurements - Information about Financial Assets Measured at Fair Value on Recurring Basis Based on Three-Tier Fair Value Hierarchy (Details) - Fair Value Measurements Recurring $ in Thousands	Dec. 31, 2016USD ($)
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total marketable securities	$ 40,148
Corporate Debt Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total marketable securities	38,568
Money Market Accounts
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total marketable securities	1,580
Level 1
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total marketable securities	1,580
Level 1 | Money Market Accounts
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total marketable securities	1,580
Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total marketable securities	38,568
Level 2 | Corporate Debt Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total marketable securities	$ 38,568

Fair Value Measurements - Addit

Fair Value Measurements - Additional Information (Details)	Dec. 31, 2016USD ($)
Fair Value Disclosures [Abstract]
Fair value asset, investments measured using unobservable inputs	$ 0
Fair value assets, transfers between levels, amount	0
Securities in an unrealized loss position for more than 12 months	$ 0

Fixed Assets - Major Classes of

Fixed Assets - Major Classes of Fixed Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Property Plant And Equipment [Line Items]
Fixed assets, gross	$ 8,281	$ 3,369
Less: Accumulated depreciation	(2,047)	(900)
Fixed assets, net	6,234	2,469
Computer Hardware
Property Plant And Equipment [Line Items]
Fixed assets, gross	$ 1,293	601
Useful life in years	3 years
Computer Software
Property Plant And Equipment [Line Items]
Fixed assets, gross	$ 354	176
Useful life in years	3 years
Machinery and Equipment
Property Plant And Equipment [Line Items]
Fixed assets, gross	$ 177	210
Useful life in years	5 years
Medical Lab Equipment
Property Plant And Equipment [Line Items]
Fixed assets, gross	$ 4,678	2,016
Useful life in years	5 years
General Equipment
Property Plant And Equipment [Line Items]
Fixed assets, gross	$ 59	59
Useful life in years	3 years
Furniture and Fixtures
Property Plant And Equipment [Line Items]
Fixed assets, gross	$ 86	51
Useful life in years	5 years
Leasehold Improvements
Property Plant And Equipment [Line Items]
Fixed assets, gross	$ 520	$ 256
Useful life in years	Shorter of lease term or estimated useful life
Assets Not Yet Placed in Service
Property Plant And Equipment [Line Items]
Fixed assets, gross	$ 1,114

Fixed Assets - Additional Infor

Fixed Assets - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Property Plant And Equipment [Line Items]
Depreciation expense on fixed assets	$ 1,170,000	$ 575,000	$ 196,000
Fixed Assets
Property Plant And Equipment [Line Items]
Depreciation expense on fixed assets	$ 1,200,000	$ 575,000	$ 196,000

Other Current Assets - Schedule

Other Current Assets - Schedule of Other Current Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Deferred Costs Capitalized Prepaid And Other Assets Disclosure [Abstract]
Reagents	$ 322	$ 212
Prepaid expenses	375	65
Marketable securities interest receivable	209
Payroll tax refund		37
Total	$ 906	$ 314

Reporting Segment and Geograp51

Reporting Segment and Geographical Information - Additional Information (Details)	12 Months Ended
	Dec. 31, 2016Segment
Segment Reporting [Abstract]
Number of reporting segments	1

Reporting Segment and Geograp52

Reporting Segment and Geographical Information - Summary of Revenue by Geographic Region (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Segment Reporting Information [Line Items]
Revenue	$ 5,854	$ 5,011	$ 3,971	$ 3,440	$ 2,901	$ 2,905	$ 2,182	$ 1,588	$ 18,276	$ 9,576	$ 1,278
United States
Segment Reporting Information [Line Items]
Revenue									8,258	5,084	640
Canada
Segment Reporting Information [Line Items]
Revenue									3,798	2,658	194
China
Segment Reporting Information [Line Items]
Revenue									3,241
Other Countries
Segment Reporting Information [Line Items]
Revenue									$ 2,979	$ 1,834	$ 444

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Commitments And Contingencies [Line Items]
Operating leases, rent expense	$ 204,000	$ 158,000	$ 64,000
Reagents and Equipment
Commitments And Contingencies [Line Items]
Purchase obligations	$ 2,200,000
Minimum | Non Cancelable Operating Lease
Commitments And Contingencies [Line Items]
Operating leases, renewal term	2 years
Maximum | Non Cancelable Operating Lease
Commitments And Contingencies [Line Items]
Operating leases, renewal term	3 years

Commitments and Contingencies54

Commitments and Contingencies - Future Minimum Payments under Non-Cancelable Operating Leases (Details) $ in Thousands	Dec. 31, 2016USD ($)
Commitments And Contingencies Disclosure [Abstract]
2,017	$ 252
2,018	80
Total minimum lease payments	$ 332

Stockholders' _ Members' Equity

Stockholders' / Members' Equity - Additional Information (Details)	May 17, 2016USD ($)shares	May 13, 2016USD ($)shares	May 31, 2016USD ($)shares	Sep. 30, 2016USD ($)shares	Dec. 31, 2016USD ($)Vote$ / sharesshares	Dec. 31, 2015USD ($)shares
Class Of Stock [Line Items]
Aggregate purchase price					$ 26,980,000
Common stock, shares authorized | shares					200,000,000
Common stock, par value | $ / shares					$ 0.0001
Preferred stock, shares authorized | shares					1,000,000
Preferred stock, par value | $ / shares					$ 0.0001
Preferred stock, shares outstanding | shares					0
Tax distribution to former LLC members					$ 1,300,000
Return of capital contribution					$ 4,600,000
Distributions made						$ 0
Reorganization | Common Stock
Class Of Stock [Line Items]
Cancelled in exchange for common units | shares					12,846,256
Reorganization | Common Stock and Additional Paid-in Capital
Class Of Stock [Line Items]
Conversion of members' interests				$ 72,000,000
Class D-1 Preferred Units
Class Of Stock [Line Items]
Deemed dividend					$ 3,727,000
Class D-2 Preferred Units
Class Of Stock [Line Items]
Issuance costs of units					$ 185,000
Xi Long Financing
Class Of Stock [Line Items]
Aggregate purchase price		$ 12,000,000
Xi Long Financing | Class D-1 Preferred Units
Class Of Stock [Line Items]
Number of units acquired | shares		4,618,421
Deemed dividend			$ 3,700,000
Xi Long Financing | Class D Common Units
Class Of Stock [Line Items]
Number of units acquired | shares		5,644,737
Xi Long Financing | Class D-2 Preferred Units
Class Of Stock [Line Items]
Number of units acquired | shares	5,131,579
Aggregate purchase price	$ 15,200,000
Issuance costs of units			185,000
Net proceeds from issuance of units			$ 15,000,000
Conversion of stock, shares converted | shares			2,025,623
Issuance of preferred units, shares | shares			15,394,737
Issuance of preferred units, value			$ 32,600,000
Aggregate purchase price			27,200,000
Difference amount of fair value and aggregate consideration paid			$ 5,500,000
Fulgent Therapeutics LLC
Class Of Stock [Line Items]
Units cancelled in exchange for one share of common stock | shares				7.6	7.6	7.6
Share of common stock exchanged for seven point six units | shares				1	1	1
Certificate of Incorporation
Class Of Stock [Line Items]
Common stock, shares authorized | shares					200,000,000
Common stock, par value | $ / shares					$ 0.0001
Preferred stock, shares authorized | shares					1,000,000
Preferred stock, par value | $ / shares					$ 0.0001
Preferred stock, shares outstanding | shares					0
Certificate of Incorporation | Common Stock
Class Of Stock [Line Items]
Number of vote per share held | Vote					1

Stockholders' _ Members' Equi56

Stockholders' / Members' Equity - Summary of Units of Fulgent LLC Cancelled in Exchange for Shares of Common Stock (Details)	12 Months Ended
	Dec. 31, 2016shares
Class Of Stock [Line Items]
Pre-Reorganization	97,632,000
Class D-1 Preferred Units
Class Of Stock [Line Items]
Pre-Reorganization	51,382,000
Class D-2 Preferred Units
Class Of Stock [Line Items]
Pre-Reorganization	15,395,000
Class D Common Units
Class Of Stock [Line Items]
Pre-Reorganization	2,500,000
Class D Common Units - Profit Interests
Class Of Stock [Line Items]
Pre-Reorganization	28,355,000

Equity-Based Compensation - Add

Equity-Based Compensation - Additional Information (Details)	Sep. 30, 2016USD ($)	Dec. 31, 2016USD ($)$ / sharesshares	Dec. 31, 2015USD ($)$ / sharesshares	Dec. 31, 2014shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Equity-based compensation expense | $		$ 4,654,000	$ 8,156,000
Weighted-Average Exercise Price Per Units/Shares, Granted | $ / shares		$ 1.18	$ 0.38
Participation threshold for awards granted | $ / shares			$ 0.3617
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Number | shares			2,105,263
Initial public offerings completion date		Oct. 4, 2016
Class P Common Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-Average Exercise Price Per Units/Shares, Granted | $ / shares			$ 0.04
Class D Common Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Discount for lack of marketability			35.00%
Class D Common Units | Gordon Growth Analysis
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted percentage of valuation technique			50.00%
Class D Common Units | Guideline Public Company Method
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted percentage of valuation technique			50.00%
Fulgent Therapeutics LLC
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Equity-based compensation expense | $		$ 1,400,000
Cancellation of common stock ratio		0.1316
Fulgent Therapeutics LLC | Discontinued Operations
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Equity-based compensation expense | $		$ 0	$ 120,000
Xi Long Financing | Class D Common Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Discount for lack of marketability			20.00%
Class D Common Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Cancellation of common stock ratio		0.1316
Non-Employee | Class P Common Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Units granted | shares		0
2015 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period		4 years
Equity-based compensation options contractual term		10 years
Equity-based compensation expense | $		$ 0
2015 Equity Incentive Plan | Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Equity-based compensation expense | $		$ 1,100,000
2016 Omnibus Incentive Plan | Class D Common Units | Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Cancellation of common stock ratio		0.1316
2016 Omnibus Incentive Plan | Employees Directors and Consultants | Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares available for issuance under the plan | shares		2,038,480
Restricted Stock Units (RSUs)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period		4 years
Equity-based compensation expense | $		$ 192,000
Expected to be recognized, weighted-average period		3 years 9 months 18 days
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Number | shares		362,000
Total compensation cost not yet recognized on grant date | $		$ 3,500,000
Compensation cost not yet recognized on grant date, period for recognition		4 years
Unrecognized compensation expense | $		$ 3,300,000
Units granted | shares		364,000	0
Weighted-average grant date fair value, granted | $ / shares		$ 9.69
Restricted Stock Units (RSUs) | Fulgent Therapeutics LLC
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Units granted | shares		65,789
Restricted Stock Units (RSUs) | 2015 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period		4 years
Restricted Stock Units (RSUs) | 2016 Omnibus Incentive Plan | Class D Common Units | Fulgent Therapeutics LLC
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Cancellation of common stock ratio		0.1316
Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Equity-based compensation options contractual term		10 years
Equity-based compensation expense | $	$ 0
Weighted-Average Exercise Price Per Units/Shares, Granted | $ / shares		$ 7.94	$ 2.51
Unrecognized compensation expense | $		$ 1,600,000
Expected to be recognized, weighted-average period		2 years 10 months 24 days
Options | Fulgent Therapeutics LLC | Class P Common Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized compensation expense | $			$ 64,000
Weighted average grant date fair value of options | $ / shares			$ 0.04
Options | Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period		4 years
Shares Awards
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Equity-based compensation expense | $		$ 1,600,000
Unit Awards | Class P Profit Interests
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Units granted | shares				0
Unit Awards | Fulgent Therapeutics LLC | Class P Common Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Participation threshold for awards granted | $ / shares			0.0287
Weighted-average grant date fair value, granted | $ / shares			$ 0.02
Unit Awards | Non-Employee | Class P Profit Interests
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Units granted | shares			1,500,000
Unit Awards | Non-Employee | Class D Common Units - Profit Interests
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Units granted | shares			0
Unit Awards | Non-Employee | Class D and Class P Common Unit - Profit Interest
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Units granted | shares		0
Unit Awards | Employee | Class P Profit Interests
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Units granted | shares			4,500,000
Unit Awards | Employee | Class D and Class P Common Unit - Profit Interest
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Units granted | shares		0

Equity-Based Compensation - Sum

Equity-Based Compensation - Summary of Equity-Based Compensation Expenses as Part of Cost of Revenue and Operating Expenses (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Equity-based compensation expense	$ 4,654	$ 8,156
Cost of Revenue
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Equity-based compensation expense	754	1,673
Research and Development
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Equity-based compensation expense	1,161	3,241
Selling and Marketing
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Equity-based compensation expense	454	1,569
General and Administrative
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Equity-based compensation expense	$ 2,285	$ 1,673

Equity-Based Compensation - S59

Equity-Based Compensation - Summary of Activity for Options to Acquire Common Shares (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares Available for Grant, Beginning Balance	1,700
Shares Available for Grant, Authorized	64	1,974
Shares Available for Grant, Ending Balance	1,482	1,700
Number of Units/Shares Subject to Options, Beginning Balance	274
Number of Units/Shares Subject to Options, Granted	324	274
Number of Units/Shares Subject to Options, Canceled	(42)
Number of Units/Shares Subject to Options, Ending Balance	556	274
Number of Units/Shares Subject to Options, Exercisable	103
Weighted-Average Exercise Price Per Units/Shares, Beginning Balance	$ 0.38
Weighted-Average Exercise Price Per Units/Shares, Granted	1.18	$ 0.38
Weighted-Average Exercise Price Per Units/Shares, Canceled	0.38
Weighted-Average Exercise Price Per Units/Shares, Ending Balance	0.85	$ 0.38
Weighted-Average Exercise Price Per Units/Shares, Exercisable	$ 0.38
Weighted-Average Remaining Contractual Life (in years)	9 years	9 years 9 months 18 days
Weighted-Average Remaining Contractual Life (in years), Exercisable	8 years 9 months 18 days
Aggregate Intrinsic Value, Balance	$ 5,976	$ 645
Aggregate Intrinsic Value, Exercisable	$ 1,149
Class P Common Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Units/Shares Subject to Options, Beginning Balance	1,810
Number of Units/Shares Subject to Options, Granted		1,810
Number of Units/Shares Subject to Options, Ending Balance		1,810
Number of Units/Shares Subject to Options, Vested and expected to vest		1,810
Weighted-Average Exercise Price Per Units/Shares, Beginning Balance	$ 0.04
Weighted-Average Exercise Price Per Units/Shares, Granted		$ 0.04
Weighted-Average Exercise Price Per Units/Shares, Ending Balance		0.04
Weighted-Average Exercise Price Per Units/Shares, Vested and expected to vest		$ 0.04
Weighted-Average Remaining Contractual Life (in years), Granted		9 years 9 months 18 days
Weighted-Average Remaining Contractual Life (in years)		9 years 9 months 18 days
Weighted-Average Remaining Contractual Life (in years), Vested and expected to vest		9 years 9 months 18 days

Equity-Based Compensation - S60

Equity-Based Compensation - Summary of Grants of Share Awards and Grants of Restricted Stock Units (Details) - shares	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share Awards	324,000	274,000
Share and RSU Awards | Employee
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share Awards	329,000	3,421,000
Restricted Stock Units	364,000

Equity-Based Compensation - S61

Equity-Based Compensation - Summary of Activity for RSUs Relating to Shares of Company's Common Stock (Details) - $ / shares	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Number of Shares
Number of Shares, Balance at December 31, 2015	2,105,263
Number of Shares, Balance at December 31, 2016		2,105,263
Restricted Stock Units (RSUs)
Number of Shares
Number of Shares, Granted	364,000	0
Number of Shares, Forfeited	(2,000)
Number of Shares, Balance at December 31, 2016	362,000
Weighted-Average Grant-Date Fair Value
Weighted-Average Grant-Date Fair Value, Granted	$ 9.69
Weighted-Average Grant-Date Fair Value, Forfeited	9.02
Weighted-Average Grant-Date Fair Value, Balance at December 31, 2016	$ 9.69

Equity-Based Compensation - S62

Equity-Based Compensation - Summary of Grants of Unit Awards Subject to Profits Interest Thresholds (Details) - Unit Awards - Class P Profit Interests - shares	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Units granted		0
Employee
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Units granted	4,500,000
Non-Employee
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Units granted	1,500,000

Equity-Based Compensation - S63

Equity-Based Compensation - Summary of Weighted-Average Assumptions Used to Estimate Fair Value of Options to Acquire Shares of Company's Common Stock (Details) - Options	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term (in years)	6 years 1 month 6 days	6 years 1 month 6 days
Risk-free interest rates	1.40%	1.60%
Expected volatility	95.60%	86.00%

Equity-Based Compensation - S64

Equity-Based Compensation - Summary of Weighted-Average Assumptions Used to Estimate Fair Value of Options to Acquire Common Stock Granted to Non-Employees (Details)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term (in years)	10 years	10 years
Risk-free interest rates	1.60%	2.30%
Expected volatility	96.90%	94.80%
Class P Common Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term (in years)		10 years
Risk-free interest rates		2.30%
Expected volatility		98.00%

Equity-Based Compensation - S65

Equity-Based Compensation - Summary of Weighted-Average Assumptions Used to Estimate Fair Value of Units Awards Subject to Profits Interest Thresholds (Details)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term (in years)	10 years	10 years
Risk-free interest rates	1.60%	2.30%
Expected volatility	96.90%	94.80%
Unit Awards | Employee | Class D Profit Interests
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term (in years)		2 years
Risk-free interest rates		0.60%
Dividend yield		0.00%
Expected volatility		68.10%
Unit Awards | Employee | Class P Common Units - Profit Interests
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term (in years)		2 years
Risk-free interest rates		0.60%
Dividend yield		0.00%
Expected volatility		75.80%
Unit Awards | Non-Employee | Class P Common Units - Profit Interests
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term (in years)		2 years
Risk-free interest rates		0.60%
Dividend yield		0.00%
Expected volatility		75.60%

Equity-Based Compensation - S66

Equity-Based Compensation - Summary of Weighted-Average Assumptions Used to Estimate Fair Value of Units Awards Subject to Profits Interest Thresholds (Parenthetical) (Details)	12 Months Ended
	Dec. 31, 2015shares
Unit Awards | Class D Profit Interests | Non-Employee
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Units granted	0

Income Taxes - Additional Infor

Income Taxes - Additional Information (Details) - USD ($)	3 Months Ended		12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Taxes [Line Items]
Income tax expense	$ 503,000	$ 417,000	$ 920,000	$ 0	$ 0
Net deferred tax asset	54,000		54,000
Net deferred tax liability	189,000		189,000
Interests or penalties accrued	0		0
State [Member]
Income Taxes [Line Items]
Net deferred tax asset	54,000	86,000	54,000
Federal [Member]
Income Taxes [Line Items]
Net deferred tax liability	$ 243,000	$ 503,000	$ 243,000

Income Taxes - Income Tax Expen

Income Taxes - Income Tax Expense (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Current:
Federal			$ 616
State			58
Total Current			674
Deferred:
Federal			295
State			(49)
Total Deferred			246
Total income tax expense	$ 503	$ 417	$ 920	$ 0	$ 0

Income Taxes - Reconciliation o

Income Taxes - Reconciliation of Difference between Federal Statutory Income Tax Rate and Effective Income Tax Rate (Details)	12 Months Ended
	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Tax provision at federal statutory rate	34.00%
State franchise tax, net of federal income tax benefit	1.98%
Other	0.16%
LLC income not subject to corporate taxes	(37.23%)
Recognition of pre-merger temporary differences	(19.51%)
Tax provision	(20.60%)

Income Taxes - Summary of Eleme

Income Taxes - Summary of Elements of Deferred Tax Assets (Liabilities) (Details) $ in Thousands	Dec. 31, 2016USD ($)
Deferred tax assets
Accrued vacation and other accrued expenses	$ 69
Provision for bad debts	54
Equity-based compensation	603
Unrealized loss on investments	58
State income taxes	20
Total deferred tax assets	804
Deferred tax liabilities
Depreciation	993
Total deferred tax liabilities	993
Net deferred tax liabilities	$ (189)

Income (Loss) Per Share - Addit

Income (Loss) Per Share - Additional Information (Details) - Fulgent Therapeutics LLC - shares	9 Months Ended	12 Months Ended
	Sep. 30, 2016	Dec. 31, 2016	Dec. 31, 2015
Earnings Per Share Basic And Diluted [Line Items]
Units cancelled in exchange for one share of common stock	7.6	7.6	7.6
Share of common stock exchanged for seven point six units	1	1	1

Income (Loss) Per Share - Recon

Income (Loss) Per Share - Reconciliation of Denominator of Basic and Diluted (Loss) Per Share Computations (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended									12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Earnings Per Share Basic And Diluted [Line Items]
Income (loss), continuing operations						$ (7,239)				$ (5,388)	$ (4,985)	$ (990)
Continuing operations—common stock										$ (1)	$ (0.61)	$ 0	[1]
Income (loss) from discontinued operations						(896)				$ 41	$ (3,329)	$ (3,293)
Income (loss)	$ 813	$ (1,107)	$ (4,492)	$ (602)	$ (7,337)	(8,135)	$ 1,180	$ 747	$ 425	(5,347)	$ (8,314)	$ (4,283)
Income (loss) allocable to common shareholders						(8,135)				$ (13,666)
Weighted-average common shares—outstanding—basic and diluted										13,710,000	11,842,000	0
Continuing Operations
Earnings Per Share Basic And Diluted [Line Items]
Income (loss) allocable to common shareholders						(7,239)				$ (13,707)
Income (loss) allocated to common shareholders						$ (7,239)				$ (13,707)
Weighted-average common shares—outstanding—basic and diluted						11,842				13,710
Income (loss) per common share from continuing operations, basic and diluted						$ (0.61)				$ (1)
Discontinued Operations
Earnings Per Share Basic And Diluted [Line Items]
Income (loss) allocable to common shareholders						$ (896)				$ 41
Class P Preferred Units | Discontinued Operations
Earnings Per Share Basic And Diluted [Line Items]
Income (loss) allocated to preferred units										$ 23
Weighted-average common shares—outstanding—basic and diluted										13,238
Class P Common Units | Discontinued Operations
Earnings Per Share Basic And Diluted [Line Items]
Income (loss) allocated to common units						$ (896)				$ 18
Weighted-average Class P common units - profit interests - outstanding, basic and diluted						5,796				10,123
Income per Class P common unit - profit interests, basic and diluted						$ (0.15)
Class D-1 Preferred Units
Earnings Per Share Basic And Diluted [Line Items]
Deemed dividend on redemption of Class D-1 preferred unit						$ 0				$ (3,727)
Distribution to Class D-1 preferred unitholder						$ 0				(4,592)
Class D-1 Preferred Units | Continuing Operations
Earnings Per Share Basic And Diluted [Line Items]
Deemed dividend on redemption of Class D-1 preferred unit										(3,727)
Distribution to Class D-1 preferred unitholder										$ (4,592)
[1]	Basic and diluted income (loss) per common share was calculated prospectively from the date the Class D common units were issued in the Recapitalization in October 2015. See Note 1, Overview and Basis of Presentation, and Note 12, Income (Loss) per Share, to these consolidated financial statements for additional information.

Income (Loss) Per Share - Anti-

Income (Loss) Per Share - Anti-dilutive Securities Excluded from Calculation of Diluted Income (Loss) Per Share (Details) - shares shares in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Options | Continuing Operations
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from continuing operations of diluted income (loss) per share	490	274
Restricted Stock Units (RSUs) | Continuing Operations
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from continuing operations of diluted income (loss) per share	79
Class P Unit Options | Discontinued Operations
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from continuing operations of diluted income (loss) per share		1,810

Retirement Plans - Additional I

Retirement Plans - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Defined Benefit Plan Disclosure [Line Items]
Company matching contributions to the 401(k) plan	$ 86,000	$ 37,000	$ 21,000
Maximum
Defined Benefit Plan Disclosure [Line Items]
Employer matching contribution, percent of match	3.00%

Related Party - Additional Info

Related Party - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
ANP Technologies, Inc
Related Party Transaction [Line Items]
Expenses from transactions with related party	$ 0	$ 800,000	$ 1,000,000
Research Testing Services
Related Party Transaction [Line Items]
Revenue from related parties	150,000
Foundation
Related Party Transaction [Line Items]
Revenue from related parties	28,000	11,500
Services rendered to related parties		0	$ 0
Due from related parties	0	0
University
Related Party Transaction [Line Items]
Revenue from related parties	353,000	13,000
Due from related parties	$ 29,550	$ 0

Selected Quarterly Financial 76

Selected Quarterly Financial Data (Unaudited) - Unaudited Quarterly Data (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended									12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Statement of Operations Data:
Revenue	$ 5,854	$ 5,011	$ 3,971	$ 3,440	$ 2,901		$ 2,905	$ 2,182	$ 1,588	$ 18,276	$ 9,576	$ 1,278
Cost of revenue	1,863	2,143	1,411	1,304	2,726		918	772	653	6,722	5,069	936
Gross profit	3,991	2,868	2,560	2,136	175		1,987	1,410	935	11,554	4,507	342
Operating expenses:
Research and development	818	1,523	656	561	3,650		312	252	217	3,558	4,431	521
Selling and marketing	798	893	477	301	1,913		280	243	234	2,469	2,670	581
General and administrative	1,116	1,147	457	1,889	1,956		215	168	79	4,609	2,418	230
Total operating expenses	2,732	3,563	1,590	2,751	7,519		807	663	530	10,636	9,519	1,332
Operating income (loss)	1,259	(695)	970	(615)	(7,344)		1,180	747	405	918	(5,012)	(990)
Interest and other income (expense)	57	5	(5,462)	13	7				20	(5,386)	27	0
Income (loss) before income taxes	1,316	(690)	(4,492)	(602)	(7,337)		1,180	747	425	(4,468)	(4,985)	(990)
Provision for income taxes	503	417								920	0	0
Net income (loss)	$ 813	$ (1,107)	$ (4,492)	$ (602)	$ (7,337)	$ (8,135)	$ 1,180	$ 747	$ 425	$ (5,347)	$ (8,314)	$ (4,283)
Basic and diluted income (loss) per common share:
Basic	$ 0.05	$ (0.44)	$ (5.49)	$ (0.02)	$ (0.61)
Diluted	$ 0.05	$ (0.44)	$ (5.49)	$ (0.02)	$ (0.61)