| Document and Entity Information | 12 Months Ended |
| Dec. 31, 2022 | |
| Cover [Abstract] | |
| Document Type | DEF 14A |
| Amendment Flag | false |
| Entity Registrant Name | FULGENT GENETICS, INC. |
| Entity Central Index Key | 0001674930 |
| Pay vs Performance Disclosure - USD ($) | 12 Months Ended | ||
| Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020 | |
| Pay vs Performance Disclosure [Table] | |||
| Pay vs Performance [Table Text Block] | The following table shows the relationship between executive compensation actually paid (“CAP”) to our Principal Executive Officer (“PEO”) and other named executive officers, including our Chief Financial Officer, Chief Scientific Officer and Laboratory Director, and President and Chief Operating Officer (“Non-PEO NEOs”), and certain financial performance of the Company during the last three fiscal years ended December 31, 2022, 2021 and 2020. Year Summary Compensation Table Total for PEO Compensation Actually Paid to PEO Average Summary Compensation Table Total for Non-PEO NEOs Average Compensation Actually Paid to Non-PEO NEOs Value of Initial Fixed $100 Investment Based On: Net Income Revenue Total Share-holder Return Peer Group Total Share-holder Return ($) ($) ($) ($) ($) ($) ($ Millions) ($ Millions) (a) (b) (1) (c) (2) (d) (3) (e) (4) (f) (5) (g) (6) (h) (7) (i) (8) 2022 5,233,873 3,448,273 3,829,640 ( 2,733,189 ) 231 111 143.4 619.0 2021 5,664,303 5,664,303 758,236 6,545,715 780 125 507.4 992.6 2020 248,000 248,000 2,507,503 6,407,036 404 126 214.3 421.7 Footnotes: (1) The dollar amounts reported in column (b) are the amounts of total compensation reported for Ming Hsieh , Chief Executive Officer (our Principal Executive Officer, or PEO), for each corresponding year in the “Total” column of the Summary Compensation Table. (2) The dollar amounts reported in column (c) represent the amount of CAP to Ming Hsieh, as computed in accordance with SEC rules. The dollar amounts do not reflect the actual amount of compensation earned by or paid to Ming Hsieh during the applicable year. In accordance with SEC rules, the following adjustments were made to Ming Hsieh’s total compensation for each year to determine CAP: Footnote (2) - Table 1 Year Reported Summary Compensation Table Total for PEO Reported Value of Equity Awards Equity Award Adjustments Compensation Actually Paid to PEO ($) ($) ($) ($) (a) (b) (c) (i) (d) (ii) (e) 2022 5,233,873 3,572,400 1,786,800 3,448,273 2021 5,664,303 — — 5,664,303 2020 248,000 — — 248,000 i. The grant date fair value of equity awards in column (c) of Footnote (2) - Table 1 represents the total of the amounts reported in the “Stock Awards” column in the Summary Compensation Table for the applicable year. ii. The equity award adjustments in column (d) of Footnote (2) - Table 1 include the addition (or subtraction, as applicable) of the following: (1) the year-end fair value of any equity awards granted in the applicable year that are outstanding and unvested as of the end of the year; (2) the amount of change as of the end of the applicable year (from the end of the prior fiscal year) in fair value of any awards granted in prior years that are outstanding and unvested as of the end of the applicable year; (3) for awards granted in prior years that vest in the applicable year, the amount equal to the change as of the vesting date (from the end of the prior fiscal year) in fair value. The valuation assumptions used to calculate fair values did not materially differ from those disclosed at the time of grant. The amounts deducted or added in calculating the equity award adjustments are as follows: Footnote (2) - Table 2 Year Year End Fair Value of Equity Awards Year over Year Change in Fair Value of Outstanding and Unvested Equity Awards Fair Value as of Vesting Date of Equity Awards Granted and Vested in the Year Year over Year Change in Fair Value of Equity Awards Granted in Prior Years that Vested in the Year Fair Value at the End of the Prior Year of Equity Awards that Failed to Meet Vesting Conditions in the Year Value of Dividends or other Earnings Paid on Stock or Option Awards not Otherwise Reflected in Fair Value or Total Compensation Total Equity Award Adjustments ($) ($) ($) ($) ($) ($) ($) (a) (b) (c) (d) (e) (f) (g) (h) 2022 1,786,800 — — — — — 1,786,800 2021 — — — — — — — 2020 — — — — — — — (3) The dollar amounts reported in column (d) represent the average of the amounts reported for the Company’s NEOs as a group (excluding the Company’s PEO) in the “Total” column of the Summary Compensation Table in each applicable year. The names of each of the NEOs (excluding the Company’s PEO) included for purposes of calculating the average amounts in each applicable year are as follows: Paul Kim, Chief Financial Officer, Hanlin Gao, Chief Scientific Officer and Laboratory Director, and Jian Xie, President and Chief Operating Officer, for 2020, 2021, and 2022, . (4) The dollar amounts reported in column (e) represent the average amount of CAP to the NEOs as a group (excluding the Company’s PEO), as computed in accordance with SEC rules. The dollar amounts do not reflect the actual average amount of compensation earned by or paid to the NEOs as a group (excluding the Company’s PEO) during the applicable year. In accordance with the SEC rules, the following adjustments were made to average total compensation for the NEOs as a group (excluding the Company’s PEO) for each year to determine the CAP, using the same methodology described above in Footnote 2: Footnote (4) - Table 1 Year Average Reported Summary Compensation Table Total for Non-PEO NEOs Average Reported Value of Equity Awards Average Equity Award Adjustments Average Compensation Actually Paid to Non-PEO NEOs ($) ($) ($) ($) (a) (b) (c) (d) (i) (e) 2022 3,829,640 3,115,000 ( 3,447,829 ) ( 2,733,189 ) 2021 758,236 89,857 5,877,336 6,545,715 2020 2,507,503 2,273,600 6,173,133 6,407,036 i. The amounts deducted or added in calculating the total average equity award adjustments are as follows: Footnote (4) - Table 2 Year Average Year End Fair Value of Equity Awards Year over Year Average Change in Fair Value of Outstanding and Unvested Equity Awards Average Fair Value as of Vesting Date of Equity Awards Granted and Vested in the Year Year over Year Average Change in Fair Value of Equity Awards Granted in Prior Years that Vested in the Year Average Fair Value at the End of the Prior Year of Equity Awards that Failed to Meet Vesting Conditions in the Year Average Value of Dividends or other Earnings Paid on Stock or Option Awards not Otherwise Reflected in Fair Value or Total Compensation Total Average Equity Award Adjustments ($) ($) ($) ($) ($) ($) ($) (a) (b) (c) (d) (e) (f) (g) (h) 2022 1,489,000 ( 3,304,514 ) — ( 1,632,315 ) — — ( 3,447,829 ) 2021 117,355 3,904,479 — 1,855,502 — — 5,877,336 2020 4,168,000 1,572,103 — 433,030 — — 6,173,133 (5) The cumulative total shareholder return (“TSR”) amounts reported in column (f) are calculated in the same manner as required under Item 201(e) of Regulation S-K, measuring the total shareholder return from the market close on the last trading day before the earliest fiscal year in the table, or December 31, 2019, through to and including the end of the fiscal year for which total shareholder return is calculated, or December 31, 2022. (6) The weighted peer group TSR amounts reported in column (g) reflect the Company’s peer group (NASDAQ Biotechnology Index) as reflected in our Annual Report on Form 10-K pursuant to Item 201(e) of Regulation S-K for the fiscal year ended December 31, 2022. Each year reflects what the cumulative value of $100 would be, including the reinvestment of dividends, if such amount were invested as of market close on December 31, 2019. (7) The dollar amounts reported in column (h) are the Company’s net income amounts reflected in the Company’s audited financial statements for the applicable year. (8) While the Company uses numerous financial and non-financial performance measures for the purpose of evaluating performance for the Company’s compensation programs, the Company has determined that revenue is the financial performance measure that, in the Company’s assessment, represents the most important performance measure (that is not otherwise required to be disclosed in the Pay Versus Performance Table) used by the company to link compensation actually paid to the Company’s NEOs, for the most recently completed fiscal year, to company performance. The dollar amounts reported in column (i) are the Company’s revenue amounts reflected in the Company’s audited financial statements for the applicable year. | ||
| Company Selected Measure Name | Revenue | ||
| Named Executive Officers, Footnote [Text Block] | (1) The dollar amounts reported in column (b) are the amounts of total compensation reported for Ming Hsieh , Chief Executive Officer (our Principal Executive Officer, or PEO), for each corresponding year in the “Total” column of the Summary Compensation Table. | ||
| Peer Group Issuers, Footnote [Text Block] | (6) The weighted peer group TSR amounts reported in column (g) reflect the Company’s peer group (NASDAQ Biotechnology Index) as reflected in our Annual Report on Form 10-K pursuant to Item 201(e) of Regulation S-K for the fiscal year ended December 31, 2022. Each year reflects what the cumulative value of $100 would be, including the reinvestment of dividends, if such amount were invested as of market close on December 31, 2019. | ||
| PEO Total Compensation Amount | $ 5,233,873 | $ 5,664,303 | $ 248,000 |
| PEO Actually Paid Compensation Amount | $ 3,448,273 | 5,664,303 | 248,000 |
| Adjustment To PEO Compensation, Footnote [Text Block] | (2) The dollar amounts reported in column (c) represent the amount of CAP to Ming Hsieh, as computed in accordance with SEC rules. The dollar amounts do not reflect the actual amount of compensation earned by or paid to Ming Hsieh during the applicable year. In accordance with SEC rules, the following adjustments were made to Ming Hsieh’s total compensation for each year to determine CAP: Footnote (2) - Table 1 Year Reported Summary Compensation Table Total for PEO Reported Value of Equity Awards Equity Award Adjustments Compensation Actually Paid to PEO ($) ($) ($) ($) (a) (b) (c) (i) (d) (ii) (e) 2022 5,233,873 3,572,400 1,786,800 3,448,273 2021 5,664,303 — — 5,664,303 2020 248,000 — — 248,000 i. The grant date fair value of equity awards in column (c) of Footnote (2) - Table 1 represents the total of the amounts reported in the “Stock Awards” column in the Summary Compensation Table for the applicable year. ii. The equity award adjustments in column (d) of Footnote (2) - Table 1 include the addition (or subtraction, as applicable) of the following: (1) the year-end fair value of any equity awards granted in the applicable year that are outstanding and unvested as of the end of the year; (2) the amount of change as of the end of the applicable year (from the end of the prior fiscal year) in fair value of any awards granted in prior years that are outstanding and unvested as of the end of the applicable year; (3) for awards granted in prior years that vest in the applicable year, the amount equal to the change as of the vesting date (from the end of the prior fiscal year) in fair value. The valuation assumptions used to calculate fair values did not materially differ from those disclosed at the time of grant. The amounts deducted or added in calculating the equity award adjustments are as follows: Footnote (2) - Table 2 Year Year End Fair Value of Equity Awards Year over Year Change in Fair Value of Outstanding and Unvested Equity Awards Fair Value as of Vesting Date of Equity Awards Granted and Vested in the Year Year over Year Change in Fair Value of Equity Awards Granted in Prior Years that Vested in the Year Fair Value at the End of the Prior Year of Equity Awards that Failed to Meet Vesting Conditions in the Year Value of Dividends or other Earnings Paid on Stock or Option Awards not Otherwise Reflected in Fair Value or Total Compensation Total Equity Award Adjustments ($) ($) ($) ($) ($) ($) ($) (a) (b) (c) (d) (e) (f) (g) (h) 2022 1,786,800 — — — — — 1,786,800 2021 — — — — — — — 2020 — — — — — — — | ||
| Non-PEO NEO Average Total Compensation Amount | $ 3,829,640 | 758,236 | 2,507,503 |
| Non-PEO NEO Average Compensation Actually Paid Amount | $ (2,733,189) | 6,545,715 | 6,407,036 |
| Adjustment to Non-PEO NEO Compensation Footnote [Text Block] | (4) The dollar amounts reported in column (e) represent the average amount of CAP to the NEOs as a group (excluding the Company’s PEO), as computed in accordance with SEC rules. The dollar amounts do not reflect the actual average amount of compensation earned by or paid to the NEOs as a group (excluding the Company’s PEO) during the applicable year. In accordance with the SEC rules, the following adjustments were made to average total compensation for the NEOs as a group (excluding the Company’s PEO) for each year to determine the CAP, using the same methodology described above in Footnote 2: Footnote (4) - Table 1 Year Average Reported Summary Compensation Table Total for Non-PEO NEOs Average Reported Value of Equity Awards Average Equity Award Adjustments Average Compensation Actually Paid to Non-PEO NEOs ($) ($) ($) ($) (a) (b) (c) (d) (i) (e) 2022 3,829,640 3,115,000 ( 3,447,829 ) ( 2,733,189 ) 2021 758,236 89,857 5,877,336 6,545,715 2020 2,507,503 2,273,600 6,173,133 6,407,036 i. The amounts deducted or added in calculating the total average equity award adjustments are as follows: Footnote (4) - Table 2 Year Average Year End Fair Value of Equity Awards Year over Year Average Change in Fair Value of Outstanding and Unvested Equity Awards Average Fair Value as of Vesting Date of Equity Awards Granted and Vested in the Year Year over Year Average Change in Fair Value of Equity Awards Granted in Prior Years that Vested in the Year Average Fair Value at the End of the Prior Year of Equity Awards that Failed to Meet Vesting Conditions in the Year Average Value of Dividends or other Earnings Paid on Stock or Option Awards not Otherwise Reflected in Fair Value or Total Compensation Total Average Equity Award Adjustments ($) ($) ($) ($) ($) ($) ($) (a) (b) (c) (d) (e) (f) (g) (h) 2022 1,489,000 ( 3,304,514 ) — ( 1,632,315 ) — — ( 3,447,829 ) 2021 117,355 3,904,479 — 1,855,502 — — 5,877,336 2020 4,168,000 1,572,103 — 433,030 — — 6,173,133 | ||
| Compensation Actually Paid vs. Total Shareholder Return [Text Block] | CAP and Total Shareholder Return | ||
| Compensation Actually Paid vs. Net Income [Text Block] | CAP and Earnings Per Share | ||
| Compensation Actually Paid vs. Company Selected Measure [Text Block] | CAP and Revenue | ||
| Tabular List [Table Text Block] | The most important financial performance measures used by the Company to link executive compensation actually paid to the Company’s NEOs, for the most recently completed fiscal year, to the Company’s performance are as follows: (1) Revenue (2) EBITDA (3) Total Shareholder Return (4) Earnings Per Share (5) Core Revenue | ||
| Total Shareholder Return Amount | $ 231 | 780 | 404 |
| Peer Group Total Shareholder Return Amount | 111 | 125 | 126 |
| Net Income (Loss) | $ 143,400,000 | $ 507,400,000 | $ 214,300,000 |
| Company Selected Measure Amount | 619,000,000 | 992,600,000 | 421,700,000 |
| PEO Name | Ming Hsieh | Ming Hsieh | Ming Hsieh |
| PEO [Member] | Reported Value of Equity Awards | |||
| Pay vs Performance Disclosure [Table] | |||
| Adjustment to Compensation Amount | $ 3,572,400 | ||
| PEO [Member] | Equity Award Adjustments | |||
| Pay vs Performance Disclosure [Table] | |||
| Adjustment to Compensation Amount | 1,786,800 | ||
| PEO [Member] | Year End Fair Value of Equity Awards | |||
| Pay vs Performance Disclosure [Table] | |||
| Adjustment to Compensation Amount | 1,786,800 | ||
| Non-PEO NEO [Member] | |||
| Pay vs Performance Disclosure [Table] | |||
| Adjustment to Compensation Amount | $ (3,447,829) | $ 5,877,336 | $ 6,173,133 |
| Non-PEO NEO [Member] | Measure [Axis]: 1 | |||
| Pay vs Performance Disclosure [Table] | |||
| Measure Name | Revenue | ||
| Non-PEO NEO [Member] | Measure [Axis]: 2 | |||
| Pay vs Performance Disclosure [Table] | |||
| Measure Name | EBITDA | ||
| Non-PEO NEO [Member] | Measure [Axis]: 3 | |||
| Pay vs Performance Disclosure [Table] | |||
| Measure Name | Total Shareholder Return | ||
| Non-PEO NEO [Member] | Measure [Axis]: 4 | |||
| Pay vs Performance Disclosure [Table] | |||
| Measure Name | Earnings Per Share | ||
| Non-PEO NEO [Member] | Measure [Axis]: 5 | |||
| Pay vs Performance Disclosure [Table] | |||
| Measure Name | Core Revenue | ||
| Non-PEO NEO [Member] | Reported Value of Equity Awards | |||
| Pay vs Performance Disclosure [Table] | |||
| Adjustment to Compensation Amount | $ 3,115,000 | 89,857 | 2,273,600 |
| Non-PEO NEO [Member] | Equity Award Adjustments | |||
| Pay vs Performance Disclosure [Table] | |||
| Adjustment to Compensation Amount | (3,447,829) | 5,877,336 | 6,173,133 |
| Non-PEO NEO [Member] | Year End Fair Value of Equity Awards | |||
| Pay vs Performance Disclosure [Table] | |||
| Adjustment to Compensation Amount | 1,489,000 | 117,355 | 4,168,000 |
| Non-PEO NEO [Member] | Year over Year Change in Fair Value of Outstanding and Unvested Equity Awards | |||
| Pay vs Performance Disclosure [Table] | |||
| Adjustment to Compensation Amount | (3,304,514) | 3,904,479 | 1,572,103 |
| Non-PEO NEO [Member] | Year over Year Change in Fair Value of Equity Awards Granted in Prior Years that Vested in the Year | |||
| Pay vs Performance Disclosure [Table] | |||
| Adjustment to Compensation Amount | $ (1,632,315) | $ 1,855,502 | $ 433,030 |
