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Related Parties - Additional Information (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021
ANP Technologies, Inc., \| Ming Hsieh
Related Party Transaction [Line Items]
Ownership percentage	20.00%		20.00%
AHMC Healthcare Inc. \| Genetic Sequencing Services
Related Party Transaction [Line Items]
Revenue from related parties	$ 253,000	$ 738,000	$ 1,000,000.0	$ 1,900,000
Trade accounts receivable, net from related parties	220,000		220,000		$ 556,000
Fulgent Pharma LLC
Related Party Transaction [Line Items]
Related party costs	0	0	0	0
Due to related parties	54,000		54,000		679,000,000
Fulgent Pharma LLC \| Research Development Service
Related Party Transaction [Line Items]
Expenses to transport employees and supplies	0	97,000	0	205,000
PTJ Associates Inc
Related Party Transaction [Line Items]
Expenses to transport employees and supplies	99,000	0	235,000	0
Accounts payable to related parties	67,000		67,000		$ 0
ANP Technologies Inc
Related Party Transaction [Line Items]
Due to related parties	0		0
Purchase of COVID-19 antigen rapid tests kits from related party	$ 90,000	$ 0	$ 160,000	$ 0