UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF REDEEMABLE CONVERTIBLE PREFERRED STOCK AND STOCKHOLDERS' EQUITY (DEFICIT) - USD ($) $ in Thousands	Total	Redeemable Convertible Preferred Stock [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Deficit [Member]	Total Histogen, Inc. Stockholders' Equity (Deficit) [Member]	Noncontrolling Interest [Member]
Beginning balance at Dec. 31, 2021	$ 20,186		$ 5	$ 98,839	$ (77,652)	$ 21,192	$ (1,006)
Beginning balance, shares at Dec. 31, 2021			2,497,450
Issuance of common stock, net of issuance costs	(9)			(9)		(9)
Issuance of redeemable convertible preferred stock, net of issuance costs		$ 4,296
Issuance of redeemable convertible preferred stock, net of issuance costs, shares		5,000
Stock-based compensation expense	165			165		165
Net (loss) gain	(684)				(673)	(673)	(11)
Ending balance at Mar. 31, 2022	19,658		$ 5	98,995	(78,325)	20,675	(1,017)
Ending balance, shares at Mar. 31, 2022			2,497,450
Ending balance at Mar. 31, 2022		$ 4,296
Ending balance, shares at Mar. 31, 2022		5,000
Beginning balance at Dec. 31, 2021	20,186		$ 5	98,839	(77,652)	21,192	(1,006)
Beginning balance, shares at Dec. 31, 2021			2,497,450
Net (loss) gain	(4,078)
Ending balance at Jun. 30, 2022	15,306		$ 5	98,037	(81,713)	16,329	(1,023)
Ending balance, shares at Jun. 30, 2022			2,497,450
Beginning balance at Mar. 31, 2022	19,658		$ 5	98,995	(78,325)	20,675	(1,017)
Beginning balance, shares at Mar. 31, 2022			2,497,450
Issuance of redeemable convertible preferred stock, net ofissuance costs	(119)			(119)		(119)
Accretion of issuance costs, discount and redemption feature of redeemable convertible preferred stock	(954)	$ 954		(954)		(954)
Redemption of redeemable convertible preferred stock, shares		(5,000)
Redemption of redeemable convertible preferred stock		$ (5,250)
Stock-based compensation expense	115			115		115
Net (loss) gain	(3,394)				(3,388)	(3,388)	(6)
Ending balance at Jun. 30, 2022	15,306		$ 5	98,037	(81,713)	16,329	(1,023)
Ending balance, shares at Jun. 30, 2022			2,497,450
Beginning balance at Dec. 31, 2022	13,376		$ 5	102,673	(88,273)	14,405	(1,029)
Beginning balance, shares at Dec. 31, 2022			4,271,759
Stock-based compensation expense	419			419		419
Net (loss) gain	(3,473)				(3,470)	(3,470)	(3)
Ending balance at Mar. 31, 2023	10,322		$ 5	103,092	(91,743)	11,354	(1,032)
Ending balance, shares at Mar. 31, 2023			4,271,759
Beginning balance at Dec. 31, 2022	13,376		$ 5	102,673	(88,273)	14,405	(1,029)
Beginning balance, shares at Dec. 31, 2022			4,271,759
Net (loss) gain	(5,562)
Ending balance at Jun. 30, 2023	8,265		$ 5	103,124	(93,835)	9,294	(1,029)
Ending balance, shares at Jun. 30, 2023			4,271,759
Beginning balance at Mar. 31, 2023	10,322		$ 5	103,092	(91,743)	11,354	(1,032)
Beginning balance, shares at Mar. 31, 2023			4,271,759
Stock-based compensation expense	32			32		32
Net (loss) gain	(2,089)				(2,092)	(2,092)	3
Ending balance at Jun. 30, 2023	$ 8,265		$ 5	$ 103,124	$ (93,835)	$ 9,294	$ (1,029)
Ending balance, shares at Jun. 30, 2023			4,271,759