Balance Sheets (Parentheticals) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Redeemable convertible preferred stock, authorized (in shares)	1,506,487	1,506,487
Redeemable convertible preferred stock, issued (in shares)	1,385,204	1,385,204
Redeemable convertible preferred stock, outstanding (in shares)	1,385,204	1,385,204
Redeemable convertible preferred stock, liquidation preference	$ 430,041	$ 430,041
Common stock, par value (in dollars per share)		$ 0.00001
Common stock, authorized (in shares)		15,000,000
Common stock, issued (in shares)		105,429
Common stock, outstanding (in shares)		105,429
Series A-1 redeemable convertible preferred stock
Redeemable convertible preferred stock, par value (in dollars per share)	$ 0.00001	$ 0.00001
Redeemable convertible preferred stock, authorized (in shares)	447,373	447,373
Redeemable convertible preferred stock, issued (in shares)	447,373	447,373
Redeemable convertible preferred stock, outstanding (in shares)	447,373	447,373
Redeemable convertible preferred stock, liquidation preference	$ 55,000	$ 55,000
Series A-2 redeemable convertible preferred stock
Redeemable convertible preferred stock, par value (in dollars per share)	$ 0.00001	$ 0.00001
Redeemable convertible preferred stock, authorized (in shares)	522,627	522,627
Redeemable convertible preferred stock, issued (in shares)	401,347	401,347
Redeemable convertible preferred stock, outstanding (in shares)	401,347	401,347
Redeemable convertible preferred stock, liquidation preference	$ 49,342	$ 49,342
Series B redeemable convertible preferred stock
Redeemable convertible preferred stock, par value (in dollars per share)	$ 0.00001	$ 0.00001
Redeemable convertible preferred stock, authorized (in shares)	338,663	338,663
Redeemable convertible preferred stock, issued (in shares)	338,663	338,663
Redeemable convertible preferred stock, outstanding (in shares)	338,663	338,663
Redeemable convertible preferred stock, liquidation preference	$ 204,302	$ 204,302
Series C redeemable convertible preferred stock
Redeemable convertible preferred stock, par value (in dollars per share)	$ 0.00001	$ 0.00001
Redeemable convertible preferred stock, authorized (in shares)	197,824	197,824
Redeemable convertible preferred stock, issued (in shares)	197,821	197,821
Redeemable convertible preferred stock, outstanding (in shares)	197,821	197,821
Redeemable convertible preferred stock, liquidation preference	$ 121,397	$ 121,397
Class A common stock
Common stock, par value (in dollars per share)	$ 0.00001	$ 0.00001
Common stock, authorized (in shares)	2,500,000	2,500,000
Common stock, issued (in shares)	1	1
Common stock, outstanding (in shares)	1	1
Class B common stock
Common stock, par value (in dollars per share)	$ 0.00001	$ 0.00001
Common stock, authorized (in shares)	15,000,000	15,000,000
Common stock, issued (in shares)	604,649	105,429
Common stock, outstanding (in shares)	604,649	105,429
CM Life Sciences, Inc.
Preferred stock par value (in Dollars per share)	$ 0.0001	$ 0.0001
Preferred stock, shares authorized	1,000,000	1,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
CM Life Sciences, Inc. \| Class A common stock
Redeemable convertible preferred stock, par value (in dollars per share)		$ 10.00
Common stock subject to possible redemption	29,474,795	35,321,987
Common stock subject to possible redemption (in dollars per share)	$ 10.00	$ 10.00
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common stock, authorized (in shares)	380,000,000	380,000,000
Common stock, issued (in shares)	14,800,205	8,953,013
Common stock, outstanding (in shares)	14,800,205	8,953,013
CM Life Sciences, Inc. \| Class B common stock
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common stock, authorized (in shares)	20,000,000	20,000,000
Common stock, issued (in shares)	11,068,750	11,068,750
Common stock, outstanding (in shares)	11,068,750	11,068,750

Common stock subject to possible redemption per share.

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Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.

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The aggregate liquidation preference (or restrictions) of stock classified as temporary equity that has a preference in involuntary liquidation considerably in excess of the par or stated value of the shares. The liquidation preference is the difference between the preference in liquidation and the par or stated values of the share. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. If convertible, the issuer does not control the actions or events necessary to issue the maximum number of shares that could be required to be delivered under the conversion option if the holder exercises the option to convert the stock to another class of equity. If the security is a warrant or a rights issue, the warrant or rights issue is considered to be temporary equity if the issuer cannot demonstrate that it would be able to deliver upon the exercise of the option by the holder in all cases. Includes stock with put option held by ESOP and stock redeemable by holder only in the event of a change in control of the issuer.

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