Amount of cash outflow to reacquire equity classified as other.

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Number of new stock issued during the period.

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Carrying amount, attributable to parent, of an entity's issued and outstanding stock which is not included within permanent equity. 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. Includes stock with a put option held by an ESOP and stock redeemable by a holder only in the event of a change in control of the issuer.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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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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The maximum number of securities classified as temporary equity that are permitted to be issued by an entity's charter and bylaws. 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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The number of securities classified as temporary equity that have been sold (or granted) to the entity's shareholders. Securities issued include securities outstanding and securities held in treasury. 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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The number of securities classified as temporary equity that have been issued and are held by the entity's shareholders. Securities outstanding equals securities issued minus securities held in treasury. 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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Redeemable Convertible Preferred Stock - Schedule of Redeemable Preferred Shares (Details) - USD ($) $ in Thousands	Jul. 22, 2021	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Temporary Equity [Line Items]
Redeemable convertible preferred stock, authorized (in shares)						186,554,160
Redeemable convertible preferred stock, issued (in shares)						171,535,213
Redeemable convertible preferred stock, outstanding (in shares)		0				171,535,213	147,038,267	102,039,134
Redeemable convertible preferred stock		$ 0	$ 0	$ 334,439	$ 334,439	$ 334,439	$ 217,115	$ 64,355
Aggregate liquidation preference						$ 430,041
Legacy Sema4 Shareholder payout	$ 230,000
Common Stock
Temporary Equity [Line Items]
Issuance of Class B common stock to Sponsor (in Shares)	148,543,062
Series A-1 redeemable convertible preferred stock
Temporary Equity [Line Items]
Redeemable convertible preferred stock, authorized (in shares)		0				55,399,943
Redeemable convertible preferred stock, issued (in shares)		0				55,399,943
Redeemable convertible preferred stock, outstanding (in shares)		0				55,399,943
Redeemable convertible preferred stock		$ 0	0	51,811	51,811	$ 51,811
Aggregate liquidation preference		$ 0				$ 55,000
Series A-2 redeemable convertible preferred stock
Temporary Equity [Line Items]
Redeemable convertible preferred stock, authorized (in shares)		0				64,718,940
Redeemable convertible preferred stock, issued (in shares)		0				49,700,364
Redeemable convertible preferred stock, outstanding (in shares)		0				49,700,364
Redeemable convertible preferred stock		$ 0	0	46,480	46,480	$ 46,480
Aggregate liquidation preference		$ 0				$ 49,342
Series B redeemable convertible preferred stock
Temporary Equity [Line Items]
Redeemable convertible preferred stock, authorized (in shares)		0				41,937,960
Redeemable convertible preferred stock, issued (in shares)		0				41,937,960
Redeemable convertible preferred stock, outstanding (in shares)		0				41,937,960
Redeemable convertible preferred stock		$ 0	0	118,824	118,824	$ 118,824
Aggregate liquidation preference		$ 0				$ 204,302
Series C redeemable convertible preferred stock
Temporary Equity [Line Items]
Redeemable convertible preferred stock, authorized (in shares)		0				24,497,317
Redeemable convertible preferred stock, issued (in shares)		0				24,496,946
Redeemable convertible preferred stock, outstanding (in shares)		0				24,496,946
Redeemable convertible preferred stock		$ 0	$ 0	$ 117,324	$ 117,324	$ 117,324
Aggregate liquidation preference		$ 0				$ 121,397