Fair Value Measurements - Schedule of Assets and Liabilities Measured at Fair Value on a Recurring Basis (Parenthetical) (Details) - shares	Sep. 30, 2021	Jul. 31, 2021	Dec. 31, 2020
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Common stock, shares outstanding (in shares)	49,747,809		48,983,735
Sharecare
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Common stock, shares outstanding (in shares)		11,079,331
Other Income | Sharecare
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Common stock, shares outstanding (in shares)	11,079,331