Commitments and Contingencies (Details)	12 Months Ended
	Dec. 31, 2012 member	Sep. 30, 2021 store	Dec. 31, 2020 claim
Commitments and Contingencies Disclosure [Abstract]
Guarantor obligations, number of leases | store		72
Sample size | member	200
Radcliffe and Flaim v. Aetna Inc., et al | Pending Litigation
Loss Contingencies [Line Items]
Number of claims | claim			2