Revenue From Contracts With Customers - Summary of Allowance for Notes Receivable (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Mar. 31, 2020	Jun. 30, 2021	Jun. 30, 2020
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning balance		$ 18
Accounting Standards Update [Extensible List]	us-gaap:AccountingStandardsUpdate201613Member	us-gaap:AccountingStandardsUpdate201912Member	us-gaap:AccountingStandardsUpdate201613Member
Provision for credit losses		$ (3)	$ 5
Ending balance		$ 15	24
Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning balance	$ 19		$ 19