Notes Receivable and Allowance for Credit Losses - Schedule Of Notes Receivable (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Notes Receivable and Allowance for Losses [Line Items]
Notes receivable	$ 140,555	$ 139,317
Total allowance for notes receivable credit losses	19,618	19,484	$ 4,556
Total notes receivable, net of allowance	120,937	119,833
Current portion, net of allowance	38,286	24,048
Long-term portion, net of allowance	82,651	95,785
Senior
Notes Receivable and Allowance for Losses [Line Items]
Notes receivable	105,333	104,716
Subordinated
Notes Receivable and Allowance for Losses [Line Items]
Notes receivable	33,672	33,234
Unsecured
Notes Receivable and Allowance for Losses [Line Items]
Notes receivable	$ 1,550	$ 1,367