Notes Receivable - Summary of Notes Receivable (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Accounts Notes And Loans Receivable [Line Items]
Debt instruments held	$ 355	$ 2,920
Less: notes receivable, current	(264)	(1,871)
Notes receivable, long term	91	1,049
Accucanna Note
Accounts Notes And Loans Receivable [Line Items]
Debt instruments held		1,597
NWCS and Seven Point Notes
Accounts Notes And Loans Receivable [Line Items]
Debt instruments held	$ 355	586
Related Party Notes
Accounts Notes And Loans Receivable [Line Items]
Debt instruments held		696
Other Notes
Accounts Notes And Loans Receivable [Line Items]
Debt instruments held		$ 41

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Amount, after allowance for credit loss, of financing receivable, classified as current. Includes, but is not limited to, notes and loan receivable.

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Amount, after allowance for credit loss, of financing receivable, classified as noncurrent.

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Amount, after allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement.

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