Notes Receivable - Summary of Company Allowance For Credit Loss (Detail) $ in Thousands	3 Months Ended
	Mar. 31, 2020 USD ($)
Unsecured Convertible Note [Member]
Financing Receivable, Credit Loss, Expense (Reversal)	$ (2,126)
Financing Receivable, Allowance for Credit Loss, Writeoff	2,126
Unsecured Non Convertible Note [Member]
Financing Receivable, Credit Loss, Expense (Reversal)	(17,546)
Financing Receivable, Allowance for Credit Loss, Writeoff	17,546
Note Receivable [Member] | Unsecured Convertible Note [Member]
Financing Receivable, Credit Loss, Expense (Reversal)	(2,090)
Financing Receivable, Allowance for Credit Loss, Writeoff	2,090
Note Receivable [Member] | Unsecured Non Convertible Note [Member]
Financing Receivable, Credit Loss, Expense (Reversal)	(14,618)
Financing Receivable, Allowance for Credit Loss, Writeoff	14,618
Accrued Interest [Member] | Unsecured Convertible Note [Member]
Financing Receivable, Credit Loss, Expense (Reversal)	(36)
Financing Receivable, Allowance for Credit Loss, Writeoff	36
Accrued Interest [Member] | Unsecured Non Convertible Note [Member]
Financing Receivable, Credit Loss, Expense (Reversal)	(2,928)
Financing Receivable, Allowance for Credit Loss, Writeoff	$ 2,928