Notes Receivables - Summary of Company's notes receivable (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Total	$ 28,172	$ 28,722
Unsecured non-convertible note [Member]
Total	26,046	$ 28,722
Unsecured convertible note [Member]
Total	$ 2,126

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(3))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Name:	us-gaap_NotesAndLoansReceivableNetNoncurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant