Related Party Transactions - Balances of Transactions (Detail) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Related Party Transactions [Abstract]
Cash and restricted cash deposits in affiliated bank	$ 113,023	$ 126,189
Other due to/from affiliate
Accounts receivable	28,518	28,419
Prepaid expenses and other assets	4,197	4,678
Operating lease right-of-use assets	15,282	17,099
Accounts payable	3,063	4,607
Contract liabilities	35,654	35,807
Operating lease liabilities	$ 15,750	$ 17,781

Amount for accounts payable to related parties. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant