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For banks and other depository institutions: Includes cash on hand (currency and coin), cash items in process of collection, noninterest bearing deposits due from other financial institutions (including corporate credit unions), and noninterest bearing balances with the Federal Reserve Banks, Federal Home Loan Banks and central banks.

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Cash and Cash Equivalents - Summary of Cash and Cash Equivalents (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Cash And Cash Equivalents [Line Items]
Cash at bank and in hand	$ 75,111	$ 36,778
Cash equivalents	821	26,174
Cash and cash equivalents	75,932	62,952	$ 229,660
Denominated in US$
Cash And Cash Equivalents [Line Items]
Cash and cash equivalents	62,478	58,254
Denominated in RMB
Cash And Cash Equivalents [Line Items]
Cash and cash equivalents	6,761	3,916
Denominated in Hong Kong dollar
Cash And Cash Equivalents [Line Items]
Cash and cash equivalents	5,948	20
Denominated in Australia dollar
Cash And Cash Equivalents [Line Items]
Cash and cash equivalents	$ 745	$ 762