Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Available for sale, amortized cost	$ 1,203,984	$ 1,257,830
Ordinary shares, par value	$ 0.0001	$ 0.0001
Ordinary shares, shares authorized	900,000,000	900,000,000
Ordinary Shares A
Ordinary shares, shares issued	10,258,795	10,171,954
Ordinary shares, shares outstanding	10,148,346	10,095,312
Treasury shares, shares	110,449	76,642
Ordinary Shares B
Ordinary shares, shares issued	4,133,366	4,133,366
Ordinary shares, shares outstanding	4,133,366	4,133,366

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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