Investment Securities - Maturity (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Amortized Cost
Within one year	$ 63,347
After one year but within five years	159,011
Amortized Cost	222,358	$ 252,958
Fair value
Within one year	63,292
After one year but within five years	159,186
Total fair value	222,478	$ 256,268
Fair value
Within one year	35,102
After one year but within five years	70,350
After five years but within 10 years	24,691
Total fair value	$ 130,143

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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