Investments (Details 4) $ in Thousands	Sep. 30, 2018 USD ($)
Amortized Cost
Within 1 year	$ 39,640
After 1 year through 5 years	0
After 5 years through 10 years	0
After 10 years	6,036
Total	45,676
Fair Value
Within 1 year	39,640
After 1 year through 5 years	0
After 5 years through 10 years	0
After 10 years	5,996
Total	$ 45,636

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