Bank Loans - Schedule of Aggregate Maturities of Loans (Details) $ in Thousands	Dec. 31, 2018 USD ($)
Aggregate annual principal payments of loans payable
Within 1 year	$ 3,321
In 2020	3,890
In 2021	0
In 2022	0
In 2023	0
Total	$ 7,211

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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