Commitments and Contingencies - Schedule of principal contractual commitments outstanding under our capital leases (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Commitments and Contingencies Disclosure [Abstract]
2019	$ 1,052
2020	1,052
2021	1,052
2022	909
2023	451
Thereafter	0
Total minimum lease payments	4,516
Less: Amount representing interest	(424)
Present value of capital lease obligations	4,092
Less current portion of capital lease obligations	(883)	$ (338)
Total long-term capital lease obligations	$ 3,209	$ 1,351

Amount of capital lease obligation due within one year or the normal operating cycle, if longer.

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-Name Accounting Standards Codification
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-SubTopic 10
-Section S99
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Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal, through the balance sheet date and due to be paid more than one year (or one operating cycle, if longer) after the balance sheet date.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Amount of minimum lease payments for capital leases due 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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Amount of minimum lease payments for capital leases due after 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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Amount necessary to reduce net minimum lease payments to present value for capital leases.

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Present value of minimum lease payments for capital leases net of executory costs, including amounts paid by the lessee to the lessor for insurance, maintenance and taxes.

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