Other Non-Current Assets - Schedule of Other Non-Current Assets (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Other Assets, Noncurrent Disclosure [Abstract]
Deposits and other	$ 919	$ 423
Due (to)/from Rhino GP	(68)	(61)
Non-current receivable	27,806	27,806
Deferred expenses	324	340
Total	$ 28,981	$ 28,508

Amount due from customers or clients, more than one year from the balance sheet date, for goods or services that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.

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Amount of deferred cost, excluding capitalized cost related to contract with customer; classified as noncurrent.

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Carrying value of amounts transferred to third parties for security purposes that are expected to be returned or applied towards payment after one year or beyond the operating cycle, if longer.

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Amount of noncurrent assets classified as other.

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Amount of receivables to be collected from related parties net of obligations owed to related parties after one year or beyond the normal operating cycle, if longer where one party can exercise control or significant influence over another party including, but not limited to, affiliates, owners or officers and their immediate families and pension trusts.

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