Fair Value of Financial Instruments (Table) (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017	Jun. 30, 2017
FAIR VALUE OF FINANCIAL INSTRUMENTS [ABSTRACT]
Cash and cash equivalents - Book Value	$ 40,577	$ 24,047	$ 79,749
Cash and cash equivalents - Fair Value	40,577	24,047
Restricted cash - Book Value	402	5,886
Restricted cash - Fair Value	402	5,886
Loans receivable from affiliates - Book Value	11,861	11,706
Loans receivable from affiliates - Fair Value	11,861	11,706
Amounts due from related parties, long-term - Book Value	44,009	34,891
Amounts due from related parties, long-term - Fair Value	44,009	34,891
Amounts due from related parties, short-term - Book Value	11,735	10,545
Amounts due from related parties, short-term - Fair Value	11,735	10,545
Term Loan B facility, net - Book Value	(416,920)	(425,144)
Term Loan B facility, net - Fair Value	(430,542)	(441,471)
Other long-term debt, net - Book Value	(77,542)	(68,319)
Other long-term debt, net - Fair Value	(78,205)	(69,161)
Notes receivable, net of current portion - Book Value	13,760	15,897
Notes receivable, net of current portion - Fair Value	13,760	15,897
Receivable from affiliates - Book Value	4,386	4,253
Receivable from affiliates - Fair Value	$ 4,386	$ 4,253

Fair value as of the balance sheet date of receivables due from all related parties.

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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