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Amount of investment in debt and equity securities categorized neither as trading securities nor held-to-maturity securities and intended be sold or mature one year or operating cycle, if longer.

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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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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

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Amount of cash and cash equivalents restricted as to withdrawal or usage, classified as noncurrent. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, 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.

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FAIR VALUE MEASUREMENTS AND FINANCIAL INSTRUMENTS (Details 2) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017	Jun. 30, 2017	Dec. 31, 2016
Assets, Fair Value Disclosure
Cash and cash equivalents	$ 84,569	$ 105,006
Restricted cash	5,783	3,837	$ 4,398	$ 4,100
Investment in equity securities	43,185	49,153
Liabilities, Fair Value Disclosure
Long-term debt, carrying amount	403,760	413,581
Level 1 \| Fair Value, Measurements, Recurring
Assets, Fair Value Disclosure
Cash and cash equivalents	84,569	105,006
Restricted cash	5,783	3,837
Investment in equity securities	43,185	49,153
Liabilities, Fair Value Disclosure
Long-term debt, fair value	0	0
Level 2 \| Fair Value, Measurements, Recurring
Assets, Fair Value Disclosure
Cash and cash equivalents	0	0
Restricted cash	0	0
Investment in equity securities	0	0
Liabilities, Fair Value Disclosure
Long-term debt, fair value	401,067	407,377
Level 3 \| Fair Value, Measurements, Recurring
Assets, Fair Value Disclosure
Cash and cash equivalents	0	0
Restricted cash	0	0
Investment in equity securities	0	0
Liabilities, Fair Value Disclosure
Long-term debt, fair value	$ 0	$ 0