FAIR VALUE MEASUREMENTS (Financial Assets and Liabilities Not Measured on Recurring Basis) (Details) - Nonrecurring - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Balance
Assets, Fair Value Disclosure [Abstract]
Cash and Cash Equivalents, Fair Value Disclosure	$ 362,025	$ 199,449
Time Deposits and Restricted Cash and Cash Equivalents, Fair Value Disclosure	3,042	30,419
Loans Receivable, Fair Value Disclosure	5,978	6,338
Balance \| Revolving Credit Facility
Liabilities, Fair Value Disclosure [Abstract]
Borrowing under 2014 Credit Facility	25,019	35,000
Estimated Fair Value
Assets, Fair Value Disclosure [Abstract]
Cash and Cash Equivalents, Fair Value Disclosure	362,025	199,449
Time Deposits and Restricted Cash and Cash Equivalents, Fair Value Disclosure	3,042	30,419
Loans Receivable, Fair Value Disclosure	5,978	6,338
Estimated Fair Value \| Revolving Credit Facility
Liabilities, Fair Value Disclosure [Abstract]
Borrowing under 2014 Credit Facility	25,019	35,000
Estimated Fair Value \| Level 1
Assets, Fair Value Disclosure [Abstract]
Cash and Cash Equivalents, Fair Value Disclosure	362,025	199,449
Time Deposits and Restricted Cash and Cash Equivalents, Fair Value Disclosure	0	0
Loans Receivable, Fair Value Disclosure	0	0
Estimated Fair Value \| Level 1 \| Revolving Credit Facility
Liabilities, Fair Value Disclosure [Abstract]
Borrowing under 2014 Credit Facility	0	0
Estimated Fair Value \| Level 2
Assets, Fair Value Disclosure [Abstract]
Cash and Cash Equivalents, Fair Value Disclosure	0	0
Time Deposits and Restricted Cash and Cash Equivalents, Fair Value Disclosure	3,042	30,419
Loans Receivable, Fair Value Disclosure	0	0
Liabilities, Fair Value Disclosure [Abstract]
Borrowing under 2014 Credit Facility	25,019	35,000
Estimated Fair Value \| Level 3
Assets, Fair Value Disclosure [Abstract]
Cash and Cash Equivalents, Fair Value Disclosure	0	0
Time Deposits and Restricted Cash and Cash Equivalents, Fair Value Disclosure	0	0
Loans Receivable, Fair Value Disclosure	5,978	6,338
Estimated Fair Value \| Level 3 \| Revolving Credit Facility
Liabilities, Fair Value Disclosure [Abstract]
Borrowing under 2014 Credit Facility	$ 0	$ 0

Fair value portion of cash and cash equivalent items which are restricted as to withdrawal or usage and time deposits

No definition available.

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- References

No definition available.

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- Definition

Fair value portion 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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Cash
-URI http://asc.fasb.org/extlink&oid=6506951

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Cash Equivalents
-URI http://asc.fasb.org/extlink&oid=6507016

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- References

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- Definition

Fair value portion of contractual arrangement with a lender under which borrowings can be made up to a specific amount at any point in time.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Line-of-Credit Arrangement
-URI http://asc.fasb.org/extlink&oid=6517033

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- Definition

Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Glossary Loan
-URI http://asc.fasb.org/extlink&oid=6517073

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