FAIR VALUE OF FINANCIAL INSTRUMENTS (Assets and Liabiliites Measured on a Nonrecurring Basis) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Liabilities:
Allowance, notes receivable	$ 100	$ 200
Recurring
Assets:
Cash	18	18
Recurring \| Level 1
Assets:
Cash	18	18
Recurring \| Level 1 \| Reported Value Measurement
Assets:
Cash	665,492	445,283
Recurring \| Level 1 \| Estimate of Fair Value Measurement
Assets:
Cash	665,492	445,283
Recurring \| Level 3 \| Reported Value Measurement
Assets:
Notes receivable, net	155	1,664
Recurring \| Level 3 \| Estimate of Fair Value Measurement
Assets:
Notes receivable, net	155	1,664
Recurring \| Level 2 \| Reported Value Measurement
Liabilities:
Fixed-rate debt	1,178,362	1,141,381
Variable-rate debt	1,524,319	1,314,973
Recurring \| Level 2 \| Estimate of Fair Value Measurement
Liabilities:
Fixed-rate debt	1,224,573	1,137,166
Variable-rate debt	$ 1,524,319	$ 1,314,973

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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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- Definition

A valuation allowance for financing receivables that are expected to be uncollectible.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953423-111524

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- References

No definition available.

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- Definition

The portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a set, unchanging rate.

+ References

No definition available.

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The portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a rate subject to change from time to time.

+ References

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- Definition

Fair value portion of an agreement for an unconditional promise by the maker to pay the holder a definite sum of money at a future date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.3(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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