INCOME TAXES (Summary of Unrecognized Tax Benefits) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
INCOME TAXES
Unrecognized tax benefits related to deferred tax assets and federal tax benefit of state income tax items	$ 16,700
Decrease in provision for income taxes due to reduction of gross unrecognized tax benefits	1,400
Accrued interest and penalties	400	$ 400
Unrecognized tax benefits
Beginning balance-gross unrecognized tax benefits (UTB's)	20,137	22,694
Additions based on tax positions related to the current year			$ 48
Reductions for tax positions related to prior years			(835)
Lapse of statute of limitations	(1,409)	(2,557)	(21,901)
Ending balance-gross unrecognized tax benefits ("UTB"s)	18,728	20,137	22,694
UTB's as a credit in deferred taxes	(14,604)	(14,604)	(14,604)
Federal benefit of state taxes	(2,063)	(2,063)	(2,063)
UTB's that would impact the effective tax rate	$ 2,061	$ 3,470	$ 6,027

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of unrecognized tax benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15A
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=65882285&loc=SL6600010-109319

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Unrecognized Tax Benefit
-URI http://asc.fasb.org/extlink&oid=6527854

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Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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- Definition

Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32718-109319

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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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Represents the decrease in amount of income tax expense (benefits) due to reduction in gross unrecognized tax benefits.

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Represents the portion of unrecognized tax benefits, which is related to credit in deferred tax assets.

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Represents the portion of unrecognized tax benefits, which is related to the federal tax benefit of state income tax items.

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Represents the portion of unrecognized tax benefits, which is related to deferred tax assets and the federal tax benefit of state income tax items.

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