VALUATION AND QUALIFYING ACCOUNTS (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Allowance for Doubtful Accounts, Service Credits and Other [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of the Period	$ 2,221	$ 2,052	$ 2,270
Charged to Operations/Additions	1,128	1,955	1,962
Write-offs/Deductions	(2,049)	(1,786)	(2,180)
Balance at End of the Period	1,300	2,221	2,052
Inventory Valuation Reserve [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of the Period	75	49	75
Charged to Operations/Additions	100	180	160
Write-offs/Deductions	0	(154)	(186)
Balance at End of the Period	175	75	49
Valuation Allowance of Deferred Tax Assets [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of the Period	119,277	118,723	115,746
Charged to Operations/Additions	0	554	2,977
Write-offs/Deductions	(5,087)	0	0
Balance at End of the Period	$ 114,190	$ 119,277	$ 118,723

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Total of allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 09

-Article 12

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- Definition

+ References

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- Definition

Total of the deductions in a given period to allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs, representing receivables written off as uncollectible and portions of the reserves utilized, respectively.

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