INTANGIBLE ASSETS (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
Mar. 31, 2013	Dec. 31, 2012
INTANGIBLE ASSETS [Abstract]
Goodwill	$ 28,515	$ 28,515
Identifiable intangible assets [Abstract]
Gross Carrying Amount	41,826	41,797
Accumulated Amortization	23,932	22,939
Amortization of identifiable finite-lived intangible assets [Abstract]
Amortization of identifiable intangible assets	994
Finite-lived intangible assets, future amortization expense [Abstract]
Remainder of 2013	2,984
2014	4,000
2015	4,000
2016	4,000
2017	1,400
2018	600
Indefinite-lived intangible assets	0
Customer Lists [Member]
Identifiable intangible assets [Abstract]
Amortization period	10 years	10 years
Gross Carrying Amount	37,142	37,142
Accumulated Amortization	21,822	20,912
Regulatory Registration Costs [Member]
Identifiable intangible assets [Abstract]
Gross Carrying Amount	1,438	1,411
Accumulated Amortization	399	361
Regulatory Registration Costs [Member] \| Minimum [Member]
Identifiable intangible assets [Abstract]
Amortization period	5 years	5 years
Regulatory Registration Costs [Member] \| Maximum [Member]
Identifiable intangible assets [Abstract]
Amortization period	10 years	10 years
Patents & Trade Secrets [Member]
Identifiable intangible assets [Abstract]
Gross Carrying Amount	1,582	1,581
Accumulated Amortization	785	765
Patents & Trade Secrets [Member] \| Minimum [Member]
Identifiable intangible assets [Abstract]
Amortization period	15 years	15 years
Patents & Trade Secrets [Member] \| Maximum [Member]
Identifiable intangible assets [Abstract]
Amortization period	17 years	17 years
Trademarks & Trade Names [Member]
Identifiable intangible assets [Abstract]
Amortization period	17 years	17 years
Gross Carrying Amount	910	909
Accumulated Amortization	421	408
Other [Member]
Identifiable intangible assets [Abstract]
Gross Carrying Amount	754	754
Accumulated Amortization	$ 505	$ 493
Other [Member] \| Minimum [Member]
Identifiable intangible assets [Abstract]
Amortization period	5 years	5 years
Other [Member] \| Maximum [Member]
Identifiable intangible assets [Abstract]
Amortization period	10 years	10 years

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

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-Name Accounting Standards Codification

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Amount of amortization expense expected to be recognized after the fifth fiscal year following the latest fiscal year for assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

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Amount of amortization expense expected to be recognized in the remainder of the fiscal year following the latest fiscal year ended for assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount of amortization expense expected to be recognized during the fifth fiscal year following the latest fiscal year for assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount of amortization expense expected to be recognized during the third fiscal year following the latest fiscal year for assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount of amortization expense expected to be recognized during the second fiscal year following the latest fiscal year for assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Carrying amount as of the balance sheet date, which is the cumulative amount paid and (if applicable) the fair value of any noncontrolling interest in the acquiree, adjusted for any amortization recognized prior to the adoption of any changes in generally accepted accounting principles (as applicable) and for any impairment charges, in excess of the fair value of net assets acquired in one or more business combination transactions.

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Carrying amount of assets (excluding financial assets) that lack physical substance, excluding goodwill, having a projected indefinite period of benefit.

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