FINANCIAL INSTRUMENTS AND FAIR VALUE MEASUREMENTS (Details 3) (Recurring basis, Level 1, USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Financial Assets Measured at Fair Value
Financial Assets at Fair Value	$ 25,403	$ 15,637
Money market funds
Financial Assets Measured at Fair Value
Financial Assets at Fair Value	22,801	12,602
Voluntary Savings Plan - mutual funds held in trust
Financial Assets Measured at Fair Value
Financial Assets at Fair Value	$ 2,602	$ 3,035

This element represents the aggregate of the assets reported on the balance sheet at period end measured at fair value by the entity. This element is intended to be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258

Name:	us-gaap_AssetsFairValueDisclosure
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant