DEBT (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2012 item	Oct. 31, 2012
Revolving Credit Agreement
Short-term debt
Line of credit maximum borrowing capacity	$ 175.0	$ 175.0
Number of anniversaries for optional annual extensions of the credit agreement	3
Period of extension	1 year
Number of options available for calculating variable interest rate	2
Letter of credit subfacility
Short-term debt
Line of credit maximum borrowing capacity	75.0	75.0
Letter of credit amount maintained	33.2
Swingline subfacility
Short-term debt
Line of credit maximum borrowing capacity	$ 25.0	$ 25.0

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 129

-Paragraph 2, 4

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19(b),22(b))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

Name:	us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant