LONG-TERM DEBT AND FINANCING ARRANGEMENTS (Details 3) (USD $)								0 Months Ended
	Mar. 31, 2014	Dec. 31, 2013	Mar. 31, 2014 Letter of Credit Agreements	Dec. 31, 2013 Letter of Credit Agreements	Mar. 31, 2014 Surety bonds	Dec. 31, 2013 Surety bonds	Mar. 31, 2014 Credit Agreement Revolving commitments	Jun. 15, 2012 Credit Agreement Term Loan	Mar. 31, 2014 Accounts receivable securitization program	Mar. 31, 2014 Accounts receivable securitization program Letter of Credit Agreements
Financing Arrangements
Debt instrument, term								5 years
Face amount of term loan								$ 100,000,000
Maximum borrowing capacity							75,000,000		75,000,000
Amount outstanding							0		0
Outstanding letters of credit			22,800,000	22,800,000						20,300,000
Remaining borrowing capacity			58,100,000						54,700,000
Amounts collateralized by restricted funds	1,903,000	1,902,000	1,900,000	1,900,000
Outstanding surety bonds under collateralized bond program					12,500,000	12,700,000
Letters of credit, outstanding amount used as collateral					3,800,000	3,800,000
Outstanding surety bonds under uncollateralized bond programs					$ 44,100,000	$ 43,800,000