LONG-TERM DEBT AND FINANCING ARRANGEMENTS (Details 3) (USD $)			6 Months Ended			6 Months Ended		0 Months Ended
	Jun. 30, 2013	Dec. 31, 2012	Jun. 30, 2013 Accounts receivable securitization program	Jun. 30, 2013 Letter of Credit Agreements	Jun. 30, 2013 Surety bonds	Jun. 30, 2013 Credit Agreement	Jun. 30, 2013 Revolving commitments	Jun. 15, 2012 Term Loan
Financing Arrangements
Debt instrument, term								5 years
Face amount of term loan								$ 100,000,000
Maximum borrowing capacity			75,000,000				75,000,000
Fixed charge coverage ratio						1.6
Minimum fixed charge coverage ratio required to be maintained						1.25
Amount borrowed			0				0
Outstanding letters of credit			19,800,000	22,300,000
Remaining borrowing capacity			55,200,000	73,100,000
Available liquidity required to be maintained until a new collective bargaining agreement is in place			50,000,000
Available liquidity maintained under the terms of the debt arrangement			173,700,000
Outstanding surety bonds under collateralized bond program					13,300,000
Amounts collateralized by restricted funds under letters of credit	1,901,000	9,658,000		1,900,000
Amounts collateralized by letters of credit					3,800,000
Outstanding surety bonds under uncollateralized bond programs					$ 45,200,000