LONG-TERM DEBT (Details) (USD $)	12 Months Ended								1 Months Ended	3 Months Ended	1 Months Ended		3 Months Ended						1 Months Ended		1 Months Ended
	Jun. 30, 2011	Sep. 30, 2011	Sep. 30, 2011 Revolving credit facility	Jun. 30, 2011 Revolving credit facility	Sep. 30, 2011 Term loan facility	Jun. 30, 2011 Term loan facility	Sep. 30, 2011 Other, generally unsecured	Jun. 30, 2011 Other, generally unsecured	Apr. 30, 2011 New Credit Facility	Sep. 30, 2011 New Credit Facility	Apr. 30, 2011 New Credit Facility, term loan	Apr. 15, 2011 New Credit Facility, term loan Y	Sep. 30, 2011 New Credit Facility, term loan Quarterly principal reduction through March 2013	Sep. 30, 2011 New Credit Facility, term loan Quarterly principal reduction from June 2013 through March 2014	Sep. 30, 2011 New Credit Facility, term loan Quarterly principal reduction from June 2014 through May 2016	Sep. 30, 2011 New Credit Facility, term loan Principal reduction May 2016	Sep. 30, 2011 New Credit Facility, revolving credit	Apr. 15, 2011 New Credit Facility, revolving credit Y	Sep. 30, 2012 Interest rate swap agreement maturing on September 26, 2012	Sep. 26, 2012 Interest rate swap agreement maturing on September 26, 2012	Jun. 30, 2011 Interest rate swap agreement maturing on May 13, 2016
Components of long-term debt
Long-term debt	$ 515,403,000	$ 506,665,000	$ 214,000,000	$ 219,000,000	$ 292,500,000	$ 296,250,000	$ 165,000	$ 153,000
Less current maturities	(15,153,000)	(15,165,000)
Long-term debt, net of current maturities	500,250,000	491,500,000
Overall capacity of senior secured credit facility									700,000,000		300,000,000
Maximum borrowing capacity																		400,000,000
Total undrawn revolver capacity																	186,000,000
Term of facility (in years)												5						5
Sublimit under the revolving credit facility related to standby letters of credit																		50,000,000
Sublimit under the revolving credit facility related to swingline loans																		10,000,000
Sublimit under the revolving credit facility related to multicurrency borrowings																		150,000,000
Variable rate basis										LIBOR
Debt, margin on LIBOR rate, low end of range (as a percent)										1.25%
Debt, margin on LIBOR rate, high end of range (as a percent)										2.00%
Variable interest rate description before hedging of debt	LIBOR																		LIBOR		LIBOR
Notional amount of interest rate swap		292,500,000																		218,800,000	165,000,000
Effective interest rate for hedged variable rate debt (as a percent)																			1.89%		2.09%
Effective interest rate after giving effect to the floating-to-fixed interest rate swaps (as a percent)			3.82%		1.97%
Quarterly principal reductions, percentage of original principal amount (as a percent)													1.25%	1.875%	2.50%
Principal reduction amount													$ 3,750,000	$ 5,625,000	$ 7,500,000	$ 187,500,000