Long Term Debt (Details) (USD $)	12 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2010
Debt Instrument [Line Items]
Credit facility, additional borrowing limit	$ 250,000,000
Credit facility, borrowings outstanding	611,900,000			0
Borrowings under revolving credit facility	1,386,250,000	0	230,000,000
Voting interest in foreign subsidiaries pledged against credit facility	65.00%
Investment limit in foreign subsidiaries	75,000,000
Cash investment limit for acquisition of business	150,000,000
Maximum leverage ratio allowed under debt covenant	3.0
Minimum fixed charge coverage ratio allowed under debt covenant	3.50
Leverage ratio, actual	1.82
Fixed charge coverage ratio, actual	17.70
Credit facility, origination costs	7,900,000		1,900,000
Credit facility, periodic interest payment	5,700,000	5,800,000	3,700,000
Credit facility, average interest rate during period	1.60%	1.70%	1.80%
Maximum [Member]
Debt Instrument [Line Items]
Credit facility, variable interest rate, length of time between updates	180 days
Minimum [Member]
Debt Instrument [Line Items]
Credit facility, variable interest rate, length of time between updates	30 days
Term Loan [Member]
Debt Instrument [Line Items]
Credit facility, current maximum amount	500,000,000
Credit facility, revolving loan, repayments of principal due in 2014	25,000,000
Credit facility, revolving loan, repayments of principal due in 2015	50,000,000
Credit facility, revolving loan, repayments of principal due in 2016	50,000,000
Credit facility, revolving loan, repayments of principal due in 2017	75,000,000
Long-term Debt, Maturities, Repayments of Principal in Year Five	300,000,000
Credit facility, borrowings outstanding	500,000,000
Credit facility, term loan, interest rate at period end	1.625%
Line of Credit [Member]
Debt Instrument [Line Items]
Credit facility, current maximum amount	1,000,000,000
Credit facility, borrowings outstanding	$ 111,900,000
Credit facility, revolving loan, basis spread on federal funds effective rate	0.005%
Credit facility, revolving loan, basis spread on adjusted LIBOR	1.00%
Line of Credit [Member] | Maximum [Member]
Debt Instrument [Line Items]
Credit facility, revolving loan, commitment fees percentage	0.25%
Line of Credit [Member] | Minimum [Member]
Debt Instrument [Line Items]
Credit facility, revolving loan, commitment fees percentage	0.175%
LIBOR for Eurodollar-Based Borrowings [Member] | Line of Credit [Member] | Maximum [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	1.50%
LIBOR for Eurodollar-Based Borrowings [Member] | Line of Credit [Member] | Minimum [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	1.25%
Base Rate [Member] | Line of Credit [Member] | Maximum [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate		0.50%
Base Rate [Member] | Line of Credit [Member] | Minimum [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	0.25%