Goodwill and Other Intangible Assets (Schedule Of Intangible Assets Gross Carrying Amounts And Accumulated Amortization) (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2015
Goodwill and Other Intangible Assets [Line Items]
Goodwill	$ 377,879	$ 323,616	$ 291,200
Patents [Member]
Goodwill and Other Intangible Assets [Line Items]
Gross carrying amount	1,000	1,000
Less: accumulated amortization	800	800
Net	200	200
Capitalized Software [Member]
Goodwill and Other Intangible Assets [Line Items]
Gross carrying amount	63,000	54,000
Less: accumulated amortization	34,400	26,700
Net	28,600	27,300
Customer relationships [Member]
Goodwill and Other Intangible Assets [Line Items]
Gross carrying amount	181,900	111,900
Less: accumulated amortization	37,400	28,600
Net	144,500	83,300
Other [Member]
Goodwill and Other Intangible Assets [Line Items]
Gross carrying amount	5,400	2,800
Less: accumulated amortization	1,400	900
Net	4,000	1,900
Trade names [Member]
Goodwill and Other Intangible Assets [Line Items]
Trade names	$ 173,800	$ 119,100