Other Comprehensive Income (Loss) (Schedule of Changes in AOCL by Component) (Details) - USD ($)	3 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Accumulated Other Comprehensive Income (Loss) [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	$ 8,800,000
Other comprehensive income (loss)
Other Comprehensive Income (Loss), Net of Tax, Total	36,900,000	$ 21,200,000
Accumulated other comprehensive loss
Beginning balance	1,726,100,000
Net activity	36,900,000	21,200,000
Ending balance	1,763,100,000
Income Tax Expense (Benefit)	12,800,000	2,800,000
Net Income (Loss) Attributable to Parent	58,800,000	39,800,000
Available-for-sale Securities and Hedges [Member]
Other comprehensive income (loss)
Prior to reclassification	(3,000,000.0)	(4,200,000)
Reclassification from	(3,400,000)	900,000
Pre-tax	(6,400,000)	(3,300,000)
Tax effect	1,500,000	700,000
Other Comprehensive Income (Loss), Net of Tax, Total	(4,900,000)	(2,600,000)
Accumulated other comprehensive loss
Beginning balance	(29,300,000)	7,200,000
Net activity	(4,900,000)	(2,600,000)
Ending balance	(34,200,000)	4,600,000
Net Income (Loss) Attributable to Parent	2,600,000	(600,000)
Foreign Currency Translation Adjustment [Member]
Other comprehensive income (loss)
Prior to reclassification	41,300,000	23,100,000
Reclassification from	0	0
Pre-tax	41,300,000	23,100,000
Tax effect	0	0
Other Comprehensive Income (Loss), Net of Tax, Total	41,300,000	23,100,000
Accumulated other comprehensive loss
Beginning balance	(110,700,000)	(145,400,000)
Net activity	41,300,000	23,100,000
Ending balance	(69,400,000)	(122,300,000)
Change in Pension and Postretirement Defined Benefit Plans [Member]
Other comprehensive income (loss)
Prior to reclassification	(500,000)	(200,000)
Reclassification from	1,200,000	1,200,000
Pre-tax	700,000	1,000,000.0
Tax effect	200,000	300,000
Other Comprehensive Income (Loss), Net of Tax, Total	500,000	700,000
Accumulated other comprehensive loss
Beginning balance	(40,200,000)	(44,300,000)
Net activity	500,000	700,000
Ending balance	(39,700,000)	(43,600,000)
Income Tax Expense (Benefit)	(200,000)	(300,000)
Change in Pension and Postretirement Defined Benefit Plans [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Accumulated other comprehensive loss
Net Income (Loss) Attributable to Parent	(1,000,000.0)	(900,000)
Accumulated Other Comprehensive Income (Loss) [Member]
Other comprehensive income (loss)
Prior to reclassification	37,800,000	18,700,000
Reclassification from	(2,200,000)	2,100,000
Pre-tax	35,600,000	20,800,000
Tax effect	1,300,000	400,000
Other Comprehensive Income (Loss), Net of Tax, Total	36,900,000	21,200,000
Accumulated other comprehensive loss
Beginning balance	(180,200,000)	(182,500,000)
Net activity	36,900,000	21,200,000
Ending balance	(143,300,000)	(161,300,000)
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent
Other comprehensive income (loss)
Reclassification from	3,400,000	(900,000)
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent | Reclassification out of Accumulated Other Comprehensive Income [Member]
Accumulated other comprehensive loss
Income Tax Expense (Benefit)	800,000	(300,000)
Foreign Exchange Forward [Member] | Available-for-sale Securities and Hedges [Member]
Other comprehensive income (loss)
Pre-tax	(2,200,000)	(200,000)
Other Comprehensive Income (Loss), Net of Tax, Total	(1,700,000)	(200,000)
Accumulated other comprehensive loss
Beginning balance	(300,000)	200,000
Net activity	(1,700,000)	(200,000)
Ending balance	(2,000,000.0)	0
Foreign Exchange Forward [Member] | Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent
Other comprehensive income (loss)
Tax effect	(500,000)	0
Interest Rate Swap [Member] | Available-for-sale Securities and Hedges [Member]
Other comprehensive income (loss)
Pre-tax	5,400,000	1,700,000
Other Comprehensive Income (Loss), Net of Tax, Total	4,200,000	1,300,000
Accumulated other comprehensive loss
Beginning balance	(35,700,000)	(5,200,000)
Net activity	4,200,000	1,300,000
Ending balance	(31,500,000)	(3,900,000)
Interest Rate Swap [Member] | Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent
Other comprehensive income (loss)
Prior to reclassification	8,000,000.0	900,000
Reclassification from	2,600,000	(800,000)
Tax effect	1,200,000	400,000
Accumulated other comprehensive loss
Income Tax Expense (Benefit)	600,000	(200,000)
Net Income (Loss) Attributable to Parent	(2,000,000.0)	600,000
Currency Swap [Member] | Available-for-sale Securities and Hedges [Member]
Accumulated other comprehensive loss
Beginning balance	6,700,000	12,200,000
Currency Swap [Member] | Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent
Other comprehensive income (loss)
Prior to reclassification	(9,600,000)	(4,800,000)
Reclassification from	0	0
Tax effect	(2,200,000)	(1,100,000)
Foreign Exchange Contract [Member] | Available-for-sale Securities and Hedges [Member]
Other comprehensive income (loss)
Pre-tax	(9,600,000)	(4,800,000)
Other Comprehensive Income (Loss), Net of Tax, Total	(7,400,000)	(3,700,000)
Accumulated other comprehensive loss
Net activity	(7,400,000)	(3,700,000)
Ending balance	(700,000)	8,500,000
Foreign Exchange | Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent
Other comprehensive income (loss)
Prior to reclassification	(1,400,000)	(300,000)
Reclassification from	800,000	(100,000)
Accumulated other comprehensive loss
Income Tax Expense (Benefit)	200,000	(100,000)
Net Income (Loss) Attributable to Parent	$ (600,000)	$ 0