Derivative Financial Instruments (Notional Amounts of Outstanding Forward Contracts (Details) - Foreign Exchange Forward [Member] - USD ($) $ in Thousands	Sep. 30, 2019	Sep. 30, 2018
Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative, notional amount	$ 498,355	$ 405,956
Not Designated as Hedging Instrument [Member] | Canadian / U.S. Dollar
Derivative [Line Items]
Derivative, notional amount	9,408	7,334
Not Designated as Hedging Instrument [Member] | Euro / U.S. Dollar
Derivative [Line Items]
Derivative, notional amount	308,282	297,730
Not Designated as Hedging Instrument [Member] | British Pound / U.S. Dollar
Derivative [Line Items]
Derivative, notional amount	3,756	7,074
Not Designated as Hedging Instrument [Member] | Israeli Sheqel / U.S. Dollar
Derivative [Line Items]
Derivative, notional amount	10,272	9,778
Not Designated as Hedging Instrument [Member] | Japanese Yen / U.S. Dollar
Derivative [Line Items]
Derivative, notional amount	37,462	37,456
Not Designated as Hedging Instrument [Member] | Swiss Franc / U.S. Dollar
Derivative [Line Items]
Derivative, notional amount	12,001	11,944
Not Designated as Hedging Instrument [Member] | Swedish Krona / U.S. Dollar
Derivative [Line Items]
Derivative, notional amount	20,636	18,207
Not Designated as Hedging Instrument [Member] | Chinese Yuan offshore / U.S. Dollar
Derivative [Line Items]
Derivative, notional amount	43,387	116
Not Designated as Hedging Instrument [Member] | Singapore Dollar / U.S. Dollar
Derivative [Line Items]
Derivative, notional amount	34,585	1,314
Not Designated as Hedging Instrument [Member] | Chinese Renminbi / U.S. Dollar
Derivative [Line Items]
Derivative, notional amount	9,079	9,010
Not Designated as Hedging Instrument [Member] | All other
Derivative [Line Items]
Derivative, notional amount	9,487	5,993
Net Investment Hedging [Member] | Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative, notional amount	183,396	0
Net Investment Hedging [Member] | Designated as Hedging Instrument [Member] | Euro / U.S. Dollar
Derivative [Line Items]
Derivative, notional amount	183,396	0
Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative, notional amount	0	12,396
Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member] | Euro / U.S. Dollar
Derivative [Line Items]
Derivative, notional amount	0	8,495
Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member] | Japanese Yen / U.S. Dollar
Derivative [Line Items]
Derivative, notional amount	0	2,193
Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member] | Swedish Krona / U.S. Dollar
Derivative [Line Items]
Derivative, notional amount	$ 0	$ 1,708