Consolidated Statements of Comprehensive Earnings - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2015
Comprehensive earnings
Net earnings	$ 200,507	$ 180,838	$ 181,452
Other comprehensive earnings:
Foreign currency translation adjustments	45	(6,615)	(34,989)
Net gain (loss) on foreign currency transactions designated as hedges of net investments in a foreign subsidiaries	(1,942)	792	572
Taxes on changes in foreign currency translation adjustments	588	1,462	1,988
Foreign currency translation and transactions adjustments, net of tax	(1,309)	(4,361)	(32,429)
Reclassification of net realized (gains) losses on derivatives to earnings	(72)	21	99
Taxes on changes in derivative transactions	28	(8)	(38)
Derivative adjustments, net of tax	(44)	13	61
Minimum retirement benefit liability adjustments:
Net gain (loss) arising during the period	22,979	(19,718)	(26,866)
Loss (gain) due to settlement or curtailment arising during the period		47
Amortization of net prior service cost (benefit)	(3,470)	226	225
Amortization of net loss	2,570	1,694	513
Foreign currency exchange rate changes on minimum retirement benefit liabilities	(43)	2,239	867
Taxes on changes in minimum retirement benefit liability adjustments	(8,164)	5,613	9,704
Pension and other postretirement benefit plan adjustments, net of tax	13,872	(9,899)	(15,557)
Total comprehensive earnings	$ 213,026	$ 166,591	$ 133,527