Condensed Consolidated Statements of Comprehensive Earnings - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Comprehensive earnings
Net earnings	$ 49,120	$ 18,260
Other comprehensive earnings:
Foreign currency translation adjustments	(1,734)	5,103
Net gain (loss) on foreign currency transactions designated as hedges of net investments in foreign subsidiaries (Note 8)	649	(743)
Taxes on changes in foreign currency translation adjustments	383	187
Foreign currency translation and transactions adjustments, net of tax	(702)	4,547
Unrealized gain (loss) on fair value adjustment of derivative instruments (Note 8)	18,563
Reclassification of net realized (gains) losses on derivatives to earnings (Note 8)	(7,826)	(18)
Taxes on changes in derivative transactions	(208)	7
Derivative adjustments, net of tax	10,529	(11)
Curtailment of postretirement benefit plan arising during the period		59
Amortization of pension and other postretirement plan:
Net prior service cost	176	137
Net loss	239	246
Foreign currency exchange rate changes on pension and other postretirement benefit plan liabilities	303	(99)
Taxes on changes in pension and other postretirement benefit plan liability adjustments, net of foreign currency exchange rate changes	(209)	(132)
Pension and other postretirement benefit plan adjustments, net of tax	509	211
Total comprehensive earnings	$ 59,456	$ 23,007