Pension and Post-retirement Benefits (Tables)

6 Months Ended

Mar. 31, 2019

Pension and Post-retirement Benefits

Schedule of components of net periodic pension and postretirement benefit cost

	Three Months Ended March 31,								Six Months Ended March 31,
	Pension Benefits				Other Benefits				Pension Benefits				Other Benefits
	2018		2019		2018		2019		2018		2019		2018		2019
Service cost	$	1,384	$	1,310	$	84	$	79	$	2,768	$	2,620	$	168	$	158
Interest cost		2,625		2,567		1,078		1,088		5,231		5,133		2,156		2,176
Expected return		(3,665)		(3,575)		—		—		(7,299)		(7,147)		—		—
Amortizations		1,294		401		751		372		2,583		803		1,500		744
Net periodic benefit cost	$	1,638	$	703	$	1,913	$	1,539	$	3,283	$	1,409	$	3,824	$	3,078