Benefit Plans Schedule of Net Benefit Costs (Tables)

9 Months Ended

May 31, 2020

Retirement Benefits [Abstract]

Schedule of Net Benefit Costs of Assumptions Used

Components of net periodic benefit costs for the three and nine months ended May 31, 2020, and 2019, are as follows:

	Three Months Ended May 31,
	Qualified Pension Benefits						Nonqualified Pension Benefits						Other Benefits
	2020			2019			2020			2019			2020			2019
Components of net periodic benefit costs:	(Dollars in thousands)
Service cost	$	10,538		$	9,648		$	101		$	78		$	262		$	263
Interest cost	5,431			7,099			107			186			187			274
Expected return on assets	(11,671		)	(11,242		)	—			—			—			—
Prior service cost (credit) amortization	45			42			(28		)	(19		)	(111		)	(139		)
Actuarial loss (gain) amortization	5,396			3,087			25			1			(348		)	(407		)
Net periodic benefit cost	$	9,739		$	8,634		$	205		$	246		$	(10	)	$	(9	)
	Nine Months Ended May 31,
	Qualified Pension Benefits						Nonqualified Pension Benefits						Other Benefits
	2020			2019			2020			2019			2020			2019
Components of net periodic benefit costs:	(Dollars in thousands)
Service cost	$	31,613		$	28,944		$	304		$	233		$	787		$	790
Interest cost	16,292			21,297			322			560			560			821
Expected return on assets	(35,013		)	(33,726		)	—			—			—			—
Prior service cost (credit) amortization	134			127			(85		)	(56		)	(334		)	(417		)
Actuarial loss (gain) amortization	16,187			9,261			74			2			(1,044		)	(1,221		)
Settlement loss	—			169			—			—			—			—
Net periodic benefit cost	$	29,213		$	26,072		$	615		$	739		$	(31	)	$	(27	)