Equities Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended
	Nov. 30, 2017	Nov. 30, 2016
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	$ 7,905,825
Other comprehensive income (loss), net of tax	5,225	$ (14,494)
Ending Balance	7,937,775
Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	(135,046)	(165,146)
Other Comprehensive Income (Loss), before Reclassifications, before Tax	0	0
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax	6,816	5,250
Other Comprehensive Income (Loss), before Tax	6,816	5,250
Other Comprehensive Income (Loss), Tax	(2,620)	(2,011)
Other comprehensive income (loss), net of tax	4,196	3,239
Ending Balance	(130,850)	(161,907)
Accumulated Net Investment Gain (Loss) Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	10,041	5,656
Other Comprehensive Income (Loss), before Reclassifications, before Tax	4,044	1,259
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax	0	0
Other Comprehensive Income (Loss), before Tax	4,044	1,259
Other Comprehensive Income (Loss), Tax	(404)	(482)
Other comprehensive income (loss), net of tax	3,640	777
Ending Balance	13,681	6,433
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	(6,954)	(9,196)
Other Comprehensive Income (Loss), before Reclassifications, before Tax	(435)	620
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax	429	440
Other Comprehensive Income (Loss), before Tax	(6)	1,060
Other Comprehensive Income (Loss), Tax	2	(406)
Other comprehensive income (loss), net of tax	(4)	654
Ending Balance	(6,958)	(8,542)
Accumulated Foreign Currency Adjustment Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	(51,711)	(43,040)
Other Comprehensive Income (Loss), before Reclassifications, before Tax	(1,008)	(18,940)
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax	(2,042)	(15)
Other Comprehensive Income (Loss), before Tax	(3,050)	(18,955)
Other Comprehensive Income (Loss), Tax	443	(209)
Other comprehensive income (loss), net of tax	(2,607)	(19,164)
Ending Balance	(54,318)	(62,204)
Accumulated Other Comprehensive Income (Loss) [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	(183,670)	(211,726)
Other Comprehensive Income (Loss), before Reclassifications, before Tax	2,601	(17,061)
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax	5,203	5,675
Other Comprehensive Income (Loss), before Tax	7,804	(11,386)
Other Comprehensive Income (Loss), Tax	(2,579)	(3,108)
Other comprehensive income (loss), net of tax	5,225	(14,494)
Ending Balance	$ (178,445)	$ (226,220)