Capital Stock (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Feb. 28, 2017	Feb. 29, 2016	Feb. 28, 2017	Feb. 29, 2016
Earnings Per Share [Abstract]
Net earnings (loss)	$ 5,074	$ (159,190)	$ 10,039	$ (143,742)
Weighted average common shares outstanding - basic	59,368	58,991	59,170	59,089
Incremental Common Shares Attributable to Dilutive Effect of Conversion of Debt Securities	778	0	711	0
Diluted	60,146	58,991	59,881	59,089
Basic	$ 0.09	$ (2.70)	$ 0.17	$ (2.43)
Diluted	$ 0.08	$ (2.70)	$ 0.17	$ (2.43)
Anti-dilutive securities from stock based compensation plans (excluded from earnings per share calculation)	2,011	5,146	1,987	5,146