Summary of Financial Information by Reportable Segment and Product Line (Detail) - USD ($) $ in Thousands	12 Months Ended
	Aug. 31, 2016	Aug. 31, 2015	Aug. 31, 2014
Segment Reporting Information [Line Items]
Net sales	$ 1,149,410	$ 1,249,254	$ 1,399,862
Operating profit (loss)	(100,217)	53,554	203,108
Depreciation and amortization	47,777	53,239	60,635
Capital Expenditure	20,209	22,516	41,857
Assets	1,442,538	1,636,917
Integrated Solutions [Member]
Segment Reporting Information [Line Items]
Net sales	44,985	47,294	52,962
Industrial Tools [Member]
Segment Reporting Information [Line Items]
Net sales	314,832	355,170	360,940
Industrial
Segment Reporting Information [Line Items]
Net sales	359,817	402,464	413,901
Operating profit (loss)	79,773	105,652	120,250
Depreciation and amortization	8,175	8,257	7,597
Capital Expenditure	2,570	1,249	3,349
Assets	308,222	293,738
Energy Maintenance & Integrity [Member]
Segment Reporting Information [Line Items]
Net sales	278,881	246,357	267,500
Other Energy Solutions [Member]
Segment Reporting Information [Line Items]
Net sales	113,849	165,518	194,869
Energy
Segment Reporting Information [Line Items]
Net sales	392,731	411,875	462,368
Operating profit (loss)	(107,528)	(41,351)	56,412
Depreciation and amortization	21,944	26,532	33,983
Capital Expenditure	9,355	11,864	26,787
Assets	479,169	601,521
On-Highway [Member]
Segment Reporting Information [Line Items]
Net sales	209,575	220,889	272,201
Agriculture, Off-Highway and Other [Member]
Segment Reporting Information [Line Items]
Net sales	187,287	214,026	251,391
Engineered Solutions
Segment Reporting Information [Line Items]
Net sales	396,862	434,915	523,592
Operating profit (loss)	(42,991)	19,789	55,430
Depreciation and amortization	15,910	16,652	17,602
Capital Expenditure	5,974	8,472	8,763
Assets	493,840	588,200
General Corporate
Segment Reporting Information [Line Items]
Operating profit (loss)	(29,471)	(30,536)	(28,984)
Depreciation and amortization	1,749	1,798	1,453
Capital Expenditure	2,310	931	$ 2,958
Assets	$ 161,307	$ 153,458