Balance Sheet Information - Balance Sheet Information (Detail) (USD $) In Thousands, unless otherwise specified	Aug. 31, 2012	Aug. 31, 2011
Accounts receivable
Allowances for doubtful accounts	$ 5,847	$ 4,435
FIFO:
Finished products	87,134	74,994
Work in process	54,604	53,941
Raw materials	38,464	37,993
FIFO, Total	180,202	166,928
LIFO reserve, U.S. inventories	(17,489)	(15,465)
Inventories, net	162,713	151,463
Inventories at FIFO	128,293	121,625
Property, plant and equipment
Land	10,670	11,593
Buildings	87,237	83,075
Machinery and equipment	317,739	307,828
Property, plant and equipment, gross	415,646	402,496
Less accumulated depreciation	(245,910)	(236,870)
Property, plant and equipment, net	169,736	165,626
Accrued expenses
Employee compensation and payroll taxes	23,232	24,708
Customer advances	25,797	23,684
Pension benefits	2,777	3,045
Warranty costs	6,320	6,853
Accrued restructuring		1,074
Income taxes	9,250	4,923
Commissions	4,459	3,967
Other	24,996	20,310
Accrued expenses, total	98,299	90,159
Other long-term liabilities
German pension liability	2,777	3,045
Other long-term liabilities, total	102,056	108,391
UNITED STATES
Accrued expenses
Pension benefits	13,104	25,361
Other long-term liabilities
German pension liability	13,104	25,361
GERMANY
Accrued expenses
Pension benefits	48,955	45,486
Other long-term liabilities
German pension liability	48,955	45,486
UNITED KINGDOM
Accrued expenses
Pension benefits	5,631	2,833
Other long-term liabilities
German pension liability	5,631	2,833
Other Countries [Member]
Accrued expenses
Pension benefits	9,091	11,253
Other long-term liabilities
German pension liability	9,091	11,253
Defined Benefit Postretirement [Member] | UNITED STATES
Accrued expenses
U.S. other postretirement benefits	1,468	1,595
Other long-term liabilities
U.S. other postretirement benefits	1,468	1,595
Defined Benefit Pension [Member] | UNITED STATES
Accrued expenses
U.S. other postretirement benefits	25,275	23,458
Other long-term liabilities
U.S. other postretirement benefits	$ 25,275	$ 23,458