CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	6 Months Ended
Feb. 28, 2015	Feb. 28, 2014
Operating activities:
Net income	$ 22,119us-gaap_NetIncomeLoss	$ 21,799us-gaap_NetIncomeLoss
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	3,247	2,849
Net gains on sales and disposals of property and equipment	(31)	(33)
Deferred income taxes	(1,046)us-gaap_DeferredIncomeTaxExpenseBenefit	(335)us-gaap_DeferredIncomeTaxExpenseBenefit
Excess tax benefits from settlements of stock-based equity awards	(587)	(820)
Stock-based compensation	1,636us-gaap_ShareBasedCompensation	1,479us-gaap_ShareBasedCompensation
Unrealized foreign currency exchange losses, net	1,745	132
Provision for bad debts	209us-gaap_ProvisionForDoubtfulAccounts	174us-gaap_ProvisionForDoubtfulAccounts
Changes in assets and liabilities:
Trade and other accounts receivable	(12,602)	(4,885)
Inventories	(408)us-gaap_IncreaseDecreaseInInventories	(1,387)us-gaap_IncreaseDecreaseInInventories
Other assets	2,332	(3,309)
Accounts payable and accrued liabilities	4,501	5,470
Accrued payroll and related expenses	(8,037)	(9,603)
Income taxes payable	318	2,744
Other long-term liabilities	100	32
Net cash provided by operating activities	13,496	14,307
Investing activities:
Purchases of property and equipment	(2,833)	(1,991)
Proceeds from sales of property and equipment	250	171
Purchases of intangible assets		(1,776)
Acquisition of business	(3,705)
Purchases of short-term investments	(1,831)	(5,643)
Maturities of short-term investments	1,673	908
Net cash used in investing activities	(6,446)	(8,331)
Financing activities:
Treasury stock purchases	(14,551)	(22,270)
Dividends paid	(10,606)us-gaap_PaymentsOfDividends	(9,973)us-gaap_PaymentsOfDividends
Proceeds from issuance of common stock	856	1,241
Excess tax benefits from settlements of stock-based equity awards	587	820
Proceeds from revolving credit facility	5,000us-gaap_ProceedsFromLinesOfCredit	10,000us-gaap_ProceedsFromLinesOfCredit
Net cash used in financing activities	(18,714)	(20,182)
Effect of exchange rate changes on cash and cash equivalents	(2,438)	1,734
Net decrease in cash and cash equivalents	(14,102)	(12,472)
Cash and cash equivalents at beginning of period	57,803	53,434
Cash and cash equivalents at end of period	$ 43,701	$ 40,962

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.