Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Feb. 28, 2019	Feb. 28, 2018
CASH FLOWS FROM OPERATING ACTIVITIES
Net income	$ 168,998	$ 123,516
Adjustments to reconcile net income to net cash provided by operating activities
Depreciation and amortization	29,052	28,372
Stock-based compensation expense	16,140	15,420
Deferred income taxes	1,088	2,934
Loss on sale of assets	196	25
Changes in assets and liabilities, net of effects of acquisitions
Accounts receivable, net of reserves	(19,676)	(16,307)
Accounts payable and accrued expenses	(5,423)	147
Accrued compensation	(26,266)	(23,595)
Deferred fees	9,729	18,098
Taxes payable, net of prepaid taxes	(17,385)	17,166
Prepaid expenses and other assets	(10,327)	(11,915)
Deferred rent and other non-current liabilities	(646)	(186)
Other working capital accounts, net	74	14
Net cash provided by operating activities	145,554	153,689
CASH FLOWS FROM INVESTING ACTIVITIES
Purchases of investments	(7,927)	(9,487)
Proceeds from maturity of investments	10,041	9,872
Purchases of property, equipment and leasehold improvements, net of proceeds from dispositions	(21,482)	(12,375)
Net cash used in investing activities	(19,368)	(11,990)
CASH FLOWS FROM FINANCING ACTIVITIES
Dividend payments	(48,442)	(43,406)
Repurchases of common stock	(110,739)	(113,906)
Other financing activities		442
Proceeds from employee stock plans	43,362	48,784
Net cash used by financing activities	(115,819)	(108,086)
Effect of exchange rate changes on cash and cash equivalents	(655)	5,284
Net increase in cash and cash equivalents	9,712	38,897
Cash and cash equivalents at beginning of period	208,623	194,731
Cash and cash equivalents at end of period	$ 218,335	$ 233,628