CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Apr. 30, 2013	Apr. 30, 2012	Apr. 30, 2011
Cash flows from operating activities:
Net income	$ 33,293	$ 54,303	$ 58,874
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	19,004	14,017	12,671
Stock-based compensation expense	11,906	13,399	15,547
Impairment of intangible assets			880
Provision for doubtful accounts	6,748	5,732	7,650
Gain on cash surrender value of life insurance policies	(6,502)	(6,268)	(7,218)
Gain on marketable securities	(7,556)	(1,013)	(7,599)
Change in fair value of acquisition-related contingent consideration		(2,196)	(4,919)
Deferred income taxes	(176)	6,512	5,954
Change in other assets and liabilities, net of effect of acquisitions:
Deferred compensation	8,477	6,320	11,588
Receivables due from clients	(16,011)	(4,227)	(29,294)
Income taxes and other receivables	4,616	(6,664)	1,154
Prepaid expenses and other assets	750	2,194	(6,172)
Investment in unconsolidated subsidiaries	(2,110)	(1,850)	(1,862)
Income taxes payable	(3,399)	4,058	(1,686)
Accounts payable and accrued liabilities	8,494	(20,519)	40,885
Other	4,173	7,177	(819)
Net cash provided by operating activities	61,707	70,975	95,634
Cash flows from investing activities:
Purchase of property and equipment	(13,101)	(18,632)	(27,889)
Purchase of intangible assets		(325)
Cash paid for acquisitions, net of cash acquired and contingent consideration	(112,064)	(442)
Purchase of marketable securities	(50,437)	(55,718)	(65,964)
Proceeds from sales/maturities of marketable securities	51,511	43,181	28,618
Change in restricted cash	7,222	(221)	(10,007)
Payment of purchase price held back from previous acquisition		(800)
Payment of contingent consideration from acquisitions			(5,795)
Premiums on life insurance policies	(1,739)	(1,739)	(1,702)
Dividends received from unconsolidated subsidiaries	1,897	1,669	1,608
Net cash used in investing activities	(116,711)	(33,027)	(81,131)
Cash flows from financing activities:
Borrowings under life insurance policies		366	6,039
Purchase of common stock	(2,838)	(4,215)	(13,844)
Proceeds from exercise of warrants			2,983
Proceeds from issuance of common stock upon exercise of employee stock options and in connection with an employee stock purchase plan	2,134	4,371	10,084
Tax benefit from exercise of stock options	294	1,664	1,287
Payment of dividends by majority owned consolidated subsidiaries			(600)
Net cash (used in) provided by financing activities	(410)	2,186	5,949
Effect of exchange rate changes on cash and cash equivalents	(2,525)	(4,985)	7,171
Net (decrease) increase in cash and cash equivalents	(57,939)	35,149	27,623
Cash and cash equivalents at beginning of year	282,005	246,856	219,233
Cash and cash equivalents at end of year	224,066	282,005	246,856
Supplemental cash flow information:
Cash used to pay interest	4,361	4,480	4,834
Cash used to pay income taxes	$ 10,611	$ 17,916	$ 25,329