Business Segments (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
Jan. 31, 2015	Jan. 31, 2014	Jan. 31, 2015	Jan. 31, 2014
Segment Reporting Information [Line Items]
Fee revenue	$ 249,545us-gaap_SalesRevenueServicesNet	$ 242,184us-gaap_SalesRevenueServicesNet	$ 756,435us-gaap_SalesRevenueServicesNet	$ 708,589us-gaap_SalesRevenueServicesNet
Total revenue	258,871us-gaap_Revenues	250,937us-gaap_Revenues	783,913us-gaap_Revenues	734,761us-gaap_Revenues
Net income	22,939us-gaap_NetIncomeLoss	21,304us-gaap_NetIncomeLoss	62,875us-gaap_NetIncomeLoss	51,480us-gaap_NetIncomeLoss
Other loss (income), net	1,478us-gaap_OtherNonoperatingIncomeExpense	(1,132)us-gaap_OtherNonoperatingIncomeExpense	(3,061)us-gaap_OtherNonoperatingIncomeExpense	(7,751)us-gaap_OtherNonoperatingIncomeExpense
Interest (income) expense, net	(288)	873	1,426	2,102
Equity in earnings of unconsolidated subsidiaries, net	(778)	(470)	(1,696)	(1,492)
Income tax provision	9,576us-gaap_IncomeTaxExpenseBenefit	6,727us-gaap_IncomeTaxExpenseBenefit	26,392us-gaap_IncomeTaxExpenseBenefit	22,789us-gaap_IncomeTaxExpenseBenefit
Operating income	32,927us-gaap_OperatingIncomeLoss	27,302us-gaap_OperatingIncomeLoss	85,936us-gaap_OperatingIncomeLoss	67,128us-gaap_OperatingIncomeLoss
Depreciation and amortization	6,814	6,333	20,363	18,857
Other (loss) income, net	(1,478)us-gaap_NonoperatingIncomeExpense	1,132us-gaap_NonoperatingIncomeExpense	3,061us-gaap_NonoperatingIncomeExpense	7,751us-gaap_NonoperatingIncomeExpense
Equity in earnings of unconsolidated subsidiaries, net	778	470	1,696	1,492
EBITDA	39,041	35,237	111,056	95,228
Restructuring (recoveries) charges, net	(418)kfy_RestructuringIncomeExpenseNet		9,468kfy_RestructuringIncomeExpenseNet	3,682kfy_RestructuringIncomeExpenseNet
Separation costs				4,500kfy_SeparationCosts
Acquisition costs	445		445
Integration costs				394
Adjusted EBITDA	39,068	35,237	120,969	103,804
Operating Segments \| Executive Recruitment
Segment Reporting Information [Line Items]
Fee revenue	143,479	144,042	440,824	420,689
Total revenue	148,987	149,687	457,581	437,458
Operating income	33,583	31,622	87,680	88,029
Depreciation and amortization	1,593	1,620	5,048	5,398
Other (loss) income, net	(135)	254	537	1,086
Equity in earnings of unconsolidated subsidiaries, net	103	36	281	258
EBITDA	35,144	33,532	93,546	94,771
Restructuring (recoveries) charges, net	(148)		5,384	1,336
Adjusted EBITDA	34,996	33,532	98,930	96,107
Operating Segments \| Executive Recruitment \| North America
Segment Reporting Information [Line Items]
Fee revenue	78,026	77,208	243,055	226,538
Total revenue	81,521	80,926	253,855	237,771
Operating income	22,673	19,919	60,788	51,773
Depreciation and amortization	867	849	2,662	2,732
Other (loss) income, net	(225)	81	98	529
Equity in earnings of unconsolidated subsidiaries, net	103	36	281	258
EBITDA	23,418	20,885	63,829	55,292
Restructuring (recoveries) charges, net			1,151	816
Adjusted EBITDA	23,418	20,885	64,980	56,108
Operating Segments \| Executive Recruitment \| EMEA
Segment Reporting Information [Line Items]
Fee revenue	36,816	39,144	113,788	107,742
Total revenue	37,868	40,381	117,351	111,078
Operating income	5,073	6,649	13,337	18,469
Depreciation and amortization	431	452	1,366	1,339
Other (loss) income, net	24	121	69	403
EBITDA	5,528	7,222	14,772	20,211
Restructuring (recoveries) charges, net			3,987	460
Adjusted EBITDA	5,528	7,222	18,759	20,671
Operating Segments \| Executive Recruitment \| Asia Pacific
Segment Reporting Information [Line Items]
Fee revenue	20,924	20,213	61,615	63,063
Total revenue	21,874	20,820	63,959	65,087
Operating income	4,096	3,922	10,042	12,894
Depreciation and amortization	216	267	771	1,102
Other (loss) income, net	25	52	283	144
EBITDA	4,337	4,241	11,096	14,140
Restructuring (recoveries) charges, net			17	60
Adjusted EBITDA	4,337	4,241	11,113	14,200
Operating Segments \| Executive Recruitment \| South America
Segment Reporting Information [Line Items]
Fee revenue	7,713	7,477	22,366	23,346
Total revenue	7,724	7,560	22,416	23,522
Operating income	1,741	1,132	3,513	4,893
Depreciation and amortization	79	52	249	225
Other (loss) income, net	41		87	10
EBITDA	1,861	1,184	3,849	5,128
Restructuring (recoveries) charges, net	(148)		229
Adjusted EBITDA	1,713	1,184	4,078	5,128
Operating Segments \| LTC
Segment Reporting Information [Line Items]
Fee revenue	64,313	62,217	194,269	188,357
Total revenue	66,048	64,282	199,945	194,566
Operating income	8,577	5,651	19,799	16,992
Depreciation and amortization	3,317	3,272	9,848	9,330
Other (loss) income, net	(156)	92	(111)	145
EBITDA	11,738	9,015	29,536	26,467
Restructuring (recoveries) charges, net			2,758	1,149
Adjusted EBITDA	11,738	9,015	32,294	27,616
Operating Segments \| Futurestep
Segment Reporting Information [Line Items]
Fee revenue	41,753	35,925	121,342	99,543
Total revenue	43,836	36,968	126,387	102,737
Operating income	5,760	3,925	14,367	9,009
Depreciation and amortization	469	437	1,374	1,285
Other (loss) income, net	4	28	27	576
EBITDA	6,233	4,390	15,768	10,870
Restructuring (recoveries) charges, net	(270)		1,154	1,134
Adjusted EBITDA	5,963	4,390	16,922	12,004
Corporate
Segment Reporting Information [Line Items]
Operating income	(14,993)	(13,896)	(35,910)	(46,902)
Depreciation and amortization	1,435	1,004	4,093	2,844
Other (loss) income, net	(1,191)	758	2,608	5,944
Equity in earnings of unconsolidated subsidiaries, net	675	434	1,415	1,234
EBITDA	(14,074)	(11,700)	(27,794)	(36,880)
Restructuring (recoveries) charges, net			172	63
Separation costs				4,500
Acquisition costs	445		445
Integration costs				394
Adjusted EBITDA	$ (13,629)	$ (11,700)	$ (27,177)	$ (31,923)

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