Summary of Segment Information (Detail) (USD $) In Thousands	3 Months Ended								12 Months Ended
	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010	Sep. 30, 2010	Jun. 30, 2010	Mar. 31, 2010	Dec. 31, 2009	Sep. 30, 2011		Sep. 30, 2010		Sep. 30, 2009
Segment revenues:
Transactional and maintenance									$ 453,430		$ 455,487		$ 478,702
Professional services									115,941		102,878		112,413
License									50,312		47,278		39,620
Total revenues	160,249	150,679	152,824	155,931	155,098	155,329	143,720	151,496	619,683		605,643		630,735
Segment operating expense									(456,714)		(462,471)		(469,458)
Unallocated share-based compensation expense									(15,500)		(17,305)		(19,935)
Unallocated amortization expense									(7,741)	[1]	(10,901)	[1]	(12,891)	[1]
Unallocated restructuring expense			(11,500)	(900)	(1,600)				(12,391)		(1,617)		(8,711)
Unallocated loss on sale of product line assets													(2,993)
Operating income									127,337		113,349		116,747
Unallocated interest income									2,192		1,688		4,717
Interest expense									(32,364)		(24,124)		(25,481)
Unallocated other expense, net									290		1,391		1,587
Income from continuing operations before income taxes									97,455		92,304		97,570
Depreciation expense									16,456		20,017		25,528
Applications
Segment revenues:
Transactional and maintenance									258,736		257,275		274,123
Professional services									100,921		86,097		92,000
License									23,371		23,886		17,007
Total revenues									383,028		367,258		383,130
Segment operating expense									(276,467)		(273,983)		(270,541)
Depreciation expense									12,784		14,998		19,569
Applications | Segment operating income
Segment revenues:
Operating income									106,561		93,275		112,589
Scores
Segment revenues:
Transactional and maintenance									164,918		170,141		178,048
Professional services									2,102		2,042		1,527
License									1,547		156
Total revenues									168,567		172,339		179,575
Segment operating expense									(55,169)		(61,688)		(57,373)
Depreciation expense									1,007		1,339		1,827
Scores | Segment operating income
Segment revenues:
Operating income									113,398		110,651		122,202
Tools
Segment revenues:
Transactional and maintenance									29,776		28,071		26,531
Professional services									12,918		14,739		18,886
License									25,394		23,236		22,613
Total revenues									68,088		66,046		68,030
Segment operating expense									(54,398)		(57,634)		(60,676)
Depreciation expense									1,667		2,147		2,248
Tools | Segment operating income
Segment revenues:
Operating income									13,690		8,412		7,354
Unallocated Corporate Expenses
Segment revenues:
Segment operating expense									(70,680)		(69,166)		(80,868)
Depreciation expense									998		1,533		1,884
Unallocated Corporate Expenses | Segment operating income
Segment revenues:
Operating income									(70,680)		(69,166)		(80,868)
Segment operating income
Segment revenues:
Operating income									$ 162,969		$ 143,172		$ 161,277

[1] Cost of revenues and selling, general and administrative expenses exclude the amortization of intangible assets. See Note 8 to consolidated financial statements.