Contingencies - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	1 Months Ended	9 Months Ended	12 Months Ended		1 Months Ended	12 Months Ended		9 Months Ended			3 Months Ended	9 Months Ended
	Apr. 30, 2011	Sep. 30, 2012	Dec. 31, 2009	Dec. 31, 2011	Oct. 31, 2009 King County, Washington and Iowa Student Loan Liquidity Corporation Plaintiff	Dec. 31, 2009 Legacy Tax Matters IMS Health And NMR 1993 - 1996	Sep. 30, 2012 Legacy Tax Matters 1989-1990 And 1993-1996	Sep. 30, 2012 Abu Dhabi Commercial Bank Litigation Plaintiff	Sep. 30, 2012 Abu Dhabi Commercial Bank Litigation Damages Asserted	Sep. 30, 2012 Abu Dhabi Commercial Bank Litigation Filed motions for reconsideration	Jun. 30, 2011 Legacy Tax Matters	Sep. 30, 2012 Legacy Tax Matters
Loss Contingencies [Line Items]
Loss related to application for attorney's fees and costs, maximum amount		$ 4.95
Total compensatory damages value					70			713	303	288
Number of plaintiffs dismissed								4
Number of plaintiffs					2			11
Liabilities for 2000 Distribution Agreement and Liabilities for Legacy Tax Matters, liability for remaining potential exposure including accrued interest		38.9
Proceeds from IMS Health, NMR arbitration settlements and New D&B for 50% of the anticipated future tax benefits through 2012						10.8						55.0
Liabilities for 2000 Distribution Agreement and Liabilities for Legacy Tax Matters, liability for the remaining potential exposure		36.8		52.6								36.8
Anticipated future tax benefits												50.00%
Reduction of interest expense			6.5								2.8	4.4
Reduction in interest expense, net of tax											1.7	2.6
Increase in other non-operating income											6.4	12.8
Legacy refund	0.9
Legacy refund, net	0.6
Benefit to net income related to the resolution of legacy tax matters						8.2
Reduction of tax expense			4.3
Liability for legacy tax matters							$ 2.1