Contingencies - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	1 Months Ended	3 Months Ended		12 Months Ended			3 Months Ended		12 Months Ended			1 Months Ended		12 Months Ended	1 Months Ended	12 Months Ended
	Apr. 30, 2011	Sep. 30, 2012	Jun. 30, 2011	Dec. 31, 2009	Dec. 31, 2012	Dec. 31, 2011	Sep. 30, 2012 Legacy Tax Matters	Jun. 30, 2011 Legacy Tax Matters	Dec. 31, 2012 Legacy Tax Matters	Dec. 31, 2009 Legacy Tax Matters IMS Health And NMR 1993 - 1996	Dec. 31, 2012 Legacy Tax Matters 1989-1990 And 1993-1996	Nov. 07, 2012 Abu Dhabi Commercial Bank Litigation Plaintiff	Aug. 31, 2012 Abu Dhabi Commercial Bank Litigation Plaintiff	Dec. 31, 2012 Abu Dhabi Commercial Bank Litigation	Feb. 01, 2013 Abu Dhabi Commercial Bank Litigation Subsequent event Plaintiff	Dec. 31, 2012 King County, Washington and Iowa Student Loan Liquidity Corporation Plaintiff
Loss Contingencies [Line Items]
Number of plaintiffs dismissed													4		1
Number of plaintiffs													11			2
Number of plaintiffs granted												2
Number of plaintiffs filed motions for reconsideration												3
Total compensatory damages value														$ 638		$ 70
Unsought claimed damages														14.5
Liabilities for 2000 Distribution Agreement and Liabilities for Legacy Tax Matters, liability for remaining potential exposure including accrued interest					39.2
Proceeds from IMS Health, NMR arbitration settlements and New D&B for 50% of the anticipated future tax benefits through 2012									55.0	10.8
Anticipated future tax benefits									50.00%
Reduction of interest expense				6.5			4.4	2.8
Reduction in interest expense, net of tax							2.6	1.7
Increase in other non-operating income							12.8	6.4
Liabilities for 2000 Distribution Agreement and Liabilities for Legacy Tax Matters, Liability for the remaining potential exposure					37.1	52.6			37.1
Legacy refund	0.9
Legacy refund, net	0.6
Benefit to net income related to the resolution of legacy tax matters		12.8	7.0							8.2
Reduction of tax expense				4.3
Liability for legacy tax matters											$ 2.1