Acquisitions and Divestitures (Divestitures) (Details Textual) (USD $)	1 Months Ended	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012	Mar. 22, 2013
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Equity Method Investment, Offer to Purchase Additional Equity, Percentage	22.23%
Payments for Previous Acquisition, Financing Activities				$ 12,000,000	$ 0
Disposal Group, Including Discontinued Operation, Sale Price						2,400,000,000
Gain on sale of discontinued operations, net of tax		0	0	612,000,000	0
Unallocated Amount to Segment [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Restructuring Charges		$ 10,000,000	$ 24,000,000	$ 54,000,000	$ 53,000,000
CRISIL Limited [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Equity Method Investment, Ownership Percentage	52.77%	52.77%		52.77%
Pro Forma [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Equity Method Investment, Ownership Percentage	75.00%	75.00%		75.00%