Acquisition Accounting - Purchase Price Allocation (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Apr. 30, 2013 Super Media, Inc.
Fair value of assets acquired
Cash and cash equivalents				$ 154
Accounts receivable				111
Unbilled accounts receivable				316
Other current assets				64
Fixed assets and capitalized software				42
Intangible assets				635
Goodwill	315	0	0	389
Pension assets				58
Other non-current assets				4
Total fair value of assets acquired				1,773
Fair value of liabilities acquired
Accounts payable and accrued liabilities				114
Long-term debt (including current maturities)				1,082
Employee benefit obligations				99
Unrecognized tax benefits				45
Deferred tax liabilities				351
Total fair value of liabilities acquired				1,691
Total allocable purchase price				$ 82