Goodwill and Other Intangible Assets - Other Intangible Assets (Parenthetical) (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Finite-Lived Intangible Assets [Line Items]
Total other intangible assets, Gross carrying amount	$ 1,187	$ 1,182
Other Intangibles [Member] | Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Total other intangible assets, Gross carrying amount		$ 31