Earnings Per Share - Additional Information (Detail) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Weighted Average number of shares outstanding dilutive effect		3
Number of weighted average outstanding diluted shares	1,101	1,169
5.25% Convertible Notes, Due 2014 [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Number of shares, option exercised	89
Number of shares that become outstanding	89
Number of weighted average outstanding shares included in both basic and diluted shares	23
Weighted Average number of shares outstanding dilutive effect	89
Number of weighted average outstanding diluted shares	66
Convertible Notes [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares that would have been included in diluted earnings per share calculation	66
Number of anti-dilutive securities	66
Stock Awards [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares that would have been included in diluted earnings per share calculation	18
Number of anti-dilutive securities	10
Stock Option [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares that would have been included in diluted earnings per share calculation	31
Number of anti-dilutive securities	5
Weighted average exercise price of options	$ 14.53	$ 12.20
Equity Unit Purchase Agreements [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Number of anti-dilutive securities	10	31