Earnings Per Share (Outstanding Common Stock Equivalents That Were Anti-Dilutive) (Parenthetical) (Detail) (USD $)	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Options Weighted Average Exercise Price	$ 2.16	$ 3.74
Exercise price for warrants outstanding	$ 22.50	$ 22.5
3 1/2% Convertible Notes [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Convertible senior notes interest percentage	3.50%	3.50%