(Loss) Earnings per Share (Tables)

12 Months Ended

Dec. 31, 2012

Earnings Per Share [Abstract]

Schedule of earnings per share, basic and diluted

	Years Ended December 31,
	2012			2011			2010
(In thousands, except share and per share amounts)	(Revised)
Net (loss) income attributable to Molycorp stockholders	$	(481,169	)	$	117,526		$	(50,774	)
Dividends on Convertible Preferred Stock	(11,385		)	(9,962		)	—
(Loss) income attributable to common stockholders	(492,554		)	107,564			(50,774		)
Weighted average common shares outstanding—basic	107,064,892			83,454,221			62,332,054
Basic (loss) earnings per share	$	(4.60	)	$	1.29		$	(0.81	)
(Loss) income attributable to common stockholders	$	(492,554	)	$	107,564		$	(50,774	)
Effect of dilutive 3.25% Convertible Notes	—			413			—
(Loss) income attributable to common stockholders adjusted for effect of dilution	(492,554		)	107,977			(50,774		)
Weighted average common shares outstanding—diluted	107,064,892			85,220,017			62,332,054
Diluted (loss) earnings per share	$	(4.60	)	$	1.27		$	(0.81	)