Stockholders' Equity (Details 4)	1 Months Ended
	Mar. 31, 2012 Y	Mar. 01, 2011 Y
Monte Carlo Model [Member]
Calculation of simulated TSR's under the Monte Carlo model for the Remaining Measurement Period
Weighted average risk free rate of return (a)	0.38%	1.07%
Remaining measurement period (years)	2.82	2.83
Monte Carlo Model [Member] | Parent Company [Member]
Calculation of simulated TSR's under the Monte Carlo model for the Remaining Measurement Period
Dividend yield
Expected volatility	38.26%	61.50%
Peer Companies [Member] | Maximum [Member]
Calculation of simulated TSR's under the Monte Carlo model for the Remaining Measurement Period
Expected volatility	74.80%	113.40%
Peer Companies [Member] | Minimum [Member]
Calculation of simulated TSR's under the Monte Carlo model for the Remaining Measurement Period
Expected volatility	28.30%	38.20%