Income Taxes (Details 3) (USD $)	12 Months Ended
	Dec. 31, 2012		Dec. 31, 2011		Dec. 31, 2010
Series A Preferred Stock [Member]
Income Taxes [Line Items]
Dividend income (in dollars per share)	$ 0		$ 0		$ 0
Dividend income, percent	0.00%		0.00%		0.00%
Return of capital (in dollars per share)	$ 5.3625	[1]	$ 1.9500	[2]	$ 0
Return of capital, percent	100.00%		100.00%		0.00%
Dividends paid (in dollars per share)	$ 5.3625000		$ 1.95000		$ 0
Dividends paid, percent	100.00%		100.00%		0.00%
Series C Preferred Stock [Member]
Income Taxes [Line Items]
Dividend income (in dollars per share)	$ 0		$ 0		$ 0
Dividend income, percent	0.00%		0.00%		0.00%
Return of capital (in dollars per share)	$ 5.50	[1]	$ 2	[2]	$ 0
Return of capital, percent	100.00%		100.00%		0.00%
Dividends paid (in dollars per share)	$ 5.5000		$ 2		$ 0
Dividends paid, percent	100.00%		100.00%		0.00%

[1] Fourth quarter 2011 preferred distributions were paid January 31, 2012, and were treated as 2012 distributions for tax purposes.

[2] Fourth quarter 2010 preferred distributions were paid January 31, 2011, and were treated as 2011 distributions for tax purposes.