Declaration of Dividends (Details) (USD $)	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Declaration of Dividends [Abstract]
Dividends on common stock (in dollars per share)	$ 0.07	$ 0.07
Dividends payable recorded date	Mar. 15, 2013
Dividends payable declared date	Jan. 31, 2013
Dividends payable, date to be paid	Apr. 01, 2013
Dividends Payable [Line Items]
Dividends payable recorded date	Mar. 15, 2013
Dividends payable, date to be paid	Apr. 01, 2013
Series C Preferred Stock [Member]
Declaration of Dividends [Abstract]
Dividends payable recorded date	Apr. 01, 2013
Dividends payable, date to be paid	Apr. 15, 2013
Dividends Payable [Line Items]
Preferred stock dividend rate (in hundredth)	1.00%
Dividends payable recorded date	Apr. 01, 2013
Dividends payable, date to be paid	Apr. 15, 2013