v2.4.0.8
Equity - Narrative (Details)
6 Months Ended
Jun. 30, 2014
5.0% Cumulative Convertible Preferred Stock Series Two Thousand And Five B [Member]
 
Schedule of Capitalization, Equity [Line Items]  
Preferred Stock, Dividend Rate, Percentage 5.00%
4.50% Cumulative Convertible Preferred Stock [Member]
 
Schedule of Capitalization, Equity [Line Items]  
Preferred Stock, Dividend Rate, Percentage 4.50%
5.75% Cumulative Convertible Preferred Stock [Member]
 
Schedule of Capitalization, Equity [Line Items]  
Preferred Stock, Dividend Rate, Percentage 5.75%