Preferred Stock Without Mandatory Redemption Requirement - Additional Information (Details) (USD $)
In Thousands, unless otherwise specified
12 Months Ended
Dec. 31, 2013
Dec. 31, 2012
Dec. 31, 2011
Preferred stock, dividend rate, percentage   4.50%  
Preferred stock without mandatory redemption requirements $ 0 $ 1,720  
Dividends issued $ 19 $ 153 $ 224