XML 13 R54.htm IDEA: XBRL DOCUMENT v3.3.0.814
Shareholders' Equity - Additional Information (Detail) - $ / shares
Sep. 30, 2015
Jun. 30, 2015
Dec. 31, 2014
Class of Stock [Line Items]      
Preferred stock, shares authorized 1,000,000 1,000,000 1,000,000
Preferred stock, par value $ 1.00 $ 1.00 $ 1.00
Warrant [Member] | Series D Fixed Rate Non-Cumulative Perpetual Preferred Stock [Member]      
Class of Stock [Line Items]      
Exercise price of each class of warrants or rights outstanding $ 518.96   $ 518.96
Warrant to purchase common stock 95,383   95,383