Investment Securities - Additional Information (Detail) (USD $)				12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2013 Preferred Stock [Member]
Investment Securities [Line Items]
Stock purchased				730,000
REIT market capitalization value	$ 1,500,000,000
Investment securities		$ 0	$ 0