Consolidated Statement of Changes in Shareholders' Equity (Parenthetical) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Common stock per share dividend amount	$ 2.80	$ 2.80	$ 2.80
Common Stock [Member] | Series C Stock Warrants [Member]
Exercise of warrants into shares of common stock		407,542
Exercise of warrants into shares of common stock		186,589
Common Stock [Member] | Series A Warrants [Member]
Exercise of warrants into shares of common stock	427,905	69,127
Exercise of warrants into shares of common stock	169,543	25,427
Retained Earnings [Member]
Common stock per share dividend amount	$ 2.80	$ 2.80	$ 2.80