Consolidated Balance Sheets [Parenthetical] - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Balance Sheet Parenthetical [Abstract]
Investment Securities held-to-maturity, estimated fair value (in dollars)	$ 142,260	$ 155,555
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares issued	72,792,570	72,491,850
Common stock, shares outstanding	72,792,570	72,491,850