Consolidated Balance Sheets (Parenthetical) - USD ($) shares in Thousands, $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Securities available-for-sale, amortized cost	$ 2,004,728	$ 2,087,069
Less: unearned income on loans	$ (45,436)	$ (59,374)
Common stock, par value	$ 0	$ 0
Authorized shares	115,000	63,033
Common stock, shares outstanding	57,729	57,437