Consolidated Statements of Financial Position (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Held-to-maturity, fair value	$ 512,705	$ 315,740
Preferred stock, no par value	$ 0	$ 0
Preferred stock, shares authorized	2,000,000	200,000
Preferred stock, shares issued	0	0
Common stock, par value	$ 1	$ 1
Common stock, shares authorized	60,000,000	45,000,000
Common Stock, Shares Issued	38,167,861	32,774,420
Common stock, shares outstanding	38,167,861	32,774,420