Consolidated Balance Sheets Parenthetical - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Statement of Financial Position [Abstract]
Investment securities available-for-sale at amortized cost	$ 1,018,774	$ 1,161,633
Fair Value	$ 68,595	$ 73,781
Preferred stock, par value (in dollars per shares)	$ 1	$ 1
Preferred Stock, Shares Authorized	2,000,000	2,000,000
Preferred stock dividend rate	6.95%	6.95%
Preferred Stock, Shares Issued	0	50,000
Preferred Stock, Shares Outstanding	0	50,000
Preferred stock, liquidation preference (in dollars per share)	$ 1,000	$ 1,000
Common Stock, Par Value Per Share	$ 1	$ 1
Common stock, shares authorized (in shares)	170,000,000	170,000,000
Common stock, shares issued (in shares)	83,655,651	84,208,538
Common stock, shares outstanding (in shares)	83,655,651	84,208,538