Consolidated Statements of Changes in Equity (Unaudited) (USD $) In Thousands, unless otherwise specified	Total	Preferred Stock [Member]	Common Stock [Member]	Capital Surplus [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income [Member]	Treasury Stock [Member]	Noncontrolling Interest [Member]
Balance at beginning of period at Dec. 31, 2011	$ 352,893	$ 81,698	$ 16,612	$ 43,333	$ 198,182	$ 12,147	$ (1,754)	$ 2,675
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive Income	15,086				12,841	2,271		(26)
Cash dividends declared:
Preferred	(1,021)				(1,021)
Common	(1,649)				(1,649)
Purchase of shares of common stock	(308)						(308)
Issuance of shares of common stock	283			(207)			490
Commitments to issue common stock	759			759
Balance at end of period at Mar. 31, 2012	366,043	81,698	16,612	43,885	208,353	14,418	(1,572)	2,649
Balance at beginning of period at Dec. 31, 2012	404,539	81,698	16,828	50,359	236,279	16,641	0	2,734
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive Income	9,742				12,488	(2,810)		64
Cash dividends declared:
Preferred	(408)				(408)
Common	(1,684)				(1,684)
Purchase of shares of common stock	(258)						(258)
Issuance of shares of common stock	1,054		39	783			232
Commitments to issue common stock	989			989
Balance at end of period at Mar. 31, 2013	$ 413,974	$ 81,698	$ 16,867	$ 52,131	$ 246,675	$ 13,831	$ (26)	$ 2,798