Parent Company Condensed Financial Information - Condensed Balance Sheets (Details) (USD $) In Thousands, except Share data, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Condensed Financial Information of Parent Company Only Disclosure [Abstract]
Common stock, shares authorized	100,000,000	50,000,000
Common stock, par value	$ 1	$ 1
Preferred stock, shares authorized	1,000,000	1,000,000
Assets:
Cash on deposit with bank subsidiary	$ 36,125	$ 40,790
Other assets	8,327	15,011
Total Assets	1,923,438	1,993,188	2,300,594
Liabilities and Shareholders' Equity:
Other liabilities	11,892	10,738
Shareholders' equity	170,794	140,586	147,457	152,265
Total	1,923,438	1,993,188
Parent Company
Assets:
Cash on deposit with bank subsidiary	5,212	6,797
Investment in subsidiary	199,680	169,654
Other investments	1,765	1,864
Other assets	351	352
Total Assets	207,008	178,667
Liabilities and Shareholders' Equity:
Dividends payable	183	2,163
Other liabilities	36,031	35,918
Shareholders' equity	170,794	140,586
Total	$ 207,008	$ 178,667