Investment Securities, Securities Sales And Continuous Unrealized Loss Position Of Securities Held (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2013
Proceeds from sales of securities available for sale and the associated realized securities gains and losses [Abstract]
Proceeds	$ 0	$ 10,475
Gross realized gains	0	359
Gross realized losses	0	0
Net realized gains	0	359
Length of time individual securities for held-to-maturity and available-for-sale held in a continuous unrealized loss position [Abstract]
Less than 12 months Estimated Fair Value	176,404		187,007
Less than 12 months Unrealized Losses	6,883		13,001
12 months or longer Estimated Fair Value	33,702		31,855
12 months or longer Unrealized Losses	1,922		2,856
Total Estimated Fair Value	210,106		218,862
Total Unrealized Losses	8,805		15,857
U.S. Government Agency Securities [Member]
Length of time individual securities for held-to-maturity and available-for-sale held in a continuous unrealized loss position [Abstract]
Less than 12 months Estimated Fair Value	88,511		86,590
Less than 12 months Unrealized Losses	3,273		7,726
12 months or longer Estimated Fair Value	9,403		13,505
12 months or longer Unrealized Losses	597		1,494
Total Estimated Fair Value	97,914		100,095
Total Unrealized Losses	3,870		9,220
Obligations of States and Political Subdivisions [Member]
Length of time individual securities for held-to-maturity and available-for-sale held in a continuous unrealized loss position [Abstract]
Less than 12 months Estimated Fair Value			3,932
Less than 12 months Unrealized Losses			87
12 months or longer Estimated Fair Value			0
12 months or longer Unrealized Losses			0
Total Estimated Fair Value			3,932
Total Unrealized Losses			87
Collateralized Mortgage Obligations [Member]
Length of time individual securities for held-to-maturity and available-for-sale held in a continuous unrealized loss position [Abstract]
Less than 12 months Estimated Fair Value	0		2,935
Less than 12 months Unrealized Losses	0		160
12 months or longer Estimated Fair Value	8,634		5,713
12 months or longer Unrealized Losses	689		628
Total Estimated Fair Value	8,634		8,648
Total Unrealized Losses	689		788
Mortgage-Backed Securities [Member]
Length of time individual securities for held-to-maturity and available-for-sale held in a continuous unrealized loss position [Abstract]
Less than 12 months Estimated Fair Value	85,484		84,869
Less than 12 months Unrealized Losses	3,566		4,850
12 months or longer Estimated Fair Value	12,739		12,637
12 months or longer Unrealized Losses	562		734
Total Estimated Fair Value	98,223		97,506
Total Unrealized Losses	4,128		5,584
Corporate Bonds [Member]
Length of time individual securities for held-to-maturity and available-for-sale held in a continuous unrealized loss position [Abstract]
Less than 12 months Estimated Fair Value	2,409		8,681
Less than 12 months Unrealized Losses	44		178
12 months or longer Estimated Fair Value	2,926		0
12 months or longer Unrealized Losses	74		0
Total Estimated Fair Value	5,335		8,681
Total Unrealized Losses	$ 118		$ 178