Investments (Gross Unrealized Losses and Fair Value by Length of Time for Held-To-Maturity Securities) (Details) (Held-to-Maturity Securities [Member], USD $) In Thousands, unless otherwise specified	Sep. 30, 2014 security	Dec. 31, 2013 security
Gain (Loss) on Investments [Line Items]
Number of securities	65	121
Fair Value	$ 115,467	$ 153,921
Less than 12 months	55	10,193
More than 12 months	2,653	387
Total Unrealized Losses	2,708	10,580
U.S. Government Agency [Member]
Gain (Loss) on Investments [Line Items]
Number of securities	8	8
Fair Value	62,526	59,678
Less than 12 months		4,827
More than 12 months	1,984
Total Unrealized Losses	1,984	4,827
State and Municipal [Member]
Gain (Loss) on Investments [Line Items]
Number of securities	57	113
Fair Value	52,941	94,243
Less than 12 months	55	5,366
More than 12 months	669	387
Total Unrealized Losses	$ 724	$ 5,753