Fair Value Measurements (Details) (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2014 Fund	Jun. 30, 2014 Recurring [Member]	Dec. 31, 2013 Recurring [Member]	Jun. 30, 2014 Recurring [Member] Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]	Dec. 31, 2013 Recurring [Member] Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]	Jun. 30, 2014 Recurring [Member] Significant Other Observable Inputs (Level 2) [Member]	Dec. 31, 2013 Recurring [Member] Significant Other Observable Inputs (Level 2) [Member]	Jun. 30, 2014 Recurring [Member] Significant Unobservable Inputs (Level 3) [Member]	Dec. 31, 2013 Recurring [Member] Significant Unobservable Inputs (Level 3) [Member]	Jun. 30, 2014 Nonrecurring [Member]	Dec. 31, 2013 Nonrecurring [Member]	Jun. 30, 2014 Nonrecurring [Member] Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]	Dec. 31, 2013 Nonrecurring [Member] Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]	Jun. 30, 2014 Nonrecurring [Member] Significant Other Observable Inputs (Level 2) [Member]	Dec. 31, 2013 Nonrecurring [Member] Significant Other Observable Inputs (Level 2) [Member]	Jun. 30, 2014 Nonrecurring [Member] Significant Unobservable Inputs (Level 3) [Member]	Dec. 31, 2013 Nonrecurring [Member] Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Number of mutual funds that invest in debt securities or loans that qualify for credit under the Community Reinvestment Act	2
Redemption notice required to be given to convert capital account, number of days	60 days
Investment securities available-for-sale [Abstract]
U.S. Treasury notes		$ 60,721	$ 12,894	$ 60,721	$ 12,894	$ 0	$ 0	$ 0	$ 0
U.S. Agency notes		117,322	106,675	0	0	117,322	106,675	0	0
U.S. Agency mortgage-backed securities		42,150	40,309	0	0	42,150	40,309	0	0
Certificates of deposit with other banks		3,093	1,501	0	0	3,093	1,501	0	0
Municipal securities:
Non-taxable		84,737	75,333	0	0	84,737	75,333	0	0
Taxable		15,457	17,309	0	0	15,457	17,309	0	0
Mutual funds		2,419	2,380	1,419	1,380	1,000	1,000	0	0
Trust preferred securities		49	147	49	147	0	0	0	0
Equity securities		1,792	1,693	1,792	1,693	0	0	0	0
Total recurring fair value measurements		327,740	258,241	63,981	16,114	263,759	242,127	0	0
Nonrecurring fair value measurements:
Impaired loans										5,323	8,530	0	0	478	773	4,845	7,757
Other real estate owned and repossessed assets										1,906	1,463	0	0	1,906	1,463	0	0
Total nonrecurring fair value measurements										$ 7,229	$ 9,993	$ 0	$ 0	$ 2,384	$ 2,236	$ 4,845	$ 7,757