Securities (Details) (USD $) In Thousands, unless otherwise specified	6 Months Ended
Jun. 30, 2012	Dec. 31, 2011
Amortized costs and fair value of securities held-to-maturity [Abstract]
Amortized Cost	$ 615	$ 1,515
Gross Unrecognized Holding Gain	6	11
Gross Unrecognized Holding Loss	0	0
Fair Value	621	1,526
Amortized costs and fair values of securities available-for-sale [Abstract]
Amortized Cost	293,105	234,287
Gross Unrealized Gains	3,023	2,368
Gross Unrealized Losses	(333)	(56)
Fair Value	295,795	236,599
Gross Unrealized Loss [Abstract]
Securities Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	333	56
Securities Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	0	0
Securities Available-for-sale Continuous Unrealized Loss Position, Total	333	56
Gross Unrealized Loss, Fair Value [Abstract]
Less than Twelve Months, Fair Value	38,370	31,070
Twelve Months or Longer, Fair Value	0	0
Fair Value, Total	38,370	31,070
US Treasury Securities [Member]
Amortized costs and fair values of securities available-for-sale [Abstract]
Amortized Cost		250
Gross Unrealized Gains		0
Gross Unrealized Losses		0
Fair Value		250
Obligations of US Government Agencies [Member]
Amortized costs and fair values of securities available-for-sale [Abstract]
Amortized Cost	40,676	117,848
Gross Unrealized Gains	1,164	1,706
Gross Unrealized Losses	0	0
Fair Value	41,840	119,554
Continuous Unrealized Loss Position, Qualitative Disclosure [Abstract]
Cause	caused by increases in market interest rates
Obligations of States and Political Subdivisions [Member]
Amortized costs and fair values of securities available-for-sale [Abstract]
Amortized Cost	27,457	11,999
Gross Unrealized Gains	323	266
Gross Unrealized Losses	(296)	(4)
Fair Value	27,484	12,261
Gross Unrealized Loss [Abstract]
Securities Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	296	4
Securities Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	0	0
Securities Available-for-sale Continuous Unrealized Loss Position, Total	296	4
Gross Unrealized Loss, Fair Value [Abstract]
Less than Twelve Months, Fair Value	12,632	1,706
Twelve Months or Longer, Fair Value	0	0
Fair Value, Total	12,632	1,706
Continuous Unrealized Loss Position, Qualitative Disclosure [Abstract]
Cause	caused by increases in market interest rates
Number of positions	25	2
Mortgage Backed Securities [Member]
Amortized costs and fair values of securities available-for-sale [Abstract]
Amortized Cost	223,379	102,884
Gross Unrealized Gains	1,536	396
Gross Unrealized Losses	(37)	(52)
Fair Value	224,878	103,228
Gross Unrealized Loss [Abstract]
Securities Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	37	52
Securities Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	0	0
Securities Available-for-sale Continuous Unrealized Loss Position, Total	37	52
Gross Unrealized Loss, Fair Value [Abstract]
Less than Twelve Months, Fair Value	25,738	29,364
Twelve Months or Longer, Fair Value	0	0
Fair Value, Total	25,738	29,364
Continuous Unrealized Loss Position, Qualitative Disclosure [Abstract]
Cause	caused by increases in market interest rates
Number of positions	2	3
Money Market Investments [Member]
Amortized costs and fair values of securities available-for-sale [Abstract]
Amortized Cost	1,593	1,306
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	1,593	1,306
Obligations of US Government Agencies [Member]
Amortized costs and fair value of securities held-to-maturity [Abstract]
Amortized Cost	470	1,370
Gross Unrecognized Holding Gain	4	8
Gross Unrecognized Holding Loss	0	0
Fair Value	474	1,378
Obligations of States and Political Subdivisions [Member]
Amortized costs and fair value of securities held-to-maturity [Abstract]
Amortized Cost	145	145
Gross Unrecognized Holding Gain	2	3
Gross Unrecognized Holding Loss	0	0
Fair Value	$ 147	$ 148

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Amount of the excess of amortized cost basis over fair value of securities that have been in a loss position for less than twelve months for securities categorized neither as held-to-maturity nor trading securities.

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Amount of investments in debt securities categorized as held-to-maturity valued at amortized cost, excludes other than temporary impairment (OTTI).

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