Investment Securities (Schedule of Unrealized Losses Not Recognized in Income) (Details) (USD $)	6 Months Ended	12 Months Ended
Jun. 30, 2012	Dec. 31, 2011
Schedule of Investments [Line Items]
Investment Securities Available-for-Sale: Less than 12 months, fair value	$ 78,908,000
Investment Securities Available-for-Sale: Less than 12 months, unrealized losses	(864,000)
Investment Securities Available-for-Sale: 12 Months or Longer, fair value	48,781,000
Investment Securities Available-for-Sale: 12 months or longer, unrealized losses	(4,207,000)
Investment Securities Available-for-Sale: Total, fair value	127,689,000
Investment Securities Available-for-Sale: Total, unrealized losses	(5,071,000)
Investment Securities Held-to-Maturity: Less than 12 months, fair value	7,697,000	18,187,000
Investment Securities Held-to-Maturity: 12 months or less, unrealized losses	(31,000)	(103,000)
Investment Securities Held-to-Maturity: Total, fair value	7,697,000	18,187,000
Investment Securities Held-to-Maturity: Total, unrealized losses	(31,000)	(103,000)
Temporarily Impaired Securities, Total Fair Value	135,386	143,892,000
Temporarily Impaired Securities, Total Unrealized Losses	(5,102)	(10,249,000)
Temporarily Impaired Securities, Less than 12 Months, Fair Value	86,605	122,295,000
Temporarily Impaired Securities, Less than 12 Months, Aggregate Losses	(895)	(4,817,000)
Temporarily Impaired Securities, 12 months or longer, Fair Value	48,781	21,597,000
Temporarily Impaired Securities, 12 months or longer, Aggregate losses	(4,207)	(5,432,000)
Commercial mortgage-backed securities [Member]
Schedule of Investments [Line Items]
Investment Securities Available-for-Sale: Less than 12 months, fair value	3,080,000
Investment Securities Available-for-Sale: Less than 12 months, unrealized losses	(17,000)
Investment Securities Available-for-Sale: Total, fair value	3,080,000
Investment Securities Available-for-Sale: Total, unrealized losses	(17,000)
Investment Securities Held-to-Maturity: Less than 12 months, fair value	1,538,000
Investment Securities Held-to-Maturity: 12 months or less, unrealized losses	(8,000)
Investment Securities Held-to-Maturity: Total, fair value	1,538,000
Investment Securities Held-to-Maturity: Total, unrealized losses	(8,000)
Residential mortgage-backed securities [Member]
Schedule of Investments [Line Items]
Investment Securities Available-for-Sale: Less than 12 months, fair value		2,013,000
Investment Securities Available-for-Sale: Less than 12 months, unrealized losses		(6,000)
Investment Securities Available-for-Sale: Total, fair value		2,013,000
Investment Securities Available-for-Sale: Total, unrealized losses		(6,000)
Obligations of U.S. states and political subdivisions [Member]
Schedule of Investments [Line Items]
Investment Securities Available-for-Sale: Less than 12 months, fair value	13,166,000	4,352,000
Investment Securities Available-for-Sale: Less than 12 months, unrealized losses	(203,000)	(36,000)
Investment Securities Available-for-Sale: Total, fair value	13,166,000	4,352,000
Investment Securities Available-for-Sale: Total, unrealized losses	(203,000)	(36,000)
Investment Securities Held-to-Maturity: Less than 12 months, fair value	1,021,000
Investment Securities Held-to-Maturity: 12 months or less, unrealized losses	(1,000)
Investment Securities Held-to-Maturity: Total, fair value	1,021,000
Investment Securities Held-to-Maturity: Total, unrealized losses	(1,000)
Trust preferred securities [Member]
Schedule of Investments [Line Items]
Investment Securities Available-for-Sale: Less than 12 months, fair value		4,325,000
Investment Securities Available-for-Sale: Less than 12 months, unrealized losses		(996,000)
Investment Securities Available-for-Sale: 12 Months or Longer, fair value	14,059,000	10,947,000
Investment Securities Available-for-Sale: 12 months or longer, unrealized losses	(1,827,000)	(3,398,000)
Investment Securities Available-for-Sale: Total, fair value	14,059,000	15,272,000
Investment Securities Available-for-Sale: Total, unrealized losses	(1,827,000)	(4,394,000)
Corporate bonds and notes [Member]
Schedule of Investments [Line Items]
Investment Securities Available-for-Sale: Less than 12 months, fair value	54,310,000	89,534,000
Investment Securities Available-for-Sale: Less than 12 months, unrealized losses	(517,000)	(3,663,000)
Investment Securities Available-for-Sale: 12 Months or Longer, fair value	31,643,000	7,509,000
Investment Securities Available-for-Sale: 12 months or longer, unrealized losses	(1,070,000)	(414,000)
Investment Securities Available-for-Sale: Total, fair value	85,953,000	97,043,000
Investment Securities Available-for-Sale: Total, unrealized losses	(1,587,000)	(4,077,000)
Collateralized mortgage obligations [Member]
Schedule of Investments [Line Items]
Investment Securities Available-for-Sale: 12 Months or Longer, fair value	1,752,000	1,899,000
Investment Securities Available-for-Sale: 12 months or longer, unrealized losses	(1,102,000)	(1,327,000)
Investment Securities Available-for-Sale: Total, fair value	1,752,000	1,899,000
Investment Securities Available-for-Sale: Total, unrealized losses	(1,102,000)	(1,327,000)
Investment Securities Held-to-Maturity: Less than 12 months, fair value		6,207,000
Investment Securities Held-to-Maturity: 12 months or less, unrealized losses		(69,000)
Investment Securities Held-to-Maturity: Total, fair value		6,207,000
Investment Securities Held-to-Maturity: Total, unrealized losses		(69,000)
Asset-backed securities [Member]
Schedule of Investments [Line Items]
Investment Securities Available-for-Sale: Less than 12 months, fair value	8,352,000	3,884,000
Investment Securities Available-for-Sale: Less than 12 months, unrealized losses	(127,000)	(13,000)
Investment Securities Available-for-Sale: Total, fair value	8,352,000	3,884,000
Investment Securities Available-for-Sale: Total, unrealized losses	(127,000)	(13,000)
Equity securities [Member]
Schedule of Investments [Line Items]
Investment Securities Available-for-Sale: 12 Months or Longer, fair value	349,000	262,000
Investment Securities Available-for-Sale: 12 months or longer, unrealized losses	(187,000)	(273,000)
Investment Securities Available-for-Sale: Total, fair value	349,000	262,000
Investment Securities Available-for-Sale: Total, unrealized losses	(187,000)	(273,000)
Other securities [Member]
Schedule of Investments [Line Items]
Investment Securities Available-for-Sale: 12 Months or Longer, fair value	978,000	980,000
Investment Securities Available-for-Sale: 12 months or longer, unrealized losses	(21,000)	(20,000)
Investment Securities Available-for-Sale: Total, fair value	978,000	980,000
Investment Securities Available-for-Sale: Total, unrealized losses	(21,000)	(20,000)
Federal agency obligations [Member]
Schedule of Investments [Line Items]
Investment Securities Held-to-Maturity: Less than 12 months, fair value	5,138,000	11,980,000
Investment Securities Held-to-Maturity: 12 months or less, unrealized losses	(22,000)	(34,000)
Investment Securities Held-to-Maturity: Total, fair value	5,138,000	11,980,000
Investment Securities Held-to-Maturity: Total, unrealized losses	$ (22,000)	$ (34,000)

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