Securities (Details 3) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Amortized cost and fair value of securities by contractual maturity
Amortized Cost, Held to Maturity, Due within one year	$ 9,835
Amortized Cost, Held to Maturity, Due after one year through five years	37,045
Amortized Cost, Held to Maturity, Due after five years through ten years	110,135
Amortized Cost, Held to Maturity, Due after ten years	142,124
Fair Value, Held to Maturity, Due within one year	9,905
Fair Value, Held to Maturity, Due after one year through five years	38,207
Fair Value, Held to Maturity, Due after five years through ten years	113,946
Fair Value, Held to Maturity, Due after ten years	154,640
Amortized Cost, Available for Sale, Due after five years through ten years	2,175
Amortized Cost, Available for Sale, Due after ten years	29,459
Fair Value, Available for Sale, Due after five years through ten years	2,447
Fair Value, Available for Sale, Due after ten years	15,342
Amortized Cost, Held to Maturity	299,139	332,410
Fair Value, Held to Maturity	316,698	344,618
Amortized Cost, Available for Sale	380,653
Fair Value	381,540	463,931
Other debt securities [Member]
Amortized cost and fair value of securities by contractual maturity
Amortized Cost, Held to Maturity
Fair Value, Held to Maturity
Amortized Cost, Available for Sale	22,871
Fair Value	23,664	21,875
Other equity securities [Member]
Amortized cost and fair value of securities by contractual maturity
Amortized Cost, Held to Maturity
Fair Value, Held to Maturity
Amortized Cost, Available for Sale	2,355
Fair Value	3,033	2,237
Government agency mortgage backed securities [Member] \| Residential mortgage backed securities [Member]
Amortized cost and fair value of securities by contractual maturity
Amortized Cost, Held to Maturity
Fair Value, Held to Maturity
Amortized Cost, Available for Sale	166,807
Fair Value	174,582	230,667
Government agency mortgage backed securities [Member] \| Commercial mortgage backed securities [Member]
Amortized cost and fair value of securities by contractual maturity
Amortized Cost, Held to Maturity
Fair Value, Held to Maturity
Amortized Cost, Available for Sale	37,064
Fair Value	40,095	36,669
Government agency collateralized mortgage obligations [Member] \| Residential mortgage backed securities [Member]
Amortized cost and fair value of securities by contractual maturity
Amortized Cost, Held to Maturity
Fair Value, Held to Maturity
Amortized Cost, Available for Sale	114,811
Fair Value	116,926	136,987
Government agency collateralized mortgage obligations [Member] \| Commercial mortgage backed securities [Member]
Amortized cost and fair value of securities by contractual maturity
Amortized Cost, Held to Maturity
Fair Value, Held to Maturity
Amortized Cost, Available for Sale	5,111
Fair Value	$ 5,451	$ 5,316

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Amortized cost held to maturity due after five year through ten years.

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Amount of available-for-sale debt securities at cost, net of adjustments, maturing in the sixth fiscal year through the tenth fiscal year following the latest fiscal year. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings (less any cumulative-effect adjustments, as defined) and fair value hedge accounting adjustments.

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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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