Securities (Details 4) (USD $) In Thousands, unless otherwise specified	9 Months Ended	12 Months Ended
	Sep. 30, 2013	Dec. 31, 2012
Cash and Cash Equivalents [Line Items]
Held-to-maturity, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions	140	13
Held-to-maturity Securities [Abstract]
Fair Value, Held to Maturity, Less than 12 Months	$ 198,245	$ 38,085
Unrealized Losses, Held to Maturity, Less than 12 months	(10,406)	(266)
Fair Value, Held to Maturity, 12 Months or More	0	126
Unrealized Losses, Held to Maturity, 12 Months or More	0	(1)
Fair Value, Held to Maturity, Total	198,245	38,211
Unrealized Losses, Held to Maturity, Total	(10,406)	(267)
Available-for-sale Securities [Abstract]
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions	55	20
Fair Value, Available for Sale, Less than 12 Months	195,004	60,047
Unrealized Losses, Available for Sale, Less than 12 months	(8,050)	(480)
Fair Value, Available for Sale, 12 Months or More	26,059	18,861
Unrealized Losses, Available for Sale, 12 months or More	(11,184)	(13,555)
Fair Value, Available for Sale, Total	221,063	78,908
Unrealized Losses, Available for Sale, Total	(19,234)	(14,035)
Trust preferred securities [Member]
Available-for-sale Securities [Abstract]
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions	4	4
Fair Value, Available for Sale, Less than 12 Months	0	0
Unrealized Losses, Available for Sale, Less than 12 months	0	0
Fair Value, Available for Sale, 12 Months or More	16,753	15,068
Unrealized Losses, Available for Sale, 12 months or More	(10,876)	(13,544)
Fair Value, Available for Sale, Total	16,753	15,068
Unrealized Losses, Available for Sale, Total	(10,876)	(13,544)
Other debt securities [Member]
Available-for-sale Securities [Abstract]
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions	2	1
Fair Value, Available for Sale, Less than 12 Months	2,764	0
Unrealized Losses, Available for Sale, Less than 12 months	(206)	0
Fair Value, Available for Sale, 12 Months or More	1,971	2,188
Unrealized Losses, Available for Sale, 12 months or More	(7)	(1)
Fair Value, Available for Sale, Total	4,735	2,188
Unrealized Losses, Available for Sale, Total	(213)	(1)
Equity Securities [Member]
Available-for-sale Securities [Abstract]
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions		0
Fair Value, Available for Sale, Less than 12 Months		0
Unrealized Losses, Available for Sale, Less than 12 months		0
Fair Value, Available for Sale, 12 Months or More		0
Unrealized Losses, Available for Sale, 12 months or More		0
Fair Value, Available for Sale, Total		0
Unrealized Losses, Available for Sale, Total		0
Obligations of other U.S. Government agencies and corporations [Member]
Cash and Cash Equivalents [Line Items]
Held-to-maturity, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions	30	8
Held-to-maturity Securities [Abstract]
Fair Value, Held to Maturity, Less than 12 Months	138,850	35,224
Unrealized Losses, Held to Maturity, Less than 12 months	(7,707)	(232)
Fair Value, Held to Maturity, 12 Months or More	0	0
Unrealized Losses, Held to Maturity, 12 Months or More	0	0
Fair Value, Held to Maturity, Total	138,850	35,224
Unrealized Losses, Held to Maturity, Total	(7,707)	(232)
Available-for-sale Securities [Abstract]
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions	1	0
Fair Value, Available for Sale, Less than 12 Months	3,789	0
Unrealized Losses, Available for Sale, Less than 12 months	(211)	0
Fair Value, Available for Sale, 12 Months or More	0	0
Unrealized Losses, Available for Sale, 12 months or More	0	0
Fair Value, Available for Sale, Total	3,789	0
Unrealized Losses, Available for Sale, Total	(211)	0
Obligations of states and political subdivisions [Member]
Cash and Cash Equivalents [Line Items]
Held-to-maturity, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions	110	5
Held-to-maturity Securities [Abstract]
Fair Value, Held to Maturity, Less than 12 Months	59,395	2,861
Unrealized Losses, Held to Maturity, Less than 12 months	(2,699)	(34)
Fair Value, Held to Maturity, 12 Months or More	0	126
Unrealized Losses, Held to Maturity, 12 Months or More	0	(1)
Fair Value, Held to Maturity, Total	59,395	2,987
Unrealized Losses, Held to Maturity, Total	(2,699)	(35)
Government agency mortgage backed securities [Member] | Residential mortgage backed securities [Member]
Available-for-sale Securities [Abstract]
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions	24	3
Fair Value, Available for Sale, Less than 12 Months	95,531	15,431
Unrealized Losses, Available for Sale, Less than 12 months	(3,610)	(91)
Fair Value, Available for Sale, 12 Months or More	0	0
Unrealized Losses, Available for Sale, 12 months or More	0	0
Fair Value, Available for Sale, Total	95,531	15,431
Unrealized Losses, Available for Sale, Total	(3,610)	(91)
Government agency mortgage backed securities [Member] | Commercial mortgage backed securities [Member]
Available-for-sale Securities [Abstract]
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions	4	0
Fair Value, Available for Sale, Less than 12 Months	16,672	0
Unrealized Losses, Available for Sale, Less than 12 months	(547)	0
Fair Value, Available for Sale, 12 Months or More	0	0
Unrealized Losses, Available for Sale, 12 months or More	0	0
Fair Value, Available for Sale, Total	16,672	0
Unrealized Losses, Available for Sale, Total	(547)	0
Government agency collateralized mortgage obligations [Member] | Residential mortgage backed securities [Member]
Available-for-sale Securities [Abstract]
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions	20	12
Fair Value, Available for Sale, Less than 12 Months	76,248	44,616
Unrealized Losses, Available for Sale, Less than 12 months	(3,476)	(389)
Fair Value, Available for Sale, 12 Months or More	7,335	1,605
Unrealized Losses, Available for Sale, 12 months or More	(301)	(10)
Fair Value, Available for Sale, Total	83,583	46,221
Unrealized Losses, Available for Sale, Total	(3,777)	(399)
Government agency collateralized mortgage obligations [Member] | Commercial mortgage backed securities [Member]
Available-for-sale Securities [Abstract]
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions	0	0
Fair Value, Available for Sale, Less than 12 Months	0	0
Unrealized Losses, Available for Sale, Less than 12 months	0	0
Fair Value, Available for Sale, 12 Months or More	0	0
Unrealized Losses, Available for Sale, 12 months or More	0	0
Fair Value, Available for Sale, Total	0	0
Unrealized Losses, Available for Sale, Total	$ 0	$ 0
LessThan12Months [Member]
Cash and Cash Equivalents [Line Items]
Held-to-maturity, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions	140	12
Available-for-sale Securities [Abstract]
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions	48	14
LessThan12Months [Member] | Trust preferred securities [Member]
Available-for-sale Securities [Abstract]
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions	0	0
LessThan12Months [Member] | Other debt securities [Member]
Available-for-sale Securities [Abstract]
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions	1	0
LessThan12Months [Member] | Equity Securities [Member]
Available-for-sale Securities [Abstract]
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions		0
LessThan12Months [Member] | Obligations of other U.S. Government agencies and corporations [Member]
Cash and Cash Equivalents [Line Items]
Held-to-maturity, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions	30	8
Available-for-sale Securities [Abstract]
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions	1	0
LessThan12Months [Member] | Obligations of states and political subdivisions [Member]
Cash and Cash Equivalents [Line Items]
Held-to-maturity, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions	110	4
LessThan12Months [Member] | Government agency mortgage backed securities [Member] | Residential mortgage backed securities [Member]
Available-for-sale Securities [Abstract]
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions	24	3
LessThan12Months [Member] | Government agency mortgage backed securities [Member] | Commercial mortgage backed securities [Member]
Available-for-sale Securities [Abstract]
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions	4	0
LessThan12Months [Member] | Government agency collateralized mortgage obligations [Member] | Residential mortgage backed securities [Member]
Available-for-sale Securities [Abstract]
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions	18	11
LessThan12Months [Member] | Government agency collateralized mortgage obligations [Member] | Commercial mortgage backed securities [Member]
Available-for-sale Securities [Abstract]
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions	0	0
GreaterThan12Months [Member]
Cash and Cash Equivalents [Line Items]
Held-to-maturity, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions	0	1
Available-for-sale Securities [Abstract]
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions	7	6
GreaterThan12Months [Member] | Trust preferred securities [Member]
Available-for-sale Securities [Abstract]
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions	4	4
GreaterThan12Months [Member] | Other debt securities [Member]
Available-for-sale Securities [Abstract]
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions	1	1
GreaterThan12Months [Member] | Equity Securities [Member]
Available-for-sale Securities [Abstract]
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions		0
GreaterThan12Months [Member] | Obligations of other U.S. Government agencies and corporations [Member]
Cash and Cash Equivalents [Line Items]
Held-to-maturity, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions	0	0
Available-for-sale Securities [Abstract]
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions	0	0
GreaterThan12Months [Member] | Obligations of states and political subdivisions [Member]
Cash and Cash Equivalents [Line Items]
Held-to-maturity, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions	0	1
GreaterThan12Months [Member] | Government agency mortgage backed securities [Member] | Residential mortgage backed securities [Member]
Available-for-sale Securities [Abstract]
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions	0	0
GreaterThan12Months [Member] | Government agency mortgage backed securities [Member] | Commercial mortgage backed securities [Member]
Available-for-sale Securities [Abstract]
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions	0	0
GreaterThan12Months [Member] | Government agency collateralized mortgage obligations [Member] | Residential mortgage backed securities [Member]
Available-for-sale Securities [Abstract]
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions	2	1
GreaterThan12Months [Member] | Government agency collateralized mortgage obligations [Member] | Commercial mortgage backed securities [Member]
Available-for-sale Securities [Abstract]
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions	0	0