Securities (Details 4) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
	Mar. 31, 2014 position	Dec. 31, 2013 position
Held-to-maturity Securities [Abstract]
Securities in Unrealized Loss Positions (positions)	104	141
Fair Value, Held to Maturity, Less than 12 Months	$ 172,187	$ 165,250
Unrealized Losses, Held to Maturity, Less than 12 months	(7,258)	(10,404)
Fair Value, Held to Maturity, 12 Months or More	13,366	10,023
Unrealized Losses, Held to Maturity, 12 Months or More	(976)	(1,006)
Fair Value, Held to Maturity, Total	185,553	175,273
Unrealized Losses, Held to Maturity, Total	(8,234)	(11,410)
Available-for-sale Securities [Abstract]
Securities in Unrealized Loss Positions (positions)	72	68
Fair Value, Available for Sale, Less than 12 Months	238,934	230,823
Unrealized Losses, Available for Sale, Less than 12 months	(4,957)	(7,921)
Fair Value, Available for Sale, 12 Months or More	70,597	48,342
Unrealized Losses, Available for Sale, 12 months or More	(11,536)	(12,120)
Fair Value, Available for Sale, Total	309,531	279,165
Unrealized Losses, Available for Sale, Total	(16,493)	(20,041)
Trust preferred securities
Available-for-sale Securities [Abstract]
Securities in Unrealized Loss Positions (positions)	4	3
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	17,964	16,456
Unrealized Losses, Available for Sale, 12 months or More	(8,426)	(9,933)
Fair Value, Available for Sale, Total	17,964	16,456
Unrealized Losses, Available for Sale, Total	(8,426)	(9,933)
Other debt securities
Available-for-sale Securities [Abstract]
Securities in Unrealized Loss Positions (positions)	2	4
Fair Value, Available for Sale, Less than 12 Months	2,713	7,100
Unrealized Losses, Available for Sale, Less than 12 months	(170)	(217)
Fair Value, Available for Sale, 12 Months or More	1,817	1,897
Unrealized Losses, Available for Sale, 12 months or More	(7)	(13)
Fair Value, Available for Sale, Total	4,530	8,997
Unrealized Losses, Available for Sale, Total	(177)	(230)
Other equity securities
Available-for-sale Securities [Abstract]
Securities in Unrealized Loss Positions (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
Held-to-maturity Securities [Abstract]
Securities in Unrealized Loss Positions (positions)	28	28
Fair Value, Held to Maturity, Less than 12 Months	126,526	105,747
Unrealized Losses, Held to Maturity, Less than 12 months	(6,053)	(7,826)
Fair Value, Held to Maturity, 12 Months or More	9,279	9,090
Unrealized Losses, Held to Maturity, 12 Months or More	(711)	(901)
Fair Value, Held to Maturity, Total	135,805	114,837
Unrealized Losses, Held to Maturity, Total	(6,764)	(8,727)
Available-for-sale Securities [Abstract]
Securities in Unrealized Loss Positions (positions)	0	1
Fair Value, Available for Sale, Less than 12 Months	3,841	3,799
Unrealized Losses, Available for Sale, Less than 12 months	(159)	(201)
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	3,841	3,799
Unrealized Losses, Available for Sale, Total	(159)	(201)
Obligations of states and political subdivisions
Held-to-maturity Securities [Abstract]
Securities in Unrealized Loss Positions (positions)	76	113
Fair Value, Held to Maturity, Less than 12 Months	45,661	59,503
Unrealized Losses, Held to Maturity, Less than 12 months	(1,205)	(2,578)
Fair Value, Held to Maturity, 12 Months or More	4,087	933
Unrealized Losses, Held to Maturity, 12 Months or More	(265)	(105)
Fair Value, Held to Maturity, Total	49,748	60,436
Unrealized Losses, Held to Maturity, Total	(1,470)	(2,683)
Government agency mortgage backed securities | Residential mortgage backed securities:
Available-for-sale Securities [Abstract]
Securities in Unrealized Loss Positions (positions)	38	35
Fair Value, Available for Sale, Less than 12 Months	148,117	134,858
Unrealized Losses, Available for Sale, Less than 12 months	(2,197)	(3,451)
Fair Value, Available for Sale, 12 Months or More	18,501	13,239
Unrealized Losses, Available for Sale, 12 months or More	(1,100)	(963)
Fair Value, Available for Sale, Total	166,618	148,097
Unrealized Losses, Available for Sale, Total	(3,297)	(4,414)
Government agency mortgage backed securities | Commercial mortgage backed securities:
Available-for-sale Securities [Abstract]
Securities in Unrealized Loss Positions (positions)	3	4
Fair Value, Available for Sale, Less than 12 Months	10,487	16,570
Unrealized Losses, Available for Sale, Less than 12 months	(406)	(584)
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	10,487	16,570
Unrealized Losses, Available for Sale, Total	(406)	(584)
Government agency collateralized mortgage obligations | Residential mortgage backed securities:
Available-for-sale Securities [Abstract]
Securities in Unrealized Loss Positions (positions)	25	21
Fair Value, Available for Sale, Less than 12 Months	73,776	68,496
Unrealized Losses, Available for Sale, Less than 12 months	(2,025)	(3,468)
Fair Value, Available for Sale, 12 Months or More	32,315	16,750
Unrealized Losses, Available for Sale, 12 months or More	(2,003)	(1,211)
Fair Value, Available for Sale, Total	106,091	85,246
Unrealized Losses, Available for Sale, Total	(4,028)	(4,679)
Government agency collateralized mortgage obligations | Commercial mortgage backed securities:
Available-for-sale Securities [Abstract]
Securities in Unrealized Loss Positions (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
Less than 12 Months
Held-to-maturity Securities [Abstract]
Securities in Unrealized Loss Positions (positions)	96	137
Available-for-sale Securities [Abstract]
Securities in Unrealized Loss Positions (positions)	54	57
Less than 12 Months | Trust preferred securities
Available-for-sale Securities [Abstract]
Securities in Unrealized Loss Positions (positions)	0	0
Less than 12 Months | Other debt securities
Available-for-sale Securities [Abstract]
Securities in Unrealized Loss Positions (positions)	1	3
Less than 12 Months | Other equity securities
Available-for-sale Securities [Abstract]
Securities in Unrealized Loss Positions (positions)		0
Less than 12 Months | Obligations of other U.S. Government agencies and corporations
Held-to-maturity Securities [Abstract]
Securities in Unrealized Loss Positions (positions)	26	26
Available-for-sale Securities [Abstract]
Securities in Unrealized Loss Positions (positions)	0	1
Less than 12 Months | Obligations of states and political subdivisions
Held-to-maturity Securities [Abstract]
Securities in Unrealized Loss Positions (positions)	70	111
Less than 12 Months | Government agency mortgage backed securities | Residential mortgage backed securities:
Available-for-sale Securities [Abstract]
Securities in Unrealized Loss Positions (positions)	33	32
Less than 12 Months | Government agency mortgage backed securities | Commercial mortgage backed securities:
Available-for-sale Securities [Abstract]
Securities in Unrealized Loss Positions (positions)	3	4
Less than 12 Months | Government agency collateralized mortgage obligations | Residential mortgage backed securities:
Available-for-sale Securities [Abstract]
Securities in Unrealized Loss Positions (positions)	17	17
Less than 12 Months | Government agency collateralized mortgage obligations | Commercial mortgage backed securities:
Available-for-sale Securities [Abstract]
Securities in Unrealized Loss Positions (positions)	0	0
12 Months or More
Held-to-maturity Securities [Abstract]
Securities in Unrealized Loss Positions (positions)	8	4
Available-for-sale Securities [Abstract]
Securities in Unrealized Loss Positions (positions)	18	11
12 Months or More | Trust preferred securities
Available-for-sale Securities [Abstract]
Securities in Unrealized Loss Positions (positions)	4	3
12 Months or More | Other debt securities
Available-for-sale Securities [Abstract]
Securities in Unrealized Loss Positions (positions)	1	1
12 Months or More | Other equity securities
Available-for-sale Securities [Abstract]
Securities in Unrealized Loss Positions (positions)		0
12 Months or More | Obligations of other U.S. Government agencies and corporations
Held-to-maturity Securities [Abstract]
Securities in Unrealized Loss Positions (positions)	2	2
Available-for-sale Securities [Abstract]
Securities in Unrealized Loss Positions (positions)	0	0
12 Months or More | Obligations of states and political subdivisions
Held-to-maturity Securities [Abstract]
Securities in Unrealized Loss Positions (positions)	6	2
12 Months or More | Government agency mortgage backed securities | Residential mortgage backed securities:
Available-for-sale Securities [Abstract]
Securities in Unrealized Loss Positions (positions)	5	3
12 Months or More | Government agency mortgage backed securities | Commercial mortgage backed securities:
Available-for-sale Securities [Abstract]
Securities in Unrealized Loss Positions (positions)	0	0
12 Months or More | Government agency collateralized mortgage obligations | Residential mortgage backed securities:
Available-for-sale Securities [Abstract]
Securities in Unrealized Loss Positions (positions)	8	4
12 Months or More | Government agency collateralized mortgage obligations | Commercial mortgage backed securities:
Available-for-sale Securities [Abstract]
Securities in Unrealized Loss Positions (positions)	0	0