Securities (Details 1) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Amortized cost and fair value of securities available for sale
Amortized Cost, Available for Sale	$ 380,653	$ 468,711
Gross Unrealized Gains, Available for Sale	15,485	13,084
Gross Unrealized Losses, Available for Sale	(14,598)	(17,864)
Fair Value, Available for Sale	381,540	463,931
Trust preferred securities [Member]
Amortized cost and fair value of securities available for sale
Amortized Cost, Available for Sale	29,459	30,410
Gross Unrealized Gains, Available for Sale
Gross Unrealized Losses, Available for Sale	(14,117)	(17,625)
Fair Value, Available for Sale	15,342	12,785
Other debt securities [Member]
Amortized cost and fair value of securities available for sale
Amortized Cost, Available for Sale	22,871	21,351
Gross Unrealized Gains, Available for Sale	841	527
Gross Unrealized Losses, Available for Sale	(48)	(3)
Fair Value, Available for Sale	23,664	21,875
Other equity securities [Member]
Amortized cost and fair value of securities available for sale
Amortized Cost, Available for Sale	2,355	2,341
Gross Unrealized Gains, Available for Sale	678
Gross Unrealized Losses, Available for Sale		(104)
Fair Value, Available for Sale	3,033	2,237
Obligations of other U.S. Government agencies and corporations [Member]
Amortized cost and fair value of securities available for sale
Amortized Cost, Available for Sale	2,175	17,193
Gross Unrealized Gains, Available for Sale	272	202
Gross Unrealized Losses, Available for Sale
Fair Value, Available for Sale	2,447	17,395
Government agency mortgage backed securities [Member] | Residential mortgage backed securities [Member]
Amortized cost and fair value of securities available for sale
Amortized Cost, Available for Sale	166,807	224,242
Gross Unrealized Gains, Available for Sale	7,777	6,455
Gross Unrealized Losses, Available for Sale	(2)	(30)
Fair Value, Available for Sale	174,582	230,667
Government agency mortgage backed securities [Member] | Commercial mortgage backed securities [Member]
Amortized cost and fair value of securities available for sale
Amortized Cost, Available for Sale	37,064	34,635
Gross Unrealized Gains, Available for Sale	3,062	2,054
Gross Unrealized Losses, Available for Sale	(31)	(20)
Fair Value, Available for Sale	40,095	36,669
Government agency collateralized mortgage obligations [Member] | Residential mortgage backed securities [Member]
Amortized cost and fair value of securities available for sale
Amortized Cost, Available for Sale	114,811	133,369
Gross Unrealized Gains, Available for Sale	2,515	3,700
Gross Unrealized Losses, Available for Sale	(400)	(82)
Fair Value, Available for Sale	116,926	136,987
Government agency collateralized mortgage obligations [Member] | Commercial mortgage backed securities [Member]
Amortized cost and fair value of securities available for sale
Amortized Cost, Available for Sale	5,111	5,170
Gross Unrealized Gains, Available for Sale	340	146
Gross Unrealized Losses, Available for Sale
Fair Value, Available for Sale	$ 5,451	$ 5,316