Securities - (Details 1) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Amortized cost and fair value of securities available for sale
Amortized Cost	$ 541,734	$ 553,770
Gross Unrealized Gains	12,083	10,280
Gross Unrealized Losses	(8,020)	(10,466)
Securities available for sale	545,797us-gaap_AvailableForSaleSecurities	553,584us-gaap_AvailableForSaleSecurities
Trust preferred securities
Amortized cost and fair value of securities available for sale
Amortized Cost	26,057	26,400
Gross Unrealized Gains	79	137
Gross Unrealized Losses	(6,010)	(6,781)
Securities available for sale	20,126	19,756
Other debt securities
Amortized cost and fair value of securities available for sale
Amortized Cost	16,999	17,517
Gross Unrealized Gains	537	487
Gross Unrealized Losses	(42)	(74)
Securities available for sale	17,494	17,930
Other equity securities
Amortized cost and fair value of securities available for sale
Amortized Cost	2,331	2,331
Gross Unrealized Gains	1,329	1,268
Gross Unrealized Losses	0	0
Securities available for sale	3,660	3,599
Obligations of other U.S. Government agencies and corporations
Amortized cost and fair value of securities available for sale
Amortized Cost	6,113	6,119
Gross Unrealized Gains	170	147
Gross Unrealized Losses	(52)	(119)
Securities available for sale	6,231	6,147
Government agency mortgage backed securities \| Residential mortgage backed securities:
Amortized cost and fair value of securities available for sale
Amortized Cost	292,587	292,283
Gross Unrealized Gains	5,981	4,908
Gross Unrealized Losses	(486)	(832)
Securities available for sale	298,082	296,359
Government agency mortgage backed securities \| Commercial mortgage backed securities:
Amortized cost and fair value of securities available for sale
Amortized Cost	42,019	45,714
Gross Unrealized Gains	1,583	1,608
Gross Unrealized Losses	(32)	(137)
Securities available for sale	43,570	47,185
Government agency collateralized mortgage obligations \| Residential mortgage backed securities:
Amortized cost and fair value of securities available for sale
Amortized Cost	151,075	158,436
Gross Unrealized Gains	2,131	1,523
Gross Unrealized Losses	(1,398)	(2,523)
Securities available for sale	151,808	157,436
Government agency collateralized mortgage obligations \| Commercial mortgage backed securities:
Amortized cost and fair value of securities available for sale
Amortized Cost	4,553	4,970
Gross Unrealized Gains	273	202
Gross Unrealized Losses	0	0
Securities available for sale	$ 4,826	$ 5,172

This item represents the cost of debt securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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