Investment Securities (Unrealized Gain/Loss Positions) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Available-for-sale Securities [Abstract]
Amortized cost	$ 354,924	$ 438,057
Gross unrealized gains	1,282	3,048
Gross unrealized losses	6,166	26,491
Estimated fair value	350,040us-gaap_AvailableForSaleSecurities	414,614us-gaap_AvailableForSaleSecurities
Held-to-maturity Securities [Abstract]
Amortized cost	142,461	151,795
Gross unrealized gains	116	0
Gross unrealized losses	1,702	10,670
Estimated fair value	140,875	141,125
Amortized cost, Total	497,385	589,852
Gross unrealized gains, Total	1,398	3,048
Gross unrealized losses, Total	7,868	37,161
Estimated fair value, Total	490,915	555,739
Obligations of U.S. government sponsored enterprises [Member]
Available-for-sale Securities [Abstract]
Amortized cost	2,028	2,051
Gross unrealized gains	16	26
Gross unrealized losses	0	0
Estimated fair value	2,044	2,077
Business development company investment [Member]
Available-for-sale Securities [Abstract]
Amortized cost		1,753
Gross unrealized gains		984
Gross unrealized losses		0
Estimated fair value		2,737
Residential mortgage-backed securities - GSE [Member]
Available-for-sale Securities [Abstract]
Amortized cost	295,300	364,513
Gross unrealized gains	438	974
Gross unrealized losses	5,593	24,340
Estimated fair value	290,145	341,147
Held-to-maturity Securities [Abstract]
Amortized cost	132,396	141,724
Gross unrealized gains	116	0
Gross unrealized losses	1,635	9,907
Estimated fair value	130,877	131,817
Residential mortgage-backed securities - Private [Member]
Available-for-sale Securities [Abstract]
Amortized cost	16,455	19,770
Gross unrealized gains	820	982
Gross unrealized losses	4	0
Estimated fair value	17,271	20,752
Commercial mortgage-backed securities - GSE [Member]
Available-for-sale Securities [Abstract]
Amortized cost	22,377	22,767
Gross unrealized gains	0	0
Gross unrealized losses	419	1,328
Estimated fair value	21,958	21,439
Commercial mortgage-backed securities - Private [Member]
Available-for-sale Securities [Abstract]
Amortized cost	10,365	10,408
Gross unrealized gains	0	0
Gross unrealized losses	150	823
Estimated fair value	10,215	9,585
Held-to-maturity Securities [Abstract]
Amortized cost	10,065	10,071
Gross unrealized gains	0	0
Gross unrealized losses	67	763
Estimated fair value	9,998	9,308
Corporate notes [Member]
Available-for-sale Securities [Abstract]
Amortized cost	8,399	16,795
Gross unrealized gains	8	82
Gross unrealized losses	0	0
Estimated fair value	$ 8,407	$ 16,877

Available-for-sale and Held-to-maturity Securities, Amortized Cost Basis

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Available-for-sale and Held-to-maturity Securities, Gross Unrealized Gains

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Available-for-sale and Held-to-maturity Securities, Gross Unrealized Losses

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Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax

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Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax

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Held-to-maturity Securities, Unrecognized Holding Gain

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

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This item represents the cost of debt and equity 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 debt and equity financial instruments classified as either held-to-maturity or available-for-sale.

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Amount before other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity.

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Fair value of investments in debt securities classified as held-to-maturity.

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