Investment Securities (Unrealized Gain/Loss Positions) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Available-for-sale Securities [Abstract]
Amortized Cost	$ 398,815	$ 354,924
Gross Unrealized Gains	920	1,282
Gross Unrealized Losses	9,301	6,166
Estimated Fair Value	390,434	350,040
Held-to-maturity Securities [Abstract]
Amortized Cost	147,967	142,461
Gross Unrealized Gains	0	116
Gross Unrealized Losses	2,782	1,702
Estimated Fair Value	145,185	140,875
Amortized Cost, Total	546,782	497,385
Gross Unrealized Gains, Total	920	1,398
Gross Unrealized Losses, Total	12,083	7,868
Estimated Fair Value, Total	535,619	490,915
Obligations of U.S. government sponsored enterprises [Member]
Available-for-sale Securities [Abstract]
Amortized Cost	2,005	2,028
Gross Unrealized Gains	3	16
Gross Unrealized Losses	0	0
Estimated Fair Value	2,008	2,044
Residential mortgage-backed securities - GSE [Member]
Available-for-sale Securities [Abstract]
Amortized Cost	286,057	295,300
Gross Unrealized Gains	339	438
Gross Unrealized Losses	8,289	5,593
Estimated Fair Value	278,107	290,145
Held-to-maturity Securities [Abstract]
Amortized Cost	120,197	132,396
Gross Unrealized Gains	0	116
Gross Unrealized Losses	2,310	1,635
Estimated Fair Value	117,887	130,877
Residential mortgage-backed securities - Private [Member]
Available-for-sale Securities [Abstract]
Amortized Cost	33,235	16,455
Gross Unrealized Gains	578	820
Gross Unrealized Losses	236	4
Estimated Fair Value	33,577	17,271
Held-to-maturity Securities [Abstract]
Amortized Cost	17,712
Gross Unrealized Gains	0
Gross Unrealized Losses	298
Estimated Fair Value	17,414
Commercial mortgage-backed securities - GSE [Member]
Available-for-sale Securities [Abstract]
Amortized Cost	21,980	22,377
Gross Unrealized Gains	0	0
Gross Unrealized Losses	368	419
Estimated Fair Value	21,612	21,958
Commercial mortgage-backed securities - Private [Member]
Available-for-sale Securities [Abstract]
Amortized Cost	17,869	10,365
Gross Unrealized Gains	0	0
Gross Unrealized Losses	294	150
Estimated Fair Value	17,575	10,215
Held-to-maturity Securities [Abstract]
Amortized Cost	10,058	10,065
Gross Unrealized Gains	0	0
Gross Unrealized Losses	174	67
Estimated Fair Value	9,884	9,998
Corporate notes [Member]
Available-for-sale Securities [Abstract]
Amortized Cost	37,669	8,399
Gross Unrealized Gains	0	8
Gross Unrealized Losses	114	0
Estimated Fair Value	$ 37,555	$ 8,407

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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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 gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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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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Amount of debt and equity financial instruments classified as either held-to-maturity or available-for-sale.

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