Investment Securities Available for Sale (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2012
Schedule of Available-for-sale Securities [Line Items]
Available-For-Sale Securities, at Amortized Cost	$ 481,778	$ 469,384	$ 413,596
Available-for-Sale	486,888	478,698	425,416
Gross Unrealized Gains	6,280	9,843	12,226
Gross Unrealized Losses	1,170	529	406
Available-For-Sale Securities, Pledged as Collateral	314,693	260,292	277,357
Maturities of Debt Securities, at Amortized Cost
Within One Year	74,382
From 1 - 5 Years	393,360
From 5 - 10 Years	11,236
Over 10 Years	1,680
Maturities of Debt Securities at Fair Value
Within One Year	74,980
From 1 - 5 Years	397,400
From 5 - 10 Years	11,846
Over 10 Years	1,480
Securities in a Continuous Loss Position, at Fair Value
Less than 12 Months	188,707	137,839	42,056
12 Months or Longer	9,305	7,117	0
Total	198,012	144,956	42,056
Number of Securities in a Continuous Loss Position, in number of securities	286	238	82
Unrealized Losses on Securities in a Continuous Loss Position
Less than 12 Months	952	492	406
12 Months or Longer	218	37	0
Total	1,170	529	406
Agency Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-For-Sale Securities, at Amortized Cost	32,500		40,600
Available-for-Sale	33,600		42,100
US Government-sponsored Enterprises Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-For-Sale Securities, at Amortized Cost	146,700		262,000
Available-for-Sale	151,600		252,100
U.S. Agency Obligations [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-For-Sale Securities, at Amortized Cost	150,184	122,297	56,054
Available-for-Sale	149,774	122,457	56,391
Gross Unrealized Gains	2	204	337
Gross Unrealized Losses	412	44	0
Maturities of Debt Securities, at Amortized Cost
Within One Year	0
From 1 - 5 Years	150,184
From 5 - 10 Years	0
Over 10 Years	0
Maturities of Debt Securities at Fair Value
Within One Year	0
From 1 - 5 Years	149,774
From 5 - 10 Years	0
Over 10 Years	0
Securities in a Continuous Loss Position, at Fair Value
Less than 12 Months	105,517	72,531	4,999
12 Months or Longer	4,992	0	0
Total	110,509	72,531	4,999
Number of Securities in a Continuous Loss Position, in number of securities	30	22	1
Unrealized Losses on Securities in a Continuous Loss Position
Less than 12 Months	405	44	0
12 Months or Longer	7	0	0
Total	412	44	0
State and Municipal Obligations [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-For-Sale Securities, at Amortized Cost	134,059	84,798	62,706
Available-for-Sale	133,919	84,838	62,965
Gross Unrealized Gains	175	206	285
Gross Unrealized Losses	315	166	26
Maturities of Debt Securities, at Amortized Cost
Within One Year	53,557
From 1 - 5 Years	77,849
From 5 - 10 Years	1,973
Over 10 Years	680
Maturities of Debt Securities at Fair Value
Within One Year	53,590
From 1 - 5 Years	77,644
From 5 - 10 Years	2,005
Over 10 Years	680
Securities in a Continuous Loss Position, at Fair Value
Less than 12 Months	58,710	46,627	17,432
12 Months or Longer	3,513	2,149	0
Total	62,223	48,776	17,432
Number of Securities in a Continuous Loss Position, in number of securities	230	198	73
Unrealized Losses on Securities in a Continuous Loss Position
Less than 12 Months	304	160	26
12 Months or Longer	11	6	0
Total	315	166	26
Mortgage-Backed Securities - Residential [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-For-Sale Securities, at Amortized Cost	179,235	252,480	292,716
Available-for-Sale	185,215	261,804	304,085
Gross Unrealized Gains	6,041	9,405	11,549
Gross Unrealized Losses	61	81	180
Maturities of Debt Securities, at Amortized Cost
Within One Year	20,825
From 1 - 5 Years	149,147
From 5 - 10 Years	9,263
Over 10 Years	0
Maturities of Debt Securities at Fair Value
Within One Year	21,390
From 1 - 5 Years	153,984
From 5 - 10 Years	9,841
Over 10 Years	0
Securities in a Continuous Loss Position, at Fair Value
Less than 12 Months	8,482	10,230	18,825
12 Months or Longer	0	4,968	0
Total	8,482	15,198	18,825
Number of Securities in a Continuous Loss Position, in number of securities	4	7	7
Unrealized Losses on Securities in a Continuous Loss Position
Less than 12 Months	61	50	180
12 Months or Longer	0	31	0
Total	61	81	180
Corporate and Other Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-For-Sale Securities, at Amortized Cost	17,180	8,689	1,000
Available-for-Sale	16,798	8,451	800
Gross Unrealized Gains	0	0	0
Gross Unrealized Losses	382	238	200
Maturities of Debt Securities, at Amortized Cost
Within One Year	0
From 1 - 5 Years	16,180
From 5 - 10 Years	0
Over 10 Years	1,000
Maturities of Debt Securities at Fair Value
Within One Year	0
From 1 - 5 Years	15,998
From 5 - 10 Years	0
Over 10 Years	800
Securities in a Continuous Loss Position, at Fair Value
Less than 12 Months	15,998	8,451	800
12 Months or Longer	800	0	0
Total	16,798	8,451	800
Number of Securities in a Continuous Loss Position, in number of securities	22	11	1
Unrealized Losses on Securities in a Continuous Loss Position
Less than 12 Months	182	238	200
12 Months or Longer	200	0	0
Total	382	238	200
Mutual Funds and Equity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-For-Sale Securities, at Amortized Cost	1,120	1,120	1,120
Available-for-Sale	1,182	1,148	1,175
Gross Unrealized Gains	62	28	55
Gross Unrealized Losses	0	0	0
Securities in a Continuous Loss Position, at Fair Value
Less than 12 Months	0	0	0
12 Months or Longer	0	0	0
Total	0	0	0
Number of Securities in a Continuous Loss Position, in number of securities	0	0	0
Unrealized Losses on Securities in a Continuous Loss Position
Less than 12 Months	0	0	0
12 Months or Longer	0	0	0
Total	$ 0	$ 0	$ 0