Investment Securities Available for Sale (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011	Sep. 30, 2011
Schedule of Available-for-sale Securities [Line Items]
Available-For-Sale Securities, at Amortized Cost	$ 413,596	$ 545,265	$ 460,802
Available-for-sale Securities, at Fair Value	425,416	556,538	472,340
Gross Unrealized Gains	12,226	11,529	11,841
Gross Unrealized Losses	406	256	303
Available-For-Sale Securities, Pledged as Collateral	276,357	291,147	344,341
Maturities of Debt Securities, at Amortized Cost
Within One Year	68,625
From 1 - 5 Years	322,666
From 5 - 10 Years	18,568
Over 10 Years	2,617
Maturities of Debt Securities at Fair Value
Within One Year	69,324
From 1 - 5 Years	332,636
From 5 - 10 Years	19,864
Over 10 Years	2,417
Securities in a Continuous Loss Position, at Fair Value
Less than 12 Months	42,056	40,318	18,042
12 Months or Longer	0	5,793	4,707
Total	42,056	46,111	22,749
Number of Securities in a Continuous Loss Position, in number of securities	82	26	16
Unrealized Losses on Securities in a Continuous Loss Position
Less than 12 Months	406	226	276
12 Months or Longer	0	30	27
Total	406	256	303
U.S. Agency Obligations [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-For-Sale Securities, at Amortized Cost	56,054	116,055	43,058
Available-for-sale Securities, at Fair Value	56,391	116,393	43,416
Gross Unrealized Gains	337	342	358
Gross Unrealized Losses	0	4	0
Maturities of Debt Securities, at Amortized Cost
Within One Year	31,007
From 1 - 5 Years	25,047
From 5 - 10 Years	0
Over 10 Years	0
Maturities of Debt Securities at Fair Value
Within One Year	31,012
From 1 - 5 Years	25,379
From 5 - 10 Years	0
Over 10 Years	0
Securities in a Continuous Loss Position, at Fair Value
Less than 12 Months	4,999	25,956	0
12 Months or Longer	0	0	0
Total	4,999	25,956	0
Number of Securities in a Continuous Loss Position, in number of securities	1	7	0
Unrealized Losses on Securities in a Continuous Loss Position
Less than 12 Months	0	4	0
12 Months or Longer	0	0	0
Total	0	4	0
State and Municipal Obligations [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-For-Sale Securities, at Amortized Cost	62,706	44,712	48,564
Available-for-sale Securities, at Fair Value	62,965	44,999	48,850
Gross Unrealized Gains	285	305	286
Gross Unrealized Losses	26	18	0
Maturities of Debt Securities, at Amortized Cost
Within One Year	15,777
From 1 - 5 Years	43,969
From 5 - 10 Years	1,343
Over 10 Years	1,617
Maturities of Debt Securities at Fair Value
Within One Year	15,818
From 1 - 5 Years	44,131
From 5 - 10 Years	1,399
Over 10 Years	1,617
Securities in a Continuous Loss Position, at Fair Value
Less than 12 Months	17,432	4,505	257
12 Months or Longer	0	0	0
Total	17,432	4,505	257
Number of Securities in a Continuous Loss Position, in number of securities	73	12	1
Unrealized Losses on Securities in a Continuous Loss Position
Less than 12 Months	26	18	0
12 Months or Longer	0	0	0
Total	26	18	0
Mortgage-Backed Securities - Residential [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-For-Sale Securities, at Amortized Cost	292,716	382,118	366,485
Available-for-sale Securities, at Fair Value	304,085	392,712	377,375
Gross Unrealized Gains	11,549	10,813	11,156
Gross Unrealized Losses	180	219	266
Maturities of Debt Securities, at Amortized Cost
Within One Year	21,841
From 1 - 5 Years	253,650
From 5 - 10 Years	17,225
Over 10 Years	0
Maturities of Debt Securities at Fair Value
Within One Year	22,494
From 1 - 5 Years	263,126
From 5 - 10 Years	18,465
Over 10 Years	0
Securities in a Continuous Loss Position, at Fair Value
Less than 12 Months	18,825	9,857	17,637
12 Months or Longer	0	5,715	4,390
Total	18,825	15,572	22,027
Number of Securities in a Continuous Loss Position, in number of securities	7	5	10
Unrealized Losses on Securities in a Continuous Loss Position
Less than 12 Months	180	204	251
12 Months or Longer	0	15	15
Total	180	219	266
Corporate and Other Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-For-Sale Securities, at Amortized Cost	1,000	1,015	1,330
Available-for-sale Securities, at Fair Value	800	1,015	1,318
Gross Unrealized Gains	0	0	0
Gross Unrealized Losses	200	0	12
Maturities of Debt Securities, at Amortized Cost
Within One Year	0
From 1 - 5 Years	0
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	0
From 5 - 10 Years	0
Over 10 Years	800
Securities in a Continuous Loss Position, at Fair Value
Less than 12 Months	800	0	0
12 Months or Longer	0	0	317
Total	800	0	317
Number of Securities in a Continuous Loss Position, in number of securities	1	0	1
Unrealized Losses on Securities in a Continuous Loss Position
Less than 12 Months	200	0	0
12 Months or Longer	0	0	12
Total	200	0	12
Mutual Funds and Equity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-For-Sale Securities, at Amortized Cost	1,120	1,365	1,365
Available-for-sale Securities, at Fair Value	1,175	1,419	1,381
Gross Unrealized Gains	55	69	41
Gross Unrealized Losses	0	15	25
Securities in a Continuous Loss Position, at Fair Value
Less than 12 Months	0	0	148
12 Months or Longer	0	78	0
Total	0	78	148
Number of Securities in a Continuous Loss Position, in number of securities		2	4
Unrealized Losses on Securities in a Continuous Loss Position
Less than 12 Months	0	0	25
12 Months or Longer	0	15	0
Total	$ 0	$ 15	$ 25